add FITPACK Fortran library
start developing of FITPACK C++ bindings mount_server.cpp: fix compilation error with GCC15
This commit is contained in:
parent
e1421a1c2e
commit
5279d1c41a
@ -105,6 +105,9 @@ include_directories(${ERFA_INCLUDE_DIR})
|
||||
|
||||
option(WITH_TESTS "Build tests" ON)
|
||||
|
||||
|
||||
add_subdirectory(fitpack)
|
||||
|
||||
# Mount client-to-server communication protocol
|
||||
# (extended LX200 protocol)
|
||||
#
|
||||
|
||||
29
cxx/fitpack/CMakeLists.txt
Normal file
29
cxx/fitpack/CMakeLists.txt
Normal file
@ -0,0 +1,29 @@
|
||||
cmake_minimum_required(VERSION 3.20)
|
||||
|
||||
set(func_name "")
|
||||
|
||||
file(GLOB src_files "*.f")
|
||||
|
||||
foreach(ff IN LISTS src_files)
|
||||
get_filename_component(sn ${ff} NAME_WE)
|
||||
list(APPEND func_name ${sn})
|
||||
endforeach()
|
||||
|
||||
# message(STATUS "${func_name}")
|
||||
|
||||
string(REPLACE ";" " " func_str "${func_name}")
|
||||
|
||||
# message(STATUS ${func_str})
|
||||
|
||||
enable_language(Fortran CXX)
|
||||
|
||||
include(FortranCInterface)
|
||||
FortranCInterface_HEADER(FortranCInterface.h
|
||||
MACRO_NAMESPACE "FC_"
|
||||
SYMBOL_NAMESPACE "fp_"
|
||||
SYMBOLS ${func_str}
|
||||
)
|
||||
|
||||
add_library(fitpack STATIC ${src_files} fitpack.h)
|
||||
|
||||
|
||||
19
cxx/fitpack/Makefile
Normal file
19
cxx/fitpack/Makefile
Normal file
@ -0,0 +1,19 @@
|
||||
# Makefile that builts a library lib$(LIB).a from all
|
||||
# of the Fortran files found in the current directory.
|
||||
# Usage: make LIB=<libname>
|
||||
# Pearu
|
||||
|
||||
OBJ=$(patsubst %.f,%.o,$(shell ls *.f))
|
||||
all: lib$(LIB).a
|
||||
$(OBJ):
|
||||
$(FC) -c $(FFLAGS) $(FSHARED) $(patsubst %.o,%.f,$(@F)) -o $@
|
||||
lib$(LIB).a: $(OBJ)
|
||||
$(AR) rus lib$(LIB).a $?
|
||||
clean:
|
||||
rm *.o
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
3
cxx/fitpack/README
Normal file
3
cxx/fitpack/README
Normal file
@ -0,0 +1,3 @@
|
||||
- ddierckx is a 'real*8' version of dierckx
|
||||
generated by Pearu Peterson <pearu@ioc.ee>.
|
||||
- dierckx (in netlib) is fitpack by P. Dierckx
|
||||
66
cxx/fitpack/bispeu.f
Normal file
66
cxx/fitpack/bispeu.f
Normal file
@ -0,0 +1,66 @@
|
||||
recursive subroutine bispeu(tx,nx,ty,ny,c,kx,ky,x,y,z,m,wrk,
|
||||
* lwrk, ier)
|
||||
implicit none
|
||||
c subroutine bispeu evaluates on a set of points (x(i),y(i)),i=1,...,m
|
||||
c a bivariate spline s(x,y) of degrees kx and ky, given in the
|
||||
c b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c call bispeu(tx,nx,ty,ny,c,kx,ky,x,y,z,m,wrk,lwrk,
|
||||
c * iwrk,kwrk,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c tx : real array, length nx, which contains the position of the
|
||||
c knots in the x-direction.
|
||||
c nx : integer, giving the total number of knots in the x-direction
|
||||
c ty : real array, length ny, which contains the position of the
|
||||
c knots in the y-direction.
|
||||
c ny : integer, giving the total number of knots in the y-direction
|
||||
c c : real array, length (nx-kx-1)*(ny-ky-1), which contains the
|
||||
c b-spline coefficients.
|
||||
c kx,ky : integer values, giving the degrees of the spline.
|
||||
c x : real array of dimension (mx).
|
||||
c y : real array of dimension (my).
|
||||
c m : on entry m must specify the number points. m >= 1.
|
||||
c wrk : real array of dimension lwrk. used as workspace.
|
||||
c lwrk : integer, specifying the dimension of wrk.
|
||||
c lwrk >= kx+ky+2
|
||||
c
|
||||
c output parameters:
|
||||
c z : real array of dimension m.
|
||||
c on successful exit z(i) contains the value of s(x,y)
|
||||
c at the point (x(i),y(i)), i=1,...,m.
|
||||
c ier : integer error flag
|
||||
c ier=0 : normal return
|
||||
c ier=10: invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c m >=1, lwrk>=mx*(kx+1)+my*(ky+1), kwrk>=mx+my
|
||||
c tx(kx+1) <= x(i-1) <= x(i) <= tx(nx-kx), i=2,...,mx
|
||||
c ty(ky+1) <= y(j-1) <= y(j) <= ty(ny-ky), j=2,...,my
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpbisp,fpbspl
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer nx,ny,kx,ky,m,lwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 tx(nx),ty(ny),c((nx-kx-1)*(ny-ky-1)),x(m),y(m),z(m),
|
||||
* wrk(lwrk)
|
||||
c ..local scalars..
|
||||
integer iwrk(2)
|
||||
integer i, lwest
|
||||
c ..
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
lwest = kx+ky+2
|
||||
if (lwrk.lt.lwest) go to 100
|
||||
if (m.lt.1) go to 100
|
||||
ier = 0
|
||||
do 10 i=1,m
|
||||
call fpbisp(tx,nx,ty,ny,c,kx,ky,x(i),1,y(i),1,z(i),wrk(1),
|
||||
* wrk(kx+2),iwrk(1),iwrk(2))
|
||||
10 continue
|
||||
100 return
|
||||
end
|
||||
104
cxx/fitpack/bispev.f
Normal file
104
cxx/fitpack/bispev.f
Normal file
@ -0,0 +1,104 @@
|
||||
recursive subroutine bispev(tx,nx,ty,ny,c,kx,ky,x,mx,y,my,z,
|
||||
* wrk,lwrk,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c subroutine bispev evaluates on a grid (x(i),y(j)),i=1,...,mx; j=1,...
|
||||
c ,my a bivariate spline s(x,y) of degrees kx and ky, given in the
|
||||
c b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c call bispev(tx,nx,ty,ny,c,kx,ky,x,mx,y,my,z,wrk,lwrk,
|
||||
c * iwrk,kwrk,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c tx : real array, length nx, which contains the position of the
|
||||
c knots in the x-direction.
|
||||
c nx : integer, giving the total number of knots in the x-direction
|
||||
c ty : real array, length ny, which contains the position of the
|
||||
c knots in the y-direction.
|
||||
c ny : integer, giving the total number of knots in the y-direction
|
||||
c c : real array, length (nx-kx-1)*(ny-ky-1), which contains the
|
||||
c b-spline coefficients.
|
||||
c kx,ky : integer values, giving the degrees of the spline.
|
||||
c x : real array of dimension (mx).
|
||||
c before entry x(i) must be set to the x co-ordinate of the
|
||||
c i-th grid point along the x-axis.
|
||||
c tx(kx+1)<=x(i-1)<=x(i)<=tx(nx-kx), i=2,...,mx.
|
||||
c mx : on entry mx must specify the number of grid points along
|
||||
c the x-axis. mx >=1.
|
||||
c y : real array of dimension (my).
|
||||
c before entry y(j) must be set to the y co-ordinate of the
|
||||
c j-th grid point along the y-axis.
|
||||
c ty(ky+1)<=y(j-1)<=y(j)<=ty(ny-ky), j=2,...,my.
|
||||
c my : on entry my must specify the number of grid points along
|
||||
c the y-axis. my >=1.
|
||||
c wrk : real array of dimension lwrk. used as workspace.
|
||||
c lwrk : integer, specifying the dimension of wrk.
|
||||
c lwrk >= mx*(kx+1)+my*(ky+1)
|
||||
c iwrk : integer array of dimension kwrk. used as workspace.
|
||||
c kwrk : integer, specifying the dimension of iwrk. kwrk >= mx+my.
|
||||
c
|
||||
c output parameters:
|
||||
c z : real array of dimension (mx*my).
|
||||
c on successful exit z(my*(i-1)+j) contains the value of s(x,y)
|
||||
c at the point (x(i),y(j)),i=1,...,mx;j=1,...,my.
|
||||
c ier : integer error flag
|
||||
c ier=0 : normal return
|
||||
c ier=10: invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c mx >=1, my >=1, lwrk>=mx*(kx+1)+my*(ky+1), kwrk>=mx+my
|
||||
c tx(kx+1) <= x(i-1) <= x(i) <= tx(nx-kx), i=2,...,mx
|
||||
c ty(ky+1) <= y(j-1) <= y(j) <= ty(ny-ky), j=2,...,my
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpbisp,fpbspl
|
||||
c
|
||||
c references :
|
||||
c de boor c : on calculating with b-splines, j. approximation theory
|
||||
c 6 (1972) 50-62.
|
||||
c cox m.g. : the numerical evaluation of b-splines, j. inst. maths
|
||||
c applics 10 (1972) 134-149.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer nx,ny,kx,ky,mx,my,lwrk,kwrk,ier
|
||||
c ..array arguments..
|
||||
integer iwrk(kwrk)
|
||||
real*8 tx(nx),ty(ny),c((nx-kx-1)*(ny-ky-1)),x(mx),y(my),z(mx*my),
|
||||
* wrk(lwrk)
|
||||
c ..local scalars..
|
||||
integer i,iw,lwest
|
||||
c ..
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
lwest = (kx+1)*mx+(ky+1)*my
|
||||
if(lwrk.lt.lwest) go to 100
|
||||
if(kwrk.lt.(mx+my)) go to 100
|
||||
if (mx.lt.1) go to 100
|
||||
if (mx.eq.1) go to 30
|
||||
go to 10
|
||||
10 do 20 i=2,mx
|
||||
if(x(i).lt.x(i-1)) go to 100
|
||||
20 continue
|
||||
30 if (my.lt.1) go to 100
|
||||
if (my.eq.1) go to 60
|
||||
go to 40
|
||||
40 do 50 i=2,my
|
||||
if(y(i).lt.y(i-1)) go to 100
|
||||
50 continue
|
||||
60 ier = 0
|
||||
iw = mx*(kx+1)+1
|
||||
call fpbisp(tx,nx,ty,ny,c,kx,ky,x,mx,y,my,z,wrk(1),wrk(iw),
|
||||
* iwrk(1),iwrk(mx+1))
|
||||
100 return
|
||||
end
|
||||
353
cxx/fitpack/clocur.f
Normal file
353
cxx/fitpack/clocur.f
Normal file
@ -0,0 +1,353 @@
|
||||
recursive subroutine clocur(iopt,ipar,idim,m,u,mx,x,w,k,s,nest,
|
||||
* n,t,nc,c,fp,wrk,lwrk,iwrk,ier)
|
||||
implicit none
|
||||
c given the ordered set of m points x(i) in the idim-dimensional space
|
||||
c with x(1)=x(m), and given also a corresponding set of strictly in-
|
||||
c creasing values u(i) and the set of positive numbers w(i),i=1,2,...,m
|
||||
c subroutine clocur determines a smooth approximating closed spline
|
||||
c curve s(u), i.e.
|
||||
c x1 = s1(u)
|
||||
c x2 = s2(u) u(1) <= u <= u(m)
|
||||
c .........
|
||||
c xidim = sidim(u)
|
||||
c with sj(u),j=1,2,...,idim periodic spline functions of degree k with
|
||||
c common knots t(j),j=1,2,...,n.
|
||||
c if ipar=1 the values u(i),i=1,2,...,m must be supplied by the user.
|
||||
c if ipar=0 these values are chosen automatically by clocur as
|
||||
c v(1) = 0
|
||||
c v(i) = v(i-1) + dist(x(i),x(i-1)) ,i=2,3,...,m
|
||||
c u(i) = v(i)/v(m) ,i=1,2,...,m
|
||||
c if iopt=-1 clocur calculates the weighted least-squares closed spline
|
||||
c curve according to a given set of knots.
|
||||
c if iopt>=0 the number of knots of the splines sj(u) and the position
|
||||
c t(j),j=1,2,...,n is chosen automatically by the routine. the smooth-
|
||||
c ness of s(u) is then achieved by minimalizing the discontinuity
|
||||
c jumps of the k-th derivative of s(u) at the knots t(j),j=k+2,k+3,...,
|
||||
c n-k-1. the amount of smoothness is determined by the condition that
|
||||
c f(p)=sum((w(i)*dist(x(i),s(u(i))))**2) be <= s, with s a given non-
|
||||
c negative constant, called the smoothing factor.
|
||||
c the fit s(u) is given in the b-spline representation and can be
|
||||
c evaluated by means of subroutine curev.
|
||||
c
|
||||
c calling sequence:
|
||||
c call clocur(iopt,ipar,idim,m,u,mx,x,w,k,s,nest,n,t,nc,c,
|
||||
c * fp,wrk,lwrk,iwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt : integer flag. on entry iopt must specify whether a weighted
|
||||
c least-squares closed spline curve (iopt=-1) or a smoothing
|
||||
c closed spline curve (iopt=0 or 1) must be determined. if
|
||||
c iopt=0 the routine will start with an initial set of knots
|
||||
c t(i)=u(1)+(u(m)-u(1))*(i-k-1),i=1,2,...,2*k+2. if iopt=1 the
|
||||
c routine will continue with the knots found at the last call.
|
||||
c attention: a call with iopt=1 must always be immediately
|
||||
c preceded by another call with iopt=1 or iopt=0.
|
||||
c unchanged on exit.
|
||||
c ipar : integer flag. on entry ipar must specify whether (ipar=1)
|
||||
c the user will supply the parameter values u(i),or whether
|
||||
c (ipar=0) these values are to be calculated by clocur.
|
||||
c unchanged on exit.
|
||||
c idim : integer. on entry idim must specify the dimension of the
|
||||
c curve. 0 < idim < 11.
|
||||
c unchanged on exit.
|
||||
c m : integer. on entry m must specify the number of data points.
|
||||
c m > 1. unchanged on exit.
|
||||
c u : real array of dimension at least (m). in case ipar=1,before
|
||||
c entry, u(i) must be set to the i-th value of the parameter
|
||||
c variable u for i=1,2,...,m. these values must then be
|
||||
c supplied in strictly ascending order and will be unchanged
|
||||
c on exit. in case ipar=0, on exit,the array will contain the
|
||||
c values u(i) as determined by clocur.
|
||||
c mx : integer. on entry mx must specify the actual dimension of
|
||||
c the array x as declared in the calling (sub)program. mx must
|
||||
c not be too small (see x). unchanged on exit.
|
||||
c x : real array of dimension at least idim*m.
|
||||
c before entry, x(idim*(i-1)+j) must contain the j-th coord-
|
||||
c inate of the i-th data point for i=1,2,...,m and j=1,2,...,
|
||||
c idim. since first and last data point must coincide it
|
||||
c means that x(j)=x(idim*(m-1)+j),j=1,2,...,idim.
|
||||
c unchanged on exit.
|
||||
c w : real array of dimension at least (m). before entry, w(i)
|
||||
c must be set to the i-th value in the set of weights. the
|
||||
c w(i) must be strictly positive. w(m) is not used.
|
||||
c unchanged on exit. see also further comments.
|
||||
c k : integer. on entry k must specify the degree of the splines.
|
||||
c 1<=k<=5. it is recommended to use cubic splines (k=3).
|
||||
c the user is strongly dissuaded from choosing k even,together
|
||||
c with a small s-value. unchanged on exit.
|
||||
c s : real.on entry (in case iopt>=0) s must specify the smoothing
|
||||
c factor. s >=0. unchanged on exit.
|
||||
c for advice on the choice of s see further comments.
|
||||
c nest : integer. on entry nest must contain an over-estimate of the
|
||||
c total number of knots of the splines returned, to indicate
|
||||
c the storage space available to the routine. nest >=2*k+2.
|
||||
c in most practical situation nest=m/2 will be sufficient.
|
||||
c always large enough is nest=m+2*k, the number of knots
|
||||
c needed for interpolation (s=0). unchanged on exit.
|
||||
c n : integer.
|
||||
c unless ier = 10 (in case iopt >=0), n will contain the
|
||||
c total number of knots of the smoothing spline curve returned
|
||||
c if the computation mode iopt=1 is used this value of n
|
||||
c should be left unchanged between subsequent calls.
|
||||
c in case iopt=-1, the value of n must be specified on entry.
|
||||
c t : real array of dimension at least (nest).
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline curve,i.e. the position of the interior knots t(k+2),
|
||||
c t(k+3),..,t(n-k-1) as well as the position of the additional
|
||||
c t(1),t(2),..,t(k+1)=u(1) and u(m)=t(n-k),...,t(n) needed for
|
||||
c the b-spline representation.
|
||||
c if the computation mode iopt=1 is used, the values of t(1),
|
||||
c t(2),...,t(n) should be left unchanged between subsequent
|
||||
c calls. if the computation mode iopt=-1 is used, the values
|
||||
c t(k+2),...,t(n-k-1) must be supplied by the user, before
|
||||
c entry. see also the restrictions (ier=10).
|
||||
c nc : integer. on entry nc must specify the actual dimension of
|
||||
c the array c as declared in the calling (sub)program. nc
|
||||
c must not be too small (see c). unchanged on exit.
|
||||
c c : real array of dimension at least (nest*idim).
|
||||
c on successful exit, this array will contain the coefficients
|
||||
c in the b-spline representation of the spline curve s(u),i.e.
|
||||
c the b-spline coefficients of the spline sj(u) will be given
|
||||
c in c(n*(j-1)+i),i=1,2,...,n-k-1 for j=1,2,...,idim.
|
||||
c fp : real. unless ier = 10, fp contains the weighted sum of
|
||||
c squared residuals of the spline curve returned.
|
||||
c wrk : real array of dimension at least m*(k+1)+nest*(7+idim+5*k).
|
||||
c used as working space. if the computation mode iopt=1 is
|
||||
c used, the values wrk(1),...,wrk(n) should be left unchanged
|
||||
c between subsequent calls.
|
||||
c lwrk : integer. on entry,lwrk must specify the actual dimension of
|
||||
c the array wrk as declared in the calling (sub)program. lwrk
|
||||
c must not be too small (see wrk). unchanged on exit.
|
||||
c iwrk : integer array of dimension at least (nest).
|
||||
c used as working space. if the computation mode iopt=1 is
|
||||
c used,the values iwrk(1),...,iwrk(n) should be left unchanged
|
||||
c between subsequent calls.
|
||||
c ier : integer. unless the routine detects an error, ier contains a
|
||||
c non-positive value on exit, i.e.
|
||||
c ier=0 : normal return. the close curve returned has a residual
|
||||
c sum of squares fp such that abs(fp-s)/s <= tol with tol a
|
||||
c relative tolerance set to 0.001 by the program.
|
||||
c ier=-1 : normal return. the curve returned is an interpolating
|
||||
c spline curve (fp=0).
|
||||
c ier=-2 : normal return. the curve returned is the weighted least-
|
||||
c squares point,i.e. each spline sj(u) is a constant. in
|
||||
c this extreme case fp gives the upper bound fp0 for the
|
||||
c smoothing factor s.
|
||||
c ier=1 : error. the required storage space exceeds the available
|
||||
c storage space, as specified by the parameter nest.
|
||||
c probably causes : nest too small. if nest is already
|
||||
c large (say nest > m/2), it may also indicate that s is
|
||||
c too small
|
||||
c the approximation returned is the least-squares closed
|
||||
c curve according to the knots t(1),t(2),...,t(n). (n=nest)
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=2 : error. a theoretically impossible result was found during
|
||||
c the iteration process for finding a smoothing curve with
|
||||
c fp = s. probably causes : s too small.
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=3 : error. the maximal number of iterations maxit (set to 20
|
||||
c by the program) allowed for finding a smoothing curve
|
||||
c with fp=s has been reached. probably causes : s too small
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=10 : error. on entry, the input data are controlled on validity
|
||||
c the following restrictions must be satisfied.
|
||||
c -1<=iopt<=1, 1<=k<=5, m>1, nest>2*k+2, w(i)>0,i=1,2,...,m
|
||||
c 0<=ipar<=1, 0<idim<=10, lwrk>=(k+1)*m+nest*(7+idim+5*k),
|
||||
c nc>=nest*idim, x(j)=x(idim*(m-1)+j), j=1,2,...,idim
|
||||
c if ipar=0: sum j=1,idim (x(i*idim+j)-x((i-1)*idim+j))**2>0
|
||||
c i=1,2,...,m-1.
|
||||
c if ipar=1: u(1)<u(2)<...<u(m)
|
||||
c if iopt=-1: 2*k+2<=n<=min(nest,m+2*k)
|
||||
c u(1)<t(k+2)<t(k+3)<...<t(n-k-1)<u(m)
|
||||
c (u(1)=0 and u(m)=1 in case ipar=0)
|
||||
c the schoenberg-whitney conditions, i.e. there
|
||||
c must be a subset of data points uu(j) with
|
||||
c uu(j) = u(i) or u(i)+(u(m)-u(1)) such that
|
||||
c t(j) < uu(j) < t(j+k+1), j=k+1,...,n-k-1
|
||||
c if iopt>=0: s>=0
|
||||
c if s=0 : nest >= m+2*k
|
||||
c if one of these conditions is found to be violated,control
|
||||
c is immediately repassed to the calling program. in that
|
||||
c case there is no approximation returned.
|
||||
c
|
||||
c further comments:
|
||||
c by means of the parameter s, the user can control the tradeoff
|
||||
c between closeness of fit and smoothness of fit of the approximation.
|
||||
c if s is too large, the curve will be too smooth and signal will be
|
||||
c lost ; if s is too small the curve will pick up too much noise. in
|
||||
c the extreme cases the program will return an interpolating curve if
|
||||
c s=0 and the weighted least-squares point if s is very large.
|
||||
c between these extremes, a properly chosen s will result in a good
|
||||
c compromise between closeness of fit and smoothness of fit.
|
||||
c to decide whether an approximation, corresponding to a certain s is
|
||||
c satisfactory the user is highly recommended to inspect the fits
|
||||
c graphically.
|
||||
c recommended values for s depend on the weights w(i). if these are
|
||||
c taken as 1/d(i) with d(i) an estimate of the standard deviation of
|
||||
c x(i), a good s-value should be found in the range (m-sqrt(2*m),m+
|
||||
c sqrt(2*m)). if nothing is known about the statistical error in x(i)
|
||||
c each w(i) can be set equal to one and s determined by trial and
|
||||
c error, taking account of the comments above. the best is then to
|
||||
c start with a very large value of s ( to determine the weighted
|
||||
c least-squares point and the upper bound fp0 for s) and then to
|
||||
c progressively decrease the value of s ( say by a factor 10 in the
|
||||
c beginning, i.e. s=fp0/10, fp0/100,...and more carefully as the
|
||||
c approximating curve shows more detail) to obtain closer fits.
|
||||
c to economize the search for a good s-value the program provides with
|
||||
c different modes of computation. at the first call of the routine, or
|
||||
c whenever he wants to restart with the initial set of knots the user
|
||||
c must set iopt=0.
|
||||
c if iopt=1 the program will continue with the set of knots found at
|
||||
c the last call of the routine. this will save a lot of computation
|
||||
c time if clocur is called repeatedly for different values of s.
|
||||
c the number of knots of the spline returned and their location will
|
||||
c depend on the value of s and on the complexity of the shape of the
|
||||
c curve underlying the data. but, if the computation mode iopt=1 is
|
||||
c used, the knots returned may also depend on the s-values at previous
|
||||
c calls (if these were smaller). therefore, if after a number of
|
||||
c trials with different s-values and iopt=1, the user can finally
|
||||
c accept a fit as satisfactory, it may be worthwhile for him to call
|
||||
c clocur once more with the selected value for s but now with iopt=0.
|
||||
c indeed, clocur may then return an approximation of the same quality
|
||||
c of fit but with fewer knots and therefore better if data reduction
|
||||
c is also an important objective for the user.
|
||||
c
|
||||
c the form of the approximating curve can strongly be affected by
|
||||
c the choice of the parameter values u(i). if there is no physical
|
||||
c reason for choosing a particular parameter u, often good results
|
||||
c will be obtained with the choice of clocur(in case ipar=0), i.e.
|
||||
c v(1)=0, v(i)=v(i-1)+q(i), i=2,...,m, u(i)=v(i)/v(m), i=1,..,m
|
||||
c where
|
||||
c q(i)= sqrt(sum j=1,idim (xj(i)-xj(i-1))**2 )
|
||||
c other possibilities for q(i) are
|
||||
c q(i)= sum j=1,idim (xj(i)-xj(i-1))**2
|
||||
c q(i)= sum j=1,idim abs(xj(i)-xj(i-1))
|
||||
c q(i)= max j=1,idim abs(xj(i)-xj(i-1))
|
||||
c q(i)= 1
|
||||
c
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpbacp,fpbspl,fpchep,fpclos,fpdisc,fpgivs,fpknot,fprati,fprota
|
||||
c
|
||||
c references:
|
||||
c dierckx p. : algorithms for smoothing data with periodic and
|
||||
c parametric splines, computer graphics and image
|
||||
c processing 20 (1982) 171-184.
|
||||
c dierckx p. : algorithms for smoothing data with periodic and param-
|
||||
c etric splines, report tw55, dept. computer science,
|
||||
c k.u.leuven, 1981.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u. leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : may 1979
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 s,fp
|
||||
integer iopt,ipar,idim,m,mx,k,nest,n,nc,lwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 u(m),x(mx),w(m),t(nest),c(nc),wrk(lwrk)
|
||||
integer iwrk(nest)
|
||||
c ..local scalars..
|
||||
real*8 per,tol,dist
|
||||
integer i,ia1,ia2,ib,ifp,ig1,ig2,iq,iz,i1,i2,j1,j2,k1,k2,lwest,
|
||||
* maxit,m1,nmin,ncc,j
|
||||
c ..function references..
|
||||
real*8 sqrt
|
||||
c we set up the parameters tol and maxit
|
||||
maxit = 20
|
||||
tol = 0.1e-02
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(iopt.lt.(-1) .or. iopt.gt.1) go to 90
|
||||
if(ipar.lt.0 .or. ipar.gt.1) go to 90
|
||||
if(idim.le.0 .or. idim.gt.10) go to 90
|
||||
if(k.le.0 .or. k.gt.5) go to 90
|
||||
k1 = k+1
|
||||
k2 = k1+1
|
||||
nmin = 2*k1
|
||||
if(m.lt.2 .or. nest.lt.nmin) go to 90
|
||||
ncc = nest*idim
|
||||
if(mx.lt.m*idim .or. nc.lt.ncc) go to 90
|
||||
lwest = m*k1+nest*(7+idim+5*k)
|
||||
if(lwrk.lt.lwest) go to 90
|
||||
i1 = idim
|
||||
i2 = m*idim
|
||||
do 5 j=1,idim
|
||||
if(x(i1).ne.x(i2)) go to 90
|
||||
i1 = i1-1
|
||||
i2 = i2-1
|
||||
5 continue
|
||||
if(ipar.ne.0 .or. iopt.gt.0) go to 40
|
||||
i1 = 0
|
||||
i2 = idim
|
||||
u(1) = 0.
|
||||
do 20 i=2,m
|
||||
dist = 0.
|
||||
do 10 j1=1,idim
|
||||
i1 = i1+1
|
||||
i2 = i2+1
|
||||
dist = dist+(x(i2)-x(i1))**2
|
||||
10 continue
|
||||
u(i) = u(i-1)+sqrt(dist)
|
||||
20 continue
|
||||
if(u(m).le.0.) go to 90
|
||||
do 30 i=2,m
|
||||
u(i) = u(i)/u(m)
|
||||
30 continue
|
||||
u(m) = 0.1e+01
|
||||
40 if(w(1).le.0.) go to 90
|
||||
m1 = m-1
|
||||
do 50 i=1,m1
|
||||
if(u(i).ge.u(i+1) .or. w(i).le.0.) go to 90
|
||||
50 continue
|
||||
if(iopt.ge.0) go to 70
|
||||
if(n.le.nmin .or. n.gt.nest) go to 90
|
||||
per = u(m)-u(1)
|
||||
j1 = k1
|
||||
t(j1) = u(1)
|
||||
i1 = n-k
|
||||
t(i1) = u(m)
|
||||
j2 = j1
|
||||
i2 = i1
|
||||
do 60 i=1,k
|
||||
i1 = i1+1
|
||||
i2 = i2-1
|
||||
j1 = j1+1
|
||||
j2 = j2-1
|
||||
t(j2) = t(i2)-per
|
||||
t(i1) = t(j1)+per
|
||||
60 continue
|
||||
call fpchep(u,m,t,n,k,ier)
|
||||
if (ier.eq.0) go to 80
|
||||
go to 90
|
||||
70 if(s.lt.0.) go to 90
|
||||
if(s.eq.0. .and. nest.lt.(m+2*k)) go to 90
|
||||
ier = 0
|
||||
c we partition the working space and determine the spline approximation.
|
||||
80 ifp = 1
|
||||
iz = ifp+nest
|
||||
ia1 = iz+ncc
|
||||
ia2 = ia1+nest*k1
|
||||
ib = ia2+nest*k
|
||||
ig1 = ib+nest*k2
|
||||
ig2 = ig1+nest*k2
|
||||
iq = ig2+nest*k1
|
||||
call fpclos(iopt,idim,m,u,mx,x,w,k,s,nest,tol,maxit,k1,k2,n,t,
|
||||
* ncc,c,fp,wrk(ifp),wrk(iz),wrk(ia1),wrk(ia2),wrk(ib),wrk(ig1),
|
||||
* wrk(ig2),wrk(iq),iwrk,ier)
|
||||
90 return
|
||||
end
|
||||
181
cxx/fitpack/cocosp.f
Normal file
181
cxx/fitpack/cocosp.f
Normal file
@ -0,0 +1,181 @@
|
||||
recursive subroutine cocosp(m,x,y,w,n,t,e,maxtr,maxbin,c,sq,
|
||||
* sx,bind,wrk,lwrk,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c given the set of data points (x(i),y(i)) and the set of positive
|
||||
c numbers w(i),i=1,2,...,m, subroutine cocosp determines the weighted
|
||||
c least-squares cubic spline s(x) with given knots t(j),j=1,2,...,n
|
||||
c which satisfies the following concavity/convexity conditions
|
||||
c s''(t(j+3))*e(j) <= 0, j=1,2,...n-6
|
||||
c the fit is given in the b-spline representation( b-spline coef-
|
||||
c ficients c(j),j=1,2,...n-4) and can be evaluated by means of
|
||||
c subroutine splev.
|
||||
c
|
||||
c calling sequence:
|
||||
c call cocosp(m,x,y,w,n,t,e,maxtr,maxbin,c,sq,sx,bind,wrk,
|
||||
c * lwrk,iwrk,kwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c m : integer. on entry m must specify the number of data points.
|
||||
c m > 3. unchanged on exit.
|
||||
c x : real array of dimension at least (m). before entry, x(i)
|
||||
c must be set to the i-th value of the independent variable x,
|
||||
c for i=1,2,...,m. these values must be supplied in strictly
|
||||
c ascending order. unchanged on exit.
|
||||
c y : real array of dimension at least (m). before entry, y(i)
|
||||
c must be set to the i-th value of the dependent variable y,
|
||||
c for i=1,2,...,m. unchanged on exit.
|
||||
c w : real array of dimension at least (m). before entry, w(i)
|
||||
c must be set to the i-th value in the set of weights. the
|
||||
c w(i) must be strictly positive. unchanged on exit.
|
||||
c n : integer. on entry n must contain the total number of knots
|
||||
c of the cubic spline. m+4>=n>=8. unchanged on exit.
|
||||
c t : real array of dimension at least (n). before entry, this
|
||||
c array must contain the knots of the spline, i.e. the position
|
||||
c of the interior knots t(5),t(6),...,t(n-4) as well as the
|
||||
c position of the boundary knots t(1),t(2),t(3),t(4) and t(n-3)
|
||||
c t(n-2),t(n-1),t(n) needed for the b-spline representation.
|
||||
c unchanged on exit. see also the restrictions (ier=10).
|
||||
c e : real array of dimension at least (n). before entry, e(j)
|
||||
c must be set to 1 if s(x) must be locally concave at t(j+3),
|
||||
c to (-1) if s(x) must be locally convex at t(j+3) and to 0
|
||||
c if no convexity constraint is imposed at t(j+3),j=1,2,..,n-6.
|
||||
c e(n-5),...,e(n) are not used. unchanged on exit.
|
||||
c maxtr : integer. on entry maxtr must contain an over-estimate of the
|
||||
c total number of records in the used tree structure, to indic-
|
||||
c ate the storage space available to the routine. maxtr >=1
|
||||
c in most practical situation maxtr=100 will be sufficient.
|
||||
c always large enough is
|
||||
c n-5 n-6
|
||||
c maxtr = ( ) + ( ) with l the greatest
|
||||
c l l+1
|
||||
c integer <= (n-6)/2 . unchanged on exit.
|
||||
c maxbin: integer. on entry maxbin must contain an over-estimate of the
|
||||
c number of knots where s(x) will have a zero second derivative
|
||||
c maxbin >=1. in most practical situation maxbin = 10 will be
|
||||
c sufficient. always large enough is maxbin=n-6.
|
||||
c unchanged on exit.
|
||||
c c : real array of dimension at least (n).
|
||||
c on successful exit, this array will contain the coefficients
|
||||
c c(1),c(2),..,c(n-4) in the b-spline representation of s(x)
|
||||
c sq : real. on successful exit, sq contains the weighted sum of
|
||||
c squared residuals of the spline approximation returned.
|
||||
c sx : real array of dimension at least m. on successful exit
|
||||
c this array will contain the spline values s(x(i)),i=1,...,m
|
||||
c bind : logical array of dimension at least (n). on successful exit
|
||||
c this array will indicate the knots where s''(x)=0, i.e.
|
||||
c s''(t(j+3)) .eq. 0 if bind(j) = .true.
|
||||
c s''(t(j+3)) .ne. 0 if bind(j) = .false., j=1,2,...,n-6
|
||||
c wrk : real array of dimension at least m*4+n*7+maxbin*(maxbin+n+1)
|
||||
c used as working space.
|
||||
c lwrk : integer. on entry,lwrk must specify the actual dimension of
|
||||
c the array wrk as declared in the calling (sub)program.lwrk
|
||||
c must not be too small (see wrk). unchanged on exit.
|
||||
c iwrk : integer array of dimension at least (maxtr*4+2*(maxbin+1))
|
||||
c used as working space.
|
||||
c kwrk : integer. on entry,kwrk must specify the actual dimension of
|
||||
c the array iwrk as declared in the calling (sub)program. kwrk
|
||||
c must not be too small (see iwrk). unchanged on exit.
|
||||
c ier : integer. error flag
|
||||
c ier=0 : successful exit.
|
||||
c ier>0 : abnormal termination: no approximation is returned
|
||||
c ier=1 : the number of knots where s''(x)=0 exceeds maxbin.
|
||||
c probably causes : maxbin too small.
|
||||
c ier=2 : the number of records in the tree structure exceeds
|
||||
c maxtr.
|
||||
c probably causes : maxtr too small.
|
||||
c ier=3 : the algorithm finds no solution to the posed quadratic
|
||||
c programming problem.
|
||||
c probably causes : rounding errors.
|
||||
c ier=10 : on entry, the input data are controlled on validity.
|
||||
c the following restrictions must be satisfied
|
||||
c m>3, maxtr>=1, maxbin>=1, 8<=n<=m+4,w(i) > 0,
|
||||
c x(1)<x(2)<...<x(m), t(1)<=t(2)<=t(3)<=t(4)<=x(1),
|
||||
c x(1)<t(5)<t(6)<...<t(n-4)<x(m)<=t(n-3)<=...<=t(n),
|
||||
c kwrk>=maxtr*4+2*(maxbin+1),
|
||||
c lwrk>=m*4+n*7+maxbin*(maxbin+n+1),
|
||||
c the schoenberg-whitney conditions, i.e. there must
|
||||
c be a subset of data points xx(j) such that
|
||||
c t(j) < xx(j) < t(j+4), j=1,2,...,n-4
|
||||
c if one of these restrictions is found to be violated
|
||||
c control is immediately repassed to the calling program
|
||||
c
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpcosp,fpbspl,fpadno,fpdeno,fpseno,fpfrno,fpchec
|
||||
c
|
||||
c references:
|
||||
c dierckx p. : an algorithm for cubic spline fitting with convexity
|
||||
c constraints, computing 24 (1980) 349-371.
|
||||
c dierckx p. : an algorithm for least-squares cubic spline fitting
|
||||
c with convexity and concavity constraints, report tw39,
|
||||
c dept. computer science, k.u.leuven, 1978.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p. dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : march 1978
|
||||
c latest update : march 1987.
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 sq
|
||||
integer m,n,maxtr,maxbin,lwrk,kwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),y(m),w(m),t(n),e(n),c(n),sx(m),wrk(lwrk)
|
||||
integer iwrk(kwrk)
|
||||
logical bind(n)
|
||||
c ..local scalars..
|
||||
integer i,ia,ib,ic,iq,iu,iz,izz,ji,jib,jjb,jl,jr,ju,kwest,
|
||||
* lwest,mb,nm,n6
|
||||
real*8 one
|
||||
c ..
|
||||
c set constant
|
||||
one = 0.1e+01
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(m.lt.4 .or. n.lt.8) go to 40
|
||||
if(maxtr.lt.1 .or. maxbin.lt.1) go to 40
|
||||
lwest = 7*n+m*4+maxbin*(1+n+maxbin)
|
||||
kwest = 4*maxtr+2*(maxbin+1)
|
||||
if(lwrk.lt.lwest .or. kwrk.lt.kwest) go to 40
|
||||
if(w(1).le.0.) go to 40
|
||||
do 10 i=2,m
|
||||
if(x(i-1).ge.x(i) .or. w(i).le.0.) go to 40
|
||||
10 continue
|
||||
call fpchec(x,m,t,n,3,ier)
|
||||
if (ier.eq.0) go to 20
|
||||
go to 40
|
||||
c set numbers e(i)
|
||||
20 n6 = n-6
|
||||
do 30 i=1,n6
|
||||
if(e(i).gt.0.) e(i) = one
|
||||
if(e(i).lt.0.) e(i) = -one
|
||||
30 continue
|
||||
c we partition the working space and determine the spline approximation
|
||||
nm = n+maxbin
|
||||
mb = maxbin+1
|
||||
ia = 1
|
||||
ib = ia+4*n
|
||||
ic = ib+nm*maxbin
|
||||
iz = ic+n
|
||||
izz = iz+n
|
||||
iu = izz+n
|
||||
iq = iu+maxbin
|
||||
ji = 1
|
||||
ju = ji+maxtr
|
||||
jl = ju+maxtr
|
||||
jr = jl+maxtr
|
||||
jjb = jr+maxtr
|
||||
jib = jjb+mb
|
||||
call fpcosp(m,x,y,w,n,t,e,maxtr,maxbin,c,sq,sx,bind,nm,mb,wrk(ia),
|
||||
*
|
||||
* wrk(ib),wrk(ic),wrk(iz),wrk(izz),wrk(iu),wrk(iq),iwrk(ji),
|
||||
* iwrk(ju),iwrk(jl),iwrk(jr),iwrk(jjb),iwrk(jib),ier)
|
||||
40 return
|
||||
end
|
||||
234
cxx/fitpack/concon.f
Normal file
234
cxx/fitpack/concon.f
Normal file
@ -0,0 +1,234 @@
|
||||
recursive subroutine concon(iopt,m,x,y,w,v,s,nest,maxtr,maxbin,
|
||||
* n,t,c,sq,sx,bind,wrk,lwrk,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c given the set of data points (x(i),y(i)) and the set of positive
|
||||
c numbers w(i), i=1,2,...,m,subroutine concon determines a cubic spline
|
||||
c approximation s(x) which satisfies the following local convexity
|
||||
c constraints s''(x(i))*v(i) <= 0, i=1,2,...,m.
|
||||
c the number of knots n and the position t(j),j=1,2,...n is chosen
|
||||
c automatically by the routine in a way that
|
||||
c sq = sum((w(i)*(y(i)-s(x(i))))**2) be <= s.
|
||||
c the fit is given in the b-spline representation (b-spline coef-
|
||||
c ficients c(j),j=1,2,...n-4) and can be evaluated by means of
|
||||
c subroutine splev.
|
||||
c
|
||||
c calling sequence:
|
||||
c
|
||||
c call concon(iopt,m,x,y,w,v,s,nest,maxtr,maxbin,n,t,c,sq,
|
||||
c * sx,bind,wrk,lwrk,iwrk,kwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt: integer flag.
|
||||
c if iopt=0, the routine will start with the minimal number of
|
||||
c knots to guarantee that the convexity conditions will be
|
||||
c satisfied. if iopt=1, the routine will continue with the set
|
||||
c of knots found at the last call of the routine.
|
||||
c attention: a call with iopt=1 must always be immediately
|
||||
c preceded by another call with iopt=1 or iopt=0.
|
||||
c unchanged on exit.
|
||||
c m : integer. on entry m must specify the number of data points.
|
||||
c m > 3. unchanged on exit.
|
||||
c x : real array of dimension at least (m). before entry, x(i)
|
||||
c must be set to the i-th value of the independent variable x,
|
||||
c for i=1,2,...,m. these values must be supplied in strictly
|
||||
c ascending order. unchanged on exit.
|
||||
c y : real array of dimension at least (m). before entry, y(i)
|
||||
c must be set to the i-th value of the dependent variable y,
|
||||
c for i=1,2,...,m. unchanged on exit.
|
||||
c w : real array of dimension at least (m). before entry, w(i)
|
||||
c must be set to the i-th value in the set of weights. the
|
||||
c w(i) must be strictly positive. unchanged on exit.
|
||||
c v : real array of dimension at least (m). before entry, v(i)
|
||||
c must be set to 1 if s(x) must be locally concave at x(i),
|
||||
c to (-1) if s(x) must be locally convex at x(i) and to 0
|
||||
c if no convexity constraint is imposed at x(i).
|
||||
c s : real. on entry s must specify an over-estimate for the
|
||||
c the weighted sum of squared residuals sq of the requested
|
||||
c spline. s >=0. unchanged on exit.
|
||||
c nest : integer. on entry nest must contain an over-estimate of the
|
||||
c total number of knots of the spline returned, to indicate
|
||||
c the storage space available to the routine. nest >=8.
|
||||
c in most practical situation nest=m/2 will be sufficient.
|
||||
c always large enough is nest=m+4. unchanged on exit.
|
||||
c maxtr : integer. on entry maxtr must contain an over-estimate of the
|
||||
c total number of records in the used tree structure, to indic-
|
||||
c ate the storage space available to the routine. maxtr >=1
|
||||
c in most practical situation maxtr=100 will be sufficient.
|
||||
c always large enough is
|
||||
c nest-5 nest-6
|
||||
c maxtr = ( ) + ( ) with l the greatest
|
||||
c l l+1
|
||||
c integer <= (nest-6)/2 . unchanged on exit.
|
||||
c maxbin: integer. on entry maxbin must contain an over-estimate of the
|
||||
c number of knots where s(x) will have a zero second derivative
|
||||
c maxbin >=1. in most practical situation maxbin = 10 will be
|
||||
c sufficient. always large enough is maxbin=nest-6.
|
||||
c unchanged on exit.
|
||||
c n : integer.
|
||||
c on exit with ier <=0, n will contain the total number of
|
||||
c knots of the spline approximation returned. if the comput-
|
||||
c ation mode iopt=1 is used this value of n should be left
|
||||
c unchanged between subsequent calls.
|
||||
c t : real array of dimension at least (nest).
|
||||
c on exit with ier<=0, this array will contain the knots of the
|
||||
c spline,i.e. the position of the interior knots t(5),t(6),...,
|
||||
c t(n-4) as well as the position of the additional knots
|
||||
c t(1)=t(2)=t(3)=t(4)=x(1) and t(n-3)=t(n-2)=t(n-1)=t(n)=x(m)
|
||||
c needed for the b-spline representation.
|
||||
c if the computation mode iopt=1 is used, the values of t(1),
|
||||
c t(2),...,t(n) should be left unchanged between subsequent
|
||||
c calls.
|
||||
c c : real array of dimension at least (nest).
|
||||
c on successful exit, this array will contain the coefficients
|
||||
c c(1),c(2),..,c(n-4) in the b-spline representation of s(x)
|
||||
c sq : real. unless ier>0 , sq contains the weighted sum of
|
||||
c squared residuals of the spline approximation returned.
|
||||
c sx : real array of dimension at least m. on exit with ier<=0
|
||||
c this array will contain the spline values s(x(i)),i=1,...,m
|
||||
c if the computation mode iopt=1 is used, the values of sx(1),
|
||||
c sx(2),...,sx(m) should be left unchanged between subsequent
|
||||
c calls.
|
||||
c bind: logical array of dimension at least nest. on exit with ier<=0
|
||||
c this array will indicate the knots where s''(x)=0, i.e.
|
||||
c s''(t(j+3)) .eq. 0 if bind(j) = .true.
|
||||
c s''(t(j+3)) .ne. 0 if bind(j) = .false., j=1,2,...,n-6
|
||||
c if the computation mode iopt=1 is used, the values of bind(1)
|
||||
c ,...,bind(n-6) should be left unchanged between subsequent
|
||||
c calls.
|
||||
c wrk : real array of dimension at least (m*4+nest*8+maxbin*(maxbin+
|
||||
c nest+1)). used as working space.
|
||||
c lwrk : integer. on entry,lwrk must specify the actual dimension of
|
||||
c the array wrk as declared in the calling (sub)program.lwrk
|
||||
c must not be too small (see wrk). unchanged on exit.
|
||||
c iwrk : integer array of dimension at least (maxtr*4+2*(maxbin+1))
|
||||
c used as working space.
|
||||
c kwrk : integer. on entry,kwrk must specify the actual dimension of
|
||||
c the array iwrk as declared in the calling (sub)program. kwrk
|
||||
c must not be too small (see iwrk). unchanged on exit.
|
||||
c ier : integer. error flag
|
||||
c ier=0 : normal return, s(x) satisfies the concavity/convexity
|
||||
c constraints and sq <= s.
|
||||
c ier<0 : abnormal termination: s(x) satisfies the concavity/
|
||||
c convexity constraints but sq > s.
|
||||
c ier=-3 : the requested storage space exceeds the available
|
||||
c storage space as specified by the parameter nest.
|
||||
c probably causes: nest too small. if nest is already
|
||||
c large (say nest > m/2), it may also indicate that s
|
||||
c is too small.
|
||||
c the approximation returned is the least-squares cubic
|
||||
c spline according to the knots t(1),...,t(n) (n=nest)
|
||||
c which satisfies the convexity constraints.
|
||||
c ier=-2 : the maximal number of knots n=m+4 has been reached.
|
||||
c probably causes: s too small.
|
||||
c ier=-1 : the number of knots n is less than the maximal number
|
||||
c m+4 but concon finds that adding one or more knots
|
||||
c will not further reduce the value of sq.
|
||||
c probably causes : s too small.
|
||||
c ier>0 : abnormal termination: no approximation is returned
|
||||
c ier=1 : the number of knots where s''(x)=0 exceeds maxbin.
|
||||
c probably causes : maxbin too small.
|
||||
c ier=2 : the number of records in the tree structure exceeds
|
||||
c maxtr.
|
||||
c probably causes : maxtr too small.
|
||||
c ier=3 : the algorithm finds no solution to the posed quadratic
|
||||
c programming problem.
|
||||
c probably causes : rounding errors.
|
||||
c ier=4 : the minimum number of knots (given by n) to guarantee
|
||||
c that the concavity/convexity conditions will be
|
||||
c satisfied is greater than nest.
|
||||
c probably causes: nest too small.
|
||||
c ier=5 : the minimum number of knots (given by n) to guarantee
|
||||
c that the concavity/convexity conditions will be
|
||||
c satisfied is greater than m+4.
|
||||
c probably causes: strongly alternating convexity and
|
||||
c concavity conditions. normally the situation can be
|
||||
c coped with by adding n-m-4 extra data points (found
|
||||
c by linear interpolation e.g.) with a small weight w(i)
|
||||
c and a v(i) number equal to zero.
|
||||
c ier=10 : on entry, the input data are controlled on validity.
|
||||
c the following restrictions must be satisfied
|
||||
c 0<=iopt<=1, m>3, nest>=8, s>=0, maxtr>=1, maxbin>=1,
|
||||
c kwrk>=maxtr*4+2*(maxbin+1), w(i)>0, x(i) < x(i+1),
|
||||
c lwrk>=m*4+nest*8+maxbin*(maxbin+nest+1)
|
||||
c if one of these restrictions is found to be violated
|
||||
c control is immediately repassed to the calling program
|
||||
c
|
||||
c further comments:
|
||||
c as an example of the use of the computation mode iopt=1, the
|
||||
c following program segment will cause concon to return control
|
||||
c each time a spline with a new set of knots has been computed.
|
||||
c .............
|
||||
c iopt = 0
|
||||
c s = 0.1e+60 (s very large)
|
||||
c do 10 i=1,m
|
||||
c call concon(iopt,m,x,y,w,v,s,nest,maxtr,maxbin,n,t,c,sq,sx,
|
||||
c * bind,wrk,lwrk,iwrk,kwrk,ier)
|
||||
c ......
|
||||
c s = sq
|
||||
c iopt=1
|
||||
c 10 continue
|
||||
c .............
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpcoco,fpcosp,fpbspl,fpadno,fpdeno,fpseno,fpfrno
|
||||
c
|
||||
c references:
|
||||
c dierckx p. : an algorithm for cubic spline fitting with convexity
|
||||
c constraints, computing 24 (1980) 349-371.
|
||||
c dierckx p. : an algorithm for least-squares cubic spline fitting
|
||||
c with convexity and concavity constraints, report tw39,
|
||||
c dept. computer science, k.u.leuven, 1978.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p. dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : march 1978
|
||||
c latest update : march 1987.
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 s,sq
|
||||
integer iopt,m,nest,maxtr,maxbin,n,lwrk,kwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),y(m),w(m),v(m),t(nest),c(nest),sx(m),wrk(lwrk)
|
||||
integer iwrk(kwrk)
|
||||
logical bind(nest)
|
||||
c ..local scalars..
|
||||
integer i,lwest,kwest,ie,iw,lww
|
||||
real*8 one
|
||||
c ..
|
||||
c set constant
|
||||
one = 0.1e+01
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(iopt.lt.0 .or. iopt.gt.1) go to 30
|
||||
if(m.lt.4 .or. nest.lt.8) go to 30
|
||||
if(s.lt.0.) go to 30
|
||||
if(maxtr.lt.1 .or. maxbin.lt.1) go to 30
|
||||
lwest = 8*nest+m*4+maxbin*(1+nest+maxbin)
|
||||
kwest = 4*maxtr+2*(maxbin+1)
|
||||
if(lwrk.lt.lwest .or. kwrk.lt.kwest) go to 30
|
||||
if(iopt.gt.0) go to 20
|
||||
if(w(1).le.0.) go to 30
|
||||
if(v(1).gt.0.) v(1) = one
|
||||
if(v(1).lt.0.) v(1) = -one
|
||||
do 10 i=2,m
|
||||
if(x(i-1).ge.x(i) .or. w(i).le.0.) go to 30
|
||||
if(v(i).gt.0.) v(i) = one
|
||||
if(v(i).lt.0.) v(i) = -one
|
||||
10 continue
|
||||
20 ier = 0
|
||||
c we partition the working space and determine the spline approximation
|
||||
ie = 1
|
||||
iw = ie+nest
|
||||
lww = lwrk-nest
|
||||
call fpcoco(iopt,m,x,y,w,v,s,nest,maxtr,maxbin,n,t,c,sq,sx,
|
||||
* bind,wrk(ie),wrk(iw),lww,iwrk,kwrk,ier)
|
||||
30 return
|
||||
end
|
||||
371
cxx/fitpack/concur.f
Normal file
371
cxx/fitpack/concur.f
Normal file
@ -0,0 +1,371 @@
|
||||
recursive subroutine concur(iopt,idim,m,u,mx,x,xx,w,ib,db,nb,
|
||||
* ie,de,ne,k,s,nest,n,t,nc,c,np,cp,fp,wrk,lwrk,iwrk,ier)
|
||||
implicit none
|
||||
c given the ordered set of m points x(i) in the idim-dimensional space
|
||||
c and given also a corresponding set of strictly increasing values u(i)
|
||||
c and the set of positive numbers w(i),i=1,2,...,m, subroutine concur
|
||||
c determines a smooth approximating spline curve s(u), i.e.
|
||||
c x1 = s1(u)
|
||||
c x2 = s2(u) ub = u(1) <= u <= u(m) = ue
|
||||
c .........
|
||||
c xidim = sidim(u)
|
||||
c with sj(u),j=1,2,...,idim spline functions of odd degree k with
|
||||
c common knots t(j),j=1,2,...,n.
|
||||
c in addition these splines will satisfy the following boundary
|
||||
c constraints (l)
|
||||
c if ib > 0 : sj (u(1)) = db(idim*l+j) ,l=0,1,...,ib-1
|
||||
c and (l)
|
||||
c if ie > 0 : sj (u(m)) = de(idim*l+j) ,l=0,1,...,ie-1.
|
||||
c if iopt=-1 concur calculates the weighted least-squares spline curve
|
||||
c according to a given set of knots.
|
||||
c if iopt>=0 the number of knots of the splines sj(u) and the position
|
||||
c t(j),j=1,2,...,n is chosen automatically by the routine. the smooth-
|
||||
c ness of s(u) is then achieved by minimalizing the discontinuity
|
||||
c jumps of the k-th derivative of s(u) at the knots t(j),j=k+2,k+3,...,
|
||||
c n-k-1. the amount of smoothness is determined by the condition that
|
||||
c f(p)=sum((w(i)*dist(x(i),s(u(i))))**2) be <= s, with s a given non-
|
||||
c negative constant, called the smoothing factor.
|
||||
c the fit s(u) is given in the b-spline representation and can be
|
||||
c evaluated by means of subroutine curev.
|
||||
c
|
||||
c calling sequence:
|
||||
c call concur(iopt,idim,m,u,mx,x,xx,w,ib,db,nb,ie,de,ne,k,s,nest,n,
|
||||
c * t,nc,c,np,cp,fp,wrk,lwrk,iwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt : integer flag. on entry iopt must specify whether a weighted
|
||||
c least-squares spline curve (iopt=-1) or a smoothing spline
|
||||
c curve (iopt=0 or 1) must be determined.if iopt=0 the routine
|
||||
c will start with an initial set of knots t(i)=ub,t(i+k+1)=ue,
|
||||
c i=1,2,...,k+1. if iopt=1 the routine will continue with the
|
||||
c knots found at the last call of the routine.
|
||||
c attention: a call with iopt=1 must always be immediately
|
||||
c preceded by another call with iopt=1 or iopt=0.
|
||||
c unchanged on exit.
|
||||
c idim : integer. on entry idim must specify the dimension of the
|
||||
c curve. 0 < idim < 11.
|
||||
c unchanged on exit.
|
||||
c m : integer. on entry m must specify the number of data points.
|
||||
c m > k-max(ib-1,0)-max(ie-1,0). unchanged on exit.
|
||||
c u : real array of dimension at least (m). before entry,
|
||||
c u(i) must be set to the i-th value of the parameter variable
|
||||
c u for i=1,2,...,m. these values must be supplied in
|
||||
c strictly ascending order and will be unchanged on exit.
|
||||
c mx : integer. on entry mx must specify the actual dimension of
|
||||
c the arrays x and xx as declared in the calling (sub)program
|
||||
c mx must not be too small (see x). unchanged on exit.
|
||||
c x : real array of dimension at least idim*m.
|
||||
c before entry, x(idim*(i-1)+j) must contain the j-th coord-
|
||||
c inate of the i-th data point for i=1,2,...,m and j=1,2,...,
|
||||
c idim. unchanged on exit.
|
||||
c xx : real array of dimension at least idim*m.
|
||||
c used as working space. on exit xx contains the coordinates
|
||||
c of the data points to which a spline curve with zero deriv-
|
||||
c ative constraints has been determined.
|
||||
c if the computation mode iopt =1 is used xx should be left
|
||||
c unchanged between calls.
|
||||
c w : real array of dimension at least (m). before entry, w(i)
|
||||
c must be set to the i-th value in the set of weights. the
|
||||
c w(i) must be strictly positive. unchanged on exit.
|
||||
c see also further comments.
|
||||
c ib : integer. on entry ib must specify the number of derivative
|
||||
c constraints for the curve at the begin point. 0<=ib<=(k+1)/2
|
||||
c unchanged on exit.
|
||||
c db : real array of dimension nb. before entry db(idim*l+j) must
|
||||
c contain the l-th order derivative of sj(u) at u=u(1) for
|
||||
c j=1,2,...,idim and l=0,1,...,ib-1 (if ib>0).
|
||||
c unchanged on exit.
|
||||
c nb : integer, specifying the dimension of db. nb>=max(1,idim*ib)
|
||||
c unchanged on exit.
|
||||
c ie : integer. on entry ie must specify the number of derivative
|
||||
c constraints for the curve at the end point. 0<=ie<=(k+1)/2
|
||||
c unchanged on exit.
|
||||
c de : real array of dimension ne. before entry de(idim*l+j) must
|
||||
c contain the l-th order derivative of sj(u) at u=u(m) for
|
||||
c j=1,2,...,idim and l=0,1,...,ie-1 (if ie>0).
|
||||
c unchanged on exit.
|
||||
c ne : integer, specifying the dimension of de. ne>=max(1,idim*ie)
|
||||
c unchanged on exit.
|
||||
c k : integer. on entry k must specify the degree of the splines.
|
||||
c k=1,3 or 5.
|
||||
c unchanged on exit.
|
||||
c s : real.on entry (in case iopt>=0) s must specify the smoothing
|
||||
c factor. s >=0. unchanged on exit.
|
||||
c for advice on the choice of s see further comments.
|
||||
c nest : integer. on entry nest must contain an over-estimate of the
|
||||
c total number of knots of the splines returned, to indicate
|
||||
c the storage space available to the routine. nest >=2*k+2.
|
||||
c in most practical situation nest=m/2 will be sufficient.
|
||||
c always large enough is nest=m+k+1+max(0,ib-1)+max(0,ie-1),
|
||||
c the number of knots needed for interpolation (s=0).
|
||||
c unchanged on exit.
|
||||
c n : integer.
|
||||
c unless ier = 10 (in case iopt >=0), n will contain the
|
||||
c total number of knots of the smoothing spline curve returned
|
||||
c if the computation mode iopt=1 is used this value of n
|
||||
c should be left unchanged between subsequent calls.
|
||||
c in case iopt=-1, the value of n must be specified on entry.
|
||||
c t : real array of dimension at least (nest).
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline curve,i.e. the position of the interior knots t(k+2),
|
||||
c t(k+3),..,t(n-k-1) as well as the position of the additional
|
||||
c t(1)=t(2)=...=t(k+1)=ub and t(n-k)=...=t(n)=ue needed for
|
||||
c the b-spline representation.
|
||||
c if the computation mode iopt=1 is used, the values of t(1),
|
||||
c t(2),...,t(n) should be left unchanged between subsequent
|
||||
c calls. if the computation mode iopt=-1 is used, the values
|
||||
c t(k+2),...,t(n-k-1) must be supplied by the user, before
|
||||
c entry. see also the restrictions (ier=10).
|
||||
c nc : integer. on entry nc must specify the actual dimension of
|
||||
c the array c as declared in the calling (sub)program. nc
|
||||
c must not be too small (see c). unchanged on exit.
|
||||
c c : real array of dimension at least (nest*idim).
|
||||
c on successful exit, this array will contain the coefficients
|
||||
c in the b-spline representation of the spline curve s(u),i.e.
|
||||
c the b-spline coefficients of the spline sj(u) will be given
|
||||
c in c(n*(j-1)+i),i=1,2,...,n-k-1 for j=1,2,...,idim.
|
||||
c cp : real array of dimension at least 2*(k+1)*idim.
|
||||
c on exit cp will contain the b-spline coefficients of a
|
||||
c polynomial curve which satisfies the boundary constraints.
|
||||
c if the computation mode iopt =1 is used cp should be left
|
||||
c unchanged between calls.
|
||||
c np : integer. on entry np must specify the actual dimension of
|
||||
c the array cp as declared in the calling (sub)program. np
|
||||
c must not be too small (see cp). unchanged on exit.
|
||||
c fp : real. unless ier = 10, fp contains the weighted sum of
|
||||
c squared residuals of the spline curve returned.
|
||||
c wrk : real array of dimension at least m*(k+1)+nest*(6+idim+3*k).
|
||||
c used as working space. if the computation mode iopt=1 is
|
||||
c used, the values wrk(1),...,wrk(n) should be left unchanged
|
||||
c between subsequent calls.
|
||||
c lwrk : integer. on entry,lwrk must specify the actual dimension of
|
||||
c the array wrk as declared in the calling (sub)program. lwrk
|
||||
c must not be too small (see wrk). unchanged on exit.
|
||||
c iwrk : integer array of dimension at least (nest).
|
||||
c used as working space. if the computation mode iopt=1 is
|
||||
c used,the values iwrk(1),...,iwrk(n) should be left unchanged
|
||||
c between subsequent calls.
|
||||
c ier : integer. unless the routine detects an error, ier contains a
|
||||
c non-positive value on exit, i.e.
|
||||
c ier=0 : normal return. the curve returned has a residual sum of
|
||||
c squares fp such that abs(fp-s)/s <= tol with tol a relat-
|
||||
c ive tolerance set to 0.001 by the program.
|
||||
c ier=-1 : normal return. the curve returned is an interpolating
|
||||
c spline curve, satisfying the constraints (fp=0).
|
||||
c ier=-2 : normal return. the curve returned is the weighted least-
|
||||
c squares polynomial curve of degree k, satisfying the
|
||||
c constraints. in this extreme case fp gives the upper
|
||||
c bound fp0 for the smoothing factor s.
|
||||
c ier=1 : error. the required storage space exceeds the available
|
||||
c storage space, as specified by the parameter nest.
|
||||
c probably causes : nest too small. if nest is already
|
||||
c large (say nest > m/2), it may also indicate that s is
|
||||
c too small
|
||||
c the approximation returned is the least-squares spline
|
||||
c curve according to the knots t(1),t(2),...,t(n). (n=nest)
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=2 : error. a theoretically impossible result was found during
|
||||
c the iteration process for finding a smoothing spline curve
|
||||
c with fp = s. probably causes : s too small.
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=3 : error. the maximal number of iterations maxit (set to 20
|
||||
c by the program) allowed for finding a smoothing curve
|
||||
c with fp=s has been reached. probably causes : s too small
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=10 : error. on entry, the input data are controlled on validity
|
||||
c the following restrictions must be satisfied.
|
||||
c -1<=iopt<=1, k = 1,3 or 5, m>k-max(0,ib-1)-max(0,ie-1),
|
||||
c nest>=2k+2, 0<idim<=10, lwrk>=(k+1)*m+nest*(6+idim+3*k),
|
||||
c nc >=nest*idim ,u(1)<u(2)<...<u(m),w(i)>0 i=1,2,...,m,
|
||||
c mx>=idim*m,0<=ib<=(k+1)/2,0<=ie<=(k+1)/2,nb>=1,ne>=1,
|
||||
c nb>=ib*idim,ne>=ib*idim,np>=2*(k+1)*idim,
|
||||
c if iopt=-1:2*k+2<=n<=min(nest,mmax) with mmax = m+k+1+
|
||||
c max(0,ib-1)+max(0,ie-1)
|
||||
c u(1)<t(k+2)<t(k+3)<...<t(n-k-1)<u(m)
|
||||
c the schoenberg-whitney conditions, i.e. there
|
||||
c must be a subset of data points uu(j) such that
|
||||
c t(j) < uu(j) < t(j+k+1), j=1+max(0,ib-1),...
|
||||
c ,n+k-1-max(0,ie-1)
|
||||
c if iopt>=0: s>=0
|
||||
c if s=0 : nest >=mmax (see above)
|
||||
c if one of these conditions is found to be violated,control
|
||||
c is immediately repassed to the calling program. in that
|
||||
c case there is no approximation returned.
|
||||
c
|
||||
c further comments:
|
||||
c by means of the parameter s, the user can control the tradeoff
|
||||
c between closeness of fit and smoothness of fit of the approximation.
|
||||
c if s is too large, the curve will be too smooth and signal will be
|
||||
c lost ; if s is too small the curve will pick up too much noise. in
|
||||
c the extreme cases the program will return an interpolating curve if
|
||||
c s=0 and the least-squares polynomial curve of degree k if s is
|
||||
c very large. between these extremes, a properly chosen s will result
|
||||
c in a good compromise between closeness of fit and smoothness of fit.
|
||||
c to decide whether an approximation, corresponding to a certain s is
|
||||
c satisfactory the user is highly recommended to inspect the fits
|
||||
c graphically.
|
||||
c recommended values for s depend on the weights w(i). if these are
|
||||
c taken as 1/d(i) with d(i) an estimate of the standard deviation of
|
||||
c x(i), a good s-value should be found in the range (m-sqrt(2*m),m+
|
||||
c sqrt(2*m)). if nothing is known about the statistical error in x(i)
|
||||
c each w(i) can be set equal to one and s determined by trial and
|
||||
c error, taking account of the comments above. the best is then to
|
||||
c start with a very large value of s ( to determine the least-squares
|
||||
c polynomial curve and the upper bound fp0 for s) and then to
|
||||
c progressively decrease the value of s ( say by a factor 10 in the
|
||||
c beginning, i.e. s=fp0/10, fp0/100,...and more carefully as the
|
||||
c approximating curve shows more detail) to obtain closer fits.
|
||||
c to economize the search for a good s-value the program provides with
|
||||
c different modes of computation. at the first call of the routine, or
|
||||
c whenever he wants to restart with the initial set of knots the user
|
||||
c must set iopt=0.
|
||||
c if iopt=1 the program will continue with the set of knots found at
|
||||
c the last call of the routine. this will save a lot of computation
|
||||
c time if concur is called repeatedly for different values of s.
|
||||
c the number of knots of the spline returned and their location will
|
||||
c depend on the value of s and on the complexity of the shape of the
|
||||
c curve underlying the data. but, if the computation mode iopt=1 is
|
||||
c used, the knots returned may also depend on the s-values at previous
|
||||
c calls (if these were smaller). therefore, if after a number of
|
||||
c trials with different s-values and iopt=1, the user can finally
|
||||
c accept a fit as satisfactory, it may be worthwhile for him to call
|
||||
c concur once more with the selected value for s but now with iopt=0.
|
||||
c indeed, concur may then return an approximation of the same quality
|
||||
c of fit but with fewer knots and therefore better if data reduction
|
||||
c is also an important objective for the user.
|
||||
c
|
||||
c the form of the approximating curve can strongly be affected by
|
||||
c the choice of the parameter values u(i). if there is no physical
|
||||
c reason for choosing a particular parameter u, often good results
|
||||
c will be obtained with the choice
|
||||
c v(1)=0, v(i)=v(i-1)+q(i), i=2,...,m, u(i)=v(i)/v(m), i=1,..,m
|
||||
c where
|
||||
c q(i)= sqrt(sum j=1,idim (xj(i)-xj(i-1))**2 )
|
||||
c other possibilities for q(i) are
|
||||
c q(i)= sum j=1,idim (xj(i)-xj(i-1))**2
|
||||
c q(i)= sum j=1,idim abs(xj(i)-xj(i-1))
|
||||
c q(i)= max j=1,idim abs(xj(i)-xj(i-1))
|
||||
c q(i)= 1
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpback,fpbspl,fpched,fpcons,fpdisc,fpgivs,fpknot,fprati,fprota
|
||||
c curev,fppocu,fpadpo,fpinst
|
||||
c
|
||||
c references:
|
||||
c dierckx p. : algorithms for smoothing data with periodic and
|
||||
c parametric splines, computer graphics and image
|
||||
c processing 20 (1982) 171-184.
|
||||
c dierckx p. : algorithms for smoothing data with periodic and param-
|
||||
c etric splines, report tw55, dept. computer science,
|
||||
c k.u.leuven, 1981.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u. leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : may 1979
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 s,fp
|
||||
integer iopt,idim,m,mx,ib,nb,ie,ne,k,nest,n,nc,np,lwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 u(m),x(mx),xx(mx),db(nb),de(ne),w(m),t(nest),c(nc),wrk(lwrk
|
||||
*)
|
||||
real*8 cp(np)
|
||||
integer iwrk(nest)
|
||||
c ..local scalars..
|
||||
real*8 tol
|
||||
integer i,ib1,ie1,ja,jb,jfp,jg,jq,jz,j,k1,k2,lwest,maxit,nmin,
|
||||
* ncc,kk,mmin,nmax,mxx
|
||||
c ..function references
|
||||
integer max0
|
||||
c ..
|
||||
c we set up the parameters tol and maxit
|
||||
maxit = 20
|
||||
tol = 0.1e-02
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(iopt.lt.(-1) .or. iopt.gt.1) go to 90
|
||||
if(idim.le.0 .or. idim.gt.10) go to 90
|
||||
if(k.le.0 .or. k.gt.5) go to 90
|
||||
k1 = k+1
|
||||
kk = k1/2
|
||||
if(kk*2.ne.k1) go to 90
|
||||
k2 = k1+1
|
||||
if(ib.lt.0 .or. ib.gt.kk) go to 90
|
||||
if(ie.lt.0 .or. ie.gt.kk) go to 90
|
||||
nmin = 2*k1
|
||||
ib1 = max0(0,ib-1)
|
||||
ie1 = max0(0,ie-1)
|
||||
mmin = k1-ib1-ie1
|
||||
if(m.lt.mmin .or. nest.lt.nmin) go to 90
|
||||
if(nb.lt.(idim*ib) .or. ne.lt.(idim*ie)) go to 90
|
||||
if(np.lt.(2*k1*idim)) go to 90
|
||||
mxx = m*idim
|
||||
ncc = nest*idim
|
||||
if(mx.lt.mxx .or. nc.lt.ncc) go to 90
|
||||
lwest = m*k1+nest*(6+idim+3*k)
|
||||
if(lwrk.lt.lwest) go to 90
|
||||
if(w(1).le.0.) go to 90
|
||||
do 10 i=2,m
|
||||
if(u(i-1).ge.u(i) .or. w(i).le.0.) go to 90
|
||||
10 continue
|
||||
if(iopt.ge.0) go to 30
|
||||
if(n.lt.nmin .or. n.gt.nest) go to 90
|
||||
j = n
|
||||
do 20 i=1,k1
|
||||
t(i) = u(1)
|
||||
t(j) = u(m)
|
||||
j = j-1
|
||||
20 continue
|
||||
call fpched(u,m,t,n,k,ib,ie,ier)
|
||||
if (ier.eq.0) go to 40
|
||||
go to 90
|
||||
30 if(s.lt.0.) go to 90
|
||||
nmax = m+k1+ib1+ie1
|
||||
if(s.eq.0. .and. nest.lt.nmax) go to 90
|
||||
ier = 0
|
||||
if(iopt.gt.0) go to 70
|
||||
c we determine a polynomial curve satisfying the boundary constraints.
|
||||
40 call fppocu(idim,k,u(1),u(m),ib,db,nb,ie,de,ne,cp,np)
|
||||
c we generate new data points which will be approximated by a spline
|
||||
c with zero derivative constraints.
|
||||
j = nmin
|
||||
do 50 i=1,k1
|
||||
wrk(i) = u(1)
|
||||
wrk(j) = u(m)
|
||||
j = j-1
|
||||
50 continue
|
||||
c evaluate the polynomial curve
|
||||
call curev(idim,wrk,nmin,cp,np,k,u,m,xx,mxx,ier)
|
||||
c subtract from the old data, the values of the polynomial curve
|
||||
do 60 i=1,mxx
|
||||
xx(i) = x(i)-xx(i)
|
||||
60 continue
|
||||
c we partition the working space and determine the spline curve.
|
||||
70 jfp = 1
|
||||
jz = jfp+nest
|
||||
ja = jz+ncc
|
||||
jb = ja+nest*k1
|
||||
jg = jb+nest*k2
|
||||
jq = jg+nest*k2
|
||||
call fpcons(iopt,idim,m,u,mxx,xx,w,ib,ie,k,s,nest,tol,maxit,k1,
|
||||
* k2,n,t,ncc,c,fp,wrk(jfp),wrk(jz),wrk(ja),wrk(jb),wrk(jg),wrk(jq),
|
||||
*
|
||||
* iwrk,ier)
|
||||
c add the polynomial curve to the calculated spline.
|
||||
call fpadpo(idim,t,n,c,ncc,k,cp,np,wrk(jz),wrk(ja),wrk(jb))
|
||||
90 return
|
||||
end
|
||||
92
cxx/fitpack/cualde.f
Normal file
92
cxx/fitpack/cualde.f
Normal file
@ -0,0 +1,92 @@
|
||||
recursive subroutine cualde(idim,t,n,c,nc,k1,u,d,nd,ier)
|
||||
implicit none
|
||||
c subroutine cualde evaluates at the point u all the derivatives
|
||||
c (l)
|
||||
c d(idim*l+j) = sj (u) ,l=0,1,...,k, j=1,2,...,idim
|
||||
c of a spline curve s(u) of order k1 (degree k=k1-1) and dimension idim
|
||||
c given in its b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c call cualde(idim,t,n,c,nc,k1,u,d,nd,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c idim : integer, giving the dimension of the spline curve.
|
||||
c t : array,length n, which contains the position of the knots.
|
||||
c n : integer, giving the total number of knots of s(u).
|
||||
c c : array,length nc, which contains the b-spline coefficients.
|
||||
c nc : integer, giving the total number of coefficients of s(u).
|
||||
c k1 : integer, giving the order of s(u) (order=degree+1).
|
||||
c u : real, which contains the point where the derivatives must
|
||||
c be evaluated.
|
||||
c nd : integer, giving the dimension of the array d. nd >= k1*idim
|
||||
c
|
||||
c output parameters:
|
||||
c d : array,length nd,giving the different curve derivatives.
|
||||
c d(idim*l+j) will contain the j-th coordinate of the l-th
|
||||
c derivative of the curve at the point u.
|
||||
c ier : error flag
|
||||
c ier = 0 : normal return
|
||||
c ier =10 : invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c nd >= k1*idim
|
||||
c t(k1) <= u <= t(n-k1+1)
|
||||
c
|
||||
c further comments:
|
||||
c if u coincides with a knot, right derivatives are computed
|
||||
c ( left derivatives if u = t(n-k1+1) ).
|
||||
c
|
||||
c other subroutines required: fpader.
|
||||
c
|
||||
c references :
|
||||
c de boor c : on calculating with b-splines, j. approximation theory
|
||||
c 6 (1972) 50-62.
|
||||
c cox m.g. : the numerical evaluation of b-splines, j. inst. maths
|
||||
c applics 10 (1972) 134-149.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer idim,n,nc,k1,nd,ier
|
||||
real*8 u
|
||||
c ..array arguments..
|
||||
real*8 t(n),c(nc),d(nd)
|
||||
c ..local scalars..
|
||||
integer i,j,kk,l,m,nk1
|
||||
c ..local array..
|
||||
real*8 h(6)
|
||||
c ..
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(nd.lt.(k1*idim)) go to 500
|
||||
nk1 = n-k1
|
||||
if(u.lt.t(k1) .or. u.gt.t(nk1+1)) go to 500
|
||||
c search for knot interval t(l) <= u < t(l+1)
|
||||
l = k1
|
||||
100 if(u.lt.t(l+1) .or. l.eq.nk1) go to 200
|
||||
l = l+1
|
||||
go to 100
|
||||
200 if(t(l).ge.t(l+1)) go to 500
|
||||
ier = 0
|
||||
c calculate the derivatives.
|
||||
j = 1
|
||||
do 400 i=1,idim
|
||||
call fpader(t,n,c(j),k1,u,l,h)
|
||||
m = i
|
||||
do 300 kk=1,k1
|
||||
d(m) = h(kk)
|
||||
m = m+idim
|
||||
300 continue
|
||||
j = j+n
|
||||
400 continue
|
||||
500 return
|
||||
end
|
||||
111
cxx/fitpack/curev.f
Normal file
111
cxx/fitpack/curev.f
Normal file
@ -0,0 +1,111 @@
|
||||
recursive subroutine curev(idim,t,n,c,nc,k,u,m,x,mx,ier)
|
||||
implicit none
|
||||
c subroutine curev evaluates in a number of points u(i),i=1,2,...,m
|
||||
c a spline curve s(u) of degree k and dimension idim, given in its
|
||||
c b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c call curev(idim,t,n,c,nc,k,u,m,x,mx,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c idim : integer, giving the dimension of the spline curve.
|
||||
c t : array,length n, which contains the position of the knots.
|
||||
c n : integer, giving the total number of knots of s(u).
|
||||
c c : array,length nc, which contains the b-spline coefficients.
|
||||
c nc : integer, giving the total number of coefficients of s(u).
|
||||
c k : integer, giving the degree of s(u).
|
||||
c u : array,length m, which contains the points where s(u) must
|
||||
c be evaluated.
|
||||
c m : integer, giving the number of points where s(u) must be
|
||||
c evaluated.
|
||||
c mx : integer, giving the dimension of the array x. mx >= m*idim
|
||||
c
|
||||
c output parameters:
|
||||
c x : array,length mx,giving the value of s(u) at the different
|
||||
c points. x(idim*(i-1)+j) will contain the j-th coordinate
|
||||
c of the i-th point on the curve.
|
||||
c ier : error flag
|
||||
c ier = 0 : normal return
|
||||
c ier =10 : invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c m >= 1
|
||||
c mx >= m*idim
|
||||
c t(k+1) <= u(i) <= u(i+1) <= t(n-k) , i=1,2,...,m-1.
|
||||
c
|
||||
c other subroutines required: fpbspl.
|
||||
c
|
||||
c references :
|
||||
c de boor c : on calculating with b-splines, j. approximation theory
|
||||
c 6 (1972) 50-62.
|
||||
c cox m.g. : the numerical evaluation of b-splines, j. inst. maths
|
||||
c applics 10 (1972) 134-149.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer idim,n,nc,k,m,mx,ier
|
||||
c ..array arguments..
|
||||
real*8 t(n),c(nc),u(m),x(mx)
|
||||
c ..local scalars..
|
||||
integer i,j,jj,j1,k1,l,ll,l1,mm,nk1
|
||||
real*8 arg,sp,tb,te
|
||||
c ..local array..
|
||||
real*8 h(6)
|
||||
c ..
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if (m.lt.1) go to 100
|
||||
if (m.eq.1) go to 30
|
||||
go to 10
|
||||
10 do 20 i=2,m
|
||||
if(u(i).lt.u(i-1)) go to 100
|
||||
20 continue
|
||||
30 if(mx.lt.(m*idim)) go to 100
|
||||
ier = 0
|
||||
c fetch tb and te, the boundaries of the approximation interval.
|
||||
k1 = k+1
|
||||
nk1 = n-k1
|
||||
tb = t(k1)
|
||||
te = t(nk1+1)
|
||||
l = k1
|
||||
l1 = l+1
|
||||
c main loop for the different points.
|
||||
mm = 0
|
||||
do 80 i=1,m
|
||||
c fetch a new u-value arg.
|
||||
arg = u(i)
|
||||
if(arg.lt.tb) arg = tb
|
||||
if(arg.gt.te) arg = te
|
||||
c search for knot interval t(l) <= arg < t(l+1)
|
||||
40 if(arg.lt.t(l1) .or. l.eq.nk1) go to 50
|
||||
l = l1
|
||||
l1 = l+1
|
||||
go to 40
|
||||
c evaluate the non-zero b-splines at arg.
|
||||
50 call fpbspl(t,n,k,arg,l,h)
|
||||
c find the value of s(u) at u=arg.
|
||||
ll = l-k1
|
||||
do 70 j1=1,idim
|
||||
jj = ll
|
||||
sp = 0.
|
||||
do 60 j=1,k1
|
||||
jj = jj+1
|
||||
sp = sp+c(jj)*h(j)
|
||||
60 continue
|
||||
mm = mm+1
|
||||
x(mm) = sp
|
||||
ll = ll+n
|
||||
70 continue
|
||||
80 continue
|
||||
100 return
|
||||
end
|
||||
261
cxx/fitpack/curfit.f
Normal file
261
cxx/fitpack/curfit.f
Normal file
@ -0,0 +1,261 @@
|
||||
recursive subroutine curfit(iopt,m,x,y,w,xb,xe,k,s,nest,n,
|
||||
* t,c,fp,wrk,lwrk,iwrk,ier)
|
||||
implicit none
|
||||
c given the set of data points (x(i),y(i)) and the set of positive
|
||||
c numbers w(i),i=1,2,...,m,subroutine curfit determines a smooth spline
|
||||
c approximation of degree k on the interval xb <= x <= xe.
|
||||
c if iopt=-1 curfit calculates the weighted least-squares spline
|
||||
c according to a given set of knots.
|
||||
c if iopt>=0 the number of knots of the spline s(x) and the position
|
||||
c t(j),j=1,2,...,n is chosen automatically by the routine. the smooth-
|
||||
c ness of s(x) is then achieved by minimalizing the discontinuity
|
||||
c jumps of the k-th derivative of s(x) at the knots t(j),j=k+2,k+3,...,
|
||||
c n-k-1. the amount of smoothness is determined by the condition that
|
||||
c f(p)=sum((w(i)*(y(i)-s(x(i))))**2) be <= s, with s a given non-
|
||||
c negative constant, called the smoothing factor.
|
||||
c the fit s(x) is given in the b-spline representation (b-spline coef-
|
||||
c ficients c(j),j=1,2,...,n-k-1) and can be evaluated by means of
|
||||
c subroutine splev.
|
||||
c
|
||||
c calling sequence:
|
||||
c call curfit(iopt,m,x,y,w,xb,xe,k,s,nest,n,t,c,fp,wrk,
|
||||
c * lwrk,iwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt : integer flag. on entry iopt must specify whether a weighted
|
||||
c least-squares spline (iopt=-1) or a smoothing spline (iopt=
|
||||
c 0 or 1) must be determined. if iopt=0 the routine will start
|
||||
c with an initial set of knots t(i)=xb, t(i+k+1)=xe, i=1,2,...
|
||||
c k+1. if iopt=1 the routine will continue with the knots
|
||||
c found at the last call of the routine.
|
||||
c attention: a call with iopt=1 must always be immediately
|
||||
c preceded by another call with iopt=1 or iopt=0.
|
||||
c unchanged on exit.
|
||||
c m : integer. on entry m must specify the number of data points.
|
||||
c m > k. unchanged on exit.
|
||||
c x : real array of dimension at least (m). before entry, x(i)
|
||||
c must be set to the i-th value of the independent variable x,
|
||||
c for i=1,2,...,m. these values must be supplied in strictly
|
||||
c ascending order. unchanged on exit.
|
||||
c y : real array of dimension at least (m). before entry, y(i)
|
||||
c must be set to the i-th value of the dependent variable y,
|
||||
c for i=1,2,...,m. unchanged on exit.
|
||||
c w : real array of dimension at least (m). before entry, w(i)
|
||||
c must be set to the i-th value in the set of weights. the
|
||||
c w(i) must be strictly positive. unchanged on exit.
|
||||
c see also further comments.
|
||||
c xb,xe : real values. on entry xb and xe must specify the boundaries
|
||||
c of the approximation interval. xb<=x(1), xe>=x(m).
|
||||
c unchanged on exit.
|
||||
c k : integer. on entry k must specify the degree of the spline.
|
||||
c 1<=k<=5. it is recommended to use cubic splines (k=3).
|
||||
c the user is strongly dissuaded from choosing k even,together
|
||||
c with a small s-value. unchanged on exit.
|
||||
c s : real.on entry (in case iopt>=0) s must specify the smoothing
|
||||
c factor. s >=0. unchanged on exit.
|
||||
c for advice on the choice of s see further comments.
|
||||
c nest : integer. on entry nest must contain an over-estimate of the
|
||||
c total number of knots of the spline returned, to indicate
|
||||
c the storage space available to the routine. nest >=2*k+2.
|
||||
c in most practical situation nest=m/2 will be sufficient.
|
||||
c always large enough is nest=m+k+1, the number of knots
|
||||
c needed for interpolation (s=0). unchanged on exit.
|
||||
c n : integer.
|
||||
c unless ier =10 (in case iopt >=0), n will contain the
|
||||
c total number of knots of the spline approximation returned.
|
||||
c if the computation mode iopt=1 is used this value of n
|
||||
c should be left unchanged between subsequent calls.
|
||||
c in case iopt=-1, the value of n must be specified on entry.
|
||||
c t : real array of dimension at least (nest).
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline,i.e. the position of the interior knots t(k+2),t(k+3)
|
||||
c ...,t(n-k-1) as well as the position of the additional knots
|
||||
c t(1)=t(2)=...=t(k+1)=xb and t(n-k)=...=t(n)=xe needed for
|
||||
c the b-spline representation.
|
||||
c if the computation mode iopt=1 is used, the values of t(1),
|
||||
c t(2),...,t(n) should be left unchanged between subsequent
|
||||
c calls. if the computation mode iopt=-1 is used, the values
|
||||
c t(k+2),...,t(n-k-1) must be supplied by the user, before
|
||||
c entry. see also the restrictions (ier=10).
|
||||
c c : real array of dimension at least (nest).
|
||||
c on successful exit, this array will contain the coefficients
|
||||
c c(1),c(2),..,c(n-k-1) in the b-spline representation of s(x)
|
||||
c fp : real. unless ier=10, fp contains the weighted sum of
|
||||
c squared residuals of the spline approximation returned.
|
||||
c wrk : real array of dimension at least (m*(k+1)+nest*(7+3*k)).
|
||||
c used as working space. if the computation mode iopt=1 is
|
||||
c used, the values wrk(1),...,wrk(n) should be left unchanged
|
||||
c between subsequent calls.
|
||||
c lwrk : integer. on entry,lwrk must specify the actual dimension of
|
||||
c the array wrk as declared in the calling (sub)program.lwrk
|
||||
c must not be too small (see wrk). unchanged on exit.
|
||||
c iwrk : integer array of dimension at least (nest).
|
||||
c used as working space. if the computation mode iopt=1 is
|
||||
c used,the values iwrk(1),...,iwrk(n) should be left unchanged
|
||||
c between subsequent calls.
|
||||
c ier : integer. unless the routine detects an error, ier contains a
|
||||
c non-positive value on exit, i.e.
|
||||
c ier=0 : normal return. the spline returned has a residual sum of
|
||||
c squares fp such that abs(fp-s)/s <= tol with tol a relat-
|
||||
c ive tolerance set to 0.001 by the program.
|
||||
c ier=-1 : normal return. the spline returned is an interpolating
|
||||
c spline (fp=0).
|
||||
c ier=-2 : normal return. the spline returned is the weighted least-
|
||||
c squares polynomial of degree k. in this extreme case fp
|
||||
c gives the upper bound fp0 for the smoothing factor s.
|
||||
c ier=1 : error. the required storage space exceeds the available
|
||||
c storage space, as specified by the parameter nest.
|
||||
c probably causes : nest too small. if nest is already
|
||||
c large (say nest > m/2), it may also indicate that s is
|
||||
c too small
|
||||
c the approximation returned is the weighted least-squares
|
||||
c spline according to the knots t(1),t(2),...,t(n). (n=nest)
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=2 : error. a theoretically impossible result was found during
|
||||
c the iteration process for finding a smoothing spline with
|
||||
c fp = s. probably causes : s too small.
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=3 : error. the maximal number of iterations maxit (set to 20
|
||||
c by the program) allowed for finding a smoothing spline
|
||||
c with fp=s has been reached. probably causes : s too small
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=10 : error. on entry, the input data are controlled on validity
|
||||
c the following restrictions must be satisfied.
|
||||
c -1<=iopt<=1, 1<=k<=5, m>k, nest>2*k+2, w(i)>0,i=1,2,...,m
|
||||
c xb<=x(1)<x(2)<...<x(m)<=xe, lwrk>=(k+1)*m+nest*(7+3*k)
|
||||
c if iopt=-1: 2*k+2<=n<=min(nest,m+k+1)
|
||||
c xb<t(k+2)<t(k+3)<...<t(n-k-1)<xe
|
||||
c the schoenberg-whitney conditions, i.e. there
|
||||
c must be a subset of data points xx(j) such that
|
||||
c t(j) < xx(j) < t(j+k+1), j=1,2,...,n-k-1
|
||||
c if iopt>=0: s>=0
|
||||
c if s=0 : nest >= m+k+1
|
||||
c if one of these conditions is found to be violated,control
|
||||
c is immediately repassed to the calling program. in that
|
||||
c case there is no approximation returned.
|
||||
c
|
||||
c further comments:
|
||||
c by means of the parameter s, the user can control the tradeoff
|
||||
c between closeness of fit and smoothness of fit of the approximation.
|
||||
c if s is too large, the spline will be too smooth and signal will be
|
||||
c lost ; if s is too small the spline will pick up too much noise. in
|
||||
c the extreme cases the program will return an interpolating spline if
|
||||
c s=0 and the weighted least-squares polynomial of degree k if s is
|
||||
c very large. between these extremes, a properly chosen s will result
|
||||
c in a good compromise between closeness of fit and smoothness of fit.
|
||||
c to decide whether an approximation, corresponding to a certain s is
|
||||
c satisfactory the user is highly recommended to inspect the fits
|
||||
c graphically.
|
||||
c recommended values for s depend on the weights w(i). if these are
|
||||
c taken as 1/d(i) with d(i) an estimate of the standard deviation of
|
||||
c y(i), a good s-value should be found in the range (m-sqrt(2*m),m+
|
||||
c sqrt(2*m)). if nothing is known about the statistical error in y(i)
|
||||
c each w(i) can be set equal to one and s determined by trial and
|
||||
c error, taking account of the comments above. the best is then to
|
||||
c start with a very large value of s ( to determine the least-squares
|
||||
c polynomial and the corresponding upper bound fp0 for s) and then to
|
||||
c progressively decrease the value of s ( say by a factor 10 in the
|
||||
c beginning, i.e. s=fp0/10, fp0/100,...and more carefully as the
|
||||
c approximation shows more detail) to obtain closer fits.
|
||||
c to economize the search for a good s-value the program provides with
|
||||
c different modes of computation. at the first call of the routine, or
|
||||
c whenever he wants to restart with the initial set of knots the user
|
||||
c must set iopt=0.
|
||||
c if iopt=1 the program will continue with the set of knots found at
|
||||
c the last call of the routine. this will save a lot of computation
|
||||
c time if curfit is called repeatedly for different values of s.
|
||||
c the number of knots of the spline returned and their location will
|
||||
c depend on the value of s and on the complexity of the shape of the
|
||||
c function underlying the data. but, if the computation mode iopt=1
|
||||
c is used, the knots returned may also depend on the s-values at
|
||||
c previous calls (if these were smaller). therefore, if after a number
|
||||
c of trials with different s-values and iopt=1, the user can finally
|
||||
c accept a fit as satisfactory, it may be worthwhile for him to call
|
||||
c curfit once more with the selected value for s but now with iopt=0.
|
||||
c indeed, curfit may then return an approximation of the same quality
|
||||
c of fit but with fewer knots and therefore better if data reduction
|
||||
c is also an important objective for the user.
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpback,fpbspl,fpchec,fpcurf,fpdisc,fpgivs,fpknot,fprati,fprota
|
||||
c
|
||||
c references:
|
||||
c dierckx p. : an algorithm for smoothing, differentiation and integ-
|
||||
c ration of experimental data using spline functions,
|
||||
c j.comp.appl.maths 1 (1975) 165-184.
|
||||
c dierckx p. : a fast algorithm for smoothing data on a rectangular
|
||||
c grid while using spline functions, siam j.numer.anal.
|
||||
c 19 (1982) 1286-1304.
|
||||
c dierckx p. : an improved algorithm for curve fitting with spline
|
||||
c functions, report tw54, dept. computer science,k.u.
|
||||
c leuven, 1981.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u. leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : may 1979
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 xb,xe,s,fp
|
||||
integer iopt,m,k,nest,n,lwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),y(m),w(m),t(nest),c(nest),wrk(lwrk)
|
||||
integer iwrk(nest)
|
||||
c ..local scalars..
|
||||
real*8 tol
|
||||
integer i,ia,ib,ifp,ig,iq,iz,j,k1,k2,lwest,maxit,nmin
|
||||
c ..
|
||||
c we set up the parameters tol and maxit
|
||||
maxit = 20
|
||||
tol = 0.1d-02
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(k.le.0 .or. k.gt.5) go to 50
|
||||
k1 = k+1
|
||||
k2 = k1+1
|
||||
if(iopt.lt.(-1) .or. iopt.gt.1) go to 50
|
||||
nmin = 2*k1
|
||||
if(m.lt.k1 .or. nest.lt.nmin) go to 50
|
||||
lwest = m*k1+nest*(7+3*k)
|
||||
if(lwrk.lt.lwest) go to 50
|
||||
if(xb.gt.x(1) .or. xe.lt.x(m)) go to 50
|
||||
do 10 i=2,m
|
||||
if(x(i-1).gt.x(i)) go to 50
|
||||
10 continue
|
||||
if(iopt.ge.0) go to 30
|
||||
if(n.lt.nmin .or. n.gt.nest) go to 50
|
||||
j = n
|
||||
do 20 i=1,k1
|
||||
t(i) = xb
|
||||
t(j) = xe
|
||||
j = j-1
|
||||
20 continue
|
||||
call fpchec(x,m,t,n,k,ier)
|
||||
if (ier.eq.0) go to 40
|
||||
go to 50
|
||||
30 if(s.lt.0.) go to 50
|
||||
if(s.eq.0. .and. nest.lt.(m+k1)) go to 50
|
||||
c we partition the working space and determine the spline approximation.
|
||||
40 ifp = 1
|
||||
iz = ifp+nest
|
||||
ia = iz+nest
|
||||
ib = ia+nest*k1
|
||||
ig = ib+nest*k2
|
||||
iq = ig+nest*k2
|
||||
call fpcurf(iopt,x,y,w,m,xb,xe,k,s,nest,tol,maxit,k1,k2,n,t,c,fp,
|
||||
* wrk(ifp),wrk(iz),wrk(ia),wrk(ib),wrk(ig),wrk(iq),iwrk,ier)
|
||||
50 return
|
||||
end
|
||||
91
cxx/fitpack/dblint.f
Normal file
91
cxx/fitpack/dblint.f
Normal file
@ -0,0 +1,91 @@
|
||||
recursive function dblint(tx,nx,ty,ny,c,kx,ky,xb,xe,yb,
|
||||
* ye,wrk) result(dblint_res)
|
||||
implicit none
|
||||
real*8 :: dblint_res
|
||||
c function dblint calculates the double integral
|
||||
c / xe / ye
|
||||
c | | s(x,y) dx dy
|
||||
c xb / yb /
|
||||
c with s(x,y) a bivariate spline of degrees kx and ky, given in the
|
||||
c b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c aint = dblint(tx,nx,ty,ny,c,kx,ky,xb,xe,yb,ye,wrk)
|
||||
c
|
||||
c input parameters:
|
||||
c tx : real array, length nx, which contains the position of the
|
||||
c knots in the x-direction.
|
||||
c nx : integer, giving the total number of knots in the x-direction
|
||||
c ty : real array, length ny, which contains the position of the
|
||||
c knots in the y-direction.
|
||||
c ny : integer, giving the total number of knots in the y-direction
|
||||
c c : real array, length (nx-kx-1)*(ny-ky-1), which contains the
|
||||
c b-spline coefficients.
|
||||
c kx,ky : integer values, giving the degrees of the spline.
|
||||
c xb,xe : real values, containing the boundaries of the integration
|
||||
c yb,ye domain. s(x,y) is considered to be identically zero out-
|
||||
c side the rectangle (tx(kx+1),tx(nx-kx))*(ty(ky+1),ty(ny-ky))
|
||||
c
|
||||
c output parameters:
|
||||
c aint : real , containing the double integral of s(x,y).
|
||||
c wrk : real array of dimension at least (nx+ny-kx-ky-2).
|
||||
c used as working space.
|
||||
c on exit, wrk(i) will contain the integral
|
||||
c / xe
|
||||
c | ni,kx+1(x) dx , i=1,2,...,nx-kx-1
|
||||
c xb /
|
||||
c with ni,kx+1(x) the normalized b-spline defined on
|
||||
c the knots tx(i),...,tx(i+kx+1)
|
||||
c wrk(j+nx-kx-1) will contain the integral
|
||||
c / ye
|
||||
c | nj,ky+1(y) dy , j=1,2,...,ny-ky-1
|
||||
c yb /
|
||||
c with nj,ky+1(y) the normalized b-spline defined on
|
||||
c the knots ty(j),...,ty(j+ky+1)
|
||||
c
|
||||
c other subroutines required: fpintb
|
||||
c
|
||||
c references :
|
||||
c gaffney p.w. : the calculation of indefinite integrals of b-splines
|
||||
c j. inst. maths applics 17 (1976) 37-41.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1989
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer nx,ny,kx,ky
|
||||
real*8 xb,xe,yb,ye
|
||||
c ..array arguments..
|
||||
real*8 tx(nx),ty(ny),c((nx-kx-1)*(ny-ky-1)),wrk(nx+ny-kx-ky-2)
|
||||
c ..local scalars..
|
||||
integer i,j,l,m,nkx1,nky1
|
||||
real*8 res
|
||||
c ..
|
||||
nkx1 = nx-kx-1
|
||||
nky1 = ny-ky-1
|
||||
c we calculate the integrals of the normalized b-splines ni,kx+1(x)
|
||||
call fpintb(tx,nx,wrk,nkx1,xb,xe)
|
||||
c we calculate the integrals of the normalized b-splines nj,ky+1(y)
|
||||
call fpintb(ty,ny,wrk(nkx1+1),nky1,yb,ye)
|
||||
c calculate the integral of s(x,y)
|
||||
dblint_res = 0.
|
||||
do 200 i=1,nkx1
|
||||
res = wrk(i)
|
||||
if(res.eq.0.) go to 200
|
||||
m = (i-1)*nky1
|
||||
l = nkx1
|
||||
do 100 j=1,nky1
|
||||
m = m+1
|
||||
l = l+1
|
||||
dblint_res = dblint_res + res*wrk(l)*c(m)
|
||||
100 continue
|
||||
200 continue
|
||||
return
|
||||
end
|
||||
84
cxx/fitpack/evapol.f
Normal file
84
cxx/fitpack/evapol.f
Normal file
@ -0,0 +1,84 @@
|
||||
recursive function evapol(tu,nu,tv,nv,c,rad,x,y) result(e_res)
|
||||
implicit none
|
||||
real*8 :: e_res
|
||||
c function program evacir evaluates the function f(x,y) = s(u,v),
|
||||
c defined through the transformation
|
||||
c x = u*rad(v)*cos(v) y = u*rad(v)*sin(v)
|
||||
c and where s(u,v) is a bicubic spline ( 0<=u<=1 , -pi<=v<=pi ), given
|
||||
c in its standard b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c f = evapol(tu,nu,tv,nv,c,rad,x,y)
|
||||
c
|
||||
c input parameters:
|
||||
c tu : real array, length nu, which contains the position of the
|
||||
c knots in the u-direction.
|
||||
c nu : integer, giving the total number of knots in the u-direction
|
||||
c tv : real array, length nv, which contains the position of the
|
||||
c knots in the v-direction.
|
||||
c nv : integer, giving the total number of knots in the v-direction
|
||||
c c : real array, length (nu-4)*(nv-4), which contains the
|
||||
c b-spline coefficients.
|
||||
c rad : real function subprogram, defining the boundary of the
|
||||
c approximation domain. must be declared external in the
|
||||
c calling (sub)-program
|
||||
c x,y : real values.
|
||||
c before entry x and y must be set to the co-ordinates of
|
||||
c the point where f(x,y) must be evaluated.
|
||||
c
|
||||
c output parameter:
|
||||
c f : real
|
||||
c on exit f contains the value of f(x,y)
|
||||
c
|
||||
c other subroutines required:
|
||||
c bispev,fpbisp,fpbspl
|
||||
c
|
||||
c references :
|
||||
c de boor c : on calculating with b-splines, j. approximation theory
|
||||
c 6 (1972) 50-62.
|
||||
c cox m.g. : the numerical evaluation of b-splines, j. inst. maths
|
||||
c applics 10 (1972) 134-149.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1989
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer nu,nv
|
||||
real*8 x,y
|
||||
c ..array arguments..
|
||||
real*8 tu(nu),tv(nv),c((nu-4)*(nv-4))
|
||||
c ..user specified function
|
||||
real*8 rad
|
||||
c ..local scalars..
|
||||
integer ier
|
||||
real*8 u,v,r,f,one,dist
|
||||
c ..local arrays
|
||||
real*8 wrk(8)
|
||||
integer iwrk(2)
|
||||
c ..function references
|
||||
real*8 atan2,sqrt
|
||||
c ..
|
||||
c calculate the (u,v)-coordinates of the given point.
|
||||
one = 1
|
||||
u = 0.
|
||||
v = 0.
|
||||
dist = x**2+y**2
|
||||
if(dist.le.0.) go to 10
|
||||
v = atan2(y,x)
|
||||
r = rad(v)
|
||||
if(r.le.0.) go to 10
|
||||
u = sqrt(dist)/r
|
||||
if(u.gt.one) u = one
|
||||
c evaluate s(u,v)
|
||||
10 call bispev(tu,nu,tv,nv,c,3,3,u,1,v,1,f,wrk,8,iwrk,2,ier)
|
||||
e_res = f
|
||||
return
|
||||
end
|
||||
|
||||
134
cxx/fitpack/fitpack.h
Normal file
134
cxx/fitpack/fitpack.h
Normal file
@ -0,0 +1,134 @@
|
||||
#pragma once
|
||||
|
||||
#include <ranges>
|
||||
|
||||
namespace mcc::fitpack
|
||||
{
|
||||
|
||||
extern "C" {
|
||||
void curfit(int* iopt,
|
||||
int* m,
|
||||
double* x,
|
||||
double* y,
|
||||
double* w,
|
||||
double* xb,
|
||||
double* xe,
|
||||
int* k,
|
||||
double* s,
|
||||
int* nest,
|
||||
int* n,
|
||||
double* t,
|
||||
double* c,
|
||||
double* fp,
|
||||
double* wrk,
|
||||
int* lwrk,
|
||||
int* iwrk,
|
||||
int* ier);
|
||||
|
||||
void splev(double* t, int* n, double* c, int* k, double* x, double* y, int* m, int* e, int* ier);
|
||||
|
||||
void splder(double* t, int* n, double* c, int* k, int* nu, double* x, double* y, int* m, int* e, double* wrk, int* ier);
|
||||
|
||||
void surfit(int* iopt,
|
||||
int* m,
|
||||
double* x,
|
||||
double* y,
|
||||
double* z,
|
||||
double* w,
|
||||
double* xb,
|
||||
double* xe,
|
||||
double* yb,
|
||||
double* ye,
|
||||
int* kx,
|
||||
int* ky,
|
||||
double* s,
|
||||
int* nxest,
|
||||
int* nyest,
|
||||
int* nmax,
|
||||
double* eps,
|
||||
int* nx,
|
||||
double* tx,
|
||||
int* ny,
|
||||
double* ty,
|
||||
double* c,
|
||||
double* fp,
|
||||
double* wrk1,
|
||||
int* lwrk1,
|
||||
double* wrk2,
|
||||
int* lwrk2,
|
||||
int* iwrk,
|
||||
int* kwrk,
|
||||
int* ier);
|
||||
|
||||
void bispev(double* tx,
|
||||
int* nx,
|
||||
double* ty,
|
||||
int* ny,
|
||||
double* c,
|
||||
int* kx,
|
||||
int* ky,
|
||||
double* x,
|
||||
int* mx,
|
||||
double* y,
|
||||
int* my,
|
||||
double* z,
|
||||
double* wrk,
|
||||
int* lwrk,
|
||||
int* iwrk,
|
||||
int* kwrk,
|
||||
int* ier);
|
||||
|
||||
void parder(double* tx,
|
||||
int* nx,
|
||||
double* ty,
|
||||
int* ny,
|
||||
double* c,
|
||||
int* kx,
|
||||
int* ky,
|
||||
int* nux,
|
||||
int* nuy,
|
||||
double* x,
|
||||
int* mx,
|
||||
double* y,
|
||||
int* my,
|
||||
double* z,
|
||||
double* wrk,
|
||||
int* lwrk,
|
||||
int* iwrk,
|
||||
int* kwrk,
|
||||
int* ier);
|
||||
|
||||
|
||||
void sphere(int* iopt,
|
||||
int* m,
|
||||
double* teta,
|
||||
double* phi,
|
||||
double* r,
|
||||
double* w,
|
||||
double* s,
|
||||
int* ntest,
|
||||
int* npest,
|
||||
double* eps,
|
||||
int* nt,
|
||||
double* tt,
|
||||
int* np,
|
||||
double* tp,
|
||||
double* c,
|
||||
double* fp,
|
||||
double* wrk1,
|
||||
int* lwrk1,
|
||||
double* wrk2,
|
||||
int* lwrk2,
|
||||
int* iwrk,
|
||||
int* kwrk,
|
||||
int* ier);
|
||||
}
|
||||
|
||||
|
||||
template <std::ranges::input_range TethaT, std::ranges::input_range PhiT>
|
||||
int fitpack_sphere(const TethaT& tetha, const PhiT& phi)
|
||||
{
|
||||
}
|
||||
|
||||
|
||||
} // namespace mcc::fitpack
|
||||
97
cxx/fitpack/fourco.f
Normal file
97
cxx/fitpack/fourco.f
Normal file
@ -0,0 +1,97 @@
|
||||
recursive subroutine fourco(t,n,c,alfa,m,ress,resc,wrk1,wrk2,ier)
|
||||
implicit none
|
||||
c subroutine fourco calculates the integrals
|
||||
c /t(n-3)
|
||||
c ress(i) = ! s(x)*sin(alfa(i)*x) dx and
|
||||
c t(4)/
|
||||
c /t(n-3)
|
||||
c resc(i) = ! s(x)*cos(alfa(i)*x) dx, i=1,...,m,
|
||||
c t(4)/
|
||||
c where s(x) denotes a cubic spline which is given in its
|
||||
c b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c call fourco(t,n,c,alfa,m,ress,resc,wrk1,wrk2,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c t : real array,length n, containing the knots of s(x).
|
||||
c n : integer, containing the total number of knots. n>=10.
|
||||
c c : real array,length n, containing the b-spline coefficients.
|
||||
c alfa : real array,length m, containing the parameters alfa(i).
|
||||
c m : integer, specifying the number of integrals to be computed.
|
||||
c wrk1 : real array,length n. used as working space
|
||||
c wrk2 : real array,length n. used as working space
|
||||
c
|
||||
c output parameters:
|
||||
c ress : real array,length m, containing the integrals ress(i).
|
||||
c resc : real array,length m, containing the integrals resc(i).
|
||||
c ier : error flag:
|
||||
c ier=0 : normal return.
|
||||
c ier=10: invalid input data (see restrictions).
|
||||
c
|
||||
c restrictions:
|
||||
c n >= 10
|
||||
c t(4) < t(5) < ... < t(n-4) < t(n-3).
|
||||
c t(1) <= t(2) <= t(3) <= t(4).
|
||||
c t(n-3) <= t(n-2) <= t(n-1) <= t(n).
|
||||
c
|
||||
c other subroutines required: fpbfou,fpcsin
|
||||
c
|
||||
c references :
|
||||
c dierckx p. : calculation of fouriercoefficients of discrete
|
||||
c functions using cubic splines. j. computational
|
||||
c and applied mathematics 3 (1977) 207-209.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer n,m,ier
|
||||
c ..array arguments..
|
||||
real*8 t(n),c(n),wrk1(n),wrk2(n),alfa(m),ress(m),resc(m)
|
||||
c ..local scalars..
|
||||
integer i,j,n4
|
||||
real*8 rs,rc
|
||||
c ..
|
||||
n4 = n-4
|
||||
c before starting computations a data check is made. in the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(n.lt.10) go to 50
|
||||
j = n
|
||||
do 10 i=1,3
|
||||
if(t(i).gt.t(i+1)) go to 50
|
||||
if(t(j).lt.t(j-1)) go to 50
|
||||
j = j-1
|
||||
10 continue
|
||||
do 20 i=4,n4
|
||||
if(t(i).ge.t(i+1)) go to 50
|
||||
20 continue
|
||||
ier = 0
|
||||
c main loop for the different alfa(i).
|
||||
do 40 i=1,m
|
||||
c calculate the integrals
|
||||
c wrk1(j) = integral(nj,4(x)*sin(alfa*x)) and
|
||||
c wrk2(j) = integral(nj,4(x)*cos(alfa*x)), j=1,2,...,n-4,
|
||||
c where nj,4(x) denotes the normalised cubic b-spline defined on the
|
||||
c knots t(j),t(j+1),...,t(j+4).
|
||||
call fpbfou(t,n,alfa(i),wrk1,wrk2)
|
||||
c calculate the integrals ress(i) and resc(i).
|
||||
rs = 0.
|
||||
rc = 0.
|
||||
do 30 j=1,n4
|
||||
rs = rs+c(j)*wrk1(j)
|
||||
rc = rc+c(j)*wrk2(j)
|
||||
30 continue
|
||||
ress(i) = rs
|
||||
resc(i) = rc
|
||||
40 continue
|
||||
50 return
|
||||
end
|
||||
57
cxx/fitpack/fpader.f
Normal file
57
cxx/fitpack/fpader.f
Normal file
@ -0,0 +1,57 @@
|
||||
recursive subroutine fpader(t,n,c,k1,x,l,d)
|
||||
c subroutine fpader calculates the derivatives
|
||||
c (j-1)
|
||||
c d(j) = s (x) , j=1,2,...,k1
|
||||
c of a spline of order k1 at the point t(l)<=x<t(l+1), using the
|
||||
c stable recurrence scheme of de boor
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 x
|
||||
integer n,k1,l
|
||||
c ..array arguments..
|
||||
real*8 t(n),c(n),d(k1)
|
||||
c ..local scalars..
|
||||
integer i,ik,j,jj,j1,j2,ki,kj,li,lj,lk
|
||||
real*8 ak,fac,one
|
||||
c ..local array..
|
||||
real*8 h(20)
|
||||
c ..
|
||||
one = 0.1d+01
|
||||
lk = l-k1
|
||||
do 100 i=1,k1
|
||||
ik = i+lk
|
||||
h(i) = c(ik)
|
||||
100 continue
|
||||
kj = k1
|
||||
fac = one
|
||||
do 700 j=1,k1
|
||||
ki = kj
|
||||
j1 = j+1
|
||||
if(j.eq.1) go to 300
|
||||
i = k1
|
||||
do 200 jj=j,k1
|
||||
li = i+lk
|
||||
lj = li+kj
|
||||
h(i) = (h(i)-h(i-1))/(t(lj)-t(li))
|
||||
i = i-1
|
||||
200 continue
|
||||
300 do 400 i=j,k1
|
||||
d(i) = h(i)
|
||||
400 continue
|
||||
if(j.eq.k1) go to 600
|
||||
do 500 jj=j1,k1
|
||||
ki = ki-1
|
||||
i = k1
|
||||
do 500 j2=jj,k1
|
||||
li = i+lk
|
||||
lj = li+ki
|
||||
d(i) = ((x-t(li))*d(i)+(t(lj)-x)*d(i-1))/(t(lj)-t(li))
|
||||
i = i-1
|
||||
500 continue
|
||||
600 d(j) = d(k1)*fac
|
||||
ak = k1-j
|
||||
fac = fac*ak
|
||||
kj = kj-1
|
||||
700 continue
|
||||
return
|
||||
end
|
||||
60
cxx/fitpack/fpadno.f
Normal file
60
cxx/fitpack/fpadno.f
Normal file
@ -0,0 +1,60 @@
|
||||
recursive subroutine fpadno(maxtr,up,left,right,info,count,
|
||||
* merk,jbind,n1,ier)
|
||||
implicit none
|
||||
c subroutine fpadno adds a branch of length n1 to the triply linked
|
||||
c tree,the information of which is kept in the arrays up,left,right
|
||||
c and info. the information field of the nodes of this new branch is
|
||||
c given in the array jbind. in linking the new branch fpadno takes
|
||||
c account of the property of the tree that
|
||||
c info(k) < info(right(k)) ; info(k) < info(left(k))
|
||||
c if necessary the subroutine calls subroutine fpfrno to collect the
|
||||
c free nodes of the tree. if no computer words are available at that
|
||||
c moment, the error parameter ier is set to 1.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer maxtr,count,merk,n1,ier
|
||||
c ..array arguments..
|
||||
integer up(maxtr),left(maxtr),right(maxtr),info(maxtr),jbind(n1)
|
||||
c ..local scalars..
|
||||
integer k,niveau,point
|
||||
logical bool
|
||||
c ..subroutine references..
|
||||
c fpfrno
|
||||
c ..
|
||||
point = 1
|
||||
niveau = 1
|
||||
10 k = left(point)
|
||||
bool = .true.
|
||||
20 if(k.eq.0) go to 50
|
||||
if (info(k)-jbind(niveau).lt.0) go to 30
|
||||
if (info(k)-jbind(niveau).eq.0) go to 40
|
||||
go to 50
|
||||
30 point = k
|
||||
k = right(point)
|
||||
bool = .false.
|
||||
go to 20
|
||||
40 point = k
|
||||
niveau = niveau+1
|
||||
go to 10
|
||||
50 if(niveau.gt.n1) go to 90
|
||||
count = count+1
|
||||
if(count.le.maxtr) go to 60
|
||||
call fpfrno(maxtr,up,left,right,info,point,merk,n1,count,ier)
|
||||
if(ier.ne.0) go to 100
|
||||
60 info(count) = jbind(niveau)
|
||||
left(count) = 0
|
||||
right(count) = k
|
||||
if(bool) go to 70
|
||||
bool = .true.
|
||||
right(point) = count
|
||||
up(count) = up(point)
|
||||
go to 80
|
||||
70 up(count) = point
|
||||
left(point) = count
|
||||
80 point = count
|
||||
niveau = niveau+1
|
||||
k = 0
|
||||
go to 50
|
||||
90 ier = 0
|
||||
100 return
|
||||
end
|
||||
71
cxx/fitpack/fpadpo.f
Normal file
71
cxx/fitpack/fpadpo.f
Normal file
@ -0,0 +1,71 @@
|
||||
recursive subroutine fpadpo(idim,t,n,c,nc,k,cp,np,cc,t1,t2)
|
||||
implicit none
|
||||
c given a idim-dimensional spline curve of degree k, in its b-spline
|
||||
c representation ( knots t(j),j=1,...,n , b-spline coefficients c(j),
|
||||
c j=1,...,nc) and given also a polynomial curve in its b-spline
|
||||
c representation ( coefficients cp(j), j=1,...,np), subroutine fpadpo
|
||||
c calculates the b-spline representation (coefficients c(j),j=1,...,nc)
|
||||
c of the sum of the two curves.
|
||||
c
|
||||
c other subroutine required : fpinst
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer idim,k,n,nc,np
|
||||
c ..array arguments..
|
||||
real*8 t(n),c(nc),cp(np),cc(nc),t1(n),t2(n)
|
||||
c ..local scalars..
|
||||
integer i,ii,j,jj,k1,l,l1,n1,n2,nk1,nk2
|
||||
c ..
|
||||
k1 = k+1
|
||||
nk1 = n-k1
|
||||
c initialization
|
||||
j = 1
|
||||
l = 1
|
||||
do 20 jj=1,idim
|
||||
l1 = j
|
||||
do 10 ii=1,k1
|
||||
cc(l1) = cp(l)
|
||||
l1 = l1+1
|
||||
l = l+1
|
||||
10 continue
|
||||
j = j+n
|
||||
l = l+k1
|
||||
20 continue
|
||||
if(nk1.eq.k1) go to 70
|
||||
n1 = k1*2
|
||||
j = n
|
||||
l = n1
|
||||
do 30 i=1,k1
|
||||
t1(i) = t(i)
|
||||
t1(l) = t(j)
|
||||
l = l-1
|
||||
j = j-1
|
||||
30 continue
|
||||
c find the b-spline representation of the given polynomial curve
|
||||
c according to the given set of knots.
|
||||
nk2 = nk1-1
|
||||
do 60 l=k1,nk2
|
||||
l1 = l+1
|
||||
j = 1
|
||||
do 40 i=1,idim
|
||||
call fpinst(0,t1,n1,cc(j),k,t(l1),l,t2,n2,cc(j),n)
|
||||
j = j+n
|
||||
40 continue
|
||||
do 50 i=1,n2
|
||||
t1(i) = t2(i)
|
||||
50 continue
|
||||
n1 = n2
|
||||
60 continue
|
||||
c find the b-spline representation of the resulting curve.
|
||||
70 j = 1
|
||||
do 90 jj=1,idim
|
||||
l = j
|
||||
do 80 i=1,nk1
|
||||
c(l) = cc(l)+c(l)
|
||||
l = l+1
|
||||
80 continue
|
||||
j = j+n
|
||||
90 continue
|
||||
return
|
||||
end
|
||||
32
cxx/fitpack/fpback.f
Normal file
32
cxx/fitpack/fpback.f
Normal file
@ -0,0 +1,32 @@
|
||||
recursive subroutine fpback(a,z,n,k,c,nest)
|
||||
implicit none
|
||||
c subroutine fpback calculates the solution of the system of
|
||||
c equations a*c = z with a a n x n upper triangular matrix
|
||||
c of bandwidth k.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer n,k,nest
|
||||
c ..array arguments..
|
||||
real*8 a(nest,k),z(n),c(n)
|
||||
c ..local scalars..
|
||||
real*8 store
|
||||
integer i,i1,j,k1,l,m
|
||||
c ..
|
||||
k1 = k-1
|
||||
c(n) = z(n)/a(n,1)
|
||||
i = n-1
|
||||
if(i.eq.0) go to 30
|
||||
do 20 j=2,n
|
||||
store = z(i)
|
||||
i1 = k1
|
||||
if(j.le.k1) i1 = j-1
|
||||
m = i
|
||||
do 10 l=1,i1
|
||||
m = m+1
|
||||
store = store-c(m)*a(i,l+1)
|
||||
10 continue
|
||||
c(i) = store/a(i,1)
|
||||
i = i-1
|
||||
20 continue
|
||||
30 return
|
||||
end
|
||||
59
cxx/fitpack/fpbacp.f
Normal file
59
cxx/fitpack/fpbacp.f
Normal file
@ -0,0 +1,59 @@
|
||||
recursive subroutine fpbacp(a,b,z,n,k,c,k1,nest)
|
||||
implicit none
|
||||
c subroutine fpbacp calculates the solution of the system of equations
|
||||
c g * c = z with g a n x n upper triangular matrix of the form
|
||||
c ! a ' !
|
||||
c g = ! ' b !
|
||||
c ! 0 ' !
|
||||
c with b a n x k matrix and a a (n-k) x (n-k) upper triangular
|
||||
c matrix of bandwidth k1.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer n,k,k1,nest
|
||||
c ..array arguments..
|
||||
real*8 a(nest,k1),b(nest,k),z(n),c(n)
|
||||
c ..local scalars..
|
||||
integer i,i1,j,l,l0,l1,n2
|
||||
real*8 store
|
||||
c ..
|
||||
n2 = n-k
|
||||
l = n
|
||||
do 30 i=1,k
|
||||
store = z(l)
|
||||
j = k+2-i
|
||||
if(i.eq.1) go to 20
|
||||
l0 = l
|
||||
do 10 l1=j,k
|
||||
l0 = l0+1
|
||||
store = store-c(l0)*b(l,l1)
|
||||
10 continue
|
||||
20 c(l) = store/b(l,j-1)
|
||||
l = l-1
|
||||
if(l.eq.0) go to 80
|
||||
30 continue
|
||||
do 50 i=1,n2
|
||||
store = z(i)
|
||||
l = n2
|
||||
do 40 j=1,k
|
||||
l = l+1
|
||||
store = store-c(l)*b(i,j)
|
||||
40 continue
|
||||
c(i) = store
|
||||
50 continue
|
||||
i = n2
|
||||
c(i) = c(i)/a(i,1)
|
||||
if(i.eq.1) go to 80
|
||||
do 70 j=2,n2
|
||||
i = i-1
|
||||
store = c(i)
|
||||
i1 = k
|
||||
if(j.le.k) i1=j-1
|
||||
l = i
|
||||
do 60 l0=1,i1
|
||||
l = l+1
|
||||
store = store-c(l)*a(i,l0+1)
|
||||
60 continue
|
||||
c(i) = store/a(i,1)
|
||||
70 continue
|
||||
80 return
|
||||
end
|
||||
198
cxx/fitpack/fpbfout.f
Normal file
198
cxx/fitpack/fpbfout.f
Normal file
@ -0,0 +1,198 @@
|
||||
recursive subroutine fpbfou(t,n,par,ress,resc)
|
||||
implicit none
|
||||
c subroutine fpbfou calculates the integrals
|
||||
c /t(n-3)
|
||||
c ress(j) = ! nj,4(x)*sin(par*x) dx and
|
||||
c t(4)/
|
||||
c /t(n-3)
|
||||
c resc(j) = ! nj,4(x)*cos(par*x) dx , j=1,2,...n-4
|
||||
c t(4)/
|
||||
c where nj,4(x) denotes the cubic b-spline defined on the knots
|
||||
c t(j),t(j+1),...,t(j+4).
|
||||
c
|
||||
c calling sequence:
|
||||
c call fpbfou(t,n,par,ress,resc)
|
||||
c
|
||||
c input parameters:
|
||||
c t : real array,length n, containing the knots.
|
||||
c n : integer, containing the number of knots.
|
||||
c par : real, containing the value of the parameter par.
|
||||
c
|
||||
c output parameters:
|
||||
c ress : real array,length n, containing the integrals ress(j).
|
||||
c resc : real array,length n, containing the integrals resc(j).
|
||||
c
|
||||
c restrictions:
|
||||
c n >= 10, t(4) < t(5) < ... < t(n-4) < t(n-3).
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer n
|
||||
real*8 par
|
||||
c ..array arguments..
|
||||
real*8 t(n),ress(n),resc(n)
|
||||
c ..local scalars..
|
||||
integer i,ic,ipj,is,j,jj,jp1,jp4,k,li,lj,ll,nmj,nm3,nm7
|
||||
real*8 ak,beta,con1,con2,c1,c2,delta,eps,fac,f1,f2,f3,one,quart,
|
||||
* sign,six,s1,s2,term
|
||||
c ..local arrays..
|
||||
real*8 co(5),si(5),hs(5),hc(5),rs(3),rc(3)
|
||||
c ..function references..
|
||||
real*8 cos,sin,abs
|
||||
c ..
|
||||
c initialization.
|
||||
one = 0.1e+01
|
||||
six = 0.6e+01
|
||||
eps = 0.1e-07
|
||||
quart = 0.25e0
|
||||
con1 = 0.5e-01
|
||||
con2 = 0.12e+03
|
||||
nm3 = n-3
|
||||
nm7 = n-7
|
||||
if(par.ne.0.) term = six/par
|
||||
beta = par*t(4)
|
||||
co(1) = cos(beta)
|
||||
si(1) = sin(beta)
|
||||
c calculate the integrals ress(j) and resc(j), j=1,2,3 by setting up
|
||||
c a divided difference table.
|
||||
do 30 j=1,3
|
||||
jp1 = j+1
|
||||
jp4 = j+4
|
||||
beta = par*t(jp4)
|
||||
co(jp1) = cos(beta)
|
||||
si(jp1) = sin(beta)
|
||||
call fpcsin(t(4),t(jp4),par,si(1),co(1),si(jp1),co(jp1),
|
||||
* rs(j),rc(j))
|
||||
i = 5-j
|
||||
hs(i) = 0.
|
||||
hc(i) = 0.
|
||||
do 10 jj=1,j
|
||||
ipj = i+jj
|
||||
hs(ipj) = rs(jj)
|
||||
hc(ipj) = rc(jj)
|
||||
10 continue
|
||||
do 20 jj=1,3
|
||||
if(i.lt.jj) i = jj
|
||||
k = 5
|
||||
li = jp4
|
||||
do 20 ll=i,4
|
||||
lj = li-jj
|
||||
fac = t(li)-t(lj)
|
||||
hs(k) = (hs(k)-hs(k-1))/fac
|
||||
hc(k) = (hc(k)-hc(k-1))/fac
|
||||
k = k-1
|
||||
li = li-1
|
||||
20 continue
|
||||
ress(j) = hs(5)-hs(4)
|
||||
resc(j) = hc(5)-hc(4)
|
||||
30 continue
|
||||
if(nm7.lt.4) go to 160
|
||||
c calculate the integrals ress(j) and resc(j),j=4,5,...,n-7.
|
||||
do 150 j=4,nm7
|
||||
jp4 = j+4
|
||||
beta = par*t(jp4)
|
||||
co(5) = cos(beta)
|
||||
si(5) = sin(beta)
|
||||
delta = t(jp4)-t(j)
|
||||
c the way of computing ress(j) and resc(j) depends on the value of
|
||||
c beta = par*(t(j+4)-t(j)).
|
||||
beta = delta*par
|
||||
if(abs(beta).le.one) go to 60
|
||||
c if !beta! > 1 the integrals are calculated by setting up a divided
|
||||
c difference table.
|
||||
do 40 k=1,5
|
||||
hs(k) = si(k)
|
||||
hc(k) = co(k)
|
||||
40 continue
|
||||
do 50 jj=1,3
|
||||
k = 5
|
||||
li = jp4
|
||||
do 50 ll=jj,4
|
||||
lj = li-jj
|
||||
fac = par*(t(li)-t(lj))
|
||||
hs(k) = (hs(k)-hs(k-1))/fac
|
||||
hc(k) = (hc(k)-hc(k-1))/fac
|
||||
k = k-1
|
||||
li = li-1
|
||||
50 continue
|
||||
s2 = (hs(5)-hs(4))*term
|
||||
c2 = (hc(5)-hc(4))*term
|
||||
go to 130
|
||||
c if !beta! <= 1 the integrals are calculated by evaluating a series
|
||||
c expansion.
|
||||
60 f3 = 0.
|
||||
do 70 i=1,4
|
||||
ipj = i+j
|
||||
hs(i) = par*(t(ipj)-t(j))
|
||||
hc(i) = hs(i)
|
||||
f3 = f3+hs(i)
|
||||
70 continue
|
||||
f3 = f3*con1
|
||||
c1 = quart
|
||||
s1 = f3
|
||||
if(abs(f3).le.eps) go to 120
|
||||
sign = one
|
||||
fac = con2
|
||||
k = 5
|
||||
is = 0
|
||||
do 110 ic=1,20
|
||||
k = k+1
|
||||
ak = k
|
||||
fac = fac*ak
|
||||
f1 = 0.
|
||||
f3 = 0.
|
||||
do 80 i=1,4
|
||||
f1 = f1+hc(i)
|
||||
f2 = f1*hs(i)
|
||||
hc(i) = f2
|
||||
f3 = f3+f2
|
||||
80 continue
|
||||
f3 = f3*six/fac
|
||||
if(is.eq.0) go to 90
|
||||
is = 0
|
||||
s1 = s1+f3*sign
|
||||
go to 100
|
||||
90 sign = -sign
|
||||
is = 1
|
||||
c1 = c1+f3*sign
|
||||
100 if(abs(f3).le.eps) go to 120
|
||||
110 continue
|
||||
120 s2 = delta*(co(1)*s1+si(1)*c1)
|
||||
c2 = delta*(co(1)*c1-si(1)*s1)
|
||||
130 ress(j) = s2
|
||||
resc(j) = c2
|
||||
do 140 i=1,4
|
||||
co(i) = co(i+1)
|
||||
si(i) = si(i+1)
|
||||
140 continue
|
||||
150 continue
|
||||
c calculate the integrals ress(j) and resc(j),j=n-6,n-5,n-4 by setting
|
||||
c up a divided difference table.
|
||||
160 do 190 j=1,3
|
||||
nmj = nm3-j
|
||||
i = 5-j
|
||||
call fpcsin(t(nm3),t(nmj),par,si(4),co(4),si(i-1),co(i-1),
|
||||
* rs(j),rc(j))
|
||||
hs(i) = 0.
|
||||
hc(i) = 0.
|
||||
do 170 jj=1,j
|
||||
ipj = i+jj
|
||||
hc(ipj) = rc(jj)
|
||||
hs(ipj) = rs(jj)
|
||||
170 continue
|
||||
do 180 jj=1,3
|
||||
if(i.lt.jj) i = jj
|
||||
k = 5
|
||||
li = nmj
|
||||
do 180 ll=i,4
|
||||
lj = li+jj
|
||||
fac = t(lj)-t(li)
|
||||
hs(k) = (hs(k-1)-hs(k))/fac
|
||||
hc(k) = (hc(k-1)-hc(k))/fac
|
||||
k = k-1
|
||||
li = li+1
|
||||
180 continue
|
||||
ress(nmj) = hs(4)-hs(5)
|
||||
resc(nmj) = hc(4)-hc(5)
|
||||
190 continue
|
||||
return
|
||||
end
|
||||
81
cxx/fitpack/fpbisp.f
Normal file
81
cxx/fitpack/fpbisp.f
Normal file
@ -0,0 +1,81 @@
|
||||
recursive subroutine fpbisp(tx,nx,ty,ny,c,kx,ky,x,mx,y,my,
|
||||
* z,wx,wy,lx,ly)
|
||||
implicit none
|
||||
c ..scalar arguments..
|
||||
integer nx,ny,kx,ky,mx,my
|
||||
c ..array arguments..
|
||||
integer lx(mx),ly(my)
|
||||
real*8 tx(nx),ty(ny),c((nx-kx-1)*(ny-ky-1)),x(mx),y(my),z(mx*my),
|
||||
* wx(mx,kx+1),wy(my,ky+1)
|
||||
c ..local scalars..
|
||||
integer kx1,ky1,l,l1,l2,m,nkx1,nky1, i, i1, j, j1
|
||||
real*8 arg,sp,tb,te
|
||||
c ..local arrays..
|
||||
real*8 h(6)
|
||||
c ..subroutine references..
|
||||
c fpbspl
|
||||
c ..
|
||||
kx1 = kx+1
|
||||
nkx1 = nx-kx1
|
||||
tb = tx(kx1)
|
||||
te = tx(nkx1+1)
|
||||
l = kx1
|
||||
l1 = l+1
|
||||
do 40 i=1,mx
|
||||
arg = x(i)
|
||||
if(arg.lt.tb) arg = tb
|
||||
if(arg.gt.te) arg = te
|
||||
10 if(arg.lt.tx(l1) .or. l.eq.nkx1) go to 20
|
||||
l = l1
|
||||
l1 = l+1
|
||||
go to 10
|
||||
20 call fpbspl(tx,nx,kx,arg,l,h)
|
||||
lx(i) = l-kx1
|
||||
do 30 j=1,kx1
|
||||
wx(i,j) = h(j)
|
||||
30 continue
|
||||
40 continue
|
||||
ky1 = ky+1
|
||||
nky1 = ny-ky1
|
||||
tb = ty(ky1)
|
||||
te = ty(nky1+1)
|
||||
l = ky1
|
||||
l1 = l+1
|
||||
do 80 i=1,my
|
||||
arg = y(i)
|
||||
if(arg.lt.tb) arg = tb
|
||||
if(arg.gt.te) arg = te
|
||||
50 if(arg.lt.ty(l1) .or. l.eq.nky1) go to 60
|
||||
l = l1
|
||||
l1 = l+1
|
||||
go to 50
|
||||
60 call fpbspl(ty,ny,ky,arg,l,h)
|
||||
ly(i) = l-ky1
|
||||
do 70 j=1,ky1
|
||||
wy(i,j) = h(j)
|
||||
70 continue
|
||||
80 continue
|
||||
m = 0
|
||||
do 130 i=1,mx
|
||||
l = lx(i)*nky1
|
||||
do 90 i1=1,kx1
|
||||
h(i1) = wx(i,i1)
|
||||
90 continue
|
||||
do 120 j=1,my
|
||||
l1 = l+ly(j)
|
||||
sp = 0.
|
||||
do 110 i1=1,kx1
|
||||
l2 = l1
|
||||
do 100 j1=1,ky1
|
||||
l2 = l2+1
|
||||
sp = sp+c(l2)*h(i1)*wy(j,j1)
|
||||
100 continue
|
||||
l1 = l1+nky1
|
||||
110 continue
|
||||
m = m+1
|
||||
z(m) = sp
|
||||
120 continue
|
||||
130 continue
|
||||
return
|
||||
end
|
||||
|
||||
42
cxx/fitpack/fpbspl.f
Normal file
42
cxx/fitpack/fpbspl.f
Normal file
@ -0,0 +1,42 @@
|
||||
recursive subroutine fpbspl(t,n,k,x,l,h)
|
||||
c subroutine fpbspl evaluates the (k+1) non-zero b-splines of
|
||||
c degree k at t(l) <= x < t(l+1) using the stable recurrence
|
||||
c relation of de boor and cox.
|
||||
c Travis Oliphant 2007
|
||||
c changed so that weighting of 0 is used when knots with
|
||||
c multiplicity are present.
|
||||
c Also, notice that l+k <= n and 1 <= l+1-k
|
||||
c or else the routine will be accessing memory outside t
|
||||
c Thus it is imperative that that k <= l <= n-k but this
|
||||
c is not checked.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 x
|
||||
integer n,k,l
|
||||
c ..array arguments..
|
||||
real*8 t(n),h(20)
|
||||
c ..local scalars..
|
||||
real*8 f,one
|
||||
integer i,j,li,lj
|
||||
c ..local arrays..
|
||||
real*8 hh(19)
|
||||
c ..
|
||||
one = 0.1d+01
|
||||
h(1) = one
|
||||
do 20 j=1,k
|
||||
do 10 i=1,j
|
||||
hh(i) = h(i)
|
||||
10 continue
|
||||
h(1) = 0.0d0
|
||||
do 20 i=1,j
|
||||
li = l+i
|
||||
lj = li-j
|
||||
if (t(li).ne.t(lj)) goto 15
|
||||
h(i+1) = 0.0d0
|
||||
goto 20
|
||||
15 f = hh(i)/(t(li)-t(lj))
|
||||
h(i) = h(i)+f*(t(li)-x)
|
||||
h(i+1) = f*(x-t(lj))
|
||||
20 continue
|
||||
return
|
||||
end
|
||||
87
cxx/fitpack/fpchec.f
Normal file
87
cxx/fitpack/fpchec.f
Normal file
@ -0,0 +1,87 @@
|
||||
recursive subroutine fpchec(x,m,t,n,k,ier)
|
||||
implicit none
|
||||
c subroutine fpchec verifies the number and the position of the knots
|
||||
c t(j),j=1,2,...,n of a spline of degree k, in relation to the number
|
||||
c and the position of the data points x(i),i=1,2,...,m. if all of the
|
||||
c following conditions are fulfilled, the error parameter ier is set
|
||||
c to zero. if one of the conditions is violated ier is set to ten.
|
||||
c 1) k+1 <= n-k-1 <= m
|
||||
c 2) t(1) <= t(2) <= ... <= t(k+1)
|
||||
c t(n-k) <= t(n-k+1) <= ... <= t(n)
|
||||
c 3) t(k+1) < t(k+2) < ... < t(n-k)
|
||||
c 4) t(k+1) <= x(i) <= t(n-k)
|
||||
c 5) the conditions specified by schoenberg and whitney must hold
|
||||
c for at least one subset of data points, i.e. there must be a
|
||||
c subset of data points y(j) such that
|
||||
c t(j) < y(j) < t(j+k+1), j=1,2,...,n-k-1
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer m,n,k,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),t(n)
|
||||
c ..local scalars..
|
||||
integer i,j,k1,k2,l,nk1,nk2,nk3
|
||||
real*8 tj,tl
|
||||
c ..
|
||||
k1 = k+1
|
||||
k2 = k1+1
|
||||
nk1 = n-k1
|
||||
nk2 = nk1+1
|
||||
ier = 10
|
||||
c check condition no 1
|
||||
if (nk1.lt.k1 .or. nk1.gt.m) then
|
||||
ier = 10
|
||||
go to 80
|
||||
endif
|
||||
c check condition no 2
|
||||
j = n
|
||||
do 20 i=1,k
|
||||
if (t(i) .gt. t(i+1)) then
|
||||
ier = 20
|
||||
go to 80
|
||||
endif
|
||||
if (t(j) .lt. t(j-1)) then
|
||||
ier = 20
|
||||
go to 80
|
||||
endif
|
||||
j = j-1
|
||||
20 continue
|
||||
c check condition no 3
|
||||
do 30 i=k2,nk2
|
||||
if (t(i) .le. t(i-1)) then
|
||||
ier = 30
|
||||
go to 80
|
||||
endif
|
||||
30 continue
|
||||
c check condition no 4
|
||||
if (x(1).lt.t(k1) .or. x(m).gt.t(nk2)) then
|
||||
ier = 40
|
||||
go to 80
|
||||
endif
|
||||
c check condition no 5
|
||||
if (x(1).ge.t(k2) .or. x(m).le.t(nk1)) then
|
||||
ier = 50
|
||||
go to 80
|
||||
endif
|
||||
i = 1
|
||||
l = k2
|
||||
nk3 = nk1-1
|
||||
if (nk3 .lt. 2) go to 70
|
||||
do 60 j=2,nk3
|
||||
tj = t(j)
|
||||
l = l+1
|
||||
tl = t(l)
|
||||
40 i = i+1
|
||||
if (i .ge. m) then
|
||||
ier = 50
|
||||
go to 80
|
||||
endif
|
||||
if (x(i) .le. tj) go to 40
|
||||
if (x(i) .ge. tl) then
|
||||
ier = 50
|
||||
go to 80
|
||||
endif
|
||||
60 continue
|
||||
70 ier = 0
|
||||
80 return
|
||||
end
|
||||
70
cxx/fitpack/fpched.f
Normal file
70
cxx/fitpack/fpched.f
Normal file
@ -0,0 +1,70 @@
|
||||
recursive subroutine fpched(x,m,t,n,k,ib,ie,ier)
|
||||
implicit none
|
||||
c subroutine fpched verifies the number and the position of the knots
|
||||
c t(j),j=1,2,...,n of a spline of degree k,with ib derative constraints
|
||||
c at x(1) and ie constraints at x(m), in relation to the number and
|
||||
c the position of the data points x(i),i=1,2,...,m. if all of the
|
||||
c following conditions are fulfilled, the error parameter ier is set
|
||||
c to zero. if one of the conditions is violated ier is set to ten.
|
||||
c 1) k+1 <= n-k-1 <= m + max(0,ib-1) + max(0,ie-1)
|
||||
c 2) t(1) <= t(2) <= ... <= t(k+1)
|
||||
c t(n-k) <= t(n-k+1) <= ... <= t(n)
|
||||
c 3) t(k+1) < t(k+2) < ... < t(n-k)
|
||||
c 4) t(k+1) <= x(i) <= t(n-k)
|
||||
c 5) the conditions specified by schoenberg and whitney must hold
|
||||
c for at least one subset of data points, i.e. there must be a
|
||||
c subset of data points y(j) such that
|
||||
c t(j) < y(j) < t(j+k+1), j=1+ib1,2+ib1,...,n-k-1-ie1
|
||||
c with ib1 = max(0,ib-1), ie1 = max(0,ie-1)
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer m,n,k,ib,ie,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),t(n)
|
||||
c ..local scalars..
|
||||
integer i,ib1,ie1,j,jj,k1,k2,l,nk1,nk2,nk3
|
||||
real*8 tj,tl
|
||||
c ..
|
||||
k1 = k+1
|
||||
k2 = k1+1
|
||||
nk1 = n-k1
|
||||
nk2 = nk1+1
|
||||
ib1 = ib-1
|
||||
if(ib1.lt.0) ib1 = 0
|
||||
ie1 = ie-1
|
||||
if(ie1.lt.0) ie1 = 0
|
||||
ier = 10
|
||||
c check condition no 1
|
||||
if(nk1.lt.k1 .or. nk1.gt.(m+ib1+ie1)) go to 80
|
||||
c check condition no 2
|
||||
j = n
|
||||
do 20 i=1,k
|
||||
if(t(i).gt.t(i+1)) go to 80
|
||||
if(t(j).lt.t(j-1)) go to 80
|
||||
j = j-1
|
||||
20 continue
|
||||
c check condition no 3
|
||||
do 30 i=k2,nk2
|
||||
if(t(i).le.t(i-1)) go to 80
|
||||
30 continue
|
||||
c check condition no 4
|
||||
if(x(1).lt.t(k1) .or. x(m).gt.t(nk2)) go to 80
|
||||
c check condition no 5
|
||||
if(x(1).ge.t(k2) .or. x(m).le.t(nk1)) go to 80
|
||||
i = 1
|
||||
jj = 2+ib1
|
||||
l = jj+k
|
||||
nk3 = nk1-1-ie1
|
||||
if(nk3.lt.jj) go to 70
|
||||
do 60 j=jj,nk3
|
||||
tj = t(j)
|
||||
l = l+1
|
||||
tl = t(l)
|
||||
40 i = i+1
|
||||
if(i.ge.m) go to 80
|
||||
if(x(i).le.tj) go to 40
|
||||
if(x(i).ge.tl) go to 80
|
||||
60 continue
|
||||
70 ier = 0
|
||||
80 return
|
||||
end
|
||||
82
cxx/fitpack/fpchep.f
Normal file
82
cxx/fitpack/fpchep.f
Normal file
@ -0,0 +1,82 @@
|
||||
recursive subroutine fpchep(x,m,t,n,k,ier)
|
||||
implicit none
|
||||
c subroutine fpchep verifies the number and the position of the knots
|
||||
c t(j),j=1,2,...,n of a periodic spline of degree k, in relation to
|
||||
c the number and the position of the data points x(i),i=1,2,...,m.
|
||||
c if all of the following conditions are fulfilled, ier is set
|
||||
c to zero. if one of the conditions is violated ier is set to ten.
|
||||
c 1) k+1 <= n-k-1 <= m+k-1
|
||||
c 2) t(1) <= t(2) <= ... <= t(k+1)
|
||||
c t(n-k) <= t(n-k+1) <= ... <= t(n)
|
||||
c 3) t(k+1) < t(k+2) < ... < t(n-k)
|
||||
c 4) t(k+1) <= x(i) <= t(n-k)
|
||||
c 5) the conditions specified by schoenberg and whitney must hold
|
||||
c for at least one subset of data points, i.e. there must be a
|
||||
c subset of data points y(j) such that
|
||||
c t(j) < y(j) < t(j+k+1), j=k+1,...,n-k-1
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer m,n,k,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),t(n)
|
||||
c ..local scalars..
|
||||
integer i,i1,i2,j,j1,k1,k2,l,l1,l2,mm,m1,nk1,nk2
|
||||
real*8 per,tj,tl,xi
|
||||
c ..
|
||||
k1 = k+1
|
||||
k2 = k1+1
|
||||
nk1 = n-k1
|
||||
nk2 = nk1+1
|
||||
m1 = m-1
|
||||
ier = 10
|
||||
c check condition no 1
|
||||
if(nk1.lt.k1 .or. n.gt.m+2*k) go to 130
|
||||
c check condition no 2
|
||||
j = n
|
||||
do 20 i=1,k
|
||||
if(t(i).gt.t(i+1)) go to 130
|
||||
if(t(j).lt.t(j-1)) go to 130
|
||||
j = j-1
|
||||
20 continue
|
||||
c check condition no 3
|
||||
do 30 i=k2,nk2
|
||||
if(t(i).le.t(i-1)) go to 130
|
||||
30 continue
|
||||
c check condition no 4
|
||||
if(x(1).lt.t(k1) .or. x(m).gt.t(nk2)) go to 130
|
||||
c check condition no 5
|
||||
l1 = k1
|
||||
l2 = 1
|
||||
do 50 l=1,m
|
||||
xi = x(l)
|
||||
40 if(xi.lt.t(l1+1) .or. l.eq.nk1) go to 50
|
||||
l1 = l1+1
|
||||
l2 = l2+1
|
||||
if(l2.gt.k1) go to 60
|
||||
go to 40
|
||||
50 continue
|
||||
l = m
|
||||
60 per = t(nk2)-t(k1)
|
||||
do 120 i1=2,l
|
||||
i = i1-1
|
||||
mm = i+m1
|
||||
do 110 j=k1,nk1
|
||||
tj = t(j)
|
||||
j1 = j+k1
|
||||
tl = t(j1)
|
||||
70 i = i+1
|
||||
if(i.gt.mm) go to 120
|
||||
i2 = i-m1
|
||||
if (i2.le.0) go to 80
|
||||
go to 90
|
||||
80 xi = x(i)
|
||||
go to 100
|
||||
90 xi = x(i2)+per
|
||||
100 if(xi.le.tj) go to 70
|
||||
if(xi.ge.tl) go to 120
|
||||
110 continue
|
||||
ier = 0
|
||||
go to 130
|
||||
120 continue
|
||||
130 return
|
||||
end
|
||||
715
cxx/fitpack/fpclos.f
Normal file
715
cxx/fitpack/fpclos.f
Normal file
@ -0,0 +1,715 @@
|
||||
recursive subroutine fpclos(iopt,idim,m,u,mx,x,w,k,s,nest,tol,
|
||||
* maxit,k1,k2,n,t,nc,c,fp,fpint,z,a1,a2,b,g1,g2,q,nrdata,ier)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 s,tol,fp
|
||||
integer iopt,idim,m,mx,k,nest,maxit,k1,k2,n,nc,ier
|
||||
c ..array arguments..
|
||||
real*8 u(m),x(mx),w(m),t(nest),c(nc),fpint(nest),z(nc),a1(nest,k1)
|
||||
*,
|
||||
* a2(nest,k),b(nest,k2),g1(nest,k2),g2(nest,k1),q(m,k1)
|
||||
integer nrdata(nest)
|
||||
c ..local scalars..
|
||||
real*8 acc,cos,d1,fac,fpart,fpms,fpold,fp0,f1,f2,f3,p,per,pinv,piv
|
||||
*,
|
||||
* p1,p2,p3,sin,store,term,ui,wi,rn,one,con1,con4,con9,half
|
||||
integer i,ich1,ich3,ij,ik,it,iter,i1,i2,i3,j,jj,jk,jper,j1,j2,kk,
|
||||
* kk1,k3,l,l0,l1,l5,mm,m1,new,nk1,nk2,nmax,nmin,nplus,npl1,
|
||||
* nrint,n10,n11,n7,n8
|
||||
c ..local arrays..
|
||||
real*8 h(6),h1(7),h2(6),xi(10)
|
||||
c ..function references..
|
||||
real*8 abs,fprati
|
||||
integer max0,min0
|
||||
c ..subroutine references..
|
||||
c fpbacp,fpbspl,fpgivs,fpdisc,fpknot,fprota
|
||||
c ..
|
||||
c set constants
|
||||
one = 0.1e+01
|
||||
con1 = 0.1e0
|
||||
con9 = 0.9e0
|
||||
con4 = 0.4e-01
|
||||
half = 0.5e0
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 1: determination of the number of knots and their position c
|
||||
c ************************************************************** c
|
||||
c given a set of knots we compute the least-squares closed curve c
|
||||
c sinf(u). if the sum f(p=inf) <= s we accept the choice of knots. c
|
||||
c if iopt=-1 sinf(u) is the requested curve c
|
||||
c if iopt=0 or iopt=1 we check whether we can accept the knots: c
|
||||
c if fp <=s we will continue with the current set of knots. c
|
||||
c if fp > s we will increase the number of knots and compute the c
|
||||
c corresponding least-squares curve until finally fp<=s. c
|
||||
c the initial choice of knots depends on the value of s and iopt. c
|
||||
c if s=0 we have spline interpolation; in that case the number of c
|
||||
c knots equals nmax = m+2*k. c
|
||||
c if s > 0 and c
|
||||
c iopt=0 we first compute the least-squares polynomial curve of c
|
||||
c degree k; n = nmin = 2*k+2. since s(u) must be periodic we c
|
||||
c find that s(u) reduces to a fixed point. c
|
||||
c iopt=1 we start with the set of knots found at the last c
|
||||
c call of the routine, except for the case that s > fp0; then c
|
||||
c we compute directly the least-squares polynomial curve. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
m1 = m-1
|
||||
kk = k
|
||||
kk1 = k1
|
||||
k3 = 3*k+1
|
||||
nmin = 2*k1
|
||||
c determine the length of the period of the splines.
|
||||
per = u(m)-u(1)
|
||||
if(iopt.lt.0) go to 50
|
||||
c calculation of acc, the absolute tolerance for the root of f(p)=s.
|
||||
acc = tol*s
|
||||
c determine nmax, the number of knots for periodic spline interpolation
|
||||
nmax = m+2*k
|
||||
if(s.gt.0. .or. nmax.eq.nmin) go to 30
|
||||
c if s=0, s(u) is an interpolating curve.
|
||||
n = nmax
|
||||
c test whether the required storage space exceeds the available one.
|
||||
if(n.gt.nest) go to 620
|
||||
c find the position of the interior knots in case of interpolation.
|
||||
5 if((k/2)*2 .eq.k) go to 20
|
||||
do 10 i=2,m1
|
||||
j = i+k
|
||||
t(j) = u(i)
|
||||
10 continue
|
||||
if(s.gt.0.) go to 50
|
||||
kk = k-1
|
||||
kk1 = k
|
||||
if(kk.gt.0) go to 50
|
||||
t(1) = t(m)-per
|
||||
t(2) = u(1)
|
||||
t(m+1) = u(m)
|
||||
t(m+2) = t(3)+per
|
||||
jj = 0
|
||||
do 15 i=1,m1
|
||||
j = i
|
||||
do 12 j1=1,idim
|
||||
jj = jj+1
|
||||
c(j) = x(jj)
|
||||
j = j+n
|
||||
12 continue
|
||||
15 continue
|
||||
jj = 1
|
||||
j = m
|
||||
do 17 j1=1,idim
|
||||
c(j) = c(jj)
|
||||
j = j+n
|
||||
jj = jj+n
|
||||
17 continue
|
||||
fp = 0.
|
||||
fpint(n) = fp0
|
||||
fpint(n-1) = 0.
|
||||
nrdata(n) = 0
|
||||
go to 630
|
||||
20 do 25 i=2,m1
|
||||
j = i+k
|
||||
t(j) = (u(i)+u(i-1))*half
|
||||
25 continue
|
||||
go to 50
|
||||
c if s > 0 our initial choice depends on the value of iopt.
|
||||
c if iopt=0 or iopt=1 and s>=fp0, we start computing the least-squares
|
||||
c polynomial curve. (i.e. a constant point).
|
||||
c if iopt=1 and fp0>s we start computing the least-squares closed
|
||||
c curve according the set of knots found at the last call of the
|
||||
c routine.
|
||||
30 if(iopt.eq.0) go to 35
|
||||
if(n.eq.nmin) go to 35
|
||||
fp0 = fpint(n)
|
||||
fpold = fpint(n-1)
|
||||
nplus = nrdata(n)
|
||||
if(fp0.gt.s) go to 50
|
||||
c the case that s(u) is a fixed point is treated separetely.
|
||||
c fp0 denotes the corresponding sum of squared residuals.
|
||||
35 fp0 = 0.
|
||||
d1 = 0.
|
||||
do 37 j=1,idim
|
||||
z(j) = 0.
|
||||
37 continue
|
||||
jj = 0
|
||||
do 45 it=1,m1
|
||||
wi = w(it)
|
||||
call fpgivs(wi,d1,cos,sin)
|
||||
do 40 j=1,idim
|
||||
jj = jj+1
|
||||
fac = wi*x(jj)
|
||||
call fprota(cos,sin,fac,z(j))
|
||||
fp0 = fp0+fac**2
|
||||
40 continue
|
||||
45 continue
|
||||
do 47 j=1,idim
|
||||
z(j) = z(j)/d1
|
||||
47 continue
|
||||
c test whether that fixed point is a solution of our problem.
|
||||
fpms = fp0-s
|
||||
if(fpms.lt.acc .or. nmax.eq.nmin) go to 640
|
||||
fpold = fp0
|
||||
c test whether the required storage space exceeds the available one.
|
||||
if(n.ge.nest) go to 620
|
||||
c start computing the least-squares closed curve with one
|
||||
c interior knot.
|
||||
nplus = 1
|
||||
n = nmin+1
|
||||
mm = (m+1)/2
|
||||
t(k2) = u(mm)
|
||||
nrdata(1) = mm-2
|
||||
nrdata(2) = m1-mm
|
||||
c main loop for the different sets of knots. m is a save upper
|
||||
c bound for the number of trials.
|
||||
50 do 340 iter=1,m
|
||||
c find nrint, the number of knot intervals.
|
||||
nrint = n-nmin+1
|
||||
c find the position of the additional knots which are needed for
|
||||
c the b-spline representation of s(u). if we take
|
||||
c t(k+1) = u(1), t(n-k) = u(m)
|
||||
c t(k+1-j) = t(n-k-j) - per, j=1,2,...k
|
||||
c t(n-k+j) = t(k+1+j) + per, j=1,2,...k
|
||||
c then s(u) will be a smooth closed curve if the b-spline
|
||||
c coefficients satisfy the following conditions
|
||||
c c((i-1)*n+n7+j) = c((i-1)*n+j), j=1,...k,i=1,2,...,idim (**)
|
||||
c with n7=n-2*k-1.
|
||||
t(k1) = u(1)
|
||||
nk1 = n-k1
|
||||
nk2 = nk1+1
|
||||
t(nk2) = u(m)
|
||||
do 60 j=1,k
|
||||
i1 = nk2+j
|
||||
i2 = nk2-j
|
||||
j1 = k1+j
|
||||
j2 = k1-j
|
||||
t(i1) = t(j1)+per
|
||||
t(j2) = t(i2)-per
|
||||
60 continue
|
||||
c compute the b-spline coefficients of the least-squares closed curve
|
||||
c sinf(u). the observation matrix a is built up row by row while
|
||||
c taking into account condition (**) and is reduced to triangular
|
||||
c form by givens transformations .
|
||||
c at the same time fp=f(p=inf) is computed.
|
||||
c the n7 x n7 triangularised upper matrix a has the form
|
||||
c ! a1 ' !
|
||||
c a = ! ' a2 !
|
||||
c ! 0 ' !
|
||||
c with a2 a n7 x k matrix and a1 a n10 x n10 upper triangular
|
||||
c matrix of bandwidth k+1 ( n10 = n7-k).
|
||||
c initialization.
|
||||
do 65 i=1,nc
|
||||
z(i) = 0.
|
||||
65 continue
|
||||
do 70 i=1,nk1
|
||||
do 70 j=1,kk1
|
||||
a1(i,j) = 0.
|
||||
70 continue
|
||||
n7 = nk1-k
|
||||
n10 = n7-kk
|
||||
jper = 0
|
||||
fp = 0.
|
||||
l = k1
|
||||
jj = 0
|
||||
do 290 it=1,m1
|
||||
c fetch the current data point u(it),x(it)
|
||||
ui = u(it)
|
||||
wi = w(it)
|
||||
do 75 j=1,idim
|
||||
jj = jj+1
|
||||
xi(j) = x(jj)*wi
|
||||
75 continue
|
||||
c search for knot interval t(l) <= ui < t(l+1).
|
||||
80 if(ui.lt.t(l+1)) go to 85
|
||||
l = l+1
|
||||
go to 80
|
||||
c evaluate the (k+1) non-zero b-splines at ui and store them in q.
|
||||
85 call fpbspl(t,n,k,ui,l,h)
|
||||
do 90 i=1,k1
|
||||
q(it,i) = h(i)
|
||||
h(i) = h(i)*wi
|
||||
90 continue
|
||||
l5 = l-k1
|
||||
c test whether the b-splines nj,k+1(u),j=1+n7,...nk1 are all zero at ui
|
||||
if(l5.lt.n10) go to 285
|
||||
if(jper.ne.0) go to 160
|
||||
c initialize the matrix a2.
|
||||
do 95 i=1,n7
|
||||
do 95 j=1,kk
|
||||
a2(i,j) = 0.
|
||||
95 continue
|
||||
jk = n10+1
|
||||
do 110 i=1,kk
|
||||
ik = jk
|
||||
do 100 j=1,kk1
|
||||
if(ik.le.0) go to 105
|
||||
a2(ik,i) = a1(ik,j)
|
||||
ik = ik-1
|
||||
100 continue
|
||||
105 jk = jk+1
|
||||
110 continue
|
||||
jper = 1
|
||||
c if one of the b-splines nj,k+1(u),j=n7+1,...nk1 is not zero at ui
|
||||
c we take account of condition (**) for setting up the new row
|
||||
c of the observation matrix a. this row is stored in the arrays h1
|
||||
c (the part with respect to a1) and h2 (the part with
|
||||
c respect to a2).
|
||||
160 do 170 i=1,kk
|
||||
h1(i) = 0.
|
||||
h2(i) = 0.
|
||||
170 continue
|
||||
h1(kk1) = 0.
|
||||
j = l5-n10
|
||||
do 210 i=1,kk1
|
||||
j = j+1
|
||||
l0 = j
|
||||
180 l1 = l0-kk
|
||||
if(l1.le.0) go to 200
|
||||
if(l1.le.n10) go to 190
|
||||
l0 = l1-n10
|
||||
go to 180
|
||||
190 h1(l1) = h(i)
|
||||
go to 210
|
||||
200 h2(l0) = h2(l0)+h(i)
|
||||
210 continue
|
||||
c rotate the new row of the observation matrix into triangle
|
||||
c by givens transformations.
|
||||
if(n10.le.0) go to 250
|
||||
c rotation with the rows 1,2,...n10 of matrix a.
|
||||
do 240 j=1,n10
|
||||
piv = h1(1)
|
||||
if(piv.ne.0.) go to 214
|
||||
do 212 i=1,kk
|
||||
h1(i) = h1(i+1)
|
||||
212 continue
|
||||
h1(kk1) = 0.
|
||||
go to 240
|
||||
c calculate the parameters of the givens transformation.
|
||||
214 call fpgivs(piv,a1(j,1),cos,sin)
|
||||
c transformation to the right hand side.
|
||||
j1 = j
|
||||
do 217 j2=1,idim
|
||||
call fprota(cos,sin,xi(j2),z(j1))
|
||||
j1 = j1+n
|
||||
217 continue
|
||||
c transformations to the left hand side with respect to a2.
|
||||
do 220 i=1,kk
|
||||
call fprota(cos,sin,h2(i),a2(j,i))
|
||||
220 continue
|
||||
if(j.eq.n10) go to 250
|
||||
i2 = min0(n10-j,kk)
|
||||
c transformations to the left hand side with respect to a1.
|
||||
do 230 i=1,i2
|
||||
i1 = i+1
|
||||
call fprota(cos,sin,h1(i1),a1(j,i1))
|
||||
h1(i) = h1(i1)
|
||||
230 continue
|
||||
h1(i1) = 0.
|
||||
240 continue
|
||||
c rotation with the rows n10+1,...n7 of matrix a.
|
||||
250 do 270 j=1,kk
|
||||
ij = n10+j
|
||||
if(ij.le.0) go to 270
|
||||
piv = h2(j)
|
||||
if(piv.eq.0.) go to 270
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a2(ij,j),cos,sin)
|
||||
c transformations to right hand side.
|
||||
j1 = ij
|
||||
do 255 j2=1,idim
|
||||
call fprota(cos,sin,xi(j2),z(j1))
|
||||
j1 = j1+n
|
||||
255 continue
|
||||
if(j.eq.kk) go to 280
|
||||
j1 = j+1
|
||||
c transformations to left hand side.
|
||||
do 260 i=j1,kk
|
||||
call fprota(cos,sin,h2(i),a2(ij,i))
|
||||
260 continue
|
||||
270 continue
|
||||
c add contribution of this row to the sum of squares of residual
|
||||
c right hand sides.
|
||||
280 do 282 j2=1,idim
|
||||
fp = fp+xi(j2)**2
|
||||
282 continue
|
||||
go to 290
|
||||
c rotation of the new row of the observation matrix into
|
||||
c triangle in case the b-splines nj,k+1(u),j=n7+1,...n-k-1 are all zero
|
||||
c at ui.
|
||||
285 j = l5
|
||||
do 140 i=1,kk1
|
||||
j = j+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 140
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a1(j,1),cos,sin)
|
||||
c transformations to right hand side.
|
||||
j1 = j
|
||||
do 125 j2=1,idim
|
||||
call fprota(cos,sin,xi(j2),z(j1))
|
||||
j1 = j1+n
|
||||
125 continue
|
||||
if(i.eq.kk1) go to 150
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
c transformations to left hand side.
|
||||
do 130 i1=i3,kk1
|
||||
i2 = i2+1
|
||||
call fprota(cos,sin,h(i1),a1(j,i2))
|
||||
130 continue
|
||||
140 continue
|
||||
c add contribution of this row to the sum of squares of residual
|
||||
c right hand sides.
|
||||
150 do 155 j2=1,idim
|
||||
fp = fp+xi(j2)**2
|
||||
155 continue
|
||||
290 continue
|
||||
fpint(n) = fp0
|
||||
fpint(n-1) = fpold
|
||||
nrdata(n) = nplus
|
||||
c backward substitution to obtain the b-spline coefficients .
|
||||
j1 = 1
|
||||
do 292 j2=1,idim
|
||||
call fpbacp(a1,a2,z(j1),n7,kk,c(j1),kk1,nest)
|
||||
j1 = j1+n
|
||||
292 continue
|
||||
c calculate from condition (**) the remaining coefficients.
|
||||
do 297 i=1,k
|
||||
j1 = i
|
||||
do 295 j=1,idim
|
||||
j2 = j1+n7
|
||||
c(j2) = c(j1)
|
||||
j1 = j1+n
|
||||
295 continue
|
||||
297 continue
|
||||
if(iopt.lt.0) go to 660
|
||||
c test whether the approximation sinf(u) is an acceptable solution.
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 660
|
||||
c if f(p=inf) < s accept the choice of knots.
|
||||
if(fpms.lt.0.) go to 350
|
||||
c if n=nmax, sinf(u) is an interpolating curve.
|
||||
if(n.eq.nmax) go to 630
|
||||
c increase the number of knots.
|
||||
c if n=nest we cannot increase the number of knots because of the
|
||||
c storage capacity limitation.
|
||||
if(n.eq.nest) go to 620
|
||||
c determine the number of knots nplus we are going to add.
|
||||
npl1 = nplus*2
|
||||
rn = nplus
|
||||
if(fpold-fp.gt.acc) npl1 = rn*fpms/(fpold-fp)
|
||||
nplus = min0(nplus*2,max0(npl1,nplus/2,1))
|
||||
fpold = fp
|
||||
c compute the sum of squared residuals for each knot interval
|
||||
c t(j+k) <= ui <= t(j+k+1) and store it in fpint(j),j=1,2,...nrint.
|
||||
fpart = 0.
|
||||
i = 1
|
||||
l = k1
|
||||
jj = 0
|
||||
do 320 it=1,m1
|
||||
if(u(it).lt.t(l)) go to 300
|
||||
new = 1
|
||||
l = l+1
|
||||
300 term = 0.
|
||||
l0 = l-k2
|
||||
do 310 j2=1,idim
|
||||
fac = 0.
|
||||
j1 = l0
|
||||
do 305 j=1,k1
|
||||
j1 = j1+1
|
||||
fac = fac+c(j1)*q(it,j)
|
||||
305 continue
|
||||
jj = jj+1
|
||||
term = term+(w(it)*(fac-x(jj)))**2
|
||||
l0 = l0+n
|
||||
310 continue
|
||||
fpart = fpart+term
|
||||
if(new.eq.0) go to 320
|
||||
if(l.gt.k2) go to 315
|
||||
fpint(nrint) = term
|
||||
new = 0
|
||||
go to 320
|
||||
315 store = term*half
|
||||
fpint(i) = fpart-store
|
||||
i = i+1
|
||||
fpart = store
|
||||
new = 0
|
||||
320 continue
|
||||
fpint(nrint) = fpint(nrint)+fpart
|
||||
do 330 l=1,nplus
|
||||
c add a new knot
|
||||
call fpknot(u,m,t,n,fpint,nrdata,nrint,nest,1)
|
||||
c if n=nmax we locate the knots as for interpolation
|
||||
if(n.eq.nmax) go to 5
|
||||
c test whether we cannot further increase the number of knots.
|
||||
if(n.eq.nest) go to 340
|
||||
330 continue
|
||||
c restart the computations with the new set of knots.
|
||||
340 continue
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 2: determination of the smoothing closed curve sp(u). c
|
||||
c ********************************************************** c
|
||||
c we have determined the number of knots and their position. c
|
||||
c we now compute the b-spline coefficients of the smoothing curve c
|
||||
c sp(u). the observation matrix a is extended by the rows of matrix c
|
||||
c b expressing that the kth derivative discontinuities of sp(u) at c
|
||||
c the interior knots t(k+2),...t(n-k-1) must be zero. the corres- c
|
||||
c ponding weights of these additional rows are set to 1/p. c
|
||||
c iteratively we then have to determine the value of p such that f(p),c
|
||||
c the sum of squared residuals be = s. we already know that the least-c
|
||||
c squares polynomial curve corresponds to p=0, and that the least- c
|
||||
c squares periodic spline curve corresponds to p=infinity. the c
|
||||
c iteration process which is proposed here, makes use of rational c
|
||||
c interpolation. since f(p) is a convex and strictly decreasing c
|
||||
c function of p, it can be approximated by a rational function c
|
||||
c r(p) = (u*p+v)/(p+w). three values of p(p1,p2,p3) with correspond- c
|
||||
c ing values of f(p) (f1=f(p1)-s,f2=f(p2)-s,f3=f(p3)-s) are used c
|
||||
c to calculate the new value of p such that r(p)=s. convergence is c
|
||||
c guaranteed by taking f1>0 and f3<0. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c evaluate the discontinuity jump of the kth derivative of the
|
||||
c b-splines at the knots t(l),l=k+2,...n-k-1 and store in b.
|
||||
350 call fpdisc(t,n,k2,b,nest)
|
||||
c initial value for p.
|
||||
p1 = 0.
|
||||
f1 = fp0-s
|
||||
p3 = -one
|
||||
f3 = fpms
|
||||
n11 = n10-1
|
||||
n8 = n7-1
|
||||
p = 0.
|
||||
l = n7
|
||||
do 352 i=1,k
|
||||
j = k+1-i
|
||||
p = p+a2(l,j)
|
||||
l = l-1
|
||||
if(l.eq.0) go to 356
|
||||
352 continue
|
||||
do 354 i=1,n10
|
||||
p = p+a1(i,1)
|
||||
354 continue
|
||||
356 rn = n7
|
||||
p = rn/p
|
||||
ich1 = 0
|
||||
ich3 = 0
|
||||
c iteration process to find the root of f(p) = s.
|
||||
do 595 iter=1,maxit
|
||||
c form the matrix g as the matrix a extended by the rows of matrix b.
|
||||
c the rows of matrix b with weight 1/p are rotated into
|
||||
c the triangularised observation matrix a.
|
||||
c after triangularisation our n7 x n7 matrix g takes the form
|
||||
c ! g1 ' !
|
||||
c g = ! ' g2 !
|
||||
c ! 0 ' !
|
||||
c with g2 a n7 x (k+1) matrix and g1 a n11 x n11 upper triangular
|
||||
c matrix of bandwidth k+2. ( n11 = n7-k-1)
|
||||
pinv = one/p
|
||||
c store matrix a into g
|
||||
do 358 i=1,nc
|
||||
c(i) = z(i)
|
||||
358 continue
|
||||
do 360 i=1,n7
|
||||
g1(i,k1) = a1(i,k1)
|
||||
g1(i,k2) = 0.
|
||||
g2(i,1) = 0.
|
||||
do 360 j=1,k
|
||||
g1(i,j) = a1(i,j)
|
||||
g2(i,j+1) = a2(i,j)
|
||||
360 continue
|
||||
l = n10
|
||||
do 370 j=1,k1
|
||||
if(l.le.0) go to 375
|
||||
g2(l,1) = a1(l,j)
|
||||
l = l-1
|
||||
370 continue
|
||||
375 do 540 it=1,n8
|
||||
c fetch a new row of matrix b and store it in the arrays h1 (the part
|
||||
c with respect to g1) and h2 (the part with respect to g2).
|
||||
do 380 j=1,idim
|
||||
xi(j) = 0.
|
||||
380 continue
|
||||
do 385 i=1,k1
|
||||
h1(i) = 0.
|
||||
h2(i) = 0.
|
||||
385 continue
|
||||
h1(k2) = 0.
|
||||
if(it.gt.n11) go to 420
|
||||
l = it
|
||||
l0 = it
|
||||
do 390 j=1,k2
|
||||
if(l0.eq.n10) go to 400
|
||||
h1(j) = b(it,j)*pinv
|
||||
l0 = l0+1
|
||||
390 continue
|
||||
go to 470
|
||||
400 l0 = 1
|
||||
do 410 l1=j,k2
|
||||
h2(l0) = b(it,l1)*pinv
|
||||
l0 = l0+1
|
||||
410 continue
|
||||
go to 470
|
||||
420 l = 1
|
||||
i = it-n10
|
||||
do 460 j=1,k2
|
||||
i = i+1
|
||||
l0 = i
|
||||
430 l1 = l0-k1
|
||||
if(l1.le.0) go to 450
|
||||
if(l1.le.n11) go to 440
|
||||
l0 = l1-n11
|
||||
go to 430
|
||||
440 h1(l1) = b(it,j)*pinv
|
||||
go to 460
|
||||
450 h2(l0) = h2(l0)+b(it,j)*pinv
|
||||
460 continue
|
||||
if(n11.le.0) go to 510
|
||||
c rotate this row into triangle by givens transformations
|
||||
c rotation with the rows l,l+1,...n11.
|
||||
470 do 500 j=l,n11
|
||||
piv = h1(1)
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,g1(j,1),cos,sin)
|
||||
c transformation to right hand side.
|
||||
j1 = j
|
||||
do 475 j2=1,idim
|
||||
call fprota(cos,sin,xi(j2),c(j1))
|
||||
j1 = j1+n
|
||||
475 continue
|
||||
c transformation to the left hand side with respect to g2.
|
||||
do 480 i=1,k1
|
||||
call fprota(cos,sin,h2(i),g2(j,i))
|
||||
480 continue
|
||||
if(j.eq.n11) go to 510
|
||||
i2 = min0(n11-j,k1)
|
||||
c transformation to the left hand side with respect to g1.
|
||||
do 490 i=1,i2
|
||||
i1 = i+1
|
||||
call fprota(cos,sin,h1(i1),g1(j,i1))
|
||||
h1(i) = h1(i1)
|
||||
490 continue
|
||||
h1(i1) = 0.
|
||||
500 continue
|
||||
c rotation with the rows n11+1,...n7
|
||||
510 do 530 j=1,k1
|
||||
ij = n11+j
|
||||
if(ij.le.0) go to 530
|
||||
piv = h2(j)
|
||||
c calculate the parameters of the givens transformation
|
||||
call fpgivs(piv,g2(ij,j),cos,sin)
|
||||
c transformation to the right hand side.
|
||||
j1 = ij
|
||||
do 515 j2=1,idim
|
||||
call fprota(cos,sin,xi(j2),c(j1))
|
||||
j1 = j1+n
|
||||
515 continue
|
||||
if(j.eq.k1) go to 540
|
||||
j1 = j+1
|
||||
c transformation to the left hand side.
|
||||
do 520 i=j1,k1
|
||||
call fprota(cos,sin,h2(i),g2(ij,i))
|
||||
520 continue
|
||||
530 continue
|
||||
540 continue
|
||||
c backward substitution to obtain the b-spline coefficients
|
||||
j1 = 1
|
||||
do 542 j2=1,idim
|
||||
call fpbacp(g1,g2,c(j1),n7,k1,c(j1),k2,nest)
|
||||
j1 = j1+n
|
||||
542 continue
|
||||
c calculate from condition (**) the remaining b-spline coefficients.
|
||||
do 547 i=1,k
|
||||
j1 = i
|
||||
do 545 j=1,idim
|
||||
j2 = j1+n7
|
||||
c(j2) = c(j1)
|
||||
j1 = j1+n
|
||||
545 continue
|
||||
547 continue
|
||||
c computation of f(p).
|
||||
fp = 0.
|
||||
l = k1
|
||||
jj = 0
|
||||
do 570 it=1,m1
|
||||
if(u(it).lt.t(l)) go to 550
|
||||
l = l+1
|
||||
550 l0 = l-k2
|
||||
term = 0.
|
||||
do 565 j2=1,idim
|
||||
fac = 0.
|
||||
j1 = l0
|
||||
do 560 j=1,k1
|
||||
j1 = j1+1
|
||||
fac = fac+c(j1)*q(it,j)
|
||||
560 continue
|
||||
jj = jj+1
|
||||
term = term+(fac-x(jj))**2
|
||||
l0 = l0+n
|
||||
565 continue
|
||||
fp = fp+term*w(it)**2
|
||||
570 continue
|
||||
c test whether the approximation sp(u) is an acceptable solution.
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 660
|
||||
c test whether the maximal number of iterations is reached.
|
||||
if(iter.eq.maxit) go to 600
|
||||
c carry out one more step of the iteration process.
|
||||
p2 = p
|
||||
f2 = fpms
|
||||
if(ich3.ne.0) go to 580
|
||||
if((f2-f3) .gt. acc) go to 575
|
||||
c our initial choice of p is too large.
|
||||
p3 = p2
|
||||
f3 = f2
|
||||
p = p*con4
|
||||
if(p.le.p1) p = p1*con9 +p2*con1
|
||||
go to 595
|
||||
575 if(f2.lt.0.) ich3 = 1
|
||||
580 if(ich1.ne.0) go to 590
|
||||
if((f1-f2) .gt. acc) go to 585
|
||||
c our initial choice of p is too small
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
p = p/con4
|
||||
if(p3.lt.0.) go to 595
|
||||
if(p.ge.p3) p = p2*con1 +p3*con9
|
||||
go to 595
|
||||
585 if(f2.gt.0.) ich1 = 1
|
||||
c test whether the iteration process proceeds as theoretically
|
||||
c expected.
|
||||
590 if(f2.ge.f1 .or. f2.le.f3) go to 610
|
||||
c find the new value for p.
|
||||
p = fprati(p1,f1,p2,f2,p3,f3)
|
||||
595 continue
|
||||
c error codes and messages.
|
||||
600 ier = 3
|
||||
go to 660
|
||||
610 ier = 2
|
||||
go to 660
|
||||
620 ier = 1
|
||||
go to 660
|
||||
630 ier = -1
|
||||
go to 660
|
||||
640 ier = -2
|
||||
c the point (z(1),z(2),...,z(idim)) is a solution of our problem.
|
||||
c a constant function is a spline of degree k with all b-spline
|
||||
c coefficients equal to that constant.
|
||||
do 650 i=1,k1
|
||||
rn = k1-i
|
||||
t(i) = u(1)-rn*per
|
||||
j = i+k1
|
||||
rn = i-1
|
||||
t(j) = u(m)+rn*per
|
||||
650 continue
|
||||
n = nmin
|
||||
j1 = 0
|
||||
do 658 j=1,idim
|
||||
fac = z(j)
|
||||
j2 = j1
|
||||
do 654 i=1,k1
|
||||
j2 = j2+1
|
||||
c(j2) = fac
|
||||
654 continue
|
||||
j1 = j1+n
|
||||
658 continue
|
||||
fp = fp0
|
||||
fpint(n) = fp0
|
||||
fpint(n-1) = 0.
|
||||
nrdata(n) = 0
|
||||
660 return
|
||||
end
|
||||
169
cxx/fitpack/fpcoco.f
Normal file
169
cxx/fitpack/fpcoco.f
Normal file
@ -0,0 +1,169 @@
|
||||
recursive subroutine fpcoco(iopt,m,x,y,w,v,s,nest,maxtr,maxbin,
|
||||
* n,t,c,sq,sx,bind,e,wrk,lwrk,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c ..scalar arguments..
|
||||
real*8 s,sq
|
||||
integer iopt,m,nest,maxtr,maxbin,n,lwrk,kwrk,ier
|
||||
c ..array arguments..
|
||||
integer iwrk(kwrk)
|
||||
real*8 x(m),y(m),w(m),v(m),t(nest),c(nest),sx(m),e(nest),wrk(lwrk)
|
||||
*
|
||||
logical bind(nest)
|
||||
c ..local scalars..
|
||||
integer i,ia,ib,ic,iq,iu,iz,izz,i1,j,k,l,l1,m1,nmax,nr,n4,n6,n8,
|
||||
* ji,jib,jjb,jl,jr,ju,mb,nm
|
||||
real*8 sql,sqmax,term,tj,xi,half
|
||||
c ..subroutine references..
|
||||
c fpcosp,fpbspl,fpadno,fpdeno,fpseno,fpfrno
|
||||
c ..
|
||||
c set constant
|
||||
half = 0.5e0
|
||||
c determine the maximal admissible number of knots.
|
||||
nmax = m+4
|
||||
c the initial choice of knots depends on the value of iopt.
|
||||
c if iopt=0 the program starts with the minimal number of knots
|
||||
c so that can be guarantied that the concavity/convexity constraints
|
||||
c will be satisfied.
|
||||
c if iopt = 1 the program will continue from the point on where she
|
||||
c left at the foregoing call.
|
||||
if(iopt.gt.0) go to 80
|
||||
c find the minimal number of knots.
|
||||
c a knot is located at the data point x(i), i=2,3,...m-1 if
|
||||
c 1) v(i) ^= 0 and
|
||||
c 2) v(i)*v(i-1) <= 0 or v(i)*v(i+1) <= 0.
|
||||
m1 = m-1
|
||||
n = 4
|
||||
do 20 i=2,m1
|
||||
if(v(i).eq.0. .or. (v(i)*v(i-1).gt.0. .and.
|
||||
* v(i)*v(i+1).gt.0.)) go to 20
|
||||
n = n+1
|
||||
c test whether the required storage space exceeds the available one.
|
||||
if(n+4.gt.nest) go to 200
|
||||
t(n) = x(i)
|
||||
20 continue
|
||||
c find the position of the knots t(1),...t(4) and t(n-3),...t(n) which
|
||||
c are needed for the b-spline representation of s(x).
|
||||
do 30 i=1,4
|
||||
t(i) = x(1)
|
||||
n = n+1
|
||||
t(n) = x(m)
|
||||
30 continue
|
||||
c test whether the minimum number of knots exceeds the maximum number.
|
||||
if(n.gt.nmax) go to 210
|
||||
c main loop for the different sets of knots.
|
||||
c find corresponding values e(j) to the knots t(j+3),j=1,2,...n-6
|
||||
c e(j) will take the value -1,1, or 0 according to the requirement
|
||||
c that s(x) must be locally convex or concave at t(j+3) or that the
|
||||
c sign of s''(x) is unrestricted at that point.
|
||||
40 i= 1
|
||||
xi = x(1)
|
||||
j = 4
|
||||
tj = t(4)
|
||||
n6 = n-6
|
||||
do 70 l=1,n6
|
||||
50 if(xi.eq.tj) go to 60
|
||||
i = i+1
|
||||
xi = x(i)
|
||||
go to 50
|
||||
60 e(l) = v(i)
|
||||
j = j+1
|
||||
tj = t(j)
|
||||
70 continue
|
||||
c we partition the working space
|
||||
nm = n+maxbin
|
||||
mb = maxbin+1
|
||||
ia = 1
|
||||
ib = ia+4*n
|
||||
ic = ib+nm*maxbin
|
||||
iz = ic+n
|
||||
izz = iz+n
|
||||
iu = izz+n
|
||||
iq = iu+maxbin
|
||||
ji = 1
|
||||
ju = ji+maxtr
|
||||
jl = ju+maxtr
|
||||
jr = jl+maxtr
|
||||
jjb = jr+maxtr
|
||||
jib = jjb+mb
|
||||
c given the set of knots t(j),j=1,2,...n, find the least-squares cubic
|
||||
c spline which satisfies the imposed concavity/convexity constraints.
|
||||
call fpcosp(m,x,y,w,n,t,e,maxtr,maxbin,c,sq,sx,bind,nm,mb,wrk(ia),
|
||||
*
|
||||
* wrk(ib),wrk(ic),wrk(iz),wrk(izz),wrk(iu),wrk(iq),iwrk(ji),
|
||||
* iwrk(ju),iwrk(jl),iwrk(jr),iwrk(jjb),iwrk(jib),ier)
|
||||
c if sq <= s or in case of abnormal exit from fpcosp, control is
|
||||
c repassed to the driver program.
|
||||
if(sq.le.s .or. ier.gt.0) go to 300
|
||||
c calculate for each knot interval t(l-1) <= xi <= t(l) the
|
||||
c sum((wi*(yi-s(xi)))**2).
|
||||
c find the interval t(k-1) <= x <= t(k) for which this sum is maximal
|
||||
c on the condition that this interval contains at least one interior
|
||||
c data point x(nr) and that s(x) is not given there by a straight line.
|
||||
80 sqmax = 0.
|
||||
sql = 0.
|
||||
l = 5
|
||||
nr = 0
|
||||
i1 = 1
|
||||
n4 = n-4
|
||||
do 110 i=1,m
|
||||
term = (w(i)*(sx(i)-y(i)))**2
|
||||
if(x(i).lt.t(l) .or. l.gt.n4) go to 100
|
||||
term = term*half
|
||||
sql = sql+term
|
||||
if(i-i1.le.1 .or. (bind(l-4).and.bind(l-3))) go to 90
|
||||
if(sql.le.sqmax) go to 90
|
||||
k = l
|
||||
sqmax = sql
|
||||
nr = i1+(i-i1)/2
|
||||
90 l = l+1
|
||||
i1 = i
|
||||
sql = 0.
|
||||
100 sql = sql+term
|
||||
110 continue
|
||||
if(m-i1.le.1 .or. (bind(l-4).and.bind(l-3))) go to 120
|
||||
if(sql.le.sqmax) go to 120
|
||||
k = l
|
||||
nr = i1+(m-i1)/2
|
||||
c if no such interval is found, control is repassed to the driver
|
||||
c program (ier = -1).
|
||||
120 if(nr.eq.0) go to 190
|
||||
c if s(x) is given by the same straight line in two succeeding knot
|
||||
c intervals t(l-1) <= x <= t(l) and t(l) <= x <= t(l+1),delete t(l)
|
||||
n8 = n-8
|
||||
l1 = 0
|
||||
if(n8.le.0) go to 150
|
||||
do 140 i=1,n8
|
||||
if(.not. (bind(i).and.bind(i+1).and.bind(i+2))) go to 140
|
||||
l = i+4-l1
|
||||
if(k.gt.l) k = k-1
|
||||
n = n-1
|
||||
l1 = l1+1
|
||||
do 130 j=l,n
|
||||
t(j) = t(j+1)
|
||||
130 continue
|
||||
140 continue
|
||||
c test whether we cannot further increase the number of knots.
|
||||
150 if(n.eq.nmax) go to 180
|
||||
if(n.eq.nest) go to 170
|
||||
c locate an additional knot at the point x(nr).
|
||||
j = n
|
||||
do 160 i=k,n
|
||||
t(j+1) = t(j)
|
||||
j = j-1
|
||||
160 continue
|
||||
t(k) = x(nr)
|
||||
n = n+1
|
||||
c restart the computations with the new set of knots.
|
||||
go to 40
|
||||
c error codes and messages.
|
||||
170 ier = -3
|
||||
go to 300
|
||||
180 ier = -2
|
||||
go to 300
|
||||
190 ier = -1
|
||||
go to 300
|
||||
200 ier = 4
|
||||
go to 300
|
||||
210 ier = 5
|
||||
300 return
|
||||
end
|
||||
443
cxx/fitpack/fpcons.f
Normal file
443
cxx/fitpack/fpcons.f
Normal file
@ -0,0 +1,443 @@
|
||||
recursive subroutine fpcons(iopt,idim,m,u,mx,x,w,ib,ie,k,s,nest,
|
||||
* tol,maxit,k1,k2,n,t,nc,c,fp,fpint,z,a,b,g,q,nrdata,ier)
|
||||
ccc implicit none c XXX: mmnin/nmin variables on line 61
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 s,tol,fp
|
||||
integer iopt,idim,m,mx,ib,ie,k,nest,maxit,k1,k2,n,nc,ier
|
||||
c ..array arguments..
|
||||
real*8 u(m),x(mx),w(m),t(nest),c(nc),fpint(nest),
|
||||
* z(nc),a(nest,k1),b(nest,k2),g(nest,k2),q(m,k1)
|
||||
integer nrdata(nest)
|
||||
c ..local scalars..
|
||||
real*8 acc,con1,con4,con9,cos,fac,fpart,fpms,fpold,fp0,f1,f2,f3,
|
||||
* half,one,p,pinv,piv,p1,p2,p3,rn,sin,store,term,ui,wi
|
||||
integer i,ich1,ich3,it,iter,i1,i2,i3,j,jb,je,jj,j1,j2,j3,kbe,
|
||||
* l,li,lj,l0,mb,me,mm,new,nk1,nmax,nmin,nn,nplus,npl1,nrint,n8
|
||||
c ..local arrays..
|
||||
real*8 h(7),xi(10)
|
||||
c ..function references
|
||||
real*8 abs,fprati
|
||||
integer max0,min0
|
||||
c ..subroutine references..
|
||||
c fpbacp,fpbspl,fpgivs,fpdisc,fpknot,fprota
|
||||
c ..
|
||||
c set constants
|
||||
one = 0.1e+01
|
||||
con1 = 0.1e0
|
||||
con9 = 0.9e0
|
||||
con4 = 0.4e-01
|
||||
half = 0.5e0
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 1: determination of the number of knots and their position c
|
||||
c ************************************************************** c
|
||||
c given a set of knots we compute the least-squares curve sinf(u), c
|
||||
c and the corresponding sum of squared residuals fp=f(p=inf). c
|
||||
c if iopt=-1 sinf(u) is the requested curve. c
|
||||
c if iopt=0 or iopt=1 we check whether we can accept the knots: c
|
||||
c if fp <=s we will continue with the current set of knots. c
|
||||
c if fp > s we will increase the number of knots and compute the c
|
||||
c corresponding least-squares curve until finally fp<=s. c
|
||||
c the initial choice of knots depends on the value of s and iopt. c
|
||||
c if s=0 we have spline interpolation; in that case the number of c
|
||||
c knots equals nmax = m+k+1-max(0,ib-1)-max(0,ie-1) c
|
||||
c if s > 0 and c
|
||||
c iopt=0 we first compute the least-squares polynomial curve of c
|
||||
c degree k; n = nmin = 2*k+2 c
|
||||
c iopt=1 we start with the set of knots found at the last c
|
||||
c call of the routine, except for the case that s > fp0; then c
|
||||
c we compute directly the polynomial curve of degree k. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c determine nmin, the number of knots for polynomial approximation.
|
||||
nmin = 2*k1
|
||||
c find which data points are to be considered.
|
||||
mb = 2
|
||||
jb = ib
|
||||
if(ib.gt.0) go to 10
|
||||
mb = 1
|
||||
jb = 1
|
||||
10 me = m-1
|
||||
je = ie
|
||||
if(ie.gt.0) go to 20
|
||||
me = m
|
||||
je = 1
|
||||
20 if(iopt.lt.0) go to 60
|
||||
c calculation of acc, the absolute tolerance for the root of f(p)=s.
|
||||
acc = tol*s
|
||||
c determine nmax, the number of knots for spline interpolation.
|
||||
kbe = k1-jb-je
|
||||
mmin = kbe+2
|
||||
mm = m-mmin
|
||||
nmax = nmin+mm
|
||||
if(s.gt.0.) go to 40
|
||||
c if s=0, s(u) is an interpolating curve.
|
||||
c test whether the required storage space exceeds the available one.
|
||||
n = nmax
|
||||
if(nmax.gt.nest) go to 420
|
||||
c find the position of the interior knots in case of interpolation.
|
||||
if(mm.eq.0) go to 60
|
||||
25 i = k2
|
||||
j = 3-jb+k/2
|
||||
do 30 l=1,mm
|
||||
t(i) = u(j)
|
||||
i = i+1
|
||||
j = j+1
|
||||
30 continue
|
||||
go to 60
|
||||
c if s>0 our initial choice of knots depends on the value of iopt.
|
||||
c if iopt=0 or iopt=1 and s>=fp0, we start computing the least-squares
|
||||
c polynomial curve which is a spline curve without interior knots.
|
||||
c if iopt=1 and fp0>s we start computing the least squares spline curve
|
||||
c according to the set of knots found at the last call of the routine.
|
||||
40 if(iopt.eq.0) go to 50
|
||||
if(n.eq.nmin) go to 50
|
||||
fp0 = fpint(n)
|
||||
fpold = fpint(n-1)
|
||||
nplus = nrdata(n)
|
||||
if(fp0.gt.s) go to 60
|
||||
50 n = nmin
|
||||
fpold = 0.
|
||||
nplus = 0
|
||||
nrdata(1) = m-2
|
||||
c main loop for the different sets of knots. m is a save upper bound
|
||||
c for the number of trials.
|
||||
60 do 200 iter = 1,m
|
||||
if(n.eq.nmin) ier = -2
|
||||
c find nrint, tne number of knot intervals.
|
||||
nrint = n-nmin+1
|
||||
c find the position of the additional knots which are needed for
|
||||
c the b-spline representation of s(u).
|
||||
nk1 = n-k1
|
||||
i = n
|
||||
do 70 j=1,k1
|
||||
t(j) = u(1)
|
||||
t(i) = u(m)
|
||||
i = i-1
|
||||
70 continue
|
||||
c compute the b-spline coefficients of the least-squares spline curve
|
||||
c sinf(u). the observation matrix a is built up row by row and
|
||||
c reduced to upper triangular form by givens transformations.
|
||||
c at the same time fp=f(p=inf) is computed.
|
||||
fp = 0.
|
||||
c nn denotes the dimension of the splines
|
||||
nn = nk1-ib-ie
|
||||
c initialize the b-spline coefficients and the observation matrix a.
|
||||
do 75 i=1,nc
|
||||
z(i) = 0.
|
||||
c(i) = 0.
|
||||
75 continue
|
||||
if(me.lt.mb) go to 134
|
||||
if(nn.eq.0) go to 82
|
||||
do 80 i=1,nn
|
||||
do 80 j=1,k1
|
||||
a(i,j) = 0.
|
||||
80 continue
|
||||
82 l = k1
|
||||
jj = (mb-1)*idim
|
||||
do 130 it=mb,me
|
||||
c fetch the current data point u(it),x(it).
|
||||
ui = u(it)
|
||||
wi = w(it)
|
||||
do 84 j=1,idim
|
||||
jj = jj+1
|
||||
xi(j) = x(jj)*wi
|
||||
84 continue
|
||||
c search for knot interval t(l) <= ui < t(l+1).
|
||||
86 if(ui.lt.t(l+1) .or. l.eq.nk1) go to 90
|
||||
l = l+1
|
||||
go to 86
|
||||
c evaluate the (k+1) non-zero b-splines at ui and store them in q.
|
||||
90 call fpbspl(t,n,k,ui,l,h)
|
||||
do 92 i=1,k1
|
||||
q(it,i) = h(i)
|
||||
h(i) = h(i)*wi
|
||||
92 continue
|
||||
c take into account that certain b-spline coefficients must be zero.
|
||||
lj = k1
|
||||
j = nk1-l-ie
|
||||
if(j.ge.0) go to 94
|
||||
lj = lj+j
|
||||
94 li = 1
|
||||
j = l-k1-ib
|
||||
if(j.ge.0) go to 96
|
||||
li = li-j
|
||||
j = 0
|
||||
96 if(li.gt.lj) go to 120
|
||||
c rotate the new row of the observation matrix into triangle.
|
||||
do 110 i=li,lj
|
||||
j = j+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 110
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a(j,1),cos,sin)
|
||||
c transformations to right hand side.
|
||||
j1 = j
|
||||
do 98 j2 =1,idim
|
||||
call fprota(cos,sin,xi(j2),z(j1))
|
||||
j1 = j1+n
|
||||
98 continue
|
||||
if(i.eq.lj) go to 120
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 100 i1 = i3,lj
|
||||
i2 = i2+1
|
||||
c transformations to left hand side.
|
||||
call fprota(cos,sin,h(i1),a(j,i2))
|
||||
100 continue
|
||||
110 continue
|
||||
c add contribution of this row to the sum of squares of residual
|
||||
c right hand sides.
|
||||
120 do 125 j2=1,idim
|
||||
fp = fp+xi(j2)**2
|
||||
125 continue
|
||||
130 continue
|
||||
if(ier.eq.(-2)) fp0 = fp
|
||||
fpint(n) = fp0
|
||||
fpint(n-1) = fpold
|
||||
nrdata(n) = nplus
|
||||
c backward substitution to obtain the b-spline coefficients.
|
||||
if(nn.eq.0) go to 134
|
||||
j1 = 1
|
||||
do 132 j2=1,idim
|
||||
j3 = j1+ib
|
||||
call fpback(a,z(j1),nn,k1,c(j3),nest)
|
||||
j1 = j1+n
|
||||
132 continue
|
||||
c test whether the approximation sinf(u) is an acceptable solution.
|
||||
134 if(iopt.lt.0) go to 440
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 440
|
||||
c if f(p=inf) < s accept the choice of knots.
|
||||
if(fpms.lt.0.) go to 250
|
||||
c if n = nmax, sinf(u) is an interpolating spline curve.
|
||||
if(n.eq.nmax) go to 430
|
||||
c increase the number of knots.
|
||||
c if n=nest we cannot increase the number of knots because of
|
||||
c the storage capacity limitation.
|
||||
if(n.eq.nest) go to 420
|
||||
c determine the number of knots nplus we are going to add.
|
||||
if(ier.eq.0) go to 140
|
||||
nplus = 1
|
||||
ier = 0
|
||||
go to 150
|
||||
140 npl1 = nplus*2
|
||||
rn = nplus
|
||||
if(fpold-fp.gt.acc) npl1 = rn*fpms/(fpold-fp)
|
||||
nplus = min0(nplus*2,max0(npl1,nplus/2,1))
|
||||
150 fpold = fp
|
||||
c compute the sum of squared residuals for each knot interval
|
||||
c t(j+k) <= u(i) <= t(j+k+1) and store it in fpint(j),j=1,2,...nrint.
|
||||
fpart = 0.
|
||||
i = 1
|
||||
l = k2
|
||||
new = 0
|
||||
jj = (mb-1)*idim
|
||||
do 180 it=mb,me
|
||||
if(u(it).lt.t(l) .or. l.gt.nk1) go to 160
|
||||
new = 1
|
||||
l = l+1
|
||||
160 term = 0.
|
||||
l0 = l-k2
|
||||
do 175 j2=1,idim
|
||||
fac = 0.
|
||||
j1 = l0
|
||||
do 170 j=1,k1
|
||||
j1 = j1+1
|
||||
fac = fac+c(j1)*q(it,j)
|
||||
170 continue
|
||||
jj = jj+1
|
||||
term = term+(w(it)*(fac-x(jj)))**2
|
||||
l0 = l0+n
|
||||
175 continue
|
||||
fpart = fpart+term
|
||||
if(new.eq.0) go to 180
|
||||
store = term*half
|
||||
fpint(i) = fpart-store
|
||||
i = i+1
|
||||
fpart = store
|
||||
new = 0
|
||||
180 continue
|
||||
fpint(nrint) = fpart
|
||||
do 190 l=1,nplus
|
||||
c add a new knot.
|
||||
call fpknot(u,m,t,n,fpint,nrdata,nrint,nest,1)
|
||||
c if n=nmax we locate the knots as for interpolation
|
||||
if(n.eq.nmax) go to 25
|
||||
c test whether we cannot further increase the number of knots.
|
||||
if(n.eq.nest) go to 200
|
||||
190 continue
|
||||
c restart the computations with the new set of knots.
|
||||
200 continue
|
||||
c test whether the least-squares kth degree polynomial curve is a
|
||||
c solution of our approximation problem.
|
||||
250 if(ier.eq.(-2)) go to 440
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 2: determination of the smoothing spline curve sp(u). c
|
||||
c ********************************************************** c
|
||||
c we have determined the number of knots and their position. c
|
||||
c we now compute the b-spline coefficients of the smoothing curve c
|
||||
c sp(u). the observation matrix a is extended by the rows of matrix c
|
||||
c b expressing that the kth derivative discontinuities of sp(u) at c
|
||||
c the interior knots t(k+2),...t(n-k-1) must be zero. the corres- c
|
||||
c ponding weights of these additional rows are set to 1/p. c
|
||||
c iteratively we then have to determine the value of p such that f(p),c
|
||||
c the sum of squared residuals be = s. we already know that the least c
|
||||
c squares kth degree polynomial curve corresponds to p=0, and that c
|
||||
c the least-squares spline curve corresponds to p=infinity. the c
|
||||
c iteration process which is proposed here, makes use of rational c
|
||||
c interpolation. since f(p) is a convex and strictly decreasing c
|
||||
c function of p, it can be approximated by a rational function c
|
||||
c r(p) = (u*p+v)/(p+w). three values of p(p1,p2,p3) with correspond- c
|
||||
c ing values of f(p) (f1=f(p1)-s,f2=f(p2)-s,f3=f(p3)-s) are used c
|
||||
c to calculate the new value of p such that r(p)=s. convergence is c
|
||||
c guaranteed by taking f1>0 and f3<0. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c evaluate the discontinuity jump of the kth derivative of the
|
||||
c b-splines at the knots t(l),l=k+2,...n-k-1 and store in b.
|
||||
call fpdisc(t,n,k2,b,nest)
|
||||
c initial value for p.
|
||||
p1 = 0.
|
||||
f1 = fp0-s
|
||||
p3 = -one
|
||||
f3 = fpms
|
||||
p = 0.
|
||||
do 252 i=1,nn
|
||||
p = p+a(i,1)
|
||||
252 continue
|
||||
rn = nn
|
||||
p = rn/p
|
||||
ich1 = 0
|
||||
ich3 = 0
|
||||
n8 = n-nmin
|
||||
c iteration process to find the root of f(p) = s.
|
||||
do 360 iter=1,maxit
|
||||
c the rows of matrix b with weight 1/p are rotated into the
|
||||
c triangularised observation matrix a which is stored in g.
|
||||
pinv = one/p
|
||||
do 255 i=1,nc
|
||||
c(i) = z(i)
|
||||
255 continue
|
||||
do 260 i=1,nn
|
||||
g(i,k2) = 0.
|
||||
do 260 j=1,k1
|
||||
g(i,j) = a(i,j)
|
||||
260 continue
|
||||
do 300 it=1,n8
|
||||
c the row of matrix b is rotated into triangle by givens transformation
|
||||
do 264 i=1,k2
|
||||
h(i) = b(it,i)*pinv
|
||||
264 continue
|
||||
do 268 j=1,idim
|
||||
xi(j) = 0.
|
||||
268 continue
|
||||
c take into account that certain b-spline coefficients must be zero.
|
||||
if(it.gt.ib) go to 274
|
||||
j1 = ib-it+2
|
||||
j2 = 1
|
||||
do 270 i=j1,k2
|
||||
h(j2) = h(i)
|
||||
j2 = j2+1
|
||||
270 continue
|
||||
do 272 i=j2,k2
|
||||
h(i) = 0.
|
||||
272 continue
|
||||
274 jj = max0(1,it-ib)
|
||||
do 290 j=jj,nn
|
||||
piv = h(1)
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,g(j,1),cos,sin)
|
||||
c transformations to right hand side.
|
||||
j1 = j
|
||||
do 277 j2=1,idim
|
||||
call fprota(cos,sin,xi(j2),c(j1))
|
||||
j1 = j1+n
|
||||
277 continue
|
||||
if(j.eq.nn) go to 300
|
||||
i2 = min0(nn-j,k1)
|
||||
do 280 i=1,i2
|
||||
c transformations to left hand side.
|
||||
i1 = i+1
|
||||
call fprota(cos,sin,h(i1),g(j,i1))
|
||||
h(i) = h(i1)
|
||||
280 continue
|
||||
h(i2+1) = 0.
|
||||
290 continue
|
||||
300 continue
|
||||
c backward substitution to obtain the b-spline coefficients.
|
||||
j1 = 1
|
||||
do 308 j2=1,idim
|
||||
j3 = j1+ib
|
||||
call fpback(g,c(j1),nn,k2,c(j3),nest)
|
||||
if(ib.eq.0) go to 306
|
||||
j3 = j1
|
||||
do 304 i=1,ib
|
||||
c(j3) = 0.
|
||||
j3 = j3+1
|
||||
304 continue
|
||||
306 j1 =j1+n
|
||||
308 continue
|
||||
c computation of f(p).
|
||||
fp = 0.
|
||||
l = k2
|
||||
jj = (mb-1)*idim
|
||||
do 330 it=mb,me
|
||||
if(u(it).lt.t(l) .or. l.gt.nk1) go to 310
|
||||
l = l+1
|
||||
310 l0 = l-k2
|
||||
term = 0.
|
||||
do 325 j2=1,idim
|
||||
fac = 0.
|
||||
j1 = l0
|
||||
do 320 j=1,k1
|
||||
j1 = j1+1
|
||||
fac = fac+c(j1)*q(it,j)
|
||||
320 continue
|
||||
jj = jj+1
|
||||
term = term+(fac-x(jj))**2
|
||||
l0 = l0+n
|
||||
325 continue
|
||||
fp = fp+term*w(it)**2
|
||||
330 continue
|
||||
c test whether the approximation sp(u) is an acceptable solution.
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 440
|
||||
c test whether the maximal number of iterations is reached.
|
||||
if(iter.eq.maxit) go to 400
|
||||
c carry out one more step of the iteration process.
|
||||
p2 = p
|
||||
f2 = fpms
|
||||
if(ich3.ne.0) go to 340
|
||||
if((f2-f3).gt.acc) go to 335
|
||||
c our initial choice of p is too large.
|
||||
p3 = p2
|
||||
f3 = f2
|
||||
p = p*con4
|
||||
if(p.le.p1) p=p1*con9 + p2*con1
|
||||
go to 360
|
||||
335 if(f2.lt.0.) ich3=1
|
||||
340 if(ich1.ne.0) go to 350
|
||||
if((f1-f2).gt.acc) go to 345
|
||||
c our initial choice of p is too small
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
p = p/con4
|
||||
if(p3.lt.0.) go to 360
|
||||
if(p.ge.p3) p = p2*con1 + p3*con9
|
||||
go to 360
|
||||
345 if(f2.gt.0.) ich1=1
|
||||
c test whether the iteration process proceeds as theoretically
|
||||
c expected.
|
||||
350 if(f2.ge.f1 .or. f2.le.f3) go to 410
|
||||
c find the new value for p.
|
||||
p = fprati(p1,f1,p2,f2,p3,f3)
|
||||
360 continue
|
||||
c error codes and messages.
|
||||
400 ier = 3
|
||||
go to 440
|
||||
410 ier = 2
|
||||
go to 440
|
||||
420 ier = 1
|
||||
go to 440
|
||||
430 ier = -1
|
||||
440 return
|
||||
end
|
||||
363
cxx/fitpack/fpcosp.f
Normal file
363
cxx/fitpack/fpcosp.f
Normal file
@ -0,0 +1,363 @@
|
||||
recursive subroutine fpcosp(m,x,y,w,n,t,e,maxtr,maxbin,c,sq,sx,
|
||||
* bind,nm,mb,a,
|
||||
* b,const,z,zz,u,q,info,up,left,right,jbind,ibind,ier)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 sq
|
||||
integer m,n,maxtr,maxbin,nm,mb,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),y(m),w(m),t(n),e(n),c(n),sx(m),a(n,4),b(nm,maxbin),
|
||||
* const(n),z(n),zz(n),u(maxbin),q(m,4)
|
||||
integer info(maxtr),up(maxtr),left(maxtr),right(maxtr),jbind(mb),
|
||||
* ibind(mb)
|
||||
logical bind(n)
|
||||
c ..local scalars..
|
||||
integer count,i,i1,j,j1,j2,j3,k,kdim,k1,k2,k3,k4,k5,k6,
|
||||
* l,lp1,l1,l2,l3,merk,nbind,number,n1,n4,n6
|
||||
real*8 f,wi,xi
|
||||
c ..local array..
|
||||
real*8 h(4)
|
||||
c ..subroutine references..
|
||||
c fpbspl,fpadno,fpdeno,fpfrno,fpseno
|
||||
c ..
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c if we use the b-spline representation of s(x) our approximation c
|
||||
c problem results in a quadratic programming problem: c
|
||||
c find the b-spline coefficients c(j),j=1,2,...n-4 such that c
|
||||
c (1) sumi((wi*(yi-sumj(cj*nj(xi))))**2),i=1,2,...m is minimal c
|
||||
c (2) sumj(cj*n''j(t(l+3)))*e(l) <= 0, l=1,2,...n-6. c
|
||||
c to solve this problem we use the theil-van de panne procedure. c
|
||||
c if the inequality constraints (2) are numbered from 1 to n-6, c
|
||||
c this algorithm finds a subset of constraints ibind(1)..ibind(nbind) c
|
||||
c such that the solution of the minimization problem (1) with these c
|
||||
c constraints in equality form, satisfies all constraints. such a c
|
||||
c feasible solution is optimal if the lagrange parameters associated c
|
||||
c with that problem with equality constraints, are all positive. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c determine n6, the number of inequality constraints.
|
||||
n6 = n-6
|
||||
c fix the parameters which determine these constraints.
|
||||
do 10 i=1,n6
|
||||
const(i) = e(i)*(t(i+4)-t(i+1))/(t(i+5)-t(i+2))
|
||||
10 continue
|
||||
c initialize the triply linked tree which is used to find the subset
|
||||
c of constraints ibind(1),...ibind(nbind).
|
||||
count = 1
|
||||
info(1) = 0
|
||||
left(1) = 0
|
||||
right(1) = 0
|
||||
up(1) = 1
|
||||
merk = 1
|
||||
c set up the normal equations n'nc=n'y where n denotes the m x (n-4)
|
||||
c observation matrix with elements ni,j = wi*nj(xi) and y is the
|
||||
c column vector with elements yi*wi.
|
||||
c from the properties of the b-splines nj(x),j=1,2,...n-4, it follows
|
||||
c that n'n is a (n-4) x (n-4) positive definite bandmatrix of
|
||||
c bandwidth 7. the matrices n'n and n'y are built up in a and z.
|
||||
n4 = n-4
|
||||
c initialization
|
||||
do 20 i=1,n4
|
||||
z(i) = 0.
|
||||
do 20 j=1,4
|
||||
a(i,j) = 0.
|
||||
20 continue
|
||||
l = 4
|
||||
lp1 = l+1
|
||||
do 70 i=1,m
|
||||
c fetch the current row of the observation matrix.
|
||||
xi = x(i)
|
||||
wi = w(i)**2
|
||||
c search for knot interval t(l) <= xi < t(l+1)
|
||||
30 if(xi.lt.t(lp1) .or. l.eq.n4) go to 40
|
||||
l = lp1
|
||||
lp1 = l+1
|
||||
go to 30
|
||||
c evaluate the four non-zero cubic b-splines nj(xi),j=l-3,...l.
|
||||
40 call fpbspl(t,n,3,xi,l,h)
|
||||
c store in q these values h(1),h(2),...h(4).
|
||||
do 50 j=1,4
|
||||
q(i,j) = h(j)
|
||||
50 continue
|
||||
c add the contribution of the current row of the observation matrix
|
||||
c n to the normal equations.
|
||||
l3 = l-3
|
||||
k1 = 0
|
||||
do 60 j1 = l3,l
|
||||
k1 = k1+1
|
||||
f = h(k1)
|
||||
z(j1) = z(j1)+f*wi*y(i)
|
||||
k2 = k1
|
||||
j2 = 4
|
||||
do 60 j3 = j1,l
|
||||
a(j3,j2) = a(j3,j2)+f*wi*h(k2)
|
||||
k2 = k2+1
|
||||
j2 = j2-1
|
||||
60 continue
|
||||
70 continue
|
||||
c since n'n is a symmetric matrix it can be factorized as
|
||||
c (3) n'n = (r1)'(d1)(r1)
|
||||
c with d1 a diagonal matrix and r1 an (n-4) x (n-4) unit upper
|
||||
c triangular matrix of bandwidth 4. the matrices r1 and d1 are built
|
||||
c up in a. at the same time we solve the systems of equations
|
||||
c (4) (r1)'(z2) = n'y
|
||||
c (5) (d1) (z1) = (z2)
|
||||
c the vectors z2 and z1 are kept in zz and z.
|
||||
do 140 i=1,n4
|
||||
k1 = 1
|
||||
if(i.lt.4) k1 = 5-i
|
||||
k2 = i-4+k1
|
||||
k3 = k2
|
||||
do 100 j=k1,4
|
||||
k4 = j-1
|
||||
k5 = 4-j+k1
|
||||
f = a(i,j)
|
||||
if(k1.gt.k4) go to 90
|
||||
k6 = k2
|
||||
do 80 k=k1,k4
|
||||
f = f-a(i,k)*a(k3,k5)*a(k6,4)
|
||||
k5 = k5+1
|
||||
k6 = k6+1
|
||||
80 continue
|
||||
90 if(j.eq.4) go to 110
|
||||
a(i,j) = f/a(k3,4)
|
||||
k3 = k3+1
|
||||
100 continue
|
||||
110 a(i,4) = f
|
||||
f = z(i)
|
||||
if(i.eq.1) go to 130
|
||||
k4 = i
|
||||
do 120 j=k1,3
|
||||
k = k1+3-j
|
||||
k4 = k4-1
|
||||
f = f-a(i,k)*z(k4)*a(k4,4)
|
||||
120 continue
|
||||
130 z(i) = f/a(i,4)
|
||||
zz(i) = f
|
||||
140 continue
|
||||
c start computing the least-squares cubic spline without taking account
|
||||
c of any constraint.
|
||||
nbind = 0
|
||||
n1 = 1
|
||||
ibind(1) = 0
|
||||
c main loop for the least-squares problems with different subsets of
|
||||
c the constraints (2) in equality form. the resulting b-spline coeff.
|
||||
c c and lagrange parameters u are the solution of the system
|
||||
c ! n'n b' ! ! c ! ! n'y !
|
||||
c (6) ! ! ! ! = ! !
|
||||
c ! b 0 ! ! u ! ! 0 !
|
||||
c z1 is stored into array c.
|
||||
150 do 160 i=1,n4
|
||||
c(i) = z(i)
|
||||
160 continue
|
||||
c if there are no equality constraints, compute the coeff. c directly.
|
||||
if(nbind.eq.0) go to 370
|
||||
c initialization
|
||||
kdim = n4+nbind
|
||||
do 170 i=1,nbind
|
||||
do 170 j=1,kdim
|
||||
b(j,i) = 0.
|
||||
170 continue
|
||||
c matrix b is built up,expressing that the constraints nrs ibind(1),...
|
||||
c ibind(nbind) must be satisfied in equality form.
|
||||
do 180 i=1,nbind
|
||||
l = ibind(i)
|
||||
b(l,i) = e(l)
|
||||
b(l+1,i) = -(e(l)+const(l))
|
||||
b(l+2,i) = const(l)
|
||||
180 continue
|
||||
c find the matrix (b1) as the solution of the system of equations
|
||||
c (7) (r1)'(d1)(b1) = b'
|
||||
c (b1) is built up in the upper part of the array b(rows 1,...n-4).
|
||||
do 220 k1=1,nbind
|
||||
l = ibind(k1)
|
||||
do 210 i=l,n4
|
||||
f = b(i,k1)
|
||||
if(i.eq.1) go to 200
|
||||
k2 = 3
|
||||
if(i.lt.4) k2 = i-1
|
||||
do 190 k3=1,k2
|
||||
l1 = i-k3
|
||||
l2 = 4-k3
|
||||
f = f-b(l1,k1)*a(i,l2)*a(l1,4)
|
||||
190 continue
|
||||
200 b(i,k1) = f/a(i,4)
|
||||
210 continue
|
||||
220 continue
|
||||
c factorization of the symmetric matrix -(b1)'(d1)(b1)
|
||||
c (8) -(b1)'(d1)(b1) = (r2)'(d2)(r2)
|
||||
c with (d2) a diagonal matrix and (r2) an nbind x nbind unit upper
|
||||
c triangular matrix. the matrices r2 and d2 are built up in the lower
|
||||
c part of the array b (rows n-3,n-2,...n-4+nbind).
|
||||
do 270 i=1,nbind
|
||||
i1 = i-1
|
||||
do 260 j=i,nbind
|
||||
f = 0.
|
||||
do 230 k=1,n4
|
||||
f = f+b(k,i)*b(k,j)*a(k,4)
|
||||
230 continue
|
||||
k1 = n4+1
|
||||
if(i1.eq.0) go to 250
|
||||
do 240 k=1,i1
|
||||
f = f+b(k1,i)*b(k1,j)*b(k1,k)
|
||||
k1 = k1+1
|
||||
240 continue
|
||||
250 b(k1,j) = -f
|
||||
if(j.eq.i) go to 260
|
||||
b(k1,j) = b(k1,j)/b(k1,i)
|
||||
260 continue
|
||||
270 continue
|
||||
c according to (3),(7) and (8) the system of equations (6) becomes
|
||||
c ! (r1)' 0 ! ! (d1) 0 ! ! (r1) (b1) ! ! c ! ! n'y !
|
||||
c (9) ! ! ! ! ! ! ! ! = ! !
|
||||
c ! (b1)' (r2)'! ! 0 (d2) ! ! 0 (r2) ! ! u ! ! 0 !
|
||||
c backward substitution to obtain the b-spline coefficients c(j),j=1,..
|
||||
c n-4 and the lagrange parameters u(j),j=1,2,...nbind.
|
||||
c first step of the backward substitution: solve the system
|
||||
c ! (r1)'(d1) 0 ! ! (c1) ! ! n'y !
|
||||
c (10) ! ! ! ! = ! !
|
||||
c ! (b1)'(d1) (r2)'(d2) ! ! (u1) ! ! 0 !
|
||||
c from (4) and (5) we know that this is equivalent to
|
||||
c (11) (c1) = (z1)
|
||||
c (12) (r2)'(d2)(u1) = -(b1)'(z2)
|
||||
do 310 i=1,nbind
|
||||
f = 0.
|
||||
do 280 j=1,n4
|
||||
f = f+b(j,i)*zz(j)
|
||||
280 continue
|
||||
i1 = i-1
|
||||
k1 = n4+1
|
||||
if(i1.eq.0) go to 300
|
||||
do 290 j=1,i1
|
||||
f = f+u(j)*b(k1,i)*b(k1,j)
|
||||
k1 = k1+1
|
||||
290 continue
|
||||
300 u(i) = -f/b(k1,i)
|
||||
310 continue
|
||||
c second step of the backward substitution: solve the system
|
||||
c ! (r1) (b1) ! ! c ! ! c1 !
|
||||
c (13) ! ! ! ! = ! !
|
||||
c ! 0 (r2) ! ! u ! ! u1 !
|
||||
k1 = nbind
|
||||
k2 = kdim
|
||||
c find the lagrange parameters u.
|
||||
do 340 i=1,nbind
|
||||
f = u(k1)
|
||||
if(i.eq.1) go to 330
|
||||
k3 = k1+1
|
||||
do 320 j=k3,nbind
|
||||
f = f-u(j)*b(k2,j)
|
||||
320 continue
|
||||
330 u(k1) = f
|
||||
k1 = k1-1
|
||||
k2 = k2-1
|
||||
340 continue
|
||||
c find the b-spline coefficients c.
|
||||
do 360 i=1,n4
|
||||
f = c(i)
|
||||
do 350 j=1,nbind
|
||||
f = f-u(j)*b(i,j)
|
||||
350 continue
|
||||
c(i) = f
|
||||
360 continue
|
||||
370 k1 = n4
|
||||
do 390 i=2,n4
|
||||
k1 = k1-1
|
||||
f = c(k1)
|
||||
k2 = 1
|
||||
if(i.lt.5) k2 = 5-i
|
||||
k3 = k1
|
||||
l = 3
|
||||
do 380 j=k2,3
|
||||
k3 = k3+1
|
||||
f = f-a(k3,l)*c(k3)
|
||||
l = l-1
|
||||
380 continue
|
||||
c(k1) = f
|
||||
390 continue
|
||||
c test whether the solution of the least-squares problem with the
|
||||
c constraints ibind(1),...ibind(nbind) in equality form, satisfies
|
||||
c all of the constraints (2).
|
||||
k = 1
|
||||
c number counts the number of violated inequality constraints.
|
||||
number = 0
|
||||
do 440 j=1,n6
|
||||
l = ibind(k)
|
||||
k = k+1
|
||||
if(j.eq.l) go to 440
|
||||
k = k-1
|
||||
c test whether constraint j is satisfied
|
||||
f = e(j)*(c(j)-c(j+1))+const(j)*(c(j+2)-c(j+1))
|
||||
if(f.le.0.) go to 440
|
||||
c if constraint j is not satisfied, add a branch of length nbind+1
|
||||
c to the tree. the nodes of this branch contain in their information
|
||||
c field the number of the constraints ibind(1),...ibind(nbind) and j,
|
||||
c arranged in increasing order.
|
||||
number = number+1
|
||||
k1 = k-1
|
||||
if(k1.eq.0) go to 410
|
||||
do 400 i=1,k1
|
||||
jbind(i) = ibind(i)
|
||||
400 continue
|
||||
410 jbind(k) = j
|
||||
if(l.eq.0) go to 430
|
||||
do 420 i=k,nbind
|
||||
jbind(i+1) = ibind(i)
|
||||
420 continue
|
||||
430 call fpadno(maxtr,up,left,right,info,count,merk,jbind,n1,ier)
|
||||
c test whether the storage space which is required for the tree,exceeds
|
||||
c the available storage space.
|
||||
if(ier.ne.0) go to 560
|
||||
440 continue
|
||||
c test whether the solution of the least-squares problem with equality
|
||||
c constraints is a feasible solution.
|
||||
if(number.eq.0) go to 470
|
||||
c test whether there are still cases with nbind constraints in
|
||||
c equality form to be considered.
|
||||
450 if(merk.gt.1) go to 460
|
||||
nbind = n1
|
||||
c test whether the number of knots where s''(x)=0 exceeds maxbin.
|
||||
if(nbind.gt.maxbin) go to 550
|
||||
n1 = n1+1
|
||||
ibind(n1) = 0
|
||||
c search which cases with nbind constraints in equality form
|
||||
c are going to be considered.
|
||||
call fpdeno(maxtr,up,left,right,nbind,merk)
|
||||
c test whether the quadratic programming problem has a solution.
|
||||
if(merk.eq.1) go to 570
|
||||
c find a new case with nbind constraints in equality form.
|
||||
460 call fpseno(maxtr,up,left,right,info,merk,ibind,nbind)
|
||||
go to 150
|
||||
c test whether the feasible solution is optimal.
|
||||
470 ier = 0
|
||||
do 480 i=1,n6
|
||||
bind(i) = .false.
|
||||
480 continue
|
||||
if(nbind.eq.0) go to 500
|
||||
do 490 i=1,nbind
|
||||
if(u(i).le.0.) go to 450
|
||||
j = ibind(i)
|
||||
bind(j) = .true.
|
||||
490 continue
|
||||
c evaluate s(x) at the data points x(i) and calculate the weighted
|
||||
c sum of squared residual right hand sides sq.
|
||||
500 sq = 0.
|
||||
l = 4
|
||||
lp1 = 5
|
||||
do 530 i=1,m
|
||||
510 if(x(i).lt.t(lp1) .or. l.eq.n4) go to 520
|
||||
l = lp1
|
||||
lp1 = l+1
|
||||
go to 510
|
||||
520 sx(i) = c(l-3)*q(i,1)+c(l-2)*q(i,2)+c(l-1)*q(i,3)+c(l)*q(i,4)
|
||||
sq = sq+(w(i)*(y(i)-sx(i)))**2
|
||||
530 continue
|
||||
go to 600
|
||||
c error codes and messages.
|
||||
550 ier = 1
|
||||
go to 600
|
||||
560 ier = 2
|
||||
go to 600
|
||||
570 ier = 3
|
||||
600 return
|
||||
end
|
||||
57
cxx/fitpack/fpcsin.f
Normal file
57
cxx/fitpack/fpcsin.f
Normal file
@ -0,0 +1,57 @@
|
||||
recursive subroutine fpcsin(a,b,par,sia,coa,sib,cob,ress,resc)
|
||||
implicit none
|
||||
c fpcsin calculates the integrals ress=integral((b-x)**3*sin(par*x))
|
||||
c and resc=integral((b-x)**3*cos(par*x)) over the interval (a,b),
|
||||
c given sia=sin(par*a),coa=cos(par*a),sib=sin(par*b) and cob=cos(par*b)
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 a,b,par,sia,coa,sib,cob,ress,resc
|
||||
c ..local scalars..
|
||||
integer i,j
|
||||
real*8 ab,ab4,ai,alfa,beta,b2,b4,eps,fac,f1,f2,one,quart,six,
|
||||
* three,two
|
||||
c ..function references..
|
||||
real*8 abs
|
||||
c ..
|
||||
one = 0.1e+01
|
||||
two = 0.2e+01
|
||||
three = 0.3e+01
|
||||
six = 0.6e+01
|
||||
quart = 0.25e+0
|
||||
eps = 0.1e-09
|
||||
ab = b-a
|
||||
ab4 = ab**4
|
||||
alfa = ab*par
|
||||
c the way of calculating the integrals ress and resc depends on
|
||||
c the value of alfa = (b-a)*par.
|
||||
if(abs(alfa).le.one) go to 100
|
||||
c integration by parts.
|
||||
beta = one/alfa
|
||||
b2 = beta**2
|
||||
b4 = six*b2**2
|
||||
f1 = three*b2*(one-two*b2)
|
||||
f2 = beta*(one-six*b2)
|
||||
ress = ab4*(coa*f2+sia*f1+sib*b4)
|
||||
resc = ab4*(coa*f1-sia*f2+cob*b4)
|
||||
go to 400
|
||||
c ress and resc are found by evaluating a series expansion.
|
||||
100 fac = quart
|
||||
f1 = fac
|
||||
f2 = 0.
|
||||
i = 4
|
||||
do 200 j=1,5
|
||||
i = i+1
|
||||
ai = i
|
||||
fac = fac*alfa/ai
|
||||
f2 = f2+fac
|
||||
if(abs(fac).le.eps) go to 300
|
||||
i = i+1
|
||||
ai = i
|
||||
fac = -fac*alfa/ai
|
||||
f1 = f1+fac
|
||||
if(abs(fac).le.eps) go to 300
|
||||
200 continue
|
||||
300 ress = ab4*(coa*f2+sia*f1)
|
||||
resc = ab4*(coa*f1-sia*f2)
|
||||
400 return
|
||||
end
|
||||
360
cxx/fitpack/fpcurf.f
Normal file
360
cxx/fitpack/fpcurf.f
Normal file
@ -0,0 +1,360 @@
|
||||
recursive subroutine fpcurf(iopt,x,y,w,m,xb,xe,k,s,nest,tol,
|
||||
* maxit,k1,k2,n,t,c,fp,fpint,z,a,b,g,q,nrdata,ier)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 xb,xe,s,tol,fp
|
||||
integer iopt,m,k,nest,maxit,k1,k2,n,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),y(m),w(m),t(nest),c(nest),fpint(nest),
|
||||
* z(nest),a(nest,k1),b(nest,k2),g(nest,k2),q(m,k1)
|
||||
integer nrdata(nest)
|
||||
c ..local scalars..
|
||||
real*8 acc,con1,con4,con9,cos,half,fpart,fpms,fpold,fp0,f1,f2,f3,
|
||||
* one,p,pinv,piv,p1,p2,p3,rn,sin,store,term,wi,xi,yi
|
||||
integer i,ich1,ich3,it,iter,i1,i2,i3,j,k3,l,l0,
|
||||
* mk1,new,nk1,nmax,nmin,nplus,npl1,nrint,n8
|
||||
c ..local arrays..
|
||||
real*8 h(7)
|
||||
c ..function references
|
||||
real*8 abs,fprati
|
||||
integer max0,min0
|
||||
c ..subroutine references..
|
||||
c fpback,fpbspl,fpgivs,fpdisc,fpknot,fprota
|
||||
c ..
|
||||
c set constants
|
||||
one = 0.1d+01
|
||||
con1 = 0.1d0
|
||||
con9 = 0.9d0
|
||||
con4 = 0.4d-01
|
||||
half = 0.5d0
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 1: determination of the number of knots and their position c
|
||||
c ************************************************************** c
|
||||
c given a set of knots we compute the least-squares spline sinf(x), c
|
||||
c and the corresponding sum of squared residuals fp=f(p=inf). c
|
||||
c if iopt=-1 sinf(x) is the requested approximation. c
|
||||
c if iopt=0 or iopt=1 we check whether we can accept the knots: c
|
||||
c if fp <=s we will continue with the current set of knots. c
|
||||
c if fp > s we will increase the number of knots and compute the c
|
||||
c corresponding least-squares spline until finally fp<=s. c
|
||||
c the initial choice of knots depends on the value of s and iopt. c
|
||||
c if s=0 we have spline interpolation; in that case the number of c
|
||||
c knots equals nmax = m+k+1. c
|
||||
c if s > 0 and c
|
||||
c iopt=0 we first compute the least-squares polynomial of c
|
||||
c degree k; n = nmin = 2*k+2 c
|
||||
c iopt=1 we start with the set of knots found at the last c
|
||||
c call of the routine, except for the case that s > fp0; then c
|
||||
c we compute directly the least-squares polynomial of degree k. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c determine nmin, the number of knots for polynomial approximation.
|
||||
nmin = 2*k1
|
||||
if(iopt.lt.0) go to 60
|
||||
c calculation of acc, the absolute tolerance for the root of f(p)=s.
|
||||
acc = tol*s
|
||||
c determine nmax, the number of knots for spline interpolation.
|
||||
nmax = m+k1
|
||||
if(s.gt.0.0d0) go to 45
|
||||
c if s=0, s(x) is an interpolating spline.
|
||||
c test whether the required storage space exceeds the available one.
|
||||
n = nmax
|
||||
if(nmax.gt.nest) go to 420
|
||||
c find the position of the interior knots in case of interpolation.
|
||||
10 mk1 = m-k1
|
||||
if(mk1.eq.0) go to 60
|
||||
k3 = k/2
|
||||
i = k2
|
||||
j = k3+2
|
||||
if(k3*2.eq.k) go to 30
|
||||
do 20 l=1,mk1
|
||||
t(i) = x(j)
|
||||
i = i+1
|
||||
j = j+1
|
||||
20 continue
|
||||
go to 60
|
||||
30 do 40 l=1,mk1
|
||||
t(i) = (x(j)+x(j-1))*half
|
||||
i = i+1
|
||||
j = j+1
|
||||
40 continue
|
||||
go to 60
|
||||
c if s>0 our initial choice of knots depends on the value of iopt.
|
||||
c if iopt=0 or iopt=1 and s>=fp0, we start computing the least-squares
|
||||
c polynomial of degree k which is a spline without interior knots.
|
||||
c if iopt=1 and fp0>s we start computing the least squares spline
|
||||
c according to the set of knots found at the last call of the routine.
|
||||
45 if(iopt.eq.0) go to 50
|
||||
if(n.eq.nmin) go to 50
|
||||
fp0 = fpint(n)
|
||||
fpold = fpint(n-1)
|
||||
nplus = nrdata(n)
|
||||
if(fp0.gt.s) go to 60
|
||||
50 n = nmin
|
||||
fpold = 0.0d0
|
||||
nplus = 0
|
||||
nrdata(1) = m-2
|
||||
c main loop for the different sets of knots. m is a save upper bound
|
||||
c for the number of trials.
|
||||
60 do 200 iter = 1,m
|
||||
if(n.eq.nmin) ier = -2
|
||||
c find nrint, tne number of knot intervals.
|
||||
nrint = n-nmin+1
|
||||
c find the position of the additional knots which are needed for
|
||||
c the b-spline representation of s(x).
|
||||
nk1 = n-k1
|
||||
i = n
|
||||
do 70 j=1,k1
|
||||
t(j) = xb
|
||||
t(i) = xe
|
||||
i = i-1
|
||||
70 continue
|
||||
c compute the b-spline coefficients of the least-squares spline
|
||||
c sinf(x). the observation matrix a is built up row by row and
|
||||
c reduced to upper triangular form by givens transformations.
|
||||
c at the same time fp=f(p=inf) is computed.
|
||||
fp = 0.0d0
|
||||
c initialize the observation matrix a.
|
||||
do 80 i=1,nk1
|
||||
z(i) = 0.0d0
|
||||
do 80 j=1,k1
|
||||
a(i,j) = 0.0d0
|
||||
80 continue
|
||||
l = k1
|
||||
do 130 it=1,m
|
||||
c fetch the current data point x(it),y(it).
|
||||
xi = x(it)
|
||||
wi = w(it)
|
||||
yi = y(it)*wi
|
||||
c search for knot interval t(l) <= xi < t(l+1).
|
||||
85 if(xi.lt.t(l+1) .or. l.eq.nk1) go to 90
|
||||
l = l+1
|
||||
go to 85
|
||||
c evaluate the (k+1) non-zero b-splines at xi and store them in q.
|
||||
90 call fpbspl(t,n,k,xi,l,h)
|
||||
do 95 i=1,k1
|
||||
q(it,i) = h(i)
|
||||
h(i) = h(i)*wi
|
||||
95 continue
|
||||
c rotate the new row of the observation matrix into triangle.
|
||||
j = l-k1
|
||||
do 110 i=1,k1
|
||||
j = j+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.0d0) go to 110
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a(j,1),cos,sin)
|
||||
c transformations to right hand side.
|
||||
call fprota(cos,sin,yi,z(j))
|
||||
if(i.eq.k1) go to 120
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 100 i1 = i3,k1
|
||||
i2 = i2+1
|
||||
c transformations to left hand side.
|
||||
call fprota(cos,sin,h(i1),a(j,i2))
|
||||
100 continue
|
||||
110 continue
|
||||
c add contribution of this row to the sum of squares of residual
|
||||
c right hand sides.
|
||||
120 fp = fp+yi*yi
|
||||
130 continue
|
||||
if(ier.eq.(-2)) fp0 = fp
|
||||
fpint(n) = fp0
|
||||
fpint(n-1) = fpold
|
||||
nrdata(n) = nplus
|
||||
c backward substitution to obtain the b-spline coefficients.
|
||||
call fpback(a,z,nk1,k1,c,nest)
|
||||
c test whether the approximation sinf(x) is an acceptable solution.
|
||||
if(iopt.lt.0) go to 440
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 440
|
||||
c if f(p=inf) < s accept the choice of knots.
|
||||
if(fpms.lt.0.0d0) go to 250
|
||||
c if n = nmax, sinf(x) is an interpolating spline.
|
||||
if(n.eq.nmax) go to 430
|
||||
c increase the number of knots.
|
||||
c if n=nest we cannot increase the number of knots because of
|
||||
c the storage capacity limitation.
|
||||
if(n.eq.nest) go to 420
|
||||
c determine the number of knots nplus we are going to add.
|
||||
if(ier.eq.0) go to 140
|
||||
nplus = 1
|
||||
ier = 0
|
||||
go to 150
|
||||
140 npl1 = nplus*2
|
||||
rn = nplus
|
||||
if(fpold-fp.gt.acc) npl1 = rn*fpms/(fpold-fp)
|
||||
nplus = min0(nplus*2,max0(npl1,nplus/2,1))
|
||||
150 fpold = fp
|
||||
c compute the sum((w(i)*(y(i)-s(x(i))))**2) for each knot interval
|
||||
c t(j+k) <= x(i) <= t(j+k+1) and store it in fpint(j),j=1,2,...nrint.
|
||||
fpart = 0.0d0
|
||||
i = 1
|
||||
l = k2
|
||||
new = 0
|
||||
do 180 it=1,m
|
||||
if(x(it).lt.t(l) .or. l.gt.nk1) go to 160
|
||||
new = 1
|
||||
l = l+1
|
||||
160 term = 0.0d0
|
||||
l0 = l-k2
|
||||
do 170 j=1,k1
|
||||
l0 = l0+1
|
||||
term = term+c(l0)*q(it,j)
|
||||
170 continue
|
||||
term = (w(it)*(term-y(it)))**2
|
||||
fpart = fpart+term
|
||||
if(new.eq.0) go to 180
|
||||
store = term*half
|
||||
fpint(i) = fpart-store
|
||||
i = i+1
|
||||
fpart = store
|
||||
new = 0
|
||||
180 continue
|
||||
fpint(nrint) = fpart
|
||||
do 190 l=1,nplus
|
||||
c add a new knot.
|
||||
call fpknot(x,m,t,n,fpint,nrdata,nrint,nest,1)
|
||||
c if n=nmax we locate the knots as for interpolation.
|
||||
if(n.eq.nmax) go to 10
|
||||
c test whether we cannot further increase the number of knots.
|
||||
if(n.eq.nest) go to 200
|
||||
190 continue
|
||||
c restart the computations with the new set of knots.
|
||||
200 continue
|
||||
c test whether the least-squares kth degree polynomial is a solution
|
||||
c of our approximation problem.
|
||||
250 if(ier.eq.(-2)) go to 440
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 2: determination of the smoothing spline sp(x). c
|
||||
c *************************************************** c
|
||||
c we have determined the number of knots and their position. c
|
||||
c we now compute the b-spline coefficients of the smoothing spline c
|
||||
c sp(x). the observation matrix a is extended by the rows of matrix c
|
||||
c b expressing that the kth derivative discontinuities of sp(x) at c
|
||||
c the interior knots t(k+2),...t(n-k-1) must be zero. the corres- c
|
||||
c ponding weights of these additional rows are set to 1/p. c
|
||||
c iteratively we then have to determine the value of p such that c
|
||||
c f(p)=sum((w(i)*(y(i)-sp(x(i))))**2) be = s. we already know that c
|
||||
c the least-squares kth degree polynomial corresponds to p=0, and c
|
||||
c that the least-squares spline corresponds to p=infinity. the c
|
||||
c iteration process which is proposed here, makes use of rational c
|
||||
c interpolation. since f(p) is a convex and strictly decreasing c
|
||||
c function of p, it can be approximated by a rational function c
|
||||
c r(p) = (u*p+v)/(p+w). three values of p(p1,p2,p3) with correspond- c
|
||||
c ing values of f(p) (f1=f(p1)-s,f2=f(p2)-s,f3=f(p3)-s) are used c
|
||||
c to calculate the new value of p such that r(p)=s. convergence is c
|
||||
c guaranteed by taking f1>0 and f3<0. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c evaluate the discontinuity jump of the kth derivative of the
|
||||
c b-splines at the knots t(l),l=k+2,...n-k-1 and store in b.
|
||||
call fpdisc(t,n,k2,b,nest)
|
||||
c initial value for p.
|
||||
p1 = 0.0d0
|
||||
f1 = fp0-s
|
||||
p3 = -one
|
||||
f3 = fpms
|
||||
p = 0.
|
||||
do 255 i=1,nk1
|
||||
p = p+a(i,1)
|
||||
255 continue
|
||||
rn = nk1
|
||||
p = rn/p
|
||||
ich1 = 0
|
||||
ich3 = 0
|
||||
n8 = n-nmin
|
||||
c iteration process to find the root of f(p) = s.
|
||||
do 360 iter=1,maxit
|
||||
c the rows of matrix b with weight 1/p are rotated into the
|
||||
c triangularised observation matrix a which is stored in g.
|
||||
pinv = one/p
|
||||
do 260 i=1,nk1
|
||||
c(i) = z(i)
|
||||
g(i,k2) = 0.0d0
|
||||
do 260 j=1,k1
|
||||
g(i,j) = a(i,j)
|
||||
260 continue
|
||||
do 300 it=1,n8
|
||||
c the row of matrix b is rotated into triangle by givens transformation
|
||||
do 270 i=1,k2
|
||||
h(i) = b(it,i)*pinv
|
||||
270 continue
|
||||
yi = 0.0d0
|
||||
do 290 j=it,nk1
|
||||
piv = h(1)
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,g(j,1),cos,sin)
|
||||
c transformations to right hand side.
|
||||
call fprota(cos,sin,yi,c(j))
|
||||
if(j.eq.nk1) go to 300
|
||||
i2 = k1
|
||||
if(j.gt.n8) i2 = nk1-j
|
||||
do 280 i=1,i2
|
||||
c transformations to left hand side.
|
||||
i1 = i+1
|
||||
call fprota(cos,sin,h(i1),g(j,i1))
|
||||
h(i) = h(i1)
|
||||
280 continue
|
||||
h(i2+1) = 0.0d0
|
||||
290 continue
|
||||
300 continue
|
||||
c backward substitution to obtain the b-spline coefficients.
|
||||
call fpback(g,c,nk1,k2,c,nest)
|
||||
c computation of f(p).
|
||||
fp = 0.0d0
|
||||
l = k2
|
||||
do 330 it=1,m
|
||||
if(x(it).lt.t(l) .or. l.gt.nk1) go to 310
|
||||
l = l+1
|
||||
310 l0 = l-k2
|
||||
term = 0.0d0
|
||||
do 320 j=1,k1
|
||||
l0 = l0+1
|
||||
term = term+c(l0)*q(it,j)
|
||||
320 continue
|
||||
fp = fp+(w(it)*(term-y(it)))**2
|
||||
330 continue
|
||||
c test whether the approximation sp(x) is an acceptable solution.
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 440
|
||||
c test whether the maximal number of iterations is reached.
|
||||
if(iter.eq.maxit) go to 400
|
||||
c carry out one more step of the iteration process.
|
||||
p2 = p
|
||||
f2 = fpms
|
||||
if(ich3.ne.0) go to 340
|
||||
if((f2-f3).gt.acc) go to 335
|
||||
c our initial choice of p is too large.
|
||||
p3 = p2
|
||||
f3 = f2
|
||||
p = p*con4
|
||||
if(p.le.p1) p=p1*con9 + p2*con1
|
||||
go to 360
|
||||
335 if(f2.lt.0.0d0) ich3=1
|
||||
340 if(ich1.ne.0) go to 350
|
||||
if((f1-f2).gt.acc) go to 345
|
||||
c our initial choice of p is too small
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
p = p/con4
|
||||
if(p3.lt.0.) go to 360
|
||||
if(p.ge.p3) p = p2*con1 + p3*con9
|
||||
go to 360
|
||||
345 if(f2.gt.0.0d0) ich1=1
|
||||
c test whether the iteration process proceeds as theoretically
|
||||
c expected.
|
||||
350 if(f2.ge.f1 .or. f2.le.f3) go to 410
|
||||
c find the new value for p.
|
||||
p = fprati(p1,f1,p2,f2,p3,f3)
|
||||
360 continue
|
||||
c error codes and messages.
|
||||
400 ier = 3
|
||||
go to 440
|
||||
410 ier = 2
|
||||
go to 440
|
||||
420 ier = 1
|
||||
go to 440
|
||||
430 ier = -1
|
||||
440 return
|
||||
end
|
||||
95
cxx/fitpack/fpcuro.f
Normal file
95
cxx/fitpack/fpcuro.f
Normal file
@ -0,0 +1,95 @@
|
||||
recursive subroutine fpcuro(a,b,c,d,x,n)
|
||||
implicit none
|
||||
c subroutine fpcuro finds the real zeros of a cubic polynomial
|
||||
c p(x) = a*x**3+b*x**2+c*x+d.
|
||||
c
|
||||
c calling sequence:
|
||||
c call fpcuro(a,b,c,d,x,n)
|
||||
c
|
||||
c input parameters:
|
||||
c a,b,c,d: real values, containing the coefficients of p(x).
|
||||
c
|
||||
c output parameters:
|
||||
c x : real array,length 3, which contains the real zeros of p(x)
|
||||
c n : integer, giving the number of real zeros of p(x).
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 a,b,c,d
|
||||
integer n
|
||||
c ..array argument..
|
||||
real*8 x(3)
|
||||
c ..local scalars..
|
||||
integer i
|
||||
real*8 a1,b1,c1,df,disc,d1,e3,f,four,half,ovfl,pi3,p3,q,r,
|
||||
* step,tent,three,two,u,u1,u2,y
|
||||
c ..function references..
|
||||
real*8 abs,max,datan,atan2,cos,sign,sqrt
|
||||
c set constants
|
||||
two = 0.2d+01
|
||||
three = 0.3d+01
|
||||
four = 0.4d+01
|
||||
ovfl =0.1d+05
|
||||
half = 0.5d+0
|
||||
tent = 0.1d+0
|
||||
e3 = tent/0.3d0
|
||||
pi3 = datan(0.1d+01)/0.75d0
|
||||
a1 = abs(a)
|
||||
b1 = abs(b)
|
||||
c1 = abs(c)
|
||||
d1 = abs(d)
|
||||
c test whether p(x) is a third degree polynomial.
|
||||
if(max(b1,c1,d1).lt.a1*ovfl) go to 300
|
||||
c test whether p(x) is a second degree polynomial.
|
||||
if(max(c1,d1).lt.b1*ovfl) go to 200
|
||||
c test whether p(x) is a first degree polynomial.
|
||||
if(d1.lt.c1*ovfl) go to 100
|
||||
c p(x) is a constant function.
|
||||
n = 0
|
||||
go to 800
|
||||
c p(x) is a first degree polynomial.
|
||||
100 n = 1
|
||||
x(1) = -d/c
|
||||
go to 500
|
||||
c p(x) is a second degree polynomial.
|
||||
200 disc = c*c-four*b*d
|
||||
n = 0
|
||||
if(disc.lt.0.) go to 800
|
||||
n = 2
|
||||
u = sqrt(disc)
|
||||
b1 = b+b
|
||||
x(1) = (-c+u)/b1
|
||||
x(2) = (-c-u)/b1
|
||||
go to 500
|
||||
c p(x) is a third degree polynomial.
|
||||
300 b1 = b/a*e3
|
||||
c1 = c/a
|
||||
d1 = d/a
|
||||
q = c1*e3-b1*b1
|
||||
r = b1*b1*b1+(d1-b1*c1)*half
|
||||
disc = q*q*q+r*r
|
||||
if(disc.gt.0.) go to 400
|
||||
u = sqrt(abs(q))
|
||||
if(r.lt.0.) u = -u
|
||||
p3 = atan2(sqrt(-disc),abs(r))*e3
|
||||
u2 = u+u
|
||||
n = 3
|
||||
x(1) = -u2*cos(p3)-b1
|
||||
x(2) = u2*cos(pi3-p3)-b1
|
||||
x(3) = u2*cos(pi3+p3)-b1
|
||||
go to 500
|
||||
400 u = sqrt(disc)
|
||||
u1 = -r+u
|
||||
u2 = -r-u
|
||||
n = 1
|
||||
x(1) = sign(abs(u1)**e3,u1)+sign(abs(u2)**e3,u2)-b1
|
||||
c apply a newton iteration to improve the accuracy of the roots.
|
||||
500 do 700 i=1,n
|
||||
y = x(i)
|
||||
f = ((a*y+b)*y+c)*y+d
|
||||
df = (three*a*y+two*b)*y+c
|
||||
step = 0.
|
||||
if(abs(f).lt.abs(df)*tent) step = f/df
|
||||
x(i) = y-step
|
||||
700 continue
|
||||
800 return
|
||||
end
|
||||
54
cxx/fitpack/fpcyt1.f
Normal file
54
cxx/fitpack/fpcyt1.f
Normal file
@ -0,0 +1,54 @@
|
||||
recursive subroutine fpcyt1(a,n,nn)
|
||||
implicit none
|
||||
c (l u)-decomposition of a cyclic tridiagonal matrix with the non-zero
|
||||
c elements stored as follows
|
||||
c
|
||||
c | a(1,2) a(1,3) a(1,1) |
|
||||
c | a(2,1) a(2,2) a(2,3) |
|
||||
c | a(3,1) a(3,2) a(3,3) |
|
||||
c | ............... |
|
||||
c | a(n-1,1) a(n-1,2) a(n-1,3) |
|
||||
c | a(n,3) a(n,1) a(n,2) |
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer n,nn
|
||||
c ..array arguments..
|
||||
real*8 a(nn,6)
|
||||
c ..local scalars..
|
||||
real*8 aa,beta,gamma,sum,teta,v,one
|
||||
integer i,n1,n2
|
||||
c ..
|
||||
c set constant
|
||||
one = 1
|
||||
n2 = n-2
|
||||
beta = one/a(1,2)
|
||||
gamma = a(n,3)
|
||||
teta = a(1,1)*beta
|
||||
a(1,4) = beta
|
||||
a(1,5) = gamma
|
||||
a(1,6) = teta
|
||||
sum = gamma*teta
|
||||
do 10 i=2,n2
|
||||
v = a(i-1,3)*beta
|
||||
aa = a(i,1)
|
||||
beta = one/(a(i,2)-aa*v)
|
||||
gamma = -gamma*v
|
||||
teta = -teta*aa*beta
|
||||
a(i,4) = beta
|
||||
a(i,5) = gamma
|
||||
a(i,6) = teta
|
||||
sum = sum+gamma*teta
|
||||
10 continue
|
||||
n1 = n-1
|
||||
v = a(n2,3)*beta
|
||||
aa = a(n1,1)
|
||||
beta = one/(a(n1,2)-aa*v)
|
||||
gamma = a(n,1)-gamma*v
|
||||
teta = (a(n1,3)-teta*aa)*beta
|
||||
a(n1,4) = beta
|
||||
a(n1,5) = gamma
|
||||
a(n1,6) = teta
|
||||
a(n,4) = one/(a(n,2)-(sum+gamma*teta))
|
||||
return
|
||||
end
|
||||
33
cxx/fitpack/fpcyt2.f
Normal file
33
cxx/fitpack/fpcyt2.f
Normal file
@ -0,0 +1,33 @@
|
||||
recursive subroutine fpcyt2(a,n,b,c,nn)
|
||||
implicit none
|
||||
c subroutine fpcyt2 solves a linear n x n system
|
||||
c a * c = b
|
||||
c where matrix a is a cyclic tridiagonal matrix, decomposed
|
||||
c using subroutine fpsyt1.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer n,nn
|
||||
c ..array arguments..
|
||||
real*8 a(nn,6),b(n),c(n)
|
||||
c ..local scalars..
|
||||
real*8 cc,sum
|
||||
integer i,j,j1,n1
|
||||
c ..
|
||||
c(1) = b(1)*a(1,4)
|
||||
sum = c(1)*a(1,5)
|
||||
n1 = n-1
|
||||
do 10 i=2,n1
|
||||
c(i) = (b(i)-a(i,1)*c(i-1))*a(i,4)
|
||||
sum = sum+c(i)*a(i,5)
|
||||
10 continue
|
||||
cc = (b(n)-sum)*a(n,4)
|
||||
c(n) = cc
|
||||
c(n1) = c(n1)-cc*a(n1,6)
|
||||
j = n1
|
||||
do 20 i=3,n
|
||||
j1 = j-1
|
||||
c(j1) = c(j1)-c(j)*a(j1,3)*a(j1,4)-cc*a(j1,6)
|
||||
j = j1
|
||||
20 continue
|
||||
return
|
||||
end
|
||||
56
cxx/fitpack/fpdeno.f
Normal file
56
cxx/fitpack/fpdeno.f
Normal file
@ -0,0 +1,56 @@
|
||||
recursive subroutine fpdeno(maxtr,up,left,right,nbind,merk)
|
||||
implicit none
|
||||
c subroutine fpdeno frees the nodes of all branches of a triply linked
|
||||
c tree with length < nbind by putting to zero their up field.
|
||||
c on exit the parameter merk points to the terminal node of the
|
||||
c most left branch of length nbind or takes the value 1 if there
|
||||
c is no such branch.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer maxtr,nbind,merk
|
||||
c ..array arguments..
|
||||
integer up(maxtr),left(maxtr),right(maxtr)
|
||||
c ..local scalars ..
|
||||
integer i,j,k,l,niveau,point
|
||||
c ..
|
||||
i = 1
|
||||
niveau = 0
|
||||
10 point = i
|
||||
i = left(point)
|
||||
if(i.eq.0) go to 20
|
||||
niveau = niveau+1
|
||||
go to 10
|
||||
20 if(niveau.eq.nbind) go to 70
|
||||
30 i = right(point)
|
||||
j = up(point)
|
||||
up(point) = 0
|
||||
k = left(j)
|
||||
if(point.ne.k) go to 50
|
||||
if(i.ne.0) go to 40
|
||||
niveau = niveau-1
|
||||
if(niveau.eq.0) go to 80
|
||||
point = j
|
||||
go to 30
|
||||
40 left(j) = i
|
||||
go to 10
|
||||
50 l = right(k)
|
||||
if(point.eq.l) go to 60
|
||||
k = l
|
||||
go to 50
|
||||
60 right(k) = i
|
||||
point = k
|
||||
70 i = right(point)
|
||||
if(i.ne.0) go to 10
|
||||
i = up(point)
|
||||
niveau = niveau-1
|
||||
if(niveau.eq.0) go to 80
|
||||
point = i
|
||||
go to 70
|
||||
80 k = 1
|
||||
l = left(k)
|
||||
if(up(l).eq.0) return
|
||||
90 merk = k
|
||||
k = left(k)
|
||||
if(k.ne.0) go to 90
|
||||
return
|
||||
end
|
||||
44
cxx/fitpack/fpdisc.f
Normal file
44
cxx/fitpack/fpdisc.f
Normal file
@ -0,0 +1,44 @@
|
||||
recursive subroutine fpdisc(t,n,k2,b,nest)
|
||||
implicit none
|
||||
c subroutine fpdisc calculates the discontinuity jumps of the kth
|
||||
c derivative of the b-splines of degree k at the knots t(k+2)..t(n-k-1)
|
||||
c ..scalar arguments..
|
||||
integer n,k2,nest
|
||||
c ..array arguments..
|
||||
real*8 t(n),b(nest,k2)
|
||||
c ..local scalars..
|
||||
real*8 an,fac,prod
|
||||
integer i,ik,j,jk,k,k1,l,lj,lk,lmk,lp,nk1,nrint
|
||||
c ..local array..
|
||||
real*8 h(12)
|
||||
c ..
|
||||
k1 = k2-1
|
||||
k = k1-1
|
||||
nk1 = n-k1
|
||||
nrint = nk1-k
|
||||
an = nrint
|
||||
fac = an/(t(nk1+1)-t(k1))
|
||||
do 40 l=k2,nk1
|
||||
lmk = l-k1
|
||||
do 10 j=1,k1
|
||||
ik = j+k1
|
||||
lj = l+j
|
||||
lk = lj-k2
|
||||
h(j) = t(l)-t(lk)
|
||||
h(ik) = t(l)-t(lj)
|
||||
10 continue
|
||||
lp = lmk
|
||||
do 30 j=1,k2
|
||||
jk = j
|
||||
prod = h(j)
|
||||
do 20 i=1,k
|
||||
jk = jk+1
|
||||
prod = prod*h(jk)*fac
|
||||
20 continue
|
||||
lk = lp+k1
|
||||
b(lmk,j) = (t(lk)-t(lp))/prod
|
||||
lp = lp+1
|
||||
30 continue
|
||||
40 continue
|
||||
return
|
||||
end
|
||||
70
cxx/fitpack/fpfrno.f
Normal file
70
cxx/fitpack/fpfrno.f
Normal file
@ -0,0 +1,70 @@
|
||||
recursive subroutine fpfrno(maxtr,up,left,right,info,point,
|
||||
* merk,n1,count,ier)
|
||||
implicit none
|
||||
c subroutine fpfrno collects the free nodes (up field zero) of the
|
||||
c triply linked tree the information of which is kept in the arrays
|
||||
c up,left,right and info. the maximal length of the branches of the
|
||||
c tree is given by n1. if no free nodes are found, the error flag
|
||||
c ier is set to 1.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer maxtr,point,merk,n1,count,ier
|
||||
c ..array arguments..
|
||||
integer up(maxtr),left(maxtr),right(maxtr),info(maxtr)
|
||||
c ..local scalars
|
||||
integer i,j,k,l,n,niveau
|
||||
c ..
|
||||
ier = 1
|
||||
if(n1.eq.2) go to 140
|
||||
niveau = 1
|
||||
count = 2
|
||||
10 j = 0
|
||||
i = 1
|
||||
20 if(j.eq.niveau) go to 30
|
||||
k = 0
|
||||
l = left(i)
|
||||
if(l.eq.0) go to 110
|
||||
i = l
|
||||
j = j+1
|
||||
go to 20
|
||||
30 if (i.lt.count) go to 110
|
||||
if (i.eq.count) go to 100
|
||||
go to 40
|
||||
40 if(up(count).eq.0) go to 50
|
||||
count = count+1
|
||||
go to 30
|
||||
50 up(count) = up(i)
|
||||
left(count) = left(i)
|
||||
right(count) = right(i)
|
||||
info(count) = info(i)
|
||||
if(merk.eq.i) merk = count
|
||||
if(point.eq.i) point = count
|
||||
if(k.eq.0) go to 60
|
||||
right(k) = count
|
||||
go to 70
|
||||
60 n = up(i)
|
||||
left(n) = count
|
||||
70 l = left(i)
|
||||
80 if(l.eq.0) go to 90
|
||||
up(l) = count
|
||||
l = right(l)
|
||||
go to 80
|
||||
90 up(i) = 0
|
||||
i = count
|
||||
100 count = count+1
|
||||
110 l = right(i)
|
||||
k = i
|
||||
if(l.eq.0) go to 120
|
||||
i = l
|
||||
go to 20
|
||||
120 l = up(i)
|
||||
j = j-1
|
||||
if(j.eq.0) go to 130
|
||||
i = l
|
||||
go to 110
|
||||
130 niveau = niveau+1
|
||||
if(niveau.le.n1) go to 10
|
||||
if(count.gt.maxtr) go to 140
|
||||
ier = 0
|
||||
140 return
|
||||
end
|
||||
21
cxx/fitpack/fpgivs.f
Normal file
21
cxx/fitpack/fpgivs.f
Normal file
@ -0,0 +1,21 @@
|
||||
recursive subroutine fpgivs(piv,ww,cos,sin)
|
||||
implicit none
|
||||
c subroutine fpgivs calculates the parameters of a givens
|
||||
c transformation .
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 piv,ww,cos,sin
|
||||
c ..local scalars..
|
||||
real*8 dd,one,store
|
||||
c ..function references..
|
||||
real*8 abs,sqrt
|
||||
c ..
|
||||
one = 0.1e+01
|
||||
store = abs(piv)
|
||||
if(store.ge.ww) dd = store*sqrt(one+(ww/piv)**2)
|
||||
if(store.lt.ww) dd = ww*sqrt(one+(piv/ww)**2)
|
||||
cos = ww/dd
|
||||
sin = piv/dd
|
||||
ww = dd
|
||||
return
|
||||
end
|
||||
601
cxx/fitpack/fpgrdi.f
Normal file
601
cxx/fitpack/fpgrdi.f
Normal file
@ -0,0 +1,601 @@
|
||||
recursive subroutine fpgrdi(ifsu,ifsv,ifbu,ifbv,iback,u,mu,v,
|
||||
* mv,z,mz,dz,iop0,iop1,tu,nu,tv,nv,p,c,nc,sq,fp,fpu,fpv,mm,
|
||||
* mvnu,spu,spv,right,q,au,av1,av2,bu,bv,aa,bb,cc,cosi,nru,nrv)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 p,sq,fp
|
||||
integer ifsu,ifsv,ifbu,ifbv,iback,mu,mv,mz,iop0,iop1,nu,nv,nc,
|
||||
* mm,mvnu
|
||||
c ..array arguments..
|
||||
real*8 u(mu),v(mv),z(mz),dz(3),tu(nu),tv(nv),c(nc),fpu(nu),fpv(nv)
|
||||
*,
|
||||
* spu(mu,4),spv(mv,4),right(mm),q(mvnu),au(nu,5),av1(nv,6),
|
||||
* av2(nv,4),aa(2,mv),bb(2,nv),cc(nv),cosi(2,nv),bu(nu,5),bv(nv,5)
|
||||
integer nru(mu),nrv(mv)
|
||||
c ..local scalars..
|
||||
real*8 arg,co,dz1,dz2,dz3,fac,fac0,pinv,piv,si,term,one,three,half
|
||||
*
|
||||
integer i,ic,ii,ij,ik,iq,irot,it,iz,i0,i1,i2,i3,j,jj,jk,jper,
|
||||
* j0,j1,k,k1,k2,l,l0,l1,l2,mvv,ncof,nrold,nroldu,nroldv,number,
|
||||
* numu,numu1,numv,numv1,nuu,nu4,nu7,nu8,nu9,nv11,nv4,nv7,nv8,n1
|
||||
c ..local arrays..
|
||||
real*8 h(5),h1(5),h2(4)
|
||||
c ..function references..
|
||||
integer min0
|
||||
real*8 cos,sin
|
||||
c ..subroutine references..
|
||||
c fpback,fpbspl,fpgivs,fpcyt1,fpcyt2,fpdisc,fpbacp,fprota
|
||||
c ..
|
||||
c let
|
||||
c | (spu) | | (spv) |
|
||||
c (au) = | ---------- | (av) = | ---------- |
|
||||
c | (1/p) (bu) | | (1/p) (bv) |
|
||||
c
|
||||
c | z ' 0 |
|
||||
c q = | ------ |
|
||||
c | 0 ' 0 |
|
||||
c
|
||||
c with c : the (nu-4) x (nv-4) matrix which contains the b-spline
|
||||
c coefficients.
|
||||
c z : the mu x mv matrix which contains the function values.
|
||||
c spu,spv: the mu x (nu-4), resp. mv x (nv-4) observation matrices
|
||||
c according to the least-squares problems in the u-,resp.
|
||||
c v-direction.
|
||||
c bu,bv : the (nu-7) x (nu-4),resp. (nv-7) x (nv-4) matrices
|
||||
c containing the discontinuity jumps of the derivatives
|
||||
c of the b-splines in the u-,resp.v-variable at the knots
|
||||
c the b-spline coefficients of the smoothing spline are then calculated
|
||||
c as the least-squares solution of the following over-determined linear
|
||||
c system of equations
|
||||
c
|
||||
c (1) (av) c (au)' = q
|
||||
c
|
||||
c subject to the constraints
|
||||
c
|
||||
c (2) c(i,nv-3+j) = c(i,j), j=1,2,3 ; i=1,2,...,nu-4
|
||||
c
|
||||
c (3) if iop0 = 0 c(1,j) = dz(1)
|
||||
c iop0 = 1 c(1,j) = dz(1)
|
||||
c c(2,j) = dz(1)+(dz(2)*cosi(1,j)+dz(3)*cosi(2,j))*
|
||||
c tu(5)/3. = cc(j) , j=1,2,...nv-4
|
||||
c
|
||||
c (4) if iop1 = 1 c(nu-4,j) = 0, j=1,2,...,nv-4.
|
||||
c
|
||||
c set constants
|
||||
one = 1
|
||||
three = 3
|
||||
half = 0.5
|
||||
c initialization
|
||||
nu4 = nu-4
|
||||
nu7 = nu-7
|
||||
nu8 = nu-8
|
||||
nu9 = nu-9
|
||||
nv4 = nv-4
|
||||
nv7 = nv-7
|
||||
nv8 = nv-8
|
||||
nv11 = nv-11
|
||||
nuu = nu4-iop0-iop1-1
|
||||
if(p.gt.0.) pinv = one/p
|
||||
c it depends on the value of the flags ifsu,ifsv,ifbu,ifbv and iop0 and
|
||||
c on the value of p whether the matrices (spu), (spv), (bu), (bv) and
|
||||
c (cosi) still must be determined.
|
||||
if(ifsu.ne.0) go to 30
|
||||
c calculate the non-zero elements of the matrix (spu) which is the ob-
|
||||
c servation matrix according to the least-squares spline approximation
|
||||
c problem in the u-direction.
|
||||
l = 4
|
||||
l1 = 5
|
||||
number = 0
|
||||
do 25 it=1,mu
|
||||
arg = u(it)
|
||||
10 if(arg.lt.tu(l1) .or. l.eq.nu4) go to 15
|
||||
l = l1
|
||||
l1 = l+1
|
||||
number = number+1
|
||||
go to 10
|
||||
15 call fpbspl(tu,nu,3,arg,l,h)
|
||||
do 20 i=1,4
|
||||
spu(it,i) = h(i)
|
||||
20 continue
|
||||
nru(it) = number
|
||||
25 continue
|
||||
ifsu = 1
|
||||
c calculate the non-zero elements of the matrix (spv) which is the ob-
|
||||
c servation matrix according to the least-squares spline approximation
|
||||
c problem in the v-direction.
|
||||
30 if(ifsv.ne.0) go to 85
|
||||
l = 4
|
||||
l1 = 5
|
||||
number = 0
|
||||
do 50 it=1,mv
|
||||
arg = v(it)
|
||||
35 if(arg.lt.tv(l1) .or. l.eq.nv4) go to 40
|
||||
l = l1
|
||||
l1 = l+1
|
||||
number = number+1
|
||||
go to 35
|
||||
40 call fpbspl(tv,nv,3,arg,l,h)
|
||||
do 45 i=1,4
|
||||
spv(it,i) = h(i)
|
||||
45 continue
|
||||
nrv(it) = number
|
||||
50 continue
|
||||
ifsv = 1
|
||||
if(iop0.eq.0) go to 85
|
||||
c calculate the coefficients of the interpolating splines for cos(v)
|
||||
c and sin(v).
|
||||
do 55 i=1,nv4
|
||||
cosi(1,i) = 0.
|
||||
cosi(2,i) = 0.
|
||||
55 continue
|
||||
if(nv7.lt.4) go to 85
|
||||
do 65 i=1,nv7
|
||||
l = i+3
|
||||
arg = tv(l)
|
||||
call fpbspl(tv,nv,3,arg,l,h)
|
||||
do 60 j=1,3
|
||||
av1(i,j) = h(j)
|
||||
60 continue
|
||||
cosi(1,i) = cos(arg)
|
||||
cosi(2,i) = sin(arg)
|
||||
65 continue
|
||||
call fpcyt1(av1,nv7,nv)
|
||||
do 80 j=1,2
|
||||
do 70 i=1,nv7
|
||||
right(i) = cosi(j,i)
|
||||
70 continue
|
||||
call fpcyt2(av1,nv7,right,right,nv)
|
||||
do 75 i=1,nv7
|
||||
cosi(j,i+1) = right(i)
|
||||
75 continue
|
||||
cosi(j,1) = cosi(j,nv7+1)
|
||||
cosi(j,nv7+2) = cosi(j,2)
|
||||
cosi(j,nv4) = cosi(j,3)
|
||||
80 continue
|
||||
85 if(p.le.0.) go to 150
|
||||
c calculate the non-zero elements of the matrix (bu).
|
||||
if(ifbu.ne.0 .or. nu8.eq.0) go to 90
|
||||
call fpdisc(tu,nu,5,bu,nu)
|
||||
ifbu = 1
|
||||
c calculate the non-zero elements of the matrix (bv).
|
||||
90 if(ifbv.ne.0 .or. nv8.eq.0) go to 150
|
||||
call fpdisc(tv,nv,5,bv,nv)
|
||||
ifbv = 1
|
||||
c substituting (2),(3) and (4) into (1), we obtain the overdetermined
|
||||
c system
|
||||
c (5) (avv) (cr) (auu)' = (qq)
|
||||
c from which the nuu*nv7 remaining coefficients
|
||||
c c(i,j) , i=2+iop0,3+iop0,...,nu-4-iop1 ; j=1,2,...,nv-7 ,
|
||||
c the elements of (cr), are then determined in the least-squares sense.
|
||||
c simultaneously, we compute the resulting sum of squared residuals sq.
|
||||
150 dz1 = dz(1)
|
||||
do 155 i=1,mv
|
||||
aa(1,i) = dz1
|
||||
155 continue
|
||||
if(nv8.eq.0 .or. p.le.0.) go to 165
|
||||
do 160 i=1,nv8
|
||||
bb(1,i) = 0.
|
||||
160 continue
|
||||
165 mvv = mv
|
||||
if(iop0.eq.0) go to 220
|
||||
fac = tu(5)/three
|
||||
dz2 = dz(2)*fac
|
||||
dz3 = dz(3)*fac
|
||||
do 170 i=1,nv4
|
||||
cc(i) = dz1+dz2*cosi(1,i)+dz3*cosi(2,i)
|
||||
170 continue
|
||||
do 190 i=1,mv
|
||||
number = nrv(i)
|
||||
fac = 0.
|
||||
do 180 j=1,4
|
||||
number = number+1
|
||||
fac = fac+cc(number)*spv(i,j)
|
||||
180 continue
|
||||
aa(2,i) = fac
|
||||
190 continue
|
||||
if(nv8.eq.0 .or. p.le.0.) go to 220
|
||||
do 210 i=1,nv8
|
||||
number = i
|
||||
fac = 0.
|
||||
do 200 j=1,5
|
||||
fac = fac+cc(number)*bv(i,j)
|
||||
number = number+1
|
||||
200 continue
|
||||
bb(2,i) = fac*pinv
|
||||
210 continue
|
||||
mvv = mvv+nv8
|
||||
c we first determine the matrices (auu) and (qq). then we reduce the
|
||||
c matrix (auu) to upper triangular form (ru) using givens rotations.
|
||||
c we apply the same transformations to the rows of matrix qq to obtain
|
||||
c the (mv+nv8) x nuu matrix g.
|
||||
c we store matrix (ru) into au and g into q.
|
||||
220 l = mvv*nuu
|
||||
c initialization.
|
||||
sq = 0.
|
||||
do 230 i=1,l
|
||||
q(i) = 0.
|
||||
230 continue
|
||||
do 240 i=1,nuu
|
||||
do 240 j=1,5
|
||||
au(i,j) = 0.
|
||||
240 continue
|
||||
l = 0
|
||||
nrold = 0
|
||||
n1 = nrold+1
|
||||
do 420 it=1,mu
|
||||
number = nru(it)
|
||||
c find the appropriate column of q.
|
||||
250 do 260 j=1,mvv
|
||||
right(j) = 0.
|
||||
260 continue
|
||||
if(nrold.eq.number) go to 280
|
||||
if(p.le.0.) go to 410
|
||||
c fetch a new row of matrix (bu).
|
||||
do 270 j=1,5
|
||||
h(j) = bu(n1,j)*pinv
|
||||
270 continue
|
||||
i0 = 1
|
||||
i1 = 5
|
||||
go to 310
|
||||
c fetch a new row of matrix (spu).
|
||||
280 do 290 j=1,4
|
||||
h(j) = spu(it,j)
|
||||
290 continue
|
||||
c find the appropriate column of q.
|
||||
do 300 j=1,mv
|
||||
l = l+1
|
||||
right(j) = z(l)
|
||||
300 continue
|
||||
i0 = 1
|
||||
i1 = 4
|
||||
310 if(nu7-number .eq. iop1) i1 = i1-1
|
||||
j0 = n1
|
||||
c take into account that we eliminate the constraints (3)
|
||||
320 if(j0-1.gt.iop0) go to 360
|
||||
fac0 = h(i0)
|
||||
do 330 j=1,mv
|
||||
right(j) = right(j)-fac0*aa(j0,j)
|
||||
330 continue
|
||||
if(mv.eq.mvv) go to 350
|
||||
j = mv
|
||||
do 340 jj=1,nv8
|
||||
j = j+1
|
||||
right(j) = right(j)-fac0*bb(j0,jj)
|
||||
340 continue
|
||||
350 j0 = j0+1
|
||||
i0 = i0+1
|
||||
go to 320
|
||||
360 irot = nrold-iop0-1
|
||||
if(irot.lt.0) irot = 0
|
||||
c rotate the new row of matrix (auu) into triangle.
|
||||
do 390 i=i0,i1
|
||||
irot = irot+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 390
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,au(irot,1),co,si)
|
||||
c apply that transformation to the rows of matrix (qq).
|
||||
iq = (irot-1)*mvv
|
||||
do 370 j=1,mvv
|
||||
iq = iq+1
|
||||
call fprota(co,si,right(j),q(iq))
|
||||
370 continue
|
||||
c apply that transformation to the columns of (auu).
|
||||
if(i.eq.i1) go to 390
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 380 j=i3,i1
|
||||
i2 = i2+1
|
||||
call fprota(co,si,h(j),au(irot,i2))
|
||||
380 continue
|
||||
390 continue
|
||||
c we update the sum of squared residuals
|
||||
do 395 j=1,mvv
|
||||
sq = sq+right(j)**2
|
||||
395 continue
|
||||
if(nrold.eq.number) go to 420
|
||||
410 nrold = n1
|
||||
n1 = n1+1
|
||||
go to 250
|
||||
420 continue
|
||||
c we determine the matrix (avv) and then we reduce her to
|
||||
c upper triangular form (rv) using givens rotations.
|
||||
c we apply the same transformations to the columns of matrix
|
||||
c g to obtain the (nv-7) x (nu-5-iop0-iop1) matrix h.
|
||||
c we store matrix (rv) into av1 and av2, h into c.
|
||||
c the nv7 x nv7 upper triangular matrix (rv) has the form
|
||||
c | av1 ' |
|
||||
c (rv) = | ' av2 |
|
||||
c | 0 ' |
|
||||
c with (av2) a nv7 x 4 matrix and (av1) a nv11 x nv11 upper
|
||||
c triangular matrix of bandwidth 5.
|
||||
ncof = nuu*nv7
|
||||
c initialization.
|
||||
do 430 i=1,ncof
|
||||
c(i) = 0.
|
||||
430 continue
|
||||
do 440 i=1,nv4
|
||||
av1(i,5) = 0.
|
||||
do 440 j=1,4
|
||||
av1(i,j) = 0.
|
||||
av2(i,j) = 0.
|
||||
440 continue
|
||||
jper = 0
|
||||
nrold = 0
|
||||
do 770 it=1,mv
|
||||
number = nrv(it)
|
||||
450 if(nrold.eq.number) go to 480
|
||||
if(p.le.0.) go to 760
|
||||
c fetch a new row of matrix (bv).
|
||||
n1 = nrold+1
|
||||
do 460 j=1,5
|
||||
h(j) = bv(n1,j)*pinv
|
||||
460 continue
|
||||
c find the appropriate row of g.
|
||||
do 465 j=1,nuu
|
||||
right(j) = 0.
|
||||
465 continue
|
||||
if(mv.eq.mvv) go to 510
|
||||
l = mv+n1
|
||||
do 470 j=1,nuu
|
||||
right(j) = q(l)
|
||||
l = l+mvv
|
||||
470 continue
|
||||
go to 510
|
||||
c fetch a new row of matrix (spv)
|
||||
480 h(5) = 0.
|
||||
do 490 j=1,4
|
||||
h(j) = spv(it,j)
|
||||
490 continue
|
||||
c find the appropriate row of g.
|
||||
l = it
|
||||
do 500 j=1,nuu
|
||||
right(j) = q(l)
|
||||
l = l+mvv
|
||||
500 continue
|
||||
c test whether there are non-zero values in the new row of (avv)
|
||||
c corresponding to the b-splines n(j,v),j=nv7+1,...,nv4.
|
||||
510 if(nrold.lt.nv11) go to 710
|
||||
if(jper.ne.0) go to 550
|
||||
c initialize the matrix (av2).
|
||||
jk = nv11+1
|
||||
do 540 i=1,4
|
||||
ik = jk
|
||||
do 520 j=1,5
|
||||
if(ik.le.0) go to 530
|
||||
av2(ik,i) = av1(ik,j)
|
||||
ik = ik-1
|
||||
520 continue
|
||||
530 jk = jk+1
|
||||
540 continue
|
||||
jper = 1
|
||||
c if one of the non-zero elements of the new row corresponds to one of
|
||||
c the b-splines n(j;v),j=nv7+1,...,nv4, we take account of condition
|
||||
c (2) for setting up this row of (avv). the row is stored in h1( the
|
||||
c part with respect to av1) and h2 (the part with respect to av2).
|
||||
550 do 560 i=1,4
|
||||
h1(i) = 0.
|
||||
h2(i) = 0.
|
||||
560 continue
|
||||
h1(5) = 0.
|
||||
j = nrold-nv11
|
||||
do 600 i=1,5
|
||||
j = j+1
|
||||
l0 = j
|
||||
570 l1 = l0-4
|
||||
if(l1.le.0) go to 590
|
||||
if(l1.le.nv11) go to 580
|
||||
l0 = l1-nv11
|
||||
go to 570
|
||||
580 h1(l1) = h(i)
|
||||
go to 600
|
||||
590 h2(l0) = h2(l0) + h(i)
|
||||
600 continue
|
||||
c rotate the new row of (avv) into triangle.
|
||||
if(nv11.le.0) go to 670
|
||||
c rotations with the rows 1,2,...,nv11 of (avv).
|
||||
do 660 j=1,nv11
|
||||
piv = h1(1)
|
||||
i2 = min0(nv11-j,4)
|
||||
if(piv.eq.0.) go to 640
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,av1(j,1),co,si)
|
||||
c apply that transformation to the columns of matrix g.
|
||||
ic = j
|
||||
do 610 i=1,nuu
|
||||
call fprota(co,si,right(i),c(ic))
|
||||
ic = ic+nv7
|
||||
610 continue
|
||||
c apply that transformation to the rows of (avv) with respect to av2.
|
||||
do 620 i=1,4
|
||||
call fprota(co,si,h2(i),av2(j,i))
|
||||
620 continue
|
||||
c apply that transformation to the rows of (avv) with respect to av1.
|
||||
if(i2.eq.0) go to 670
|
||||
do 630 i=1,i2
|
||||
i1 = i+1
|
||||
call fprota(co,si,h1(i1),av1(j,i1))
|
||||
630 continue
|
||||
640 do 650 i=1,i2
|
||||
h1(i) = h1(i+1)
|
||||
650 continue
|
||||
h1(i2+1) = 0.
|
||||
660 continue
|
||||
c rotations with the rows nv11+1,...,nv7 of avv.
|
||||
670 do 700 j=1,4
|
||||
ij = nv11+j
|
||||
if(ij.le.0) go to 700
|
||||
piv = h2(j)
|
||||
if(piv.eq.0.) go to 700
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,av2(ij,j),co,si)
|
||||
c apply that transformation to the columns of matrix g.
|
||||
ic = ij
|
||||
do 680 i=1,nuu
|
||||
call fprota(co,si,right(i),c(ic))
|
||||
ic = ic+nv7
|
||||
680 continue
|
||||
if(j.eq.4) go to 700
|
||||
c apply that transformation to the rows of (avv) with respect to av2.
|
||||
j1 = j+1
|
||||
do 690 i=j1,4
|
||||
call fprota(co,si,h2(i),av2(ij,i))
|
||||
690 continue
|
||||
700 continue
|
||||
c we update the sum of squared residuals
|
||||
do 705 i=1,nuu
|
||||
sq = sq+right(i)**2
|
||||
705 continue
|
||||
go to 750
|
||||
c rotation into triangle of the new row of (avv), in case the elements
|
||||
c corresponding to the b-splines n(j;v),j=nv7+1,...,nv4 are all zero.
|
||||
710 irot =nrold
|
||||
do 740 i=1,5
|
||||
irot = irot+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 740
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,av1(irot,1),co,si)
|
||||
c apply that transformation to the columns of matrix g.
|
||||
ic = irot
|
||||
do 720 j=1,nuu
|
||||
call fprota(co,si,right(j),c(ic))
|
||||
ic = ic+nv7
|
||||
720 continue
|
||||
c apply that transformation to the rows of (avv).
|
||||
if(i.eq.5) go to 740
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 730 j=i3,5
|
||||
i2 = i2+1
|
||||
call fprota(co,si,h(j),av1(irot,i2))
|
||||
730 continue
|
||||
740 continue
|
||||
c we update the sum of squared residuals
|
||||
do 745 i=1,nuu
|
||||
sq = sq+right(i)**2
|
||||
745 continue
|
||||
750 if(nrold.eq.number) go to 770
|
||||
760 nrold = nrold+1
|
||||
go to 450
|
||||
770 continue
|
||||
c test whether the b-spline coefficients must be determined.
|
||||
if(iback.ne.0) return
|
||||
c backward substitution to obtain the b-spline coefficients as the
|
||||
c solution of the linear system (rv) (cr) (ru)' = h.
|
||||
c first step: solve the system (rv) (c1) = h.
|
||||
k = 1
|
||||
do 780 i=1,nuu
|
||||
call fpbacp(av1,av2,c(k),nv7,4,c(k),5,nv)
|
||||
k = k+nv7
|
||||
780 continue
|
||||
c second step: solve the system (cr) (ru)' = (c1).
|
||||
k = 0
|
||||
do 800 j=1,nv7
|
||||
k = k+1
|
||||
l = k
|
||||
do 790 i=1,nuu
|
||||
right(i) = c(l)
|
||||
l = l+nv7
|
||||
790 continue
|
||||
call fpback(au,right,nuu,5,right,nu)
|
||||
l = k
|
||||
do 795 i=1,nuu
|
||||
c(l) = right(i)
|
||||
l = l+nv7
|
||||
795 continue
|
||||
800 continue
|
||||
c calculate from the conditions (2)-(3)-(4), the remaining b-spline
|
||||
c coefficients.
|
||||
ncof = nu4*nv4
|
||||
i = nv4
|
||||
j = 0
|
||||
do 805 l=1,nv4
|
||||
q(l) = dz1
|
||||
805 continue
|
||||
if(iop0.eq.0) go to 815
|
||||
do 810 l=1,nv4
|
||||
i = i+1
|
||||
q(i) = cc(l)
|
||||
810 continue
|
||||
815 if(nuu.eq.0) go to 850
|
||||
do 840 l=1,nuu
|
||||
ii = i
|
||||
do 820 k=1,nv7
|
||||
i = i+1
|
||||
j = j+1
|
||||
q(i) = c(j)
|
||||
820 continue
|
||||
do 830 k=1,3
|
||||
ii = ii+1
|
||||
i = i+1
|
||||
q(i) = q(ii)
|
||||
830 continue
|
||||
840 continue
|
||||
850 if(iop1.eq.0) go to 870
|
||||
do 860 l=1,nv4
|
||||
i = i+1
|
||||
q(i) = 0.
|
||||
860 continue
|
||||
870 do 880 i=1,ncof
|
||||
c(i) = q(i)
|
||||
880 continue
|
||||
c calculate the quantities
|
||||
c res(i,j) = (z(i,j) - s(u(i),v(j)))**2 , i=1,2,..,mu;j=1,2,..,mv
|
||||
c fp = sumi=1,mu(sumj=1,mv(res(i,j)))
|
||||
c fpu(r) = sum''i(sumj=1,mv(res(i,j))) , r=1,2,...,nu-7
|
||||
c tu(r+3) <= u(i) <= tu(r+4)
|
||||
c fpv(r) = sumi=1,mu(sum''j(res(i,j))) , r=1,2,...,nv-7
|
||||
c tv(r+3) <= v(j) <= tv(r+4)
|
||||
fp = 0.
|
||||
do 890 i=1,nu
|
||||
fpu(i) = 0.
|
||||
890 continue
|
||||
do 900 i=1,nv
|
||||
fpv(i) = 0.
|
||||
900 continue
|
||||
iz = 0
|
||||
nroldu = 0
|
||||
c main loop for the different grid points.
|
||||
do 950 i1=1,mu
|
||||
numu = nru(i1)
|
||||
numu1 = numu+1
|
||||
nroldv = 0
|
||||
do 940 i2=1,mv
|
||||
numv = nrv(i2)
|
||||
numv1 = numv+1
|
||||
iz = iz+1
|
||||
c evaluate s(u,v) at the current grid point by making the sum of the
|
||||
c cross products of the non-zero b-splines at (u,v), multiplied with
|
||||
c the appropriate b-spline coefficients.
|
||||
term = 0.
|
||||
k1 = numu*nv4+numv
|
||||
do 920 l1=1,4
|
||||
k2 = k1
|
||||
fac = spu(i1,l1)
|
||||
do 910 l2=1,4
|
||||
k2 = k2+1
|
||||
term = term+fac*spv(i2,l2)*c(k2)
|
||||
910 continue
|
||||
k1 = k1+nv4
|
||||
920 continue
|
||||
c calculate the squared residual at the current grid point.
|
||||
term = (z(iz)-term)**2
|
||||
c adjust the different parameters.
|
||||
fp = fp+term
|
||||
fpu(numu1) = fpu(numu1)+term
|
||||
fpv(numv1) = fpv(numv1)+term
|
||||
fac = term*half
|
||||
if(numv.eq.nroldv) go to 930
|
||||
fpv(numv1) = fpv(numv1)-fac
|
||||
fpv(numv) = fpv(numv)+fac
|
||||
930 nroldv = numv
|
||||
if(numu.eq.nroldu) go to 940
|
||||
fpu(numu1) = fpu(numu1)-fac
|
||||
fpu(numu) = fpu(numu)+fac
|
||||
940 continue
|
||||
nroldu = numu
|
||||
950 continue
|
||||
return
|
||||
end
|
||||
314
cxx/fitpack/fpgrpa.f
Normal file
314
cxx/fitpack/fpgrpa.f
Normal file
@ -0,0 +1,314 @@
|
||||
recursive subroutine fpgrpa(ifsu,ifsv,ifbu,ifbv,idim,ipar,u,mu,
|
||||
* v,mv,z,mz,tu,nu,tv,nv,p,c,nc,fp,fpu,fpv,mm,mvnu,spu,spv,
|
||||
* right,q,au,au1,av,av1,bu,bv,nru,nrv)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 p,fp
|
||||
integer ifsu,ifsv,ifbu,ifbv,idim,mu,mv,mz,nu,nv,nc,mm,mvnu
|
||||
c ..array arguments..
|
||||
real*8 u(mu),v(mv),z(mz*idim),tu(nu),tv(nv),c(nc*idim),fpu(nu),
|
||||
* fpv(nv),spu(mu,4),spv(mv,4),right(mm*idim),q(mvnu),au(nu,5),
|
||||
* au1(nu,4),av(nv,5),av1(nv,4),bu(nu,5),bv(nv,5)
|
||||
integer ipar(2),nru(mu),nrv(mv)
|
||||
c ..local scalars..
|
||||
real*8 arg,fac,term,one,half,value
|
||||
integer i,id,ii,it,iz,i1,i2,j,jz,k,k1,k2,l,l1,l2,mvv,k0,muu,
|
||||
* ncof,nroldu,nroldv,number,nmd,numu,numu1,numv,numv1,nuu,nvv,
|
||||
* nu4,nu7,nu8,nv4,nv7,nv8, n33
|
||||
c ..local arrays..
|
||||
real*8 h(5)
|
||||
c ..subroutine references..
|
||||
c fpback,fpbspl,fpdisc,fpbacp,fptrnp,fptrpe
|
||||
c ..
|
||||
c let
|
||||
c | (spu) | | (spv) |
|
||||
c (au) = | ---------- | (av) = | ---------- |
|
||||
c | (1/p) (bu) | | (1/p) (bv) |
|
||||
c
|
||||
c | z ' 0 |
|
||||
c q = | ------ |
|
||||
c | 0 ' 0 |
|
||||
c
|
||||
c with c : the (nu-4) x (nv-4) matrix which contains the b-spline
|
||||
c coefficients.
|
||||
c z : the mu x mv matrix which contains the function values.
|
||||
c spu,spv: the mu x (nu-4), resp. mv x (nv-4) observation matrices
|
||||
c according to the least-squares problems in the u-,resp.
|
||||
c v-direction.
|
||||
c bu,bv : the (nu-7) x (nu-4),resp. (nv-7) x (nv-4) matrices
|
||||
c containing the discontinuity jumps of the derivatives
|
||||
c of the b-splines in the u-,resp.v-variable at the knots
|
||||
c the b-spline coefficients of the smoothing spline are then calculated
|
||||
c as the least-squares solution of the following over-determined linear
|
||||
c system of equations
|
||||
c
|
||||
c (1) (av) c (au)' = q
|
||||
c
|
||||
c subject to the constraints
|
||||
c
|
||||
c (2) c(nu-3+i,j) = c(i,j), i=1,2,3 ; j=1,2,...,nv-4
|
||||
c if(ipar(1).ne.0)
|
||||
c
|
||||
c (3) c(i,nv-3+j) = c(i,j), j=1,2,3 ; i=1,2,...,nu-4
|
||||
c if(ipar(2).ne.0)
|
||||
c
|
||||
c set constants
|
||||
one = 1
|
||||
half = 0.5
|
||||
c initialization
|
||||
nu4 = nu-4
|
||||
nu7 = nu-7
|
||||
nu8 = nu-8
|
||||
nv4 = nv-4
|
||||
nv7 = nv-7
|
||||
nv8 = nv-8
|
||||
muu = mu
|
||||
if(ipar(1).ne.0) muu = mu-1
|
||||
mvv = mv
|
||||
if(ipar(2).ne.0) mvv = mv-1
|
||||
c it depends on the value of the flags ifsu,ifsv,ifbu and ibvand
|
||||
c on the value of p whether the matrices (spu), (spv), (bu) and (bv)
|
||||
c still must be determined.
|
||||
if(ifsu.ne.0) go to 50
|
||||
c calculate the non-zero elements of the matrix (spu) which is the ob-
|
||||
c servation matrix according to the least-squares spline approximation
|
||||
c problem in the u-direction.
|
||||
l = 4
|
||||
l1 = 5
|
||||
number = 0
|
||||
do 40 it=1,muu
|
||||
arg = u(it)
|
||||
10 if(arg.lt.tu(l1) .or. l.eq.nu4) go to 20
|
||||
l = l1
|
||||
l1 = l+1
|
||||
number = number+1
|
||||
go to 10
|
||||
20 call fpbspl(tu,nu,3,arg,l,h)
|
||||
do 30 i=1,4
|
||||
spu(it,i) = h(i)
|
||||
30 continue
|
||||
nru(it) = number
|
||||
40 continue
|
||||
ifsu = 1
|
||||
c calculate the non-zero elements of the matrix (spv) which is the ob-
|
||||
c servation matrix according to the least-squares spline approximation
|
||||
c problem in the v-direction.
|
||||
50 if(ifsv.ne.0) go to 100
|
||||
l = 4
|
||||
l1 = 5
|
||||
number = 0
|
||||
do 90 it=1,mvv
|
||||
arg = v(it)
|
||||
60 if(arg.lt.tv(l1) .or. l.eq.nv4) go to 70
|
||||
l = l1
|
||||
l1 = l+1
|
||||
number = number+1
|
||||
go to 60
|
||||
70 call fpbspl(tv,nv,3,arg,l,h)
|
||||
do 80 i=1,4
|
||||
spv(it,i) = h(i)
|
||||
80 continue
|
||||
nrv(it) = number
|
||||
90 continue
|
||||
ifsv = 1
|
||||
100 if(p.le.0.) go to 150
|
||||
c calculate the non-zero elements of the matrix (bu).
|
||||
if(ifbu.ne.0 .or. nu8.eq.0) go to 110
|
||||
call fpdisc(tu,nu,5,bu,nu)
|
||||
ifbu = 1
|
||||
c calculate the non-zero elements of the matrix (bv).
|
||||
110 if(ifbv.ne.0 .or. nv8.eq.0) go to 150
|
||||
call fpdisc(tv,nv,5,bv,nv)
|
||||
ifbv = 1
|
||||
c substituting (2) and (3) into (1), we obtain the overdetermined
|
||||
c system
|
||||
c (4) (avv) (cr) (auu)' = (qq)
|
||||
c from which the nuu*nvv remaining coefficients
|
||||
c c(i,j) , i=1,...,nu-4-3*ipar(1) ; j=1,...,nv-4-3*ipar(2) ,
|
||||
c the elements of (cr), are then determined in the least-squares sense.
|
||||
c we first determine the matrices (auu) and (qq). then we reduce the
|
||||
c matrix (auu) to upper triangular form (ru) using givens rotations.
|
||||
c we apply the same transformations to the rows of matrix qq to obtain
|
||||
c the (mv) x nuu matrix g.
|
||||
c we store matrix (ru) into au (and au1 if ipar(1)=1) and g into q.
|
||||
150 if(ipar(1).ne.0) go to 160
|
||||
nuu = nu4
|
||||
call fptrnp(mu,mv,idim,nu,nru,spu,p,bu,z,au,q,right)
|
||||
go to 180
|
||||
160 nuu = nu7
|
||||
call fptrpe(mu,mv,idim,nu,nru,spu,p,bu,z,au,au1,q,right)
|
||||
c we determine the matrix (avv) and then we reduce this matrix to
|
||||
c upper triangular form (rv) using givens rotations.
|
||||
c we apply the same transformations to the columns of matrix
|
||||
c g to obtain the (nvv) x (nuu) matrix h.
|
||||
c we store matrix (rv) into av (and av1 if ipar(2)=1) and h into c.
|
||||
180 if(ipar(2).ne.0) go to 190
|
||||
nvv = nv4
|
||||
call fptrnp(mv,nuu,idim,nv,nrv,spv,p,bv,q,av,c,right)
|
||||
go to 200
|
||||
190 nvv = nv7
|
||||
call fptrpe(mv,nuu,idim,nv,nrv,spv,p,bv,q,av,av1,c,right)
|
||||
c backward substitution to obtain the b-spline coefficients as the
|
||||
c solution of the linear system (rv) (cr) (ru)' = h.
|
||||
c first step: solve the system (rv) (c1) = h.
|
||||
200 ncof = nuu*nvv
|
||||
k = 1
|
||||
if(ipar(2).ne.0) go to 240
|
||||
do 220 ii=1,idim
|
||||
do 220 i=1,nuu
|
||||
call fpback(av,c(k),nvv,5,c(k),nv)
|
||||
k = k+nvv
|
||||
220 continue
|
||||
go to 300
|
||||
240 do 260 ii=1,idim
|
||||
do 260 i=1,nuu
|
||||
call fpbacp(av,av1,c(k),nvv,4,c(k),5,nv)
|
||||
k = k+nvv
|
||||
260 continue
|
||||
c second step: solve the system (cr) (ru)' = (c1).
|
||||
300 if(ipar(1).ne.0) go to 400
|
||||
do 360 ii=1,idim
|
||||
k = (ii-1)*ncof
|
||||
do 360 j=1,nvv
|
||||
k = k+1
|
||||
l = k
|
||||
do 320 i=1,nuu
|
||||
right(i) = c(l)
|
||||
l = l+nvv
|
||||
320 continue
|
||||
call fpback(au,right,nuu,5,right,nu)
|
||||
l = k
|
||||
do 340 i=1,nuu
|
||||
c(l) = right(i)
|
||||
l = l+nvv
|
||||
340 continue
|
||||
360 continue
|
||||
go to 500
|
||||
400 do 460 ii=1,idim
|
||||
k = (ii-1)*ncof
|
||||
do 460 j=1,nvv
|
||||
k = k+1
|
||||
l = k
|
||||
do 420 i=1,nuu
|
||||
right(i) = c(l)
|
||||
l = l+nvv
|
||||
420 continue
|
||||
call fpbacp(au,au1,right,nuu,4,right,5,nu)
|
||||
l = k
|
||||
do 440 i=1,nuu
|
||||
c(l) = right(i)
|
||||
l = l+nvv
|
||||
440 continue
|
||||
460 continue
|
||||
c calculate from the conditions (2)-(3), the remaining b-spline
|
||||
c coefficients.
|
||||
500 if(ipar(2).eq.0) go to 600
|
||||
i = 0
|
||||
j = 0
|
||||
do 560 id=1,idim
|
||||
do 560 l=1,nuu
|
||||
ii = i
|
||||
do 520 k=1,nvv
|
||||
i = i+1
|
||||
j = j+1
|
||||
q(i) = c(j)
|
||||
520 continue
|
||||
do 540 k=1,3
|
||||
ii = ii+1
|
||||
i = i+1
|
||||
q(i) = q(ii)
|
||||
540 continue
|
||||
560 continue
|
||||
ncof = nv4*nuu
|
||||
nmd = ncof*idim
|
||||
do 580 i=1,nmd
|
||||
c(i) = q(i)
|
||||
580 continue
|
||||
600 if(ipar(1).eq.0) go to 700
|
||||
i = 0
|
||||
j = 0
|
||||
n33 = 3*nv4
|
||||
do 660 id=1,idim
|
||||
ii = i
|
||||
do 620 k=1,ncof
|
||||
i = i+1
|
||||
j = j+1
|
||||
q(i) = c(j)
|
||||
620 continue
|
||||
do 640 k=1,n33
|
||||
ii = ii+1
|
||||
i = i+1
|
||||
q(i) = q(ii)
|
||||
640 continue
|
||||
660 continue
|
||||
ncof = nv4*nu4
|
||||
nmd = ncof*idim
|
||||
do 680 i=1,nmd
|
||||
c(i) = q(i)
|
||||
680 continue
|
||||
c calculate the quantities
|
||||
c res(i,j) = (z(i,j) - s(u(i),v(j)))**2 , i=1,2,..,mu;j=1,2,..,mv
|
||||
c fp = sumi=1,mu(sumj=1,mv(res(i,j)))
|
||||
c fpu(r) = sum''i(sumj=1,mv(res(i,j))) , r=1,2,...,nu-7
|
||||
c tu(r+3) <= u(i) <= tu(r+4)
|
||||
c fpv(r) = sumi=1,mu(sum''j(res(i,j))) , r=1,2,...,nv-7
|
||||
c tv(r+3) <= v(j) <= tv(r+4)
|
||||
700 fp = 0.
|
||||
do 720 i=1,nu
|
||||
fpu(i) = 0.
|
||||
720 continue
|
||||
do 740 i=1,nv
|
||||
fpv(i) = 0.
|
||||
740 continue
|
||||
nroldu = 0
|
||||
c main loop for the different grid points.
|
||||
do 860 i1=1,muu
|
||||
numu = nru(i1)
|
||||
numu1 = numu+1
|
||||
nroldv = 0
|
||||
iz = (i1-1)*mv
|
||||
do 840 i2=1,mvv
|
||||
numv = nrv(i2)
|
||||
numv1 = numv+1
|
||||
iz = iz+1
|
||||
c evaluate s(u,v) at the current grid point by making the sum of the
|
||||
c cross products of the non-zero b-splines at (u,v), multiplied with
|
||||
c the appropriate b-spline coefficients.
|
||||
term = 0.
|
||||
k0 = numu*nv4+numv
|
||||
jz = iz
|
||||
do 800 id=1,idim
|
||||
k1 = k0
|
||||
value = 0.
|
||||
do 780 l1=1,4
|
||||
k2 = k1
|
||||
fac = spu(i1,l1)
|
||||
do 760 l2=1,4
|
||||
k2 = k2+1
|
||||
value = value+fac*spv(i2,l2)*c(k2)
|
||||
760 continue
|
||||
k1 = k1+nv4
|
||||
780 continue
|
||||
c calculate the squared residual at the current grid point.
|
||||
term = term+(z(jz)-value)**2
|
||||
jz = jz+mz
|
||||
k0 = k0+ncof
|
||||
800 continue
|
||||
c adjust the different parameters.
|
||||
fp = fp+term
|
||||
fpu(numu1) = fpu(numu1)+term
|
||||
fpv(numv1) = fpv(numv1)+term
|
||||
fac = term*half
|
||||
if(numv.eq.nroldv) go to 820
|
||||
fpv(numv1) = fpv(numv1)-fac
|
||||
fpv(numv) = fpv(numv)+fac
|
||||
820 nroldv = numv
|
||||
if(numu.eq.nroldu) go to 840
|
||||
fpu(numu1) = fpu(numu1)-fac
|
||||
fpu(numu) = fpu(numu)+fac
|
||||
840 continue
|
||||
nroldu = numu
|
||||
860 continue
|
||||
return
|
||||
end
|
||||
329
cxx/fitpack/fpgrre.f
Normal file
329
cxx/fitpack/fpgrre.f
Normal file
@ -0,0 +1,329 @@
|
||||
recursive subroutine fpgrre(ifsx,ifsy,ifbx,ifby,x,mx,y,my,z,mz,
|
||||
* kx,ky,tx,nx,ty,ny,p,c,nc,fp,fpx,fpy,mm,mynx,kx1,kx2,ky1,ky2,
|
||||
* spx,spy,right,q,ax,ay,bx,by,nrx,nry)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 p,fp
|
||||
integer ifsx,ifsy,ifbx,ifby,mx,my,mz,kx,ky,nx,ny,nc,mm,mynx,
|
||||
* kx1,kx2,ky1,ky2
|
||||
c ..array arguments..
|
||||
real*8 x(mx),y(my),z(mz),tx(nx),ty(ny),c(nc),spx(mx,kx1),spy(my,ky
|
||||
*1)
|
||||
* ,right(mm),q(mynx),ax(nx,kx2),bx(nx,kx2),ay(ny,ky2),by(ny,ky2),
|
||||
* fpx(nx),fpy(ny)
|
||||
integer nrx(mx),nry(my)
|
||||
c ..local scalars..
|
||||
real*8 arg,cos,fac,pinv,piv,sin,term,one,half
|
||||
integer i,ibandx,ibandy,ic,iq,irot,it,iz,i1,i2,i3,j,k,k1,k2,l,
|
||||
* l1,l2,ncof,nk1x,nk1y,nrold,nroldx,nroldy,number,numx,numx1,
|
||||
* numy,numy1,n1
|
||||
c ..local arrays..
|
||||
real*8 h(7)
|
||||
c ..subroutine references..
|
||||
c fpback,fpbspl,fpgivs,fpdisc,fprota
|
||||
c ..
|
||||
c the b-spline coefficients of the smoothing spline are calculated as
|
||||
c the least-squares solution of the over-determined linear system of
|
||||
c equations (ay) c (ax)' = q where
|
||||
c
|
||||
c | (spx) | | (spy) |
|
||||
c (ax) = | ---------- | (ay) = | ---------- |
|
||||
c | (1/p) (bx) | | (1/p) (by) |
|
||||
c
|
||||
c | z ' 0 |
|
||||
c q = | ------ |
|
||||
c | 0 ' 0 |
|
||||
c
|
||||
c with c : the (ny-ky-1) x (nx-kx-1) matrix which contains the
|
||||
c b-spline coefficients.
|
||||
c z : the my x mx matrix which contains the function values.
|
||||
c spx,spy: the mx x (nx-kx-1) and my x (ny-ky-1) observation
|
||||
c matrices according to the least-squares problems in
|
||||
c the x- and y-direction.
|
||||
c bx,by : the (nx-2*kx-1) x (nx-kx-1) and (ny-2*ky-1) x (ny-ky-1)
|
||||
c matrices which contain the discontinuity jumps of the
|
||||
c derivatives of the b-splines in the x- and y-direction.
|
||||
one = 1
|
||||
half = 0.5
|
||||
nk1x = nx-kx1
|
||||
nk1y = ny-ky1
|
||||
if(p.gt.0.) pinv = one/p
|
||||
c it depends on the value of the flags ifsx,ifsy,ifbx and ifby and on
|
||||
c the value of p whether the matrices (spx),(spy),(bx) and (by) still
|
||||
c must be determined.
|
||||
if(ifsx.ne.0) go to 50
|
||||
c calculate the non-zero elements of the matrix (spx) which is the
|
||||
c observation matrix according to the least-squares spline approximat-
|
||||
c ion problem in the x-direction.
|
||||
l = kx1
|
||||
l1 = kx2
|
||||
number = 0
|
||||
do 40 it=1,mx
|
||||
arg = x(it)
|
||||
10 if(arg.lt.tx(l1) .or. l.eq.nk1x) go to 20
|
||||
l = l1
|
||||
l1 = l+1
|
||||
number = number+1
|
||||
go to 10
|
||||
20 call fpbspl(tx,nx,kx,arg,l,h)
|
||||
do 30 i=1,kx1
|
||||
spx(it,i) = h(i)
|
||||
30 continue
|
||||
nrx(it) = number
|
||||
40 continue
|
||||
ifsx = 1
|
||||
50 if(ifsy.ne.0) go to 100
|
||||
c calculate the non-zero elements of the matrix (spy) which is the
|
||||
c observation matrix according to the least-squares spline approximat-
|
||||
c ion problem in the y-direction.
|
||||
l = ky1
|
||||
l1 = ky2
|
||||
number = 0
|
||||
do 90 it=1,my
|
||||
arg = y(it)
|
||||
60 if(arg.lt.ty(l1) .or. l.eq.nk1y) go to 70
|
||||
l = l1
|
||||
l1 = l+1
|
||||
number = number+1
|
||||
go to 60
|
||||
70 call fpbspl(ty,ny,ky,arg,l,h)
|
||||
do 80 i=1,ky1
|
||||
spy(it,i) = h(i)
|
||||
80 continue
|
||||
nry(it) = number
|
||||
90 continue
|
||||
ifsy = 1
|
||||
100 if(p.le.0.) go to 120
|
||||
c calculate the non-zero elements of the matrix (bx).
|
||||
if(ifbx.ne.0 .or. nx.eq.2*kx1) go to 110
|
||||
call fpdisc(tx,nx,kx2,bx,nx)
|
||||
ifbx = 1
|
||||
c calculate the non-zero elements of the matrix (by).
|
||||
110 if(ifby.ne.0 .or. ny.eq.2*ky1) go to 120
|
||||
call fpdisc(ty,ny,ky2,by,ny)
|
||||
ifby = 1
|
||||
c reduce the matrix (ax) to upper triangular form (rx) using givens
|
||||
c rotations. apply the same transformations to the rows of matrix q
|
||||
c to obtain the my x (nx-kx-1) matrix g.
|
||||
c store matrix (rx) into (ax) and g into q.
|
||||
120 l = my*nk1x
|
||||
c initialization.
|
||||
do 130 i=1,l
|
||||
q(i) = 0.
|
||||
130 continue
|
||||
do 140 i=1,nk1x
|
||||
do 140 j=1,kx2
|
||||
ax(i,j) = 0.
|
||||
140 continue
|
||||
l = 0
|
||||
nrold = 0
|
||||
c ibandx denotes the bandwidth of the matrices (ax) and (rx).
|
||||
ibandx = kx1
|
||||
do 270 it=1,mx
|
||||
number = nrx(it)
|
||||
150 if(nrold.eq.number) go to 180
|
||||
if(p.le.0.) go to 260
|
||||
ibandx = kx2
|
||||
c fetch a new row of matrix (bx).
|
||||
n1 = nrold+1
|
||||
do 160 j=1,kx2
|
||||
h(j) = bx(n1,j)*pinv
|
||||
160 continue
|
||||
c find the appropriate column of q.
|
||||
do 170 j=1,my
|
||||
right(j) = 0.
|
||||
170 continue
|
||||
irot = nrold
|
||||
go to 210
|
||||
c fetch a new row of matrix (spx).
|
||||
180 h(ibandx) = 0.
|
||||
do 190 j=1,kx1
|
||||
h(j) = spx(it,j)
|
||||
190 continue
|
||||
c find the appropriate column of q.
|
||||
do 200 j=1,my
|
||||
l = l+1
|
||||
right(j) = z(l)
|
||||
200 continue
|
||||
irot = number
|
||||
c rotate the new row of matrix (ax) into triangle.
|
||||
210 do 240 i=1,ibandx
|
||||
irot = irot+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 240
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,ax(irot,1),cos,sin)
|
||||
c apply that transformation to the rows of matrix q.
|
||||
iq = (irot-1)*my
|
||||
do 220 j=1,my
|
||||
iq = iq+1
|
||||
call fprota(cos,sin,right(j),q(iq))
|
||||
220 continue
|
||||
c apply that transformation to the columns of (ax).
|
||||
if(i.eq.ibandx) go to 250
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 230 j=i3,ibandx
|
||||
i2 = i2+1
|
||||
call fprota(cos,sin,h(j),ax(irot,i2))
|
||||
230 continue
|
||||
240 continue
|
||||
250 if(nrold.eq.number) go to 270
|
||||
260 nrold = nrold+1
|
||||
go to 150
|
||||
270 continue
|
||||
c reduce the matrix (ay) to upper triangular form (ry) using givens
|
||||
c rotations. apply the same transformations to the columns of matrix g
|
||||
c to obtain the (ny-ky-1) x (nx-kx-1) matrix h.
|
||||
c store matrix (ry) into (ay) and h into c.
|
||||
ncof = nk1x*nk1y
|
||||
c initialization.
|
||||
do 280 i=1,ncof
|
||||
c(i) = 0.
|
||||
280 continue
|
||||
do 290 i=1,nk1y
|
||||
do 290 j=1,ky2
|
||||
ay(i,j) = 0.
|
||||
290 continue
|
||||
nrold = 0
|
||||
c ibandy denotes the bandwidth of the matrices (ay) and (ry).
|
||||
ibandy = ky1
|
||||
do 420 it=1,my
|
||||
number = nry(it)
|
||||
300 if(nrold.eq.number) go to 330
|
||||
if(p.le.0.) go to 410
|
||||
ibandy = ky2
|
||||
c fetch a new row of matrix (by).
|
||||
n1 = nrold+1
|
||||
do 310 j=1,ky2
|
||||
h(j) = by(n1,j)*pinv
|
||||
310 continue
|
||||
c find the appropriate row of g.
|
||||
do 320 j=1,nk1x
|
||||
right(j) = 0.
|
||||
320 continue
|
||||
irot = nrold
|
||||
go to 360
|
||||
c fetch a new row of matrix (spy)
|
||||
330 h(ibandy) = 0.
|
||||
do 340 j=1,ky1
|
||||
h(j) = spy(it,j)
|
||||
340 continue
|
||||
c find the appropriate row of g.
|
||||
l = it
|
||||
do 350 j=1,nk1x
|
||||
right(j) = q(l)
|
||||
l = l+my
|
||||
350 continue
|
||||
irot = number
|
||||
c rotate the new row of matrix (ay) into triangle.
|
||||
360 do 390 i=1,ibandy
|
||||
irot = irot+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 390
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,ay(irot,1),cos,sin)
|
||||
c apply that transformation to the columns of matrix g.
|
||||
ic = irot
|
||||
do 370 j=1,nk1x
|
||||
call fprota(cos,sin,right(j),c(ic))
|
||||
ic = ic+nk1y
|
||||
370 continue
|
||||
c apply that transformation to the columns of matrix (ay).
|
||||
if(i.eq.ibandy) go to 400
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 380 j=i3,ibandy
|
||||
i2 = i2+1
|
||||
call fprota(cos,sin,h(j),ay(irot,i2))
|
||||
380 continue
|
||||
390 continue
|
||||
400 if(nrold.eq.number) go to 420
|
||||
410 nrold = nrold+1
|
||||
go to 300
|
||||
420 continue
|
||||
c backward substitution to obtain the b-spline coefficients as the
|
||||
c solution of the linear system (ry) c (rx)' = h.
|
||||
c first step: solve the system (ry) (c1) = h.
|
||||
k = 1
|
||||
do 450 i=1,nk1x
|
||||
call fpback(ay,c(k),nk1y,ibandy,c(k),ny)
|
||||
k = k+nk1y
|
||||
450 continue
|
||||
c second step: solve the system c (rx)' = (c1).
|
||||
k = 0
|
||||
do 480 j=1,nk1y
|
||||
k = k+1
|
||||
l = k
|
||||
do 460 i=1,nk1x
|
||||
right(i) = c(l)
|
||||
l = l+nk1y
|
||||
460 continue
|
||||
call fpback(ax,right,nk1x,ibandx,right,nx)
|
||||
l = k
|
||||
do 470 i=1,nk1x
|
||||
c(l) = right(i)
|
||||
l = l+nk1y
|
||||
470 continue
|
||||
480 continue
|
||||
c calculate the quantities
|
||||
c res(i,j) = (z(i,j) - s(x(i),y(j)))**2 , i=1,2,..,mx;j=1,2,..,my
|
||||
c fp = sumi=1,mx(sumj=1,my(res(i,j)))
|
||||
c fpx(r) = sum''i(sumj=1,my(res(i,j))) , r=1,2,...,nx-2*kx-1
|
||||
c tx(r+kx) <= x(i) <= tx(r+kx+1)
|
||||
c fpy(r) = sumi=1,mx(sum''j(res(i,j))) , r=1,2,...,ny-2*ky-1
|
||||
c ty(r+ky) <= y(j) <= ty(r+ky+1)
|
||||
fp = 0.
|
||||
do 490 i=1,nx
|
||||
fpx(i) = 0.
|
||||
490 continue
|
||||
do 500 i=1,ny
|
||||
fpy(i) = 0.
|
||||
500 continue
|
||||
nk1y = ny-ky1
|
||||
iz = 0
|
||||
nroldx = 0
|
||||
c main loop for the different grid points.
|
||||
do 550 i1=1,mx
|
||||
numx = nrx(i1)
|
||||
numx1 = numx+1
|
||||
nroldy = 0
|
||||
do 540 i2=1,my
|
||||
numy = nry(i2)
|
||||
numy1 = numy+1
|
||||
iz = iz+1
|
||||
c evaluate s(x,y) at the current grid point by making the sum of the
|
||||
c cross products of the non-zero b-splines at (x,y), multiplied with
|
||||
c the appropriate b-spline coefficients.
|
||||
term = 0.
|
||||
k1 = numx*nk1y+numy
|
||||
do 520 l1=1,kx1
|
||||
k2 = k1
|
||||
fac = spx(i1,l1)
|
||||
do 510 l2=1,ky1
|
||||
k2 = k2+1
|
||||
term = term+fac*spy(i2,l2)*c(k2)
|
||||
510 continue
|
||||
k1 = k1+nk1y
|
||||
520 continue
|
||||
c calculate the squared residual at the current grid point.
|
||||
term = (z(iz)-term)**2
|
||||
c adjust the different parameters.
|
||||
fp = fp+term
|
||||
fpx(numx1) = fpx(numx1)+term
|
||||
fpy(numy1) = fpy(numy1)+term
|
||||
fac = term*half
|
||||
if(numy.eq.nroldy) go to 530
|
||||
fpy(numy1) = fpy(numy1)-fac
|
||||
fpy(numy) = fpy(numy)+fac
|
||||
530 nroldy = numy
|
||||
if(numx.eq.nroldx) go to 540
|
||||
fpx(numx1) = fpx(numx1)-fac
|
||||
fpx(numx) = fpx(numx)+fac
|
||||
540 continue
|
||||
nroldx = numx
|
||||
550 continue
|
||||
return
|
||||
end
|
||||
|
||||
658
cxx/fitpack/fpgrsp.f
Normal file
658
cxx/fitpack/fpgrsp.f
Normal file
@ -0,0 +1,658 @@
|
||||
recursive subroutine fpgrsp(ifsu,ifsv,ifbu,ifbv,iback,u,mu,v,
|
||||
* mv,r,mr,dr,iop0,iop1,tu,nu,tv,nv,p,c,nc,sq,fp,fpu,fpv,mm,
|
||||
* mvnu,spu,spv,right,q,au,av1,av2,bu,bv,a0,a1,b0,b1,c0,c1,
|
||||
* cosi,nru,nrv)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 p,sq,fp
|
||||
integer ifsu,ifsv,ifbu,ifbv,iback,mu,mv,mr,iop0,iop1,nu,nv,nc,
|
||||
* mm,mvnu
|
||||
c ..array arguments..
|
||||
real*8 u(mu),v(mv),r(mr),dr(6),tu(nu),tv(nv),c(nc),fpu(nu),fpv(nv)
|
||||
*,
|
||||
* spu(mu,4),spv(mv,4),right(mm),q(mvnu),au(nu,5),av1(nv,6),c0(nv),
|
||||
* av2(nv,4),a0(2,mv),b0(2,nv),cosi(2,nv),bu(nu,5),bv(nv,5),c1(nv),
|
||||
* a1(2,mv),b1(2,nv)
|
||||
integer nru(mu),nrv(mv)
|
||||
c ..local scalars..
|
||||
real*8 arg,co,dr01,dr02,dr03,dr11,dr12,dr13,fac,fac0,fac1,pinv,piv
|
||||
*,
|
||||
* si,term,one,three,half
|
||||
integer i,ic,ii,ij,ik,iq,irot,it,ir,i0,i1,i2,i3,j,jj,jk,jper,
|
||||
* j0,j1,k,k1,k2,l,l0,l1,l2,mvv,ncof,nrold,nroldu,nroldv,number,
|
||||
* numu,numu1,numv,numv1,nuu,nu4,nu7,nu8,nu9,nv11,nv4,nv7,nv8,n1
|
||||
c ..local arrays..
|
||||
real*8 h(5),h1(5),h2(4)
|
||||
c ..function references..
|
||||
integer min0
|
||||
real*8 cos,sin
|
||||
c ..subroutine references..
|
||||
c fpback,fpbspl,fpgivs,fpcyt1,fpcyt2,fpdisc,fpbacp,fprota
|
||||
c ..
|
||||
c let
|
||||
c | (spu) | | (spv) |
|
||||
c (au) = | -------------- | (av) = | -------------- |
|
||||
c | sqrt(1/p) (bu) | | sqrt(1/p) (bv) |
|
||||
c
|
||||
c | r ' 0 |
|
||||
c q = | ------ |
|
||||
c | 0 ' 0 |
|
||||
c
|
||||
c with c : the (nu-4) x (nv-4) matrix which contains the b-spline
|
||||
c coefficients.
|
||||
c r : the mu x mv matrix which contains the function values.
|
||||
c spu,spv: the mu x (nu-4), resp. mv x (nv-4) observation matrices
|
||||
c according to the least-squares problems in the u-,resp.
|
||||
c v-direction.
|
||||
c bu,bv : the (nu-7) x (nu-4),resp. (nv-7) x (nv-4) matrices
|
||||
c containing the discontinuity jumps of the derivatives
|
||||
c of the b-splines in the u-,resp.v-variable at the knots
|
||||
c the b-spline coefficients of the smoothing spline are then calculated
|
||||
c as the least-squares solution of the following over-determined linear
|
||||
c system of equations
|
||||
c
|
||||
c (1) (av) c (au)' = q
|
||||
c
|
||||
c subject to the constraints
|
||||
c
|
||||
c (2) c(i,nv-3+j) = c(i,j), j=1,2,3 ; i=1,2,...,nu-4
|
||||
c
|
||||
c (3) if iop0 = 0 c(1,j) = dr(1)
|
||||
c iop0 = 1 c(1,j) = dr(1)
|
||||
c c(2,j) = dr(1)+(dr(2)*cosi(1,j)+dr(3)*cosi(2,j))*
|
||||
c tu(5)/3. = c0(j) , j=1,2,...nv-4
|
||||
c
|
||||
c (4) if iop1 = 0 c(nu-4,j) = dr(4)
|
||||
c iop1 = 1 c(nu-4,j) = dr(4)
|
||||
c c(nu-5,j) = dr(4)+(dr(5)*cosi(1,j)+dr(6)*cosi(2,j))
|
||||
c *(tu(nu-4)-tu(nu-3))/3. = c1(j)
|
||||
c
|
||||
c set constants
|
||||
one = 1
|
||||
three = 3
|
||||
half = 0.5
|
||||
c initialization
|
||||
nu4 = nu-4
|
||||
nu7 = nu-7
|
||||
nu8 = nu-8
|
||||
nu9 = nu-9
|
||||
nv4 = nv-4
|
||||
nv7 = nv-7
|
||||
nv8 = nv-8
|
||||
nv11 = nv-11
|
||||
nuu = nu4-iop0-iop1-2
|
||||
if(p.gt.0.) pinv = one/p
|
||||
c it depends on the value of the flags ifsu,ifsv,ifbu,ifbv,iop0,iop1
|
||||
c and on the value of p whether the matrices (spu), (spv), (bu), (bv),
|
||||
c (cosi) still must be determined.
|
||||
if(ifsu.ne.0) go to 30
|
||||
c calculate the non-zero elements of the matrix (spu) which is the ob-
|
||||
c servation matrix according to the least-squares spline approximation
|
||||
c problem in the u-direction.
|
||||
l = 4
|
||||
l1 = 5
|
||||
number = 0
|
||||
do 25 it=1,mu
|
||||
arg = u(it)
|
||||
10 if(arg.lt.tu(l1) .or. l.eq.nu4) go to 15
|
||||
l = l1
|
||||
l1 = l+1
|
||||
number = number+1
|
||||
go to 10
|
||||
15 call fpbspl(tu,nu,3,arg,l,h)
|
||||
do 20 i=1,4
|
||||
spu(it,i) = h(i)
|
||||
20 continue
|
||||
nru(it) = number
|
||||
25 continue
|
||||
ifsu = 1
|
||||
c calculate the non-zero elements of the matrix (spv) which is the ob-
|
||||
c servation matrix according to the least-squares spline approximation
|
||||
c problem in the v-direction.
|
||||
30 if(ifsv.ne.0) go to 85
|
||||
l = 4
|
||||
l1 = 5
|
||||
number = 0
|
||||
do 50 it=1,mv
|
||||
arg = v(it)
|
||||
35 if(arg.lt.tv(l1) .or. l.eq.nv4) go to 40
|
||||
l = l1
|
||||
l1 = l+1
|
||||
number = number+1
|
||||
go to 35
|
||||
40 call fpbspl(tv,nv,3,arg,l,h)
|
||||
do 45 i=1,4
|
||||
spv(it,i) = h(i)
|
||||
45 continue
|
||||
nrv(it) = number
|
||||
50 continue
|
||||
ifsv = 1
|
||||
if(iop0.eq.0 .and. iop1.eq.0) go to 85
|
||||
c calculate the coefficients of the interpolating splines for cos(v)
|
||||
c and sin(v).
|
||||
do 55 i=1,nv4
|
||||
cosi(1,i) = 0.
|
||||
cosi(2,i) = 0.
|
||||
55 continue
|
||||
if(nv7.lt.4) go to 85
|
||||
do 65 i=1,nv7
|
||||
l = i+3
|
||||
arg = tv(l)
|
||||
call fpbspl(tv,nv,3,arg,l,h)
|
||||
do 60 j=1,3
|
||||
av1(i,j) = h(j)
|
||||
60 continue
|
||||
cosi(1,i) = cos(arg)
|
||||
cosi(2,i) = sin(arg)
|
||||
65 continue
|
||||
call fpcyt1(av1,nv7,nv)
|
||||
do 80 j=1,2
|
||||
do 70 i=1,nv7
|
||||
right(i) = cosi(j,i)
|
||||
70 continue
|
||||
call fpcyt2(av1,nv7,right,right,nv)
|
||||
do 75 i=1,nv7
|
||||
cosi(j,i+1) = right(i)
|
||||
75 continue
|
||||
cosi(j,1) = cosi(j,nv7+1)
|
||||
cosi(j,nv7+2) = cosi(j,2)
|
||||
cosi(j,nv4) = cosi(j,3)
|
||||
80 continue
|
||||
85 if(p.le.0.) go to 150
|
||||
c calculate the non-zero elements of the matrix (bu).
|
||||
if(ifbu.ne.0 .or. nu8.eq.0) go to 90
|
||||
call fpdisc(tu,nu,5,bu,nu)
|
||||
ifbu = 1
|
||||
c calculate the non-zero elements of the matrix (bv).
|
||||
90 if(ifbv.ne.0 .or. nv8.eq.0) go to 150
|
||||
call fpdisc(tv,nv,5,bv,nv)
|
||||
ifbv = 1
|
||||
c substituting (2),(3) and (4) into (1), we obtain the overdetermined
|
||||
c system
|
||||
c (5) (avv) (cc) (auu)' = (qq)
|
||||
c from which the nuu*nv7 remaining coefficients
|
||||
c c(i,j) , i=2+iop0,3+iop0,...,nu-5-iop1,j=1,2,...,nv-7.
|
||||
c the elements of (cc), are then determined in the least-squares sense.
|
||||
c simultaneously, we compute the resulting sum of squared residuals sq.
|
||||
150 dr01 = dr(1)
|
||||
dr11 = dr(4)
|
||||
do 155 i=1,mv
|
||||
a0(1,i) = dr01
|
||||
a1(1,i) = dr11
|
||||
155 continue
|
||||
if(nv8.eq.0 .or. p.le.0.) go to 165
|
||||
do 160 i=1,nv8
|
||||
b0(1,i) = 0.
|
||||
b1(1,i) = 0.
|
||||
160 continue
|
||||
165 mvv = mv
|
||||
if(iop0.eq.0) go to 195
|
||||
fac = (tu(5)-tu(4))/three
|
||||
dr02 = dr(2)*fac
|
||||
dr03 = dr(3)*fac
|
||||
do 170 i=1,nv4
|
||||
c0(i) = dr01+dr02*cosi(1,i)+dr03*cosi(2,i)
|
||||
170 continue
|
||||
do 180 i=1,mv
|
||||
number = nrv(i)
|
||||
fac = 0.
|
||||
do 175 j=1,4
|
||||
number = number+1
|
||||
fac = fac+c0(number)*spv(i,j)
|
||||
175 continue
|
||||
a0(2,i) = fac
|
||||
180 continue
|
||||
if(nv8.eq.0 .or. p.le.0.) go to 195
|
||||
do 190 i=1,nv8
|
||||
number = i
|
||||
fac = 0.
|
||||
do 185 j=1,5
|
||||
fac = fac+c0(number)*bv(i,j)
|
||||
number = number+1
|
||||
185 continue
|
||||
b0(2,i) = fac*pinv
|
||||
190 continue
|
||||
mvv = mv+nv8
|
||||
195 if(iop1.eq.0) go to 225
|
||||
fac = (tu(nu4)-tu(nu4+1))/three
|
||||
dr12 = dr(5)*fac
|
||||
dr13 = dr(6)*fac
|
||||
do 200 i=1,nv4
|
||||
c1(i) = dr11+dr12*cosi(1,i)+dr13*cosi(2,i)
|
||||
200 continue
|
||||
do 210 i=1,mv
|
||||
number = nrv(i)
|
||||
fac = 0.
|
||||
do 205 j=1,4
|
||||
number = number+1
|
||||
fac = fac+c1(number)*spv(i,j)
|
||||
205 continue
|
||||
a1(2,i) = fac
|
||||
210 continue
|
||||
if(nv8.eq.0 .or. p.le.0.) go to 225
|
||||
do 220 i=1,nv8
|
||||
number = i
|
||||
fac = 0.
|
||||
do 215 j=1,5
|
||||
fac = fac+c1(number)*bv(i,j)
|
||||
number = number+1
|
||||
215 continue
|
||||
b1(2,i) = fac*pinv
|
||||
220 continue
|
||||
mvv = mv+nv8
|
||||
c we first determine the matrices (auu) and (qq). then we reduce the
|
||||
c matrix (auu) to an unit upper triangular form (ru) using givens
|
||||
c rotations without square roots. we apply the same transformations to
|
||||
c the rows of matrix qq to obtain the mv x nuu matrix g.
|
||||
c we store matrix (ru) into au and g into q.
|
||||
225 l = mvv*nuu
|
||||
c initialization.
|
||||
sq = 0.
|
||||
if(l.eq.0) go to 245
|
||||
do 230 i=1,l
|
||||
q(i) = 0.
|
||||
230 continue
|
||||
do 240 i=1,nuu
|
||||
do 240 j=1,5
|
||||
au(i,j) = 0.
|
||||
240 continue
|
||||
l = 0
|
||||
245 nrold = 0
|
||||
n1 = nrold+1
|
||||
do 420 it=1,mu
|
||||
number = nru(it)
|
||||
c find the appropriate column of q.
|
||||
250 do 260 j=1,mvv
|
||||
right(j) = 0.
|
||||
260 continue
|
||||
if(nrold.eq.number) go to 280
|
||||
if(p.le.0.) go to 410
|
||||
c fetch a new row of matrix (bu).
|
||||
do 270 j=1,5
|
||||
h(j) = bu(n1,j)*pinv
|
||||
270 continue
|
||||
i0 = 1
|
||||
i1 = 5
|
||||
go to 310
|
||||
c fetch a new row of matrix (spu).
|
||||
280 do 290 j=1,4
|
||||
h(j) = spu(it,j)
|
||||
290 continue
|
||||
c find the appropriate column of q.
|
||||
do 300 j=1,mv
|
||||
l = l+1
|
||||
right(j) = r(l)
|
||||
300 continue
|
||||
i0 = 1
|
||||
i1 = 4
|
||||
310 j0 = n1
|
||||
j1 = nu7-number
|
||||
c take into account that we eliminate the constraints (3)
|
||||
315 if(j0-1.gt.iop0) go to 335
|
||||
fac0 = h(i0)
|
||||
do 320 j=1,mv
|
||||
right(j) = right(j)-fac0*a0(j0,j)
|
||||
320 continue
|
||||
if(mv.eq.mvv) go to 330
|
||||
j = mv
|
||||
do 325 jj=1,nv8
|
||||
j = j+1
|
||||
right(j) = right(j)-fac0*b0(j0,jj)
|
||||
325 continue
|
||||
330 j0 = j0+1
|
||||
i0 = i0+1
|
||||
go to 315
|
||||
c take into account that we eliminate the constraints (4)
|
||||
335 if(j1-1.gt.iop1) go to 360
|
||||
fac1 = h(i1)
|
||||
do 340 j=1,mv
|
||||
right(j) = right(j)-fac1*a1(j1,j)
|
||||
340 continue
|
||||
if(mv.eq.mvv) go to 350
|
||||
j = mv
|
||||
do 345 jj=1,nv8
|
||||
j = j+1
|
||||
right(j) = right(j)-fac1*b1(j1,jj)
|
||||
345 continue
|
||||
350 j1 = j1+1
|
||||
i1 = i1-1
|
||||
go to 335
|
||||
360 irot = nrold-iop0-1
|
||||
if(irot.lt.0) irot = 0
|
||||
c rotate the new row of matrix (auu) into triangle.
|
||||
if(i0.gt.i1) go to 390
|
||||
do 385 i=i0,i1
|
||||
irot = irot+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 385
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,au(irot,1),co,si)
|
||||
c apply that transformation to the rows of matrix (qq).
|
||||
iq = (irot-1)*mvv
|
||||
do 370 j=1,mvv
|
||||
iq = iq+1
|
||||
call fprota(co,si,right(j),q(iq))
|
||||
370 continue
|
||||
c apply that transformation to the columns of (auu).
|
||||
if(i.eq.i1) go to 385
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 380 j=i3,i1
|
||||
i2 = i2+1
|
||||
call fprota(co,si,h(j),au(irot,i2))
|
||||
380 continue
|
||||
385 continue
|
||||
c we update the sum of squared residuals.
|
||||
390 do 395 j=1,mvv
|
||||
sq = sq+right(j)**2
|
||||
395 continue
|
||||
if(nrold.eq.number) go to 420
|
||||
410 nrold = n1
|
||||
n1 = n1+1
|
||||
go to 250
|
||||
420 continue
|
||||
if(nuu.eq.0) go to 800
|
||||
c we determine the matrix (avv) and then we reduce her to an unit
|
||||
c upper triangular form (rv) using givens rotations without square
|
||||
c roots. we apply the same transformations to the columns of matrix
|
||||
c g to obtain the (nv-7) x (nu-6-iop0-iop1) matrix h.
|
||||
c we store matrix (rv) into av1 and av2, h into c.
|
||||
c the nv7 x nv7 triangular unit upper matrix (rv) has the form
|
||||
c | av1 ' |
|
||||
c (rv) = | ' av2 |
|
||||
c | 0 ' |
|
||||
c with (av2) a nv7 x 4 matrix and (av1) a nv11 x nv11 unit upper
|
||||
c triangular matrix of bandwidth 5.
|
||||
ncof = nuu*nv7
|
||||
c initialization.
|
||||
do 430 i=1,ncof
|
||||
c(i) = 0.
|
||||
430 continue
|
||||
do 440 i=1,nv4
|
||||
av1(i,5) = 0.
|
||||
do 440 j=1,4
|
||||
av1(i,j) = 0.
|
||||
av2(i,j) = 0.
|
||||
440 continue
|
||||
jper = 0
|
||||
nrold = 0
|
||||
do 770 it=1,mv
|
||||
number = nrv(it)
|
||||
450 if(nrold.eq.number) go to 480
|
||||
if(p.le.0.) go to 760
|
||||
c fetch a new row of matrix (bv).
|
||||
n1 = nrold+1
|
||||
do 460 j=1,5
|
||||
h(j) = bv(n1,j)*pinv
|
||||
460 continue
|
||||
c find the appropriate row of g.
|
||||
do 465 j=1,nuu
|
||||
right(j) = 0.
|
||||
465 continue
|
||||
if(mv.eq.mvv) go to 510
|
||||
l = mv+n1
|
||||
do 470 j=1,nuu
|
||||
right(j) = q(l)
|
||||
l = l+mvv
|
||||
470 continue
|
||||
go to 510
|
||||
c fetch a new row of matrix (spv)
|
||||
480 h(5) = 0.
|
||||
do 490 j=1,4
|
||||
h(j) = spv(it,j)
|
||||
490 continue
|
||||
c find the appropriate row of g.
|
||||
l = it
|
||||
do 500 j=1,nuu
|
||||
right(j) = q(l)
|
||||
l = l+mvv
|
||||
500 continue
|
||||
c test whether there are non-zero values in the new row of (avv)
|
||||
c corresponding to the b-splines n(j;v),j=nv7+1,...,nv4.
|
||||
510 if(nrold.lt.nv11) go to 710
|
||||
if(jper.ne.0) go to 550
|
||||
c initialize the matrix (av2).
|
||||
jk = nv11+1
|
||||
do 540 i=1,4
|
||||
ik = jk
|
||||
do 520 j=1,5
|
||||
if(ik.le.0) go to 530
|
||||
av2(ik,i) = av1(ik,j)
|
||||
ik = ik-1
|
||||
520 continue
|
||||
530 jk = jk+1
|
||||
540 continue
|
||||
jper = 1
|
||||
c if one of the non-zero elements of the new row corresponds to one of
|
||||
c the b-splines n(j;v),j=nv7+1,...,nv4, we take account of condition
|
||||
c (2) for setting up this row of (avv). the row is stored in h1( the
|
||||
c part with respect to av1) and h2 (the part with respect to av2).
|
||||
550 do 560 i=1,4
|
||||
h1(i) = 0.
|
||||
h2(i) = 0.
|
||||
560 continue
|
||||
h1(5) = 0.
|
||||
j = nrold-nv11
|
||||
do 600 i=1,5
|
||||
j = j+1
|
||||
l0 = j
|
||||
570 l1 = l0-4
|
||||
if(l1.le.0) go to 590
|
||||
if(l1.le.nv11) go to 580
|
||||
l0 = l1-nv11
|
||||
go to 570
|
||||
580 h1(l1) = h(i)
|
||||
go to 600
|
||||
590 h2(l0) = h2(l0) + h(i)
|
||||
600 continue
|
||||
c rotate the new row of (avv) into triangle.
|
||||
if(nv11.le.0) go to 670
|
||||
c rotations with the rows 1,2,...,nv11 of (avv).
|
||||
do 660 j=1,nv11
|
||||
piv = h1(1)
|
||||
i2 = min0(nv11-j,4)
|
||||
if(piv.eq.0.) go to 640
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,av1(j,1),co,si)
|
||||
c apply that transformation to the columns of matrix g.
|
||||
ic = j
|
||||
do 610 i=1,nuu
|
||||
call fprota(co,si,right(i),c(ic))
|
||||
ic = ic+nv7
|
||||
610 continue
|
||||
c apply that transformation to the rows of (avv) with respect to av2.
|
||||
do 620 i=1,4
|
||||
call fprota(co,si,h2(i),av2(j,i))
|
||||
620 continue
|
||||
c apply that transformation to the rows of (avv) with respect to av1.
|
||||
if(i2.eq.0) go to 670
|
||||
do 630 i=1,i2
|
||||
i1 = i+1
|
||||
call fprota(co,si,h1(i1),av1(j,i1))
|
||||
630 continue
|
||||
640 do 650 i=1,i2
|
||||
h1(i) = h1(i+1)
|
||||
650 continue
|
||||
h1(i2+1) = 0.
|
||||
660 continue
|
||||
c rotations with the rows nv11+1,...,nv7 of avv.
|
||||
670 do 700 j=1,4
|
||||
ij = nv11+j
|
||||
if(ij.le.0) go to 700
|
||||
piv = h2(j)
|
||||
if(piv.eq.0.) go to 700
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,av2(ij,j),co,si)
|
||||
c apply that transformation to the columns of matrix g.
|
||||
ic = ij
|
||||
do 680 i=1,nuu
|
||||
call fprota(co,si,right(i),c(ic))
|
||||
ic = ic+nv7
|
||||
680 continue
|
||||
if(j.eq.4) go to 700
|
||||
c apply that transformation to the rows of (avv) with respect to av2.
|
||||
j1 = j+1
|
||||
do 690 i=j1,4
|
||||
call fprota(co,si,h2(i),av2(ij,i))
|
||||
690 continue
|
||||
700 continue
|
||||
c we update the sum of squared residuals.
|
||||
do 705 i=1,nuu
|
||||
sq = sq+right(i)**2
|
||||
705 continue
|
||||
go to 750
|
||||
c rotation into triangle of the new row of (avv), in case the elements
|
||||
c corresponding to the b-splines n(j;v),j=nv7+1,...,nv4 are all zero.
|
||||
710 irot =nrold
|
||||
do 740 i=1,5
|
||||
irot = irot+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 740
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,av1(irot,1),co,si)
|
||||
c apply that transformation to the columns of matrix g.
|
||||
ic = irot
|
||||
do 720 j=1,nuu
|
||||
call fprota(co,si,right(j),c(ic))
|
||||
ic = ic+nv7
|
||||
720 continue
|
||||
c apply that transformation to the rows of (avv).
|
||||
if(i.eq.5) go to 740
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 730 j=i3,5
|
||||
i2 = i2+1
|
||||
call fprota(co,si,h(j),av1(irot,i2))
|
||||
730 continue
|
||||
740 continue
|
||||
c we update the sum of squared residuals.
|
||||
do 745 i=1,nuu
|
||||
sq = sq+right(i)**2
|
||||
745 continue
|
||||
750 if(nrold.eq.number) go to 770
|
||||
760 nrold = nrold+1
|
||||
go to 450
|
||||
770 continue
|
||||
c test whether the b-spline coefficients must be determined.
|
||||
if(iback.ne.0) return
|
||||
c backward substitution to obtain the b-spline coefficients as the
|
||||
c solution of the linear system (rv) (cr) (ru)' = h.
|
||||
c first step: solve the system (rv) (c1) = h.
|
||||
k = 1
|
||||
do 780 i=1,nuu
|
||||
call fpbacp(av1,av2,c(k),nv7,4,c(k),5,nv)
|
||||
k = k+nv7
|
||||
780 continue
|
||||
c second step: solve the system (cr) (ru)' = (c1).
|
||||
k = 0
|
||||
do 795 j=1,nv7
|
||||
k = k+1
|
||||
l = k
|
||||
do 785 i=1,nuu
|
||||
right(i) = c(l)
|
||||
l = l+nv7
|
||||
785 continue
|
||||
call fpback(au,right,nuu,5,right,nu)
|
||||
l = k
|
||||
do 790 i=1,nuu
|
||||
c(l) = right(i)
|
||||
l = l+nv7
|
||||
790 continue
|
||||
795 continue
|
||||
c calculate from the conditions (2)-(3)-(4), the remaining b-spline
|
||||
c coefficients.
|
||||
800 ncof = nu4*nv4
|
||||
j = ncof
|
||||
do 805 l=1,nv4
|
||||
q(l) = dr01
|
||||
q(j) = dr11
|
||||
j = j-1
|
||||
805 continue
|
||||
i = nv4
|
||||
j = 0
|
||||
if(iop0.eq.0) go to 815
|
||||
do 810 l=1,nv4
|
||||
i = i+1
|
||||
q(i) = c0(l)
|
||||
810 continue
|
||||
815 if(nuu.eq.0) go to 835
|
||||
do 830 l=1,nuu
|
||||
ii = i
|
||||
do 820 k=1,nv7
|
||||
i = i+1
|
||||
j = j+1
|
||||
q(i) = c(j)
|
||||
820 continue
|
||||
do 825 k=1,3
|
||||
ii = ii+1
|
||||
i = i+1
|
||||
q(i) = q(ii)
|
||||
825 continue
|
||||
830 continue
|
||||
835 if(iop1.eq.0) go to 845
|
||||
do 840 l=1,nv4
|
||||
i = i+1
|
||||
q(i) = c1(l)
|
||||
840 continue
|
||||
845 do 850 i=1,ncof
|
||||
c(i) = q(i)
|
||||
850 continue
|
||||
c calculate the quantities
|
||||
c res(i,j) = (r(i,j) - s(u(i),v(j)))**2 , i=1,2,..,mu;j=1,2,..,mv
|
||||
c fp = sumi=1,mu(sumj=1,mv(res(i,j)))
|
||||
c fpu(r) = sum''i(sumj=1,mv(res(i,j))) , r=1,2,...,nu-7
|
||||
c tu(r+3) <= u(i) <= tu(r+4)
|
||||
c fpv(r) = sumi=1,mu(sum''j(res(i,j))) , r=1,2,...,nv-7
|
||||
c tv(r+3) <= v(j) <= tv(r+4)
|
||||
fp = 0.
|
||||
do 890 i=1,nu
|
||||
fpu(i) = 0.
|
||||
890 continue
|
||||
do 900 i=1,nv
|
||||
fpv(i) = 0.
|
||||
900 continue
|
||||
ir = 0
|
||||
nroldu = 0
|
||||
c main loop for the different grid points.
|
||||
do 950 i1=1,mu
|
||||
numu = nru(i1)
|
||||
numu1 = numu+1
|
||||
nroldv = 0
|
||||
do 940 i2=1,mv
|
||||
numv = nrv(i2)
|
||||
numv1 = numv+1
|
||||
ir = ir+1
|
||||
c evaluate s(u,v) at the current grid point by making the sum of the
|
||||
c cross products of the non-zero b-splines at (u,v), multiplied with
|
||||
c the appropriate b-spline coefficients.
|
||||
term = 0.
|
||||
k1 = numu*nv4+numv
|
||||
do 920 l1=1,4
|
||||
k2 = k1
|
||||
fac = spu(i1,l1)
|
||||
do 910 l2=1,4
|
||||
k2 = k2+1
|
||||
term = term+fac*spv(i2,l2)*c(k2)
|
||||
910 continue
|
||||
k1 = k1+nv4
|
||||
920 continue
|
||||
c calculate the squared residual at the current grid point.
|
||||
term = (r(ir)-term)**2
|
||||
c adjust the different parameters.
|
||||
fp = fp+term
|
||||
fpu(numu1) = fpu(numu1)+term
|
||||
fpv(numv1) = fpv(numv1)+term
|
||||
fac = term*half
|
||||
if(numv.eq.nroldv) go to 930
|
||||
fpv(numv1) = fpv(numv1)-fac
|
||||
fpv(numv) = fpv(numv)+fac
|
||||
930 nroldv = numv
|
||||
if(numu.eq.nroldu) go to 940
|
||||
fpu(numu1) = fpu(numu1)-fac
|
||||
fpu(numu) = fpu(numu)+fac
|
||||
940 continue
|
||||
nroldu = numu
|
||||
950 continue
|
||||
return
|
||||
end
|
||||
78
cxx/fitpack/fpinst.f
Normal file
78
cxx/fitpack/fpinst.f
Normal file
@ -0,0 +1,78 @@
|
||||
recursive subroutine fpinst(iopt,t,n,c,k,x,l,tt,nn,cc,nest)
|
||||
implicit none
|
||||
c given the b-spline representation (knots t(j),j=1,2,...,n, b-spline
|
||||
c coefficients c(j),j=1,2,...,n-k-1) of a spline of degree k, fpinst
|
||||
c calculates the b-spline representation (knots tt(j),j=1,2,...,nn,
|
||||
c b-spline coefficients cc(j),j=1,2,...,nn-k-1) of the same spline if
|
||||
c an additional knot is inserted at the point x situated in the inter-
|
||||
c val t(l)<=x<t(l+1). iopt denotes whether (iopt.ne.0) or not (iopt=0)
|
||||
c the given spline is periodic. in case of a periodic spline at least
|
||||
c one of the following conditions must be fulfilled: l>2*k or l<n-2*k.
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer k,n,l,nn,iopt,nest
|
||||
real*8 x
|
||||
c ..array arguments..
|
||||
real*8 t(nest),c(nest),tt(nest),cc(nest)
|
||||
c ..local scalars..
|
||||
real*8 fac,per,one
|
||||
integer i,i1,j,k1,m,mk,nk,nk1,nl,ll
|
||||
c ..
|
||||
one = 0.1e+01
|
||||
k1 = k+1
|
||||
nk1 = n-k1
|
||||
c the new knots
|
||||
ll = l+1
|
||||
i = n
|
||||
do 10 j=ll,n
|
||||
tt(i+1) = t(i)
|
||||
i = i-1
|
||||
10 continue
|
||||
tt(ll) = x
|
||||
do 20 j=1,l
|
||||
tt(j) = t(j)
|
||||
20 continue
|
||||
c the new b-spline coefficients
|
||||
i = nk1
|
||||
do 30 j=l,nk1
|
||||
cc(i+1) = c(i)
|
||||
i = i-1
|
||||
30 continue
|
||||
i = l
|
||||
do 40 j=1,k
|
||||
m = i+k1
|
||||
fac = (x-tt(i))/(tt(m)-tt(i))
|
||||
i1 = i-1
|
||||
cc(i) = fac*c(i)+(one-fac)*c(i1)
|
||||
i = i1
|
||||
40 continue
|
||||
do 50 j=1,i
|
||||
cc(j) = c(j)
|
||||
50 continue
|
||||
nn = n+1
|
||||
if(iopt.eq.0) return
|
||||
c incorporate the boundary conditions for a periodic spline.
|
||||
nk = nn-k
|
||||
nl = nk-k1
|
||||
per = tt(nk)-tt(k1)
|
||||
i = k1
|
||||
j = nk
|
||||
if(ll.le.nl) go to 70
|
||||
do 60 m=1,k
|
||||
mk = m+nl
|
||||
cc(m) = cc(mk)
|
||||
i = i-1
|
||||
j = j-1
|
||||
tt(i) = tt(j)-per
|
||||
60 continue
|
||||
return
|
||||
70 if(ll.gt.(k1+k)) return
|
||||
do 80 m=1,k
|
||||
mk = m+nl
|
||||
cc(mk) = cc(m)
|
||||
i = i+1
|
||||
j = j+1
|
||||
tt(j) = tt(i)+per
|
||||
80 continue
|
||||
return
|
||||
end
|
||||
131
cxx/fitpack/fpintb.f
Normal file
131
cxx/fitpack/fpintb.f
Normal file
@ -0,0 +1,131 @@
|
||||
recursive subroutine fpintb(t,n,bint,nk1,x,y)
|
||||
implicit none
|
||||
c subroutine fpintb calculates integrals of the normalized b-splines
|
||||
c nj,k+1(x) of degree k, defined on the set of knots t(j),j=1,2,...n.
|
||||
c it makes use of the formulae of gaffney for the calculation of
|
||||
c indefinite integrals of b-splines.
|
||||
c
|
||||
c calling sequence:
|
||||
c call fpintb(t,n,bint,nk1,x,y)
|
||||
c
|
||||
c input parameters:
|
||||
c t : real array,length n, containing the position of the knots.
|
||||
c n : integer value, giving the number of knots.
|
||||
c nk1 : integer value, giving the number of b-splines of degree k,
|
||||
c defined on the set of knots ,i.e. nk1 = n-k-1.
|
||||
c x,y : real values, containing the end points of the integration
|
||||
c interval.
|
||||
c output parameter:
|
||||
c bint : array,length nk1, containing the integrals of the b-splines.
|
||||
c ..
|
||||
c ..scalars arguments..
|
||||
integer n,nk1
|
||||
real*8 x,y
|
||||
c ..array arguments..
|
||||
real*8 t(n),bint(nk1)
|
||||
c ..local scalars..
|
||||
integer i,ia,ib,it,j,j1,k,k1,l,li,lj,lk,l0,min
|
||||
real*8 a,ak,arg,b,f,one
|
||||
c ..local arrays..
|
||||
real*8 aint(6),h(6),h1(6)
|
||||
c initialization.
|
||||
one = 0.1d+01
|
||||
k1 = n-nk1
|
||||
ak = k1
|
||||
k = k1-1
|
||||
do 10 i=1,nk1
|
||||
bint(i) = 0.0d0
|
||||
10 continue
|
||||
c the integration limits are arranged in increasing order.
|
||||
a = x
|
||||
b = y
|
||||
min = 0
|
||||
if (a.lt.b) go to 30
|
||||
if (a.eq.b) go to 160
|
||||
go to 20
|
||||
20 a = y
|
||||
b = x
|
||||
min = 1
|
||||
30 if(a.lt.t(k1)) a = t(k1)
|
||||
if(b.gt.t(nk1+1)) b = t(nk1+1)
|
||||
if(a.gt.b) go to 160
|
||||
c using the expression of gaffney for the indefinite integral of a
|
||||
c b-spline we find that
|
||||
c bint(j) = (t(j+k+1)-t(j))*(res(j,b)-res(j,a))/(k+1)
|
||||
c where for t(l) <= x < t(l+1)
|
||||
c res(j,x) = 0, j=1,2,...,l-k-1
|
||||
c = 1, j=l+1,l+2,...,nk1
|
||||
c = aint(j+k-l+1), j=l-k,l-k+1,...,l
|
||||
c = sumi((x-t(j+i))*nj+i,k+1-i(x)/(t(j+k+1)-t(j+i)))
|
||||
c i=0,1,...,k
|
||||
l = k1
|
||||
l0 = l+1
|
||||
c set arg = a.
|
||||
arg = a
|
||||
do 90 it=1,2
|
||||
c search for the knot interval t(l) <= arg < t(l+1).
|
||||
40 if(arg.lt.t(l0) .or. l.eq.nk1) go to 50
|
||||
l = l0
|
||||
l0 = l+1
|
||||
go to 40
|
||||
c calculation of aint(j), j=1,2,...,k+1.
|
||||
c initialization.
|
||||
50 do 55 j=1,k1
|
||||
aint(j) = 0.0d0
|
||||
55 continue
|
||||
aint(1) = (arg-t(l))/(t(l+1)-t(l))
|
||||
h1(1) = one
|
||||
do 70 j=1,k
|
||||
c evaluation of the non-zero b-splines of degree j at arg,i.e.
|
||||
c h(i+1) = nl-j+i,j(arg), i=0,1,...,j.
|
||||
h(1) = 0.0d0
|
||||
do 60 i=1,j
|
||||
li = l+i
|
||||
lj = li-j
|
||||
f = h1(i)/(t(li)-t(lj))
|
||||
h(i) = h(i)+f*(t(li)-arg)
|
||||
h(i+1) = f*(arg-t(lj))
|
||||
60 continue
|
||||
c updating of the integrals aint.
|
||||
j1 = j+1
|
||||
do 70 i=1,j1
|
||||
li = l+i
|
||||
lj = li-j1
|
||||
aint(i) = aint(i)+h(i)*(arg-t(lj))/(t(li)-t(lj))
|
||||
h1(i) = h(i)
|
||||
70 continue
|
||||
if(it.eq.2) go to 100
|
||||
c updating of the integrals bint
|
||||
lk = l-k
|
||||
ia = lk
|
||||
do 80 i=1,k1
|
||||
bint(lk) = -aint(i)
|
||||
lk = lk+1
|
||||
80 continue
|
||||
c set arg = b.
|
||||
arg = b
|
||||
90 continue
|
||||
c updating of the integrals bint.
|
||||
100 lk = l-k
|
||||
ib = lk-1
|
||||
do 110 i=1,k1
|
||||
bint(lk) = bint(lk)+aint(i)
|
||||
lk = lk+1
|
||||
110 continue
|
||||
if(ib.lt.ia) go to 130
|
||||
do 120 i=ia,ib
|
||||
bint(i) = bint(i)+one
|
||||
120 continue
|
||||
c the scaling factors are taken into account.
|
||||
130 f = one/ak
|
||||
do 140 i=1,nk1
|
||||
j = i+k1
|
||||
bint(i) = bint(i)*(t(j)-t(i))*f
|
||||
140 continue
|
||||
c the order of the integration limits is taken into account.
|
||||
if(min.eq.0) go to 160
|
||||
do 150 i=1,nk1
|
||||
bint(i) = -bint(i)
|
||||
150 continue
|
||||
160 return
|
||||
end
|
||||
73
cxx/fitpack/fpknot.f
Normal file
73
cxx/fitpack/fpknot.f
Normal file
@ -0,0 +1,73 @@
|
||||
recursive subroutine fpknot(x,m,t,n,fpint,nrdata,nrint,nest,
|
||||
* istart)
|
||||
implicit none
|
||||
c subroutine fpknot locates an additional knot for a spline of degree
|
||||
c k and adjusts the corresponding parameters,i.e.
|
||||
c t : the position of the knots.
|
||||
c n : the number of knots.
|
||||
c nrint : the number of knotintervals.
|
||||
c fpint : the sum of squares of residual right hand sides
|
||||
c for each knot interval.
|
||||
c nrdata: the number of data points inside each knot interval.
|
||||
c istart indicates that the smallest data point at which the new knot
|
||||
c may be added is x(istart+1)
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer m,n,nrint,nest,istart
|
||||
c ..array arguments..
|
||||
real*8 x(m),t(nest),fpint(nest)
|
||||
integer nrdata(nest)
|
||||
c ..local scalars..
|
||||
real*8 an,am,fpmax
|
||||
integer ihalf,j,jbegin,jj,jk,jpoint,k,maxbeg,maxpt,
|
||||
* next,nrx,number
|
||||
|
||||
c note: do not initialize on the same line to avoid saving between calls
|
||||
logical iserr
|
||||
iserr = .TRUE.
|
||||
|
||||
k = (n-nrint-1)/2
|
||||
c search for knot interval t(number+k) <= x <= t(number+k+1) where
|
||||
c fpint(number) is maximal on the condition that nrdata(number)
|
||||
c not equals zero.
|
||||
fpmax = 0.
|
||||
jbegin = istart
|
||||
do 20 j=1,nrint
|
||||
jpoint = nrdata(j)
|
||||
if(fpmax.ge.fpint(j) .or. jpoint.eq.0) go to 10
|
||||
iserr = .FALSE.
|
||||
fpmax = fpint(j)
|
||||
number = j
|
||||
maxpt = jpoint
|
||||
maxbeg = jbegin
|
||||
10 jbegin = jbegin+jpoint+1
|
||||
20 continue
|
||||
c error condition detected, go to exit
|
||||
if(iserr) go to 50
|
||||
c let coincide the new knot t(number+k+1) with a data point x(nrx)
|
||||
c inside the old knot interval t(number+k) <= x <= t(number+k+1).
|
||||
ihalf = maxpt/2+1
|
||||
nrx = maxbeg+ihalf
|
||||
next = number+1
|
||||
if(next.gt.nrint) go to 40
|
||||
c adjust the different parameters.
|
||||
do 30 j=next,nrint
|
||||
jj = next+nrint-j
|
||||
fpint(jj+1) = fpint(jj)
|
||||
nrdata(jj+1) = nrdata(jj)
|
||||
jk = jj+k
|
||||
t(jk+1) = t(jk)
|
||||
30 continue
|
||||
40 nrdata(number) = ihalf-1
|
||||
nrdata(next) = maxpt-ihalf
|
||||
am = maxpt
|
||||
an = nrdata(number)
|
||||
fpint(number) = fpmax*an/am
|
||||
an = nrdata(next)
|
||||
fpint(next) = fpmax*an/am
|
||||
jk = next+k
|
||||
t(jk) = x(nrx)
|
||||
50 n = n+1
|
||||
nrint = nrint+1
|
||||
return
|
||||
end
|
||||
182
cxx/fitpack/fpopdi.f
Normal file
182
cxx/fitpack/fpopdi.f
Normal file
@ -0,0 +1,182 @@
|
||||
recursive subroutine fpopdi(ifsu,ifsv,ifbu,ifbv,u,mu,v,mv,z,
|
||||
* mz,z0,dz,iopt,ider,tu,nu,tv,nv,nuest,nvest,p,step,c,nc,fp,
|
||||
* fpu,fpv,nru,nrv,wrk,lwrk)
|
||||
implicit none
|
||||
c given the set of function values z(i,j) defined on the rectangular
|
||||
c grid (u(i),v(j)),i=1,2,...,mu;j=1,2,...,mv, fpopdi determines a
|
||||
c smooth bicubic spline approximation with given knots tu(i),i=1,..,nu
|
||||
c in the u-direction and tv(j),j=1,2,...,nv in the v-direction. this
|
||||
c spline sp(u,v) will be periodic in the variable v and will satisfy
|
||||
c the following constraints
|
||||
c
|
||||
c s(tu(1),v) = dz(1) , tv(4) <=v<= tv(nv-3)
|
||||
c
|
||||
c and (if iopt(2) = 1)
|
||||
c
|
||||
c d s(tu(1),v)
|
||||
c ------------ = dz(2)*cos(v)+dz(3)*sin(v) , tv(4) <=v<= tv(nv-3)
|
||||
c d u
|
||||
c
|
||||
c and (if iopt(3) = 1)
|
||||
c
|
||||
c s(tu(nu),v) = 0 tv(4) <=v<= tv(nv-3)
|
||||
c
|
||||
c where the parameters dz(i) correspond to the derivative values g(i,j)
|
||||
c as defined in subroutine pogrid.
|
||||
c
|
||||
c the b-spline coefficients of sp(u,v) are determined as the least-
|
||||
c squares solution of an overdetermined linear system which depends
|
||||
c on the value of p and on the values dz(i),i=1,2,3. the correspond-
|
||||
c ing sum of squared residuals sq is a simple quadratic function in
|
||||
c the variables dz(i). these may or may not be provided. the values
|
||||
c dz(i) which are not given will be determined so as to minimize the
|
||||
c resulting sum of squared residuals sq. in that case the user must
|
||||
c provide some initial guess dz(i) and some estimate (dz(i)-step,
|
||||
c dz(i)+step) of the range of possible values for these latter.
|
||||
c
|
||||
c sp(u,v) also depends on the parameter p (p>0) in such a way that
|
||||
c - if p tends to infinity, sp(u,v) becomes the least-squares spline
|
||||
c with given knots, satisfying the constraints.
|
||||
c - if p tends to zero, sp(u,v) becomes the least-squares polynomial,
|
||||
c satisfying the constraints.
|
||||
c - the function f(p)=sumi=1,mu(sumj=1,mv((z(i,j)-sp(u(i),v(j)))**2)
|
||||
c is continuous and strictly decreasing for p>0.
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer ifsu,ifsv,ifbu,ifbv,mu,mv,mz,nu,nv,nuest,nvest,
|
||||
* nc,lwrk
|
||||
real*8 z0,p,step,fp
|
||||
c ..array arguments..
|
||||
integer ider(2),nru(mu),nrv(mv),iopt(3)
|
||||
real*8 u(mu),v(mv),z(mz),dz(3),tu(nu),tv(nv),c(nc),fpu(nu),fpv(nv)
|
||||
*,
|
||||
* wrk(lwrk)
|
||||
c ..local scalars..
|
||||
real*8 res,sq,sqq,step1,step2,three
|
||||
integer i,id0,iop0,iop1,i1,j,l,laa,lau,lav1,lav2,lbb,lbu,lbv,
|
||||
* lcc,lcs,lq,lri,lsu,lsv,l1,l2,mm,mvnu,number
|
||||
c ..local arrays..
|
||||
integer nr(3)
|
||||
real*8 delta(3),dzz(3),sum(3),a(6,6),g(6)
|
||||
c ..function references..
|
||||
integer max0
|
||||
c ..subroutine references..
|
||||
c fpgrdi,fpsysy
|
||||
c ..
|
||||
c set constant
|
||||
three = 3
|
||||
c we partition the working space
|
||||
lsu = 1
|
||||
lsv = lsu+4*mu
|
||||
lri = lsv+4*mv
|
||||
mm = max0(nuest,mv+nvest)
|
||||
lq = lri+mm
|
||||
mvnu = nuest*(mv+nvest-8)
|
||||
lau = lq+mvnu
|
||||
lav1 = lau+5*nuest
|
||||
lav2 = lav1+6*nvest
|
||||
lbu = lav2+4*nvest
|
||||
lbv = lbu+5*nuest
|
||||
laa = lbv+5*nvest
|
||||
lbb = laa+2*mv
|
||||
lcc = lbb+2*nvest
|
||||
lcs = lcc+nvest
|
||||
c we calculate the smoothing spline sp(u,v) according to the input
|
||||
c values dz(i),i=1,2,3.
|
||||
iop0 = iopt(2)
|
||||
iop1 = iopt(3)
|
||||
call fpgrdi(ifsu,ifsv,ifbu,ifbv,0,u,mu,v,mv,z,mz,dz,
|
||||
* iop0,iop1,tu,nu,tv,nv,p,c,nc,sq,fp,fpu,fpv,mm,mvnu,
|
||||
* wrk(lsu),wrk(lsv),wrk(lri),wrk(lq),wrk(lau),wrk(lav1),
|
||||
* wrk(lav2),wrk(lbu),wrk(lbv),wrk(laa),wrk(lbb),
|
||||
* wrk(lcc),wrk(lcs),nru,nrv)
|
||||
id0 = ider(1)
|
||||
if(id0.ne.0) go to 5
|
||||
res = (z0-dz(1))**2
|
||||
fp = fp+res
|
||||
sq = sq+res
|
||||
c in case all derivative values dz(i) are given (step<=0) or in case
|
||||
c we have spline interpolation, we accept this spline as a solution.
|
||||
5 if(step.le.0. .or. sq.le.0.) return
|
||||
dzz(1) = dz(1)
|
||||
dzz(2) = dz(2)
|
||||
dzz(3) = dz(3)
|
||||
c number denotes the number of derivative values dz(i) that still must
|
||||
c be optimized. let us denote these parameters by g(j),j=1,...,number.
|
||||
number = 0
|
||||
if(id0.gt.0) go to 10
|
||||
number = 1
|
||||
nr(1) = 1
|
||||
delta(1) = step
|
||||
10 if(iop0.eq.0) go to 20
|
||||
if(ider(2).ne.0) go to 20
|
||||
step2 = step*three/tu(5)
|
||||
nr(number+1) = 2
|
||||
nr(number+2) = 3
|
||||
delta(number+1) = step2
|
||||
delta(number+2) = step2
|
||||
number = number+2
|
||||
20 if(number.eq.0) return
|
||||
c the sum of squared residuals sq is a quadratic polynomial in the
|
||||
c parameters g(j). we determine the unknown coefficients of this
|
||||
c polymomial by calculating (number+1)*(number+2)/2 different splines
|
||||
c according to specific values for g(j).
|
||||
do 30 i=1,number
|
||||
l = nr(i)
|
||||
step1 = delta(i)
|
||||
dzz(l) = dz(l)+step1
|
||||
call fpgrdi(ifsu,ifsv,ifbu,ifbv,1,u,mu,v,mv,z,mz,dzz,
|
||||
* iop0,iop1,tu,nu,tv,nv,p,c,nc,sum(i),fp,fpu,fpv,mm,mvnu,
|
||||
* wrk(lsu),wrk(lsv),wrk(lri),wrk(lq),wrk(lau),wrk(lav1),
|
||||
* wrk(lav2),wrk(lbu),wrk(lbv),wrk(laa),wrk(lbb),
|
||||
* wrk(lcc),wrk(lcs),nru,nrv)
|
||||
if(id0.eq.0) sum(i) = sum(i)+(z0-dzz(1))**2
|
||||
dzz(l) = dz(l)-step1
|
||||
call fpgrdi(ifsu,ifsv,ifbu,ifbv,1,u,mu,v,mv,z,mz,dzz,
|
||||
* iop0,iop1,tu,nu,tv,nv,p,c,nc,sqq,fp,fpu,fpv,mm,mvnu,
|
||||
* wrk(lsu),wrk(lsv),wrk(lri),wrk(lq),wrk(lau),wrk(lav1),
|
||||
* wrk(lav2),wrk(lbu),wrk(lbv),wrk(laa),wrk(lbb),
|
||||
* wrk(lcc),wrk(lcs),nru,nrv)
|
||||
if(id0.eq.0) sqq = sqq+(z0-dzz(1))**2
|
||||
a(i,i) = (sum(i)+sqq-sq-sq)/step1**2
|
||||
if(a(i,i).le.0.) go to 80
|
||||
g(i) = (sqq-sum(i))/(step1+step1)
|
||||
dzz(l) = dz(l)
|
||||
30 continue
|
||||
if(number.eq.1) go to 60
|
||||
do 50 i=2,number
|
||||
l1 = nr(i)
|
||||
step1 = delta(i)
|
||||
dzz(l1) = dz(l1)+step1
|
||||
i1 = i-1
|
||||
do 40 j=1,i1
|
||||
l2 = nr(j)
|
||||
step2 = delta(j)
|
||||
dzz(l2) = dz(l2)+step2
|
||||
call fpgrdi(ifsu,ifsv,ifbu,ifbv,1,u,mu,v,mv,z,mz,dzz,
|
||||
* iop0,iop1,tu,nu,tv,nv,p,c,nc,sqq,fp,fpu,fpv,mm,mvnu,
|
||||
* wrk(lsu),wrk(lsv),wrk(lri),wrk(lq),wrk(lau),wrk(lav1),
|
||||
* wrk(lav2),wrk(lbu),wrk(lbv),wrk(laa),wrk(lbb),
|
||||
* wrk(lcc),wrk(lcs),nru,nrv)
|
||||
if(id0.eq.0) sqq = sqq+(z0-dzz(1))**2
|
||||
a(i,j) = (sq+sqq-sum(i)-sum(j))/(step1*step2)
|
||||
dzz(l2) = dz(l2)
|
||||
40 continue
|
||||
dzz(l1) = dz(l1)
|
||||
50 continue
|
||||
c the optimal values g(j) are found as the solution of the system
|
||||
c d (sq) / d (g(j)) = 0 , j=1,...,number.
|
||||
60 call fpsysy(a,number,g)
|
||||
do 70 i=1,number
|
||||
l = nr(i)
|
||||
dz(l) = dz(l)+g(i)
|
||||
70 continue
|
||||
c we determine the spline sp(u,v) according to the optimal values g(j).
|
||||
80 call fpgrdi(ifsu,ifsv,ifbu,ifbv,0,u,mu,v,mv,z,mz,dz,
|
||||
* iop0,iop1,tu,nu,tv,nv,p,c,nc,sq,fp,fpu,fpv,mm,mvnu,
|
||||
* wrk(lsu),wrk(lsv),wrk(lri),wrk(lq),wrk(lau),wrk(lav1),
|
||||
* wrk(lav2),wrk(lbu),wrk(lbv),wrk(laa),wrk(lbb),
|
||||
* wrk(lcc),wrk(lcs),nru,nrv)
|
||||
if(id0.eq.0) fp = fp+(z0-dz(1))**2
|
||||
return
|
||||
end
|
||||
212
cxx/fitpack/fpopsp.f
Normal file
212
cxx/fitpack/fpopsp.f
Normal file
@ -0,0 +1,212 @@
|
||||
recursive subroutine fpopsp(ifsu,ifsv,ifbu,ifbv,u,mu,v,mv,r,
|
||||
* mr,r0,r1,dr,iopt,ider,tu,nu,tv,nv,nuest,nvest,p,step,c,nc,
|
||||
* fp,fpu,fpv,nru,nrv,wrk,lwrk)
|
||||
implicit none
|
||||
c given the set of function values r(i,j) defined on the rectangular
|
||||
c grid (u(i),v(j)),i=1,2,...,mu;j=1,2,...,mv, fpopsp determines a
|
||||
c smooth bicubic spline approximation with given knots tu(i),i=1,..,nu
|
||||
c in the u-direction and tv(j),j=1,2,...,nv in the v-direction. this
|
||||
c spline sp(u,v) will be periodic in the variable v and will satisfy
|
||||
c the following constraints
|
||||
c
|
||||
c s(tu(1),v) = dr(1) , tv(4) <=v<= tv(nv-3)
|
||||
c
|
||||
c s(tu(nu),v) = dr(4) , tv(4) <=v<= tv(nv-3)
|
||||
c
|
||||
c and (if iopt(2) = 1)
|
||||
c
|
||||
c d s(tu(1),v)
|
||||
c ------------ = dr(2)*cos(v)+dr(3)*sin(v) , tv(4) <=v<= tv(nv-3)
|
||||
c d u
|
||||
c
|
||||
c and (if iopt(3) = 1)
|
||||
c
|
||||
c d s(tu(nu),v)
|
||||
c ------------- = dr(5)*cos(v)+dr(6)*sin(v) , tv(4) <=v<= tv(nv-3)
|
||||
c d u
|
||||
c
|
||||
c where the parameters dr(i) correspond to the derivative values at the
|
||||
c poles as defined in subroutine spgrid.
|
||||
c
|
||||
c the b-spline coefficients of sp(u,v) are determined as the least-
|
||||
c squares solution of an overdetermined linear system which depends
|
||||
c on the value of p and on the values dr(i),i=1,...,6. the correspond-
|
||||
c ing sum of squared residuals sq is a simple quadratic function in
|
||||
c the variables dr(i). these may or may not be provided. the values
|
||||
c dr(i) which are not given will be determined so as to minimize the
|
||||
c resulting sum of squared residuals sq. in that case the user must
|
||||
c provide some initial guess dr(i) and some estimate (dr(i)-step,
|
||||
c dr(i)+step) of the range of possible values for these latter.
|
||||
c
|
||||
c sp(u,v) also depends on the parameter p (p>0) in such a way that
|
||||
c - if p tends to infinity, sp(u,v) becomes the least-squares spline
|
||||
c with given knots, satisfying the constraints.
|
||||
c - if p tends to zero, sp(u,v) becomes the least-squares polynomial,
|
||||
c satisfying the constraints.
|
||||
c - the function f(p)=sumi=1,mu(sumj=1,mv((r(i,j)-sp(u(i),v(j)))**2)
|
||||
c is continuous and strictly decreasing for p>0.
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer ifsu,ifsv,ifbu,ifbv,mu,mv,mr,nu,nv,nuest,nvest,
|
||||
* nc,lwrk
|
||||
real*8 r0,r1,p,fp
|
||||
c ..array arguments..
|
||||
integer ider(4),nru(mu),nrv(mv),iopt(3)
|
||||
real*8 u(mu),v(mv),r(mr),dr(6),tu(nu),tv(nv),c(nc),fpu(nu),fpv(nv)
|
||||
*,
|
||||
* wrk(lwrk),step(2)
|
||||
c ..local scalars..
|
||||
real*8 sq,sqq,sq0,sq1,step1,step2,three
|
||||
integer i,id0,iop0,iop1,i1,j,l,lau,lav1,lav2,la0,la1,lbu,lbv,lb0,
|
||||
* lb1,lc0,lc1,lcs,lq,lri,lsu,lsv,l1,l2,mm,mvnu,number, id1
|
||||
c ..local arrays..
|
||||
integer nr(6)
|
||||
real*8 delta(6),drr(6),sum(6),a(6,6),g(6)
|
||||
c ..function references..
|
||||
integer max0
|
||||
c ..subroutine references..
|
||||
c fpgrsp,fpsysy
|
||||
c ..
|
||||
c set constant
|
||||
three = 3
|
||||
c we partition the working space
|
||||
lsu = 1
|
||||
lsv = lsu+4*mu
|
||||
lri = lsv+4*mv
|
||||
mm = max0(nuest,mv+nvest)
|
||||
lq = lri+mm
|
||||
mvnu = nuest*(mv+nvest-8)
|
||||
lau = lq+mvnu
|
||||
lav1 = lau+5*nuest
|
||||
lav2 = lav1+6*nvest
|
||||
lbu = lav2+4*nvest
|
||||
lbv = lbu+5*nuest
|
||||
la0 = lbv+5*nvest
|
||||
la1 = la0+2*mv
|
||||
lb0 = la1+2*mv
|
||||
lb1 = lb0+2*nvest
|
||||
lc0 = lb1+2*nvest
|
||||
lc1 = lc0+nvest
|
||||
lcs = lc1+nvest
|
||||
c we calculate the smoothing spline sp(u,v) according to the input
|
||||
c values dr(i),i=1,...,6.
|
||||
iop0 = iopt(2)
|
||||
iop1 = iopt(3)
|
||||
id0 = ider(1)
|
||||
id1 = ider(3)
|
||||
call fpgrsp(ifsu,ifsv,ifbu,ifbv,0,u,mu,v,mv,r,mr,dr,
|
||||
* iop0,iop1,tu,nu,tv,nv,p,c,nc,sq,fp,fpu,fpv,mm,mvnu,
|
||||
* wrk(lsu),wrk(lsv),wrk(lri),wrk(lq),wrk(lau),wrk(lav1),
|
||||
* wrk(lav2),wrk(lbu),wrk(lbv),wrk(la0),wrk(la1),wrk(lb0),
|
||||
* wrk(lb1),wrk(lc0),wrk(lc1),wrk(lcs),nru,nrv)
|
||||
sq0 = 0.
|
||||
sq1 = 0.
|
||||
if(id0.eq.0) sq0 = (r0-dr(1))**2
|
||||
if(id1.eq.0) sq1 = (r1-dr(4))**2
|
||||
sq = sq+sq0+sq1
|
||||
c in case all derivative values dr(i) are given (step<=0) or in case
|
||||
c we have spline interpolation, we accept this spline as a solution.
|
||||
if(sq.le.0.) return
|
||||
if(step(1).le.0. .and. step(2).le.0.) return
|
||||
do 10 i=1,6
|
||||
drr(i) = dr(i)
|
||||
10 continue
|
||||
c number denotes the number of derivative values dr(i) that still must
|
||||
c be optimized. let us denote these parameters by g(j),j=1,...,number.
|
||||
number = 0
|
||||
if(id0.gt.0) go to 20
|
||||
number = 1
|
||||
nr(1) = 1
|
||||
delta(1) = step(1)
|
||||
20 if(iop0.eq.0) go to 30
|
||||
if(ider(2).ne.0) go to 30
|
||||
step2 = step(1)*three/(tu(5)-tu(4))
|
||||
nr(number+1) = 2
|
||||
nr(number+2) = 3
|
||||
delta(number+1) = step2
|
||||
delta(number+2) = step2
|
||||
number = number+2
|
||||
30 if(id1.gt.0) go to 40
|
||||
number = number+1
|
||||
nr(number) = 4
|
||||
delta(number) = step(2)
|
||||
40 if(iop1.eq.0) go to 50
|
||||
if(ider(4).ne.0) go to 50
|
||||
step2 = step(2)*three/(tu(nu)-tu(nu-4))
|
||||
nr(number+1) = 5
|
||||
nr(number+2) = 6
|
||||
delta(number+1) = step2
|
||||
delta(number+2) = step2
|
||||
number = number+2
|
||||
50 if(number.eq.0) return
|
||||
c the sum of squared residulas sq is a quadratic polynomial in the
|
||||
c parameters g(j). we determine the unknown coefficients of this
|
||||
c polymomial by calculating (number+1)*(number+2)/2 different splines
|
||||
c according to specific values for g(j).
|
||||
do 60 i=1,number
|
||||
l = nr(i)
|
||||
step1 = delta(i)
|
||||
drr(l) = dr(l)+step1
|
||||
call fpgrsp(ifsu,ifsv,ifbu,ifbv,1,u,mu,v,mv,r,mr,drr,
|
||||
* iop0,iop1,tu,nu,tv,nv,p,c,nc,sum(i),fp,fpu,fpv,mm,mvnu,
|
||||
* wrk(lsu),wrk(lsv),wrk(lri),wrk(lq),wrk(lau),wrk(lav1),
|
||||
* wrk(lav2),wrk(lbu),wrk(lbv),wrk(la0),wrk(la1),wrk(lb0),
|
||||
* wrk(lb1),wrk(lc0),wrk(lc1),wrk(lcs),nru,nrv)
|
||||
if(id0.eq.0) sq0 = (r0-drr(1))**2
|
||||
if(id1.eq.0) sq1 = (r1-drr(4))**2
|
||||
sum(i) = sum(i)+sq0+sq1
|
||||
drr(l) = dr(l)-step1
|
||||
call fpgrsp(ifsu,ifsv,ifbu,ifbv,1,u,mu,v,mv,r,mr,drr,
|
||||
* iop0,iop1,tu,nu,tv,nv,p,c,nc,sqq,fp,fpu,fpv,mm,mvnu,
|
||||
* wrk(lsu),wrk(lsv),wrk(lri),wrk(lq),wrk(lau),wrk(lav1),
|
||||
* wrk(lav2),wrk(lbu),wrk(lbv),wrk(la0),wrk(la1),wrk(lb0),
|
||||
* wrk(lb1),wrk(lc0),wrk(lc1),wrk(lcs),nru,nrv)
|
||||
if(id0.eq.0) sq0 = (r0-drr(1))**2
|
||||
if(id1.eq.0) sq1 = (r1-drr(4))**2
|
||||
sqq = sqq+sq0+sq1
|
||||
drr(l) = dr(l)
|
||||
a(i,i) = (sum(i)+sqq-sq-sq)/step1**2
|
||||
if(a(i,i).le.0.) go to 110
|
||||
g(i) = (sqq-sum(i))/(step1+step1)
|
||||
60 continue
|
||||
if(number.eq.1) go to 90
|
||||
do 80 i=2,number
|
||||
l1 = nr(i)
|
||||
step1 = delta(i)
|
||||
drr(l1) = dr(l1)+step1
|
||||
i1 = i-1
|
||||
do 70 j=1,i1
|
||||
l2 = nr(j)
|
||||
step2 = delta(j)
|
||||
drr(l2) = dr(l2)+step2
|
||||
call fpgrsp(ifsu,ifsv,ifbu,ifbv,1,u,mu,v,mv,r,mr,drr,
|
||||
* iop0,iop1,tu,nu,tv,nv,p,c,nc,sqq,fp,fpu,fpv,mm,mvnu,
|
||||
* wrk(lsu),wrk(lsv),wrk(lri),wrk(lq),wrk(lau),wrk(lav1),
|
||||
* wrk(lav2),wrk(lbu),wrk(lbv),wrk(la0),wrk(la1),wrk(lb0),
|
||||
* wrk(lb1),wrk(lc0),wrk(lc1),wrk(lcs),nru,nrv)
|
||||
if(id0.eq.0) sq0 = (r0-drr(1))**2
|
||||
if(id1.eq.0) sq1 = (r1-drr(4))**2
|
||||
sqq = sqq+sq0+sq1
|
||||
a(i,j) = (sq+sqq-sum(i)-sum(j))/(step1*step2)
|
||||
drr(l2) = dr(l2)
|
||||
70 continue
|
||||
drr(l1) = dr(l1)
|
||||
80 continue
|
||||
c the optimal values g(j) are found as the solution of the system
|
||||
c d (sq) / d (g(j)) = 0 , j=1,...,number.
|
||||
90 call fpsysy(a,number,g)
|
||||
do 100 i=1,number
|
||||
l = nr(i)
|
||||
dr(l) = dr(l)+g(i)
|
||||
100 continue
|
||||
c we determine the spline sp(u,v) according to the optimal values g(j).
|
||||
110 call fpgrsp(ifsu,ifsv,ifbu,ifbv,0,u,mu,v,mv,r,mr,dr,
|
||||
* iop0,iop1,tu,nu,tv,nv,p,c,nc,sq,fp,fpu,fpv,mm,mvnu,
|
||||
* wrk(lsu),wrk(lsv),wrk(lri),wrk(lq),wrk(lau),wrk(lav1),
|
||||
* wrk(lav2),wrk(lbu),wrk(lbv),wrk(la0),wrk(la1),wrk(lb0),
|
||||
* wrk(lb1),wrk(lc0),wrk(lc1),wrk(lcs),nru,nrv)
|
||||
if(id0.eq.0) sq0 = (r0-dr(1))**2
|
||||
if(id1.eq.0) sq1 = (r1-dr(4))**2
|
||||
sq = sq+sq0+sq1
|
||||
return
|
||||
end
|
||||
48
cxx/fitpack/fporde.f
Normal file
48
cxx/fitpack/fporde.f
Normal file
@ -0,0 +1,48 @@
|
||||
recursive subroutine fporde(x,y,m,kx,ky,tx,nx,ty,ny,nummer,
|
||||
* index,nreg)
|
||||
c subroutine fporde sorts the data points (x(i),y(i)),i=1,2,...,m
|
||||
c according to the panel tx(l)<=x<tx(l+1),ty(k)<=y<ty(k+1), they belong
|
||||
c to. for each panel a stack is constructed containing the numbers
|
||||
c of data points lying inside; index(j),j=1,2,...,nreg points to the
|
||||
c first data point in the jth panel while nummer(i),i=1,2,...,m gives
|
||||
c the number of the next data point in the panel.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer m,kx,ky,nx,ny,nreg
|
||||
c ..array arguments..
|
||||
real*8 x(m),y(m),tx(nx),ty(ny)
|
||||
integer nummer(m),index(nreg)
|
||||
c ..local scalars..
|
||||
real*8 xi,yi
|
||||
integer i,im,k,kx1,ky1,k1,l,l1,nk1x,nk1y,num,nyy
|
||||
c ..
|
||||
kx1 = kx+1
|
||||
ky1 = ky+1
|
||||
nk1x = nx-kx1
|
||||
nk1y = ny-ky1
|
||||
nyy = nk1y-ky
|
||||
do 10 i=1,nreg
|
||||
index(i) = 0
|
||||
10 continue
|
||||
do 60 im=1,m
|
||||
xi = x(im)
|
||||
yi = y(im)
|
||||
l = kx1
|
||||
l1 = l+1
|
||||
20 if(xi.lt.tx(l1) .or. l.eq.nk1x) go to 30
|
||||
l = l1
|
||||
l1 = l+1
|
||||
go to 20
|
||||
30 k = ky1
|
||||
k1 = k+1
|
||||
40 if(yi.lt.ty(k1) .or. k.eq.nk1y) go to 50
|
||||
k = k1
|
||||
k1 = k+1
|
||||
go to 40
|
||||
50 num = (l-kx1)*nyy+k-ky
|
||||
nummer(im) = index(num)
|
||||
index(num) = im
|
||||
60 continue
|
||||
return
|
||||
end
|
||||
|
||||
402
cxx/fitpack/fppara.f
Normal file
402
cxx/fitpack/fppara.f
Normal file
@ -0,0 +1,402 @@
|
||||
subroutine fppara(iopt,idim,m,u,mx,x,w,ub,ue,k,s,nest,tol,maxit,
|
||||
* k1,k2,n,t,nc,c,fp,fpint,z,a,b,g,q,nrdata,ier)
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 ub,ue,s,tol,fp
|
||||
integer iopt,idim,m,mx,k,nest,maxit,k1,k2,n,nc,ier
|
||||
c ..array arguments..
|
||||
real*8 u(m),x(mx),w(m),t(nest),c(nc),fpint(nest),
|
||||
* z(nc),a(nest,k1),b(nest,k2),g(nest,k2),q(m,k1)
|
||||
integer nrdata(nest)
|
||||
c ..local scalars..
|
||||
real*8 acc,con1,con4,con9,cos,fac,fpart,fpms,fpold,fp0,f1,f2,f3,
|
||||
* half,one,p,pinv,piv,p1,p2,p3,rn,sin,store,term,ui,wi
|
||||
integer i,ich1,ich3,it,iter,i1,i2,i3,j,jj,j1,j2,k3,l,l0,
|
||||
* mk1,new,nk1,nmax,nmin,nplus,npl1,nrint,n8
|
||||
c ..local arrays..
|
||||
real*8 h(7),xi(10)
|
||||
c ..function references
|
||||
real*8 abs,fprati
|
||||
integer max0,min0
|
||||
c ..subroutine references..
|
||||
c fpback,fpbspl,fpgivs,fpdisc,fpknot,fprota
|
||||
c ..
|
||||
c set constants
|
||||
one = 0.1e+01
|
||||
con1 = 0.1e0
|
||||
con9 = 0.9e0
|
||||
con4 = 0.4e-01
|
||||
half = 0.5e0
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 1: determination of the number of knots and their position c
|
||||
c ************************************************************** c
|
||||
c given a set of knots we compute the least-squares curve sinf(u), c
|
||||
c and the corresponding sum of squared residuals fp=f(p=inf). c
|
||||
c if iopt=-1 sinf(u) is the requested curve. c
|
||||
c if iopt=0 or iopt=1 we check whether we can accept the knots: c
|
||||
c if fp <=s we will continue with the current set of knots. c
|
||||
c if fp > s we will increase the number of knots and compute the c
|
||||
c corresponding least-squares curve until finally fp<=s. c
|
||||
c the initial choice of knots depends on the value of s and iopt. c
|
||||
c if s=0 we have spline interpolation; in that case the number of c
|
||||
c knots equals nmax = m+k+1. c
|
||||
c if s > 0 and c
|
||||
c iopt=0 we first compute the least-squares polynomial curve of c
|
||||
c degree k; n = nmin = 2*k+2 c
|
||||
c iopt=1 we start with the set of knots found at the last c
|
||||
c call of the routine, except for the case that s > fp0; then c
|
||||
c we compute directly the polynomial curve of degree k. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c determine nmin, the number of knots for polynomial approximation.
|
||||
nmin = 2*k1
|
||||
if(iopt.lt.0) go to 60
|
||||
c calculation of acc, the absolute tolerance for the root of f(p)=s.
|
||||
acc = tol*s
|
||||
c determine nmax, the number of knots for spline interpolation.
|
||||
nmax = m+k1
|
||||
if(s.gt.0.) go to 45
|
||||
c if s=0, s(u) is an interpolating curve.
|
||||
c test whether the required storage space exceeds the available one.
|
||||
n = nmax
|
||||
if(nmax.gt.nest) go to 420
|
||||
c find the position of the interior knots in case of interpolation.
|
||||
10 mk1 = m-k1
|
||||
if(mk1.eq.0) go to 60
|
||||
k3 = k/2
|
||||
i = k2
|
||||
j = k3+2
|
||||
if(k3*2.eq.k) go to 30
|
||||
do 20 l=1,mk1
|
||||
t(i) = u(j)
|
||||
i = i+1
|
||||
j = j+1
|
||||
20 continue
|
||||
go to 60
|
||||
30 do 40 l=1,mk1
|
||||
t(i) = (u(j)+u(j-1))*half
|
||||
i = i+1
|
||||
j = j+1
|
||||
40 continue
|
||||
go to 60
|
||||
c if s>0 our initial choice of knots depends on the value of iopt.
|
||||
c if iopt=0 or iopt=1 and s>=fp0, we start computing the least-squares
|
||||
c polynomial curve which is a spline curve without interior knots.
|
||||
c if iopt=1 and fp0>s we start computing the least squares spline curve
|
||||
c according to the set of knots found at the last call of the routine.
|
||||
45 if(iopt.eq.0) go to 50
|
||||
if(n.eq.nmin) go to 50
|
||||
fp0 = fpint(n)
|
||||
fpold = fpint(n-1)
|
||||
nplus = nrdata(n)
|
||||
if(fp0.gt.s) go to 60
|
||||
50 n = nmin
|
||||
fpold = 0.
|
||||
nplus = 0
|
||||
nrdata(1) = m-2
|
||||
c main loop for the different sets of knots. m is a save upper bound
|
||||
c for the number of trials.
|
||||
60 do 200 iter = 1,m
|
||||
if(n.eq.nmin) ier = -2
|
||||
c find nrint, tne number of knot intervals.
|
||||
nrint = n-nmin+1
|
||||
c find the position of the additional knots which are needed for
|
||||
c the b-spline representation of s(u).
|
||||
nk1 = n-k1
|
||||
i = n
|
||||
do 70 j=1,k1
|
||||
t(j) = ub
|
||||
t(i) = ue
|
||||
i = i-1
|
||||
70 continue
|
||||
c compute the b-spline coefficients of the least-squares spline curve
|
||||
c sinf(u). the observation matrix a is built up row by row and
|
||||
c reduced to upper triangular form by givens transformations.
|
||||
c at the same time fp=f(p=inf) is computed.
|
||||
fp = 0.
|
||||
c initialize the b-spline coefficients and the observation matrix a.
|
||||
do 75 i=1,nc
|
||||
z(i) = 0.
|
||||
75 continue
|
||||
do 80 i=1,nk1
|
||||
do 80 j=1,k1
|
||||
a(i,j) = 0.
|
||||
80 continue
|
||||
l = k1
|
||||
jj = 0
|
||||
do 130 it=1,m
|
||||
c fetch the current data point u(it),x(it).
|
||||
ui = u(it)
|
||||
wi = w(it)
|
||||
do 83 j=1,idim
|
||||
jj = jj+1
|
||||
xi(j) = x(jj)*wi
|
||||
83 continue
|
||||
c search for knot interval t(l) <= ui < t(l+1).
|
||||
85 if(ui.lt.t(l+1) .or. l.eq.nk1) go to 90
|
||||
l = l+1
|
||||
go to 85
|
||||
c evaluate the (k+1) non-zero b-splines at ui and store them in q.
|
||||
90 call fpbspl(t,n,k,ui,l,h)
|
||||
do 95 i=1,k1
|
||||
q(it,i) = h(i)
|
||||
h(i) = h(i)*wi
|
||||
95 continue
|
||||
c rotate the new row of the observation matrix into triangle.
|
||||
j = l-k1
|
||||
do 110 i=1,k1
|
||||
j = j+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 110
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a(j,1),cos,sin)
|
||||
c transformations to right hand side.
|
||||
j1 = j
|
||||
do 97 j2 =1,idim
|
||||
call fprota(cos,sin,xi(j2),z(j1))
|
||||
j1 = j1+n
|
||||
97 continue
|
||||
if(i.eq.k1) go to 120
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 100 i1 = i3,k1
|
||||
i2 = i2+1
|
||||
c transformations to left hand side.
|
||||
call fprota(cos,sin,h(i1),a(j,i2))
|
||||
100 continue
|
||||
110 continue
|
||||
c add contribution of this row to the sum of squares of residual
|
||||
c right hand sides.
|
||||
120 do 125 j2=1,idim
|
||||
fp = fp+xi(j2)**2
|
||||
125 continue
|
||||
130 continue
|
||||
if(ier.eq.(-2)) fp0 = fp
|
||||
fpint(n) = fp0
|
||||
fpint(n-1) = fpold
|
||||
nrdata(n) = nplus
|
||||
c backward substitution to obtain the b-spline coefficients.
|
||||
j1 = 1
|
||||
do 135 j2=1,idim
|
||||
call fpback(a,z(j1),nk1,k1,c(j1),nest)
|
||||
j1 = j1+n
|
||||
135 continue
|
||||
c test whether the approximation sinf(u) is an acceptable solution.
|
||||
if(iopt.lt.0) go to 440
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 440
|
||||
c if f(p=inf) < s accept the choice of knots.
|
||||
if(fpms.lt.0.) go to 250
|
||||
c if n = nmax, sinf(u) is an interpolating spline curve.
|
||||
if(n.eq.nmax) go to 430
|
||||
c increase the number of knots.
|
||||
c if n=nest we cannot increase the number of knots because of
|
||||
c the storage capacity limitation.
|
||||
if(n.eq.nest) go to 420
|
||||
c determine the number of knots nplus we are going to add.
|
||||
if(ier.eq.0) go to 140
|
||||
nplus = 1
|
||||
ier = 0
|
||||
go to 150
|
||||
140 npl1 = nplus*2
|
||||
rn = nplus
|
||||
if(fpold-fp.gt.acc) npl1 = rn*fpms/(fpold-fp)
|
||||
nplus = min0(nplus*2,max0(npl1,nplus/2,1))
|
||||
150 fpold = fp
|
||||
c compute the sum of squared residuals for each knot interval
|
||||
c t(j+k) <= u(i) <= t(j+k+1) and store it in fpint(j),j=1,2,...nrint.
|
||||
fpart = 0.
|
||||
i = 1
|
||||
l = k2
|
||||
new = 0
|
||||
jj = 0
|
||||
do 180 it=1,m
|
||||
if(u(it).lt.t(l) .or. l.gt.nk1) go to 160
|
||||
new = 1
|
||||
l = l+1
|
||||
160 term = 0.
|
||||
l0 = l-k2
|
||||
do 175 j2=1,idim
|
||||
fac = 0.
|
||||
j1 = l0
|
||||
do 170 j=1,k1
|
||||
j1 = j1+1
|
||||
fac = fac+c(j1)*q(it,j)
|
||||
170 continue
|
||||
jj = jj+1
|
||||
term = term+(w(it)*(fac-x(jj)))**2
|
||||
l0 = l0+n
|
||||
175 continue
|
||||
fpart = fpart+term
|
||||
if(new.eq.0) go to 180
|
||||
store = term*half
|
||||
fpint(i) = fpart-store
|
||||
i = i+1
|
||||
fpart = store
|
||||
new = 0
|
||||
180 continue
|
||||
fpint(nrint) = fpart
|
||||
do 190 l=1,nplus
|
||||
c add a new knot.
|
||||
call fpknot(u,m,t,n,fpint,nrdata,nrint,nest,1)
|
||||
c if n=nmax we locate the knots as for interpolation
|
||||
if(n.eq.nmax) go to 10
|
||||
c test whether we cannot further increase the number of knots.
|
||||
if(n.eq.nest) go to 200
|
||||
190 continue
|
||||
c restart the computations with the new set of knots.
|
||||
200 continue
|
||||
c test whether the least-squares kth degree polynomial curve is a
|
||||
c solution of our approximation problem.
|
||||
250 if(ier.eq.(-2)) go to 440
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 2: determination of the smoothing spline curve sp(u). c
|
||||
c ********************************************************** c
|
||||
c we have determined the number of knots and their position. c
|
||||
c we now compute the b-spline coefficients of the smoothing curve c
|
||||
c sp(u). the observation matrix a is extended by the rows of matrix c
|
||||
c b expressing that the kth derivative discontinuities of sp(u) at c
|
||||
c the interior knots t(k+2),...t(n-k-1) must be zero. the corres- c
|
||||
c ponding weights of these additional rows are set to 1/p. c
|
||||
c iteratively we then have to determine the value of p such that f(p),c
|
||||
c the sum of squared residuals be = s. we already know that the least c
|
||||
c squares kth degree polynomial curve corresponds to p=0, and that c
|
||||
c the least-squares spline curve corresponds to p=infinity. the c
|
||||
c iteration process which is proposed here, makes use of rational c
|
||||
c interpolation. since f(p) is a convex and strictly decreasing c
|
||||
c function of p, it can be approximated by a rational function c
|
||||
c r(p) = (u*p+v)/(p+w). three values of p(p1,p2,p3) with correspond- c
|
||||
c ing values of f(p) (f1=f(p1)-s,f2=f(p2)-s,f3=f(p3)-s) are used c
|
||||
c to calculate the new value of p such that r(p)=s. convergence is c
|
||||
c guaranteed by taking f1>0 and f3<0. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c evaluate the discontinuity jump of the kth derivative of the
|
||||
c b-splines at the knots t(l),l=k+2,...n-k-1 and store in b.
|
||||
call fpdisc(t,n,k2,b,nest)
|
||||
c initial value for p.
|
||||
p1 = 0.
|
||||
f1 = fp0-s
|
||||
p3 = -one
|
||||
f3 = fpms
|
||||
p = 0.
|
||||
do 252 i=1,nk1
|
||||
p = p+a(i,1)
|
||||
252 continue
|
||||
rn = nk1
|
||||
p = rn/p
|
||||
ich1 = 0
|
||||
ich3 = 0
|
||||
n8 = n-nmin
|
||||
c iteration process to find the root of f(p) = s.
|
||||
do 360 iter=1,maxit
|
||||
c the rows of matrix b with weight 1/p are rotated into the
|
||||
c triangularised observation matrix a which is stored in g.
|
||||
pinv = one/p
|
||||
do 255 i=1,nc
|
||||
c(i) = z(i)
|
||||
255 continue
|
||||
do 260 i=1,nk1
|
||||
g(i,k2) = 0.
|
||||
do 260 j=1,k1
|
||||
g(i,j) = a(i,j)
|
||||
260 continue
|
||||
do 300 it=1,n8
|
||||
c the row of matrix b is rotated into triangle by givens transformation
|
||||
do 270 i=1,k2
|
||||
h(i) = b(it,i)*pinv
|
||||
270 continue
|
||||
do 275 j=1,idim
|
||||
xi(j) = 0.
|
||||
275 continue
|
||||
do 290 j=it,nk1
|
||||
piv = h(1)
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,g(j,1),cos,sin)
|
||||
c transformations to right hand side.
|
||||
j1 = j
|
||||
do 277 j2=1,idim
|
||||
call fprota(cos,sin,xi(j2),c(j1))
|
||||
j1 = j1+n
|
||||
277 continue
|
||||
if(j.eq.nk1) go to 300
|
||||
i2 = k1
|
||||
if(j.gt.n8) i2 = nk1-j
|
||||
do 280 i=1,i2
|
||||
c transformations to left hand side.
|
||||
i1 = i+1
|
||||
call fprota(cos,sin,h(i1),g(j,i1))
|
||||
h(i) = h(i1)
|
||||
280 continue
|
||||
h(i2+1) = 0.
|
||||
290 continue
|
||||
300 continue
|
||||
c backward substitution to obtain the b-spline coefficients.
|
||||
j1 = 1
|
||||
do 305 j2=1,idim
|
||||
call fpback(g,c(j1),nk1,k2,c(j1),nest)
|
||||
j1 =j1+n
|
||||
305 continue
|
||||
c computation of f(p).
|
||||
fp = 0.
|
||||
l = k2
|
||||
jj = 0
|
||||
do 330 it=1,m
|
||||
if(u(it).lt.t(l) .or. l.gt.nk1) go to 310
|
||||
l = l+1
|
||||
310 l0 = l-k2
|
||||
term = 0.
|
||||
do 325 j2=1,idim
|
||||
fac = 0.
|
||||
j1 = l0
|
||||
do 320 j=1,k1
|
||||
j1 = j1+1
|
||||
fac = fac+c(j1)*q(it,j)
|
||||
320 continue
|
||||
jj = jj+1
|
||||
term = term+(fac-x(jj))**2
|
||||
l0 = l0+n
|
||||
325 continue
|
||||
fp = fp+term*w(it)**2
|
||||
330 continue
|
||||
c test whether the approximation sp(u) is an acceptable solution.
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 440
|
||||
c test whether the maximal number of iterations is reached.
|
||||
if(iter.eq.maxit) go to 400
|
||||
c carry out one more step of the iteration process.
|
||||
p2 = p
|
||||
f2 = fpms
|
||||
if(ich3.ne.0) go to 340
|
||||
if((f2-f3).gt.acc) go to 335
|
||||
c our initial choice of p is too large.
|
||||
p3 = p2
|
||||
f3 = f2
|
||||
p = p*con4
|
||||
if(p.le.p1) p=p1*con9 + p2*con1
|
||||
go to 360
|
||||
335 if(f2.lt.0.) ich3=1
|
||||
340 if(ich1.ne.0) go to 350
|
||||
if((f1-f2).gt.acc) go to 345
|
||||
c our initial choice of p is too small
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
p = p/con4
|
||||
if(p3.lt.0.) go to 360
|
||||
if(p.ge.p3) p = p2*con1 + p3*con9
|
||||
go to 360
|
||||
345 if(f2.gt.0.) ich1=1
|
||||
c test whether the iteration process proceeds as theoretically
|
||||
c expected.
|
||||
350 if(f2.ge.f1 .or. f2.le.f3) go to 410
|
||||
c find the new value for p.
|
||||
p = fprati(p1,f1,p2,f2,p3,f3)
|
||||
360 continue
|
||||
c error codes and messages.
|
||||
400 ier = 3
|
||||
go to 440
|
||||
410 ier = 2
|
||||
go to 440
|
||||
420 ier = 1
|
||||
go to 440
|
||||
430 ier = -1
|
||||
440 return
|
||||
end
|
||||
393
cxx/fitpack/fppasu.f
Normal file
393
cxx/fitpack/fppasu.f
Normal file
@ -0,0 +1,393 @@
|
||||
subroutine fppasu(iopt,ipar,idim,u,mu,v,mv,z,mz,s,nuest,nvest,
|
||||
* tol,maxit,nc,nu,tu,nv,tv,c,fp,fp0,fpold,reducu,reducv,fpintu,
|
||||
* fpintv,lastdi,nplusu,nplusv,nru,nrv,nrdatu,nrdatv,wrk,lwrk,ier)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 s,tol,fp,fp0,fpold,reducu,reducv
|
||||
integer iopt,idim,mu,mv,mz,nuest,nvest,maxit,nc,nu,nv,lastdi,
|
||||
* nplusu,nplusv,lwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 u(mu),v(mv),z(mz*idim),tu(nuest),tv(nvest),c(nc*idim),
|
||||
* fpintu(nuest),fpintv(nvest),wrk(lwrk)
|
||||
integer ipar(2),nrdatu(nuest),nrdatv(nvest),nru(mu),nrv(mv)
|
||||
c ..local scalars
|
||||
real*8 acc,fpms,f1,f2,f3,p,p1,p2,p3,rn,one,con1,con9,con4,
|
||||
* peru,perv,ub,ue,vb,ve
|
||||
integer i,ich1,ich3,ifbu,ifbv,ifsu,ifsv,iter,j,lau1,lav1,laa,
|
||||
* l,lau,lav,lbu,lbv,lq,lri,lsu,lsv,l1,l2,l3,l4,mm,mpm,mvnu,ncof,
|
||||
* nk1u,nk1v,nmaxu,nmaxv,nminu,nminv,nplu,nplv,npl1,nrintu,
|
||||
* nrintv,nue,nuk,nve,nuu,nvv
|
||||
c ..function references..
|
||||
real*8 abs,fprati
|
||||
integer max0,min0
|
||||
c ..subroutine references..
|
||||
c fpgrpa,fpknot
|
||||
c ..
|
||||
c set constants
|
||||
one = 1
|
||||
con1 = 0.1e0
|
||||
con9 = 0.9e0
|
||||
con4 = 0.4e-01
|
||||
c set boundaries of the approximation domain
|
||||
ub = u(1)
|
||||
ue = u(mu)
|
||||
vb = v(1)
|
||||
ve = v(mv)
|
||||
c we partition the working space.
|
||||
lsu = 1
|
||||
lsv = lsu+mu*4
|
||||
lri = lsv+mv*4
|
||||
mm = max0(nuest,mv)
|
||||
lq = lri+mm*idim
|
||||
mvnu = nuest*mv*idim
|
||||
lau = lq+mvnu
|
||||
nuk = nuest*5
|
||||
lbu = lau+nuk
|
||||
lav = lbu+nuk
|
||||
nuk = nvest*5
|
||||
lbv = lav+nuk
|
||||
laa = lbv+nuk
|
||||
lau1 = lau
|
||||
if(ipar(1).eq.0) go to 10
|
||||
peru = ue-ub
|
||||
lau1 = laa
|
||||
laa = laa+4*nuest
|
||||
10 lav1 = lav
|
||||
if(ipar(2).eq.0) go to 20
|
||||
perv = ve-vb
|
||||
lav1 = laa
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 1: determination of the number of knots and their position. c
|
||||
c **************************************************************** c
|
||||
c given a set of knots we compute the least-squares spline sinf(u,v), c
|
||||
c and the corresponding sum of squared residuals fp=f(p=inf). c
|
||||
c if iopt=-1 sinf(u,v) is the requested approximation. c
|
||||
c if iopt=0 or iopt=1 we check whether we can accept the knots: c
|
||||
c if fp <=s we will continue with the current set of knots. c
|
||||
c if fp > s we will increase the number of knots and compute the c
|
||||
c corresponding least-squares spline until finally fp<=s. c
|
||||
c the initial choice of knots depends on the value of s and iopt. c
|
||||
c if s=0 we have spline interpolation; in that case the number of c
|
||||
c knots equals nmaxu = mu+4+2*ipar(1) and nmaxv = mv+4+2*ipar(2) c
|
||||
c if s>0 and c
|
||||
c *iopt=0 we first compute the least-squares polynomial c
|
||||
c nu=nminu=8 and nv=nminv=8 c
|
||||
c *iopt=1 we start with the knots found at the last call of the c
|
||||
c routine, except for the case that s > fp0; then we can compute c
|
||||
c the least-squares polynomial directly. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c determine the number of knots for polynomial approximation.
|
||||
20 nminu = 8
|
||||
nminv = 8
|
||||
if(iopt.lt.0) go to 100
|
||||
c acc denotes the absolute tolerance for the root of f(p)=s.
|
||||
acc = tol*s
|
||||
c find nmaxu and nmaxv which denote the number of knots in u- and v-
|
||||
c direction in case of spline interpolation.
|
||||
nmaxu = mu+4+2*ipar(1)
|
||||
nmaxv = mv+4+2*ipar(2)
|
||||
c find nue and nve which denote the maximum number of knots
|
||||
c allowed in each direction
|
||||
nue = min0(nmaxu,nuest)
|
||||
nve = min0(nmaxv,nvest)
|
||||
if(s.gt.0.) go to 60
|
||||
c if s = 0, s(u,v) is an interpolating spline.
|
||||
nu = nmaxu
|
||||
nv = nmaxv
|
||||
c test whether the required storage space exceeds the available one.
|
||||
if(nv.gt.nvest .or. nu.gt.nuest) go to 420
|
||||
c find the position of the interior knots in case of interpolation.
|
||||
c the knots in the u-direction.
|
||||
nuu = nu-8
|
||||
if(nuu.eq.0) go to 40
|
||||
i = 5
|
||||
j = 3-ipar(1)
|
||||
do 30 l=1,nuu
|
||||
tu(i) = u(j)
|
||||
i = i+1
|
||||
j = j+1
|
||||
30 continue
|
||||
c the knots in the v-direction.
|
||||
40 nvv = nv-8
|
||||
if(nvv.eq.0) go to 60
|
||||
i = 5
|
||||
j = 3-ipar(2)
|
||||
do 50 l=1,nvv
|
||||
tv(i) = v(j)
|
||||
i = i+1
|
||||
j = j+1
|
||||
50 continue
|
||||
go to 100
|
||||
c if s > 0 our initial choice of knots depends on the value of iopt.
|
||||
60 if(iopt.eq.0) go to 90
|
||||
if(fp0.le.s) go to 90
|
||||
c if iopt=1 and fp0 > s we start computing the least- squares spline
|
||||
c according to the set of knots found at the last call of the routine.
|
||||
c we determine the number of grid coordinates u(i) inside each knot
|
||||
c interval (tu(l),tu(l+1)).
|
||||
l = 5
|
||||
j = 1
|
||||
nrdatu(1) = 0
|
||||
mpm = mu-1
|
||||
do 70 i=2,mpm
|
||||
nrdatu(j) = nrdatu(j)+1
|
||||
if(u(i).lt.tu(l)) go to 70
|
||||
nrdatu(j) = nrdatu(j)-1
|
||||
l = l+1
|
||||
j = j+1
|
||||
nrdatu(j) = 0
|
||||
70 continue
|
||||
c we determine the number of grid coordinates v(i) inside each knot
|
||||
c interval (tv(l),tv(l+1)).
|
||||
l = 5
|
||||
j = 1
|
||||
nrdatv(1) = 0
|
||||
mpm = mv-1
|
||||
do 80 i=2,mpm
|
||||
nrdatv(j) = nrdatv(j)+1
|
||||
if(v(i).lt.tv(l)) go to 80
|
||||
nrdatv(j) = nrdatv(j)-1
|
||||
l = l+1
|
||||
j = j+1
|
||||
nrdatv(j) = 0
|
||||
80 continue
|
||||
go to 100
|
||||
c if iopt=0 or iopt=1 and s>=fp0, we start computing the least-squares
|
||||
c polynomial (which is a spline without interior knots).
|
||||
90 nu = nminu
|
||||
nv = nminv
|
||||
nrdatu(1) = mu-2
|
||||
nrdatv(1) = mv-2
|
||||
lastdi = 0
|
||||
nplusu = 0
|
||||
nplusv = 0
|
||||
fp0 = 0.
|
||||
fpold = 0.
|
||||
reducu = 0.
|
||||
reducv = 0.
|
||||
100 mpm = mu+mv
|
||||
ifsu = 0
|
||||
ifsv = 0
|
||||
ifbu = 0
|
||||
ifbv = 0
|
||||
p = -one
|
||||
c main loop for the different sets of knots.mpm=mu+mv is a save upper
|
||||
c bound for the number of trials.
|
||||
do 250 iter=1,mpm
|
||||
if(nu.eq.nminu .and. nv.eq.nminv) ier = -2
|
||||
c find nrintu (nrintv) which is the number of knot intervals in the
|
||||
c u-direction (v-direction).
|
||||
nrintu = nu-nminu+1
|
||||
nrintv = nv-nminv+1
|
||||
c find ncof, the number of b-spline coefficients for the current set
|
||||
c of knots.
|
||||
nk1u = nu-4
|
||||
nk1v = nv-4
|
||||
ncof = nk1u*nk1v
|
||||
c find the position of the additional knots which are needed for the
|
||||
c b-spline representation of s(u,v).
|
||||
if(ipar(1).ne.0) go to 110
|
||||
i = nu
|
||||
do 105 j=1,4
|
||||
tu(j) = ub
|
||||
tu(i) = ue
|
||||
i = i-1
|
||||
105 continue
|
||||
go to 120
|
||||
110 l1 = 4
|
||||
l2 = l1
|
||||
l3 = nu-3
|
||||
l4 = l3
|
||||
tu(l2) = ub
|
||||
tu(l3) = ue
|
||||
do 115 j=1,3
|
||||
l1 = l1+1
|
||||
l2 = l2-1
|
||||
l3 = l3+1
|
||||
l4 = l4-1
|
||||
tu(l2) = tu(l4)-peru
|
||||
tu(l3) = tu(l1)+peru
|
||||
115 continue
|
||||
120 if(ipar(2).ne.0) go to 130
|
||||
i = nv
|
||||
do 125 j=1,4
|
||||
tv(j) = vb
|
||||
tv(i) = ve
|
||||
i = i-1
|
||||
125 continue
|
||||
go to 140
|
||||
130 l1 = 4
|
||||
l2 = l1
|
||||
l3 = nv-3
|
||||
l4 = l3
|
||||
tv(l2) = vb
|
||||
tv(l3) = ve
|
||||
do 135 j=1,3
|
||||
l1 = l1+1
|
||||
l2 = l2-1
|
||||
l3 = l3+1
|
||||
l4 = l4-1
|
||||
tv(l2) = tv(l4)-perv
|
||||
tv(l3) = tv(l1)+perv
|
||||
135 continue
|
||||
c find the least-squares spline sinf(u,v) and calculate for each knot
|
||||
c interval tu(j+3)<=u<=tu(j+4) (tv(j+3)<=v<=tv(j+4)) the sum
|
||||
c of squared residuals fpintu(j),j=1,2,...,nu-7 (fpintv(j),j=1,2,...
|
||||
c ,nv-7) for the data points having their absciss (ordinate)-value
|
||||
c belonging to that interval.
|
||||
c fp gives the total sum of squared residuals.
|
||||
140 call fpgrpa(ifsu,ifsv,ifbu,ifbv,idim,ipar,u,mu,v,mv,z,mz,tu,
|
||||
* nu,tv,nv,p,c,nc,fp,fpintu,fpintv,mm,mvnu,wrk(lsu),wrk(lsv),
|
||||
* wrk(lri),wrk(lq),wrk(lau),wrk(lau1),wrk(lav),wrk(lav1),
|
||||
* wrk(lbu),wrk(lbv),nru,nrv)
|
||||
if(ier.eq.(-2)) fp0 = fp
|
||||
c test whether the least-squares spline is an acceptable solution.
|
||||
if(iopt.lt.0) go to 440
|
||||
fpms = fp-s
|
||||
if(abs(fpms) .lt. acc) go to 440
|
||||
c if f(p=inf) < s, we accept the choice of knots.
|
||||
if(fpms.lt.0.) go to 300
|
||||
c if nu=nmaxu and nv=nmaxv, sinf(u,v) is an interpolating spline.
|
||||
if(nu.eq.nmaxu .and. nv.eq.nmaxv) go to 430
|
||||
c increase the number of knots.
|
||||
c if nu=nue and nv=nve we cannot further increase the number of knots
|
||||
c because of the storage capacity limitation.
|
||||
if(nu.eq.nue .and. nv.eq.nve) go to 420
|
||||
ier = 0
|
||||
c adjust the parameter reducu or reducv according to the direction
|
||||
c in which the last added knots were located.
|
||||
if (lastdi.lt.0) go to 150
|
||||
if (lastdi.eq.0) go to 170
|
||||
go to 160
|
||||
150 reducu = fpold-fp
|
||||
go to 170
|
||||
160 reducv = fpold-fp
|
||||
c store the sum of squared residuals for the current set of knots.
|
||||
170 fpold = fp
|
||||
c find nplu, the number of knots we should add in the u-direction.
|
||||
nplu = 1
|
||||
if(nu.eq.nminu) go to 180
|
||||
npl1 = nplusu*2
|
||||
rn = nplusu
|
||||
if(reducu.gt.acc) npl1 = rn*fpms/reducu
|
||||
nplu = min0(nplusu*2,max0(npl1,nplusu/2,1))
|
||||
c find nplv, the number of knots we should add in the v-direction.
|
||||
180 nplv = 1
|
||||
if(nv.eq.nminv) go to 190
|
||||
npl1 = nplusv*2
|
||||
rn = nplusv
|
||||
if(reducv.gt.acc) npl1 = rn*fpms/reducv
|
||||
nplv = min0(nplusv*2,max0(npl1,nplusv/2,1))
|
||||
190 if (nplu.lt.nplv) go to 210
|
||||
if (nplu.eq.nplv) go to 200
|
||||
go to 230
|
||||
200 if(lastdi.lt.0) go to 230
|
||||
210 if(nu.eq.nue) go to 230
|
||||
c addition in the u-direction.
|
||||
lastdi = -1
|
||||
nplusu = nplu
|
||||
ifsu = 0
|
||||
do 220 l=1,nplusu
|
||||
c add a new knot in the u-direction
|
||||
call fpknot(u,mu,tu,nu,fpintu,nrdatu,nrintu,nuest,1)
|
||||
c test whether we cannot further increase the number of knots in the
|
||||
c u-direction.
|
||||
if(nu.eq.nue) go to 250
|
||||
220 continue
|
||||
go to 250
|
||||
230 if(nv.eq.nve) go to 210
|
||||
c addition in the v-direction.
|
||||
lastdi = 1
|
||||
nplusv = nplv
|
||||
ifsv = 0
|
||||
do 240 l=1,nplusv
|
||||
c add a new knot in the v-direction.
|
||||
call fpknot(v,mv,tv,nv,fpintv,nrdatv,nrintv,nvest,1)
|
||||
c test whether we cannot further increase the number of knots in the
|
||||
c v-direction.
|
||||
if(nv.eq.nve) go to 250
|
||||
240 continue
|
||||
c restart the computations with the new set of knots.
|
||||
250 continue
|
||||
c test whether the least-squares polynomial is a solution of our
|
||||
c approximation problem.
|
||||
300 if(ier.eq.(-2)) go to 440
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 2: determination of the smoothing spline sp(u,v) c
|
||||
c ***************************************************** c
|
||||
c we have determined the number of knots and their position. we now c
|
||||
c compute the b-spline coefficients of the smoothing spline sp(u,v). c
|
||||
c this smoothing spline varies with the parameter p in such a way thatc
|
||||
c f(p)=suml=1,idim(sumi=1,mu(sumj=1,mv((z(i,j,l)-sp(u(i),v(j),l))**2) c
|
||||
c is a continuous, strictly decreasing function of p. moreover the c
|
||||
c least-squares polynomial corresponds to p=0 and the least-squares c
|
||||
c spline to p=infinity. iteratively we then have to determine the c
|
||||
c positive value of p such that f(p)=s. the process which is proposed c
|
||||
c here makes use of rational interpolation. f(p) is approximated by a c
|
||||
c rational function r(p)=(u*p+v)/(p+w); three values of p (p1,p2,p3) c
|
||||
c with corresponding values of f(p) (f1=f(p1)-s,f2=f(p2)-s,f3=f(p3)-s)c
|
||||
c are used to calculate the new value of p such that r(p)=s. c
|
||||
c convergence is guaranteed by taking f1 > 0 and f3 < 0. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c initial value for p.
|
||||
p1 = 0.
|
||||
f1 = fp0-s
|
||||
p3 = -one
|
||||
f3 = fpms
|
||||
p = one
|
||||
ich1 = 0
|
||||
ich3 = 0
|
||||
c iteration process to find the root of f(p)=s.
|
||||
do 350 iter = 1,maxit
|
||||
c find the smoothing spline sp(u,v) and the corresponding sum of
|
||||
c squared residuals fp.
|
||||
call fpgrpa(ifsu,ifsv,ifbu,ifbv,idim,ipar,u,mu,v,mv,z,mz,tu,
|
||||
* nu,tv,nv,p,c,nc,fp,fpintu,fpintv,mm,mvnu,wrk(lsu),wrk(lsv),
|
||||
* wrk(lri),wrk(lq),wrk(lau),wrk(lau1),wrk(lav),wrk(lav1),
|
||||
* wrk(lbu),wrk(lbv),nru,nrv)
|
||||
c test whether the approximation sp(u,v) is an acceptable solution.
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 440
|
||||
c test whether the maximum allowable number of iterations has been
|
||||
c reached.
|
||||
if(iter.eq.maxit) go to 400
|
||||
c carry out one more step of the iteration process.
|
||||
p2 = p
|
||||
f2 = fpms
|
||||
if(ich3.ne.0) go to 320
|
||||
if((f2-f3).gt.acc) go to 310
|
||||
c our initial choice of p is too large.
|
||||
p3 = p2
|
||||
f3 = f2
|
||||
p = p*con4
|
||||
if(p.le.p1) p = p1*con9 + p2*con1
|
||||
go to 350
|
||||
310 if(f2.lt.0.) ich3 = 1
|
||||
320 if(ich1.ne.0) go to 340
|
||||
if((f1-f2).gt.acc) go to 330
|
||||
c our initial choice of p is too small
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
p = p/con4
|
||||
if(p3.lt.0.) go to 350
|
||||
if(p.ge.p3) p = p2*con1 + p3*con9
|
||||
go to 350
|
||||
c test whether the iteration process proceeds as theoretically
|
||||
c expected.
|
||||
330 if(f2.gt.0.) ich1 = 1
|
||||
340 if(f2.ge.f1 .or. f2.le.f3) go to 410
|
||||
c find the new value of p.
|
||||
p = fprati(p1,f1,p2,f2,p3,f3)
|
||||
350 continue
|
||||
c error codes and messages.
|
||||
400 ier = 3
|
||||
go to 440
|
||||
410 ier = 2
|
||||
go to 440
|
||||
420 ier = 1
|
||||
go to 440
|
||||
430 ier = -1
|
||||
fp = 0.
|
||||
440 return
|
||||
end
|
||||
617
cxx/fitpack/fpperi.f
Normal file
617
cxx/fitpack/fpperi.f
Normal file
@ -0,0 +1,617 @@
|
||||
recursive subroutine fpperi(iopt,x,y,w,m,k,s,nest,tol,maxit,
|
||||
* k1,k2,n,t,c,fp,fpint,z,a1,a2,b,g1,g2,q,nrdata,ier)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 s,tol,fp
|
||||
integer iopt,m,k,nest,maxit,k1,k2,n,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),y(m),w(m),t(nest),c(nest),fpint(nest),z(nest),
|
||||
* a1(nest,k1),a2(nest,k),b(nest,k2),g1(nest,k2),g2(nest,k1),
|
||||
* q(m,k1)
|
||||
integer nrdata(nest)
|
||||
c ..local scalars..
|
||||
real*8 acc,cos,c1,d1,fpart,fpms,fpold,fp0,f1,f2,f3,p,per,pinv,piv,
|
||||
*
|
||||
* p1,p2,p3,sin,store,term,wi,xi,yi,rn,one,con1,con4,con9,half
|
||||
integer i,ich1,ich3,ij,ik,it,iter,i1,i2,i3,j,jk,jper,j1,j2,kk,
|
||||
* kk1,k3,l,l0,l1,l5,mm,m1,new,nk1,nk2,nmax,nmin,nplus,npl1,
|
||||
* nrint,n10,n11,n7,n8
|
||||
c ..local arrays..
|
||||
real*8 h(6),h1(7),h2(6)
|
||||
c ..function references..
|
||||
real*8 abs,fprati
|
||||
integer max0,min0
|
||||
c ..subroutine references..
|
||||
c fpbacp,fpbspl,fpgivs,fpdisc,fpknot,fprota
|
||||
c ..
|
||||
c set constants
|
||||
one = 0.1e+01
|
||||
con1 = 0.1e0
|
||||
con9 = 0.9e0
|
||||
con4 = 0.4e-01
|
||||
half = 0.5e0
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 1: determination of the number of knots and their position c
|
||||
c ************************************************************** c
|
||||
c given a set of knots we compute the least-squares periodic spline c
|
||||
c sinf(x). if the sum f(p=inf) <= s we accept the choice of knots. c
|
||||
c the initial choice of knots depends on the value of s and iopt. c
|
||||
c if s=0 we have spline interpolation; in that case the number of c
|
||||
c knots equals nmax = m+2*k. c
|
||||
c if s > 0 and c
|
||||
c iopt=0 we first compute the least-squares polynomial of c
|
||||
c degree k; n = nmin = 2*k+2. since s(x) must be periodic we c
|
||||
c find that s(x) is a constant function. c
|
||||
c iopt=1 we start with the set of knots found at the last c
|
||||
c call of the routine, except for the case that s > fp0; then c
|
||||
c we compute directly the least-squares periodic polynomial. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
m1 = m-1
|
||||
kk = k
|
||||
kk1 = k1
|
||||
k3 = 3*k+1
|
||||
nmin = 2*k1
|
||||
c determine the length of the period of s(x).
|
||||
per = x(m)-x(1)
|
||||
if(iopt.lt.0) go to 50
|
||||
c calculation of acc, the absolute tolerance for the root of f(p)=s.
|
||||
acc = tol*s
|
||||
c determine nmax, the number of knots for periodic spline interpolation
|
||||
nmax = m+2*k
|
||||
if(s.gt.0. .or. nmax.eq.nmin) go to 30
|
||||
c if s=0, s(x) is an interpolating spline.
|
||||
n = nmax
|
||||
c test whether the required storage space exceeds the available one.
|
||||
if(n.gt.nest) go to 620
|
||||
c find the position of the interior knots in case of interpolation.
|
||||
5 if((k/2)*2 .eq. k) go to 20
|
||||
do 10 i=2,m1
|
||||
j = i+k
|
||||
t(j) = x(i)
|
||||
10 continue
|
||||
if(s.gt.0.) go to 50
|
||||
kk = k-1
|
||||
kk1 = k
|
||||
if(kk.gt.0) go to 50
|
||||
t(1) = t(m)-per
|
||||
t(2) = x(1)
|
||||
t(m+1) = x(m)
|
||||
t(m+2) = t(3)+per
|
||||
do 15 i=1,m1
|
||||
c(i) = y(i)
|
||||
15 continue
|
||||
c(m) = c(1)
|
||||
fp = 0.
|
||||
fpint(n) = fp0
|
||||
fpint(n-1) = 0.
|
||||
nrdata(n) = 0
|
||||
go to 630
|
||||
20 do 25 i=2,m1
|
||||
j = i+k
|
||||
t(j) = (x(i)+x(i-1))*half
|
||||
25 continue
|
||||
go to 50
|
||||
c if s > 0 our initial choice depends on the value of iopt.
|
||||
c if iopt=0 or iopt=1 and s>=fp0, we start computing the least-squares
|
||||
c periodic polynomial. (i.e. a constant function).
|
||||
c if iopt=1 and fp0>s we start computing the least-squares periodic
|
||||
c spline according the set of knots found at the last call of the
|
||||
c routine.
|
||||
30 if(iopt.eq.0) go to 35
|
||||
if(n.eq.nmin) go to 35
|
||||
fp0 = fpint(n)
|
||||
fpold = fpint(n-1)
|
||||
nplus = nrdata(n)
|
||||
if(fp0.gt.s) go to 50
|
||||
c the case that s(x) is a constant function is treated separetely.
|
||||
c find the least-squares constant c1 and compute fp0 at the same time.
|
||||
35 fp0 = 0.
|
||||
d1 = 0.
|
||||
c1 = 0.
|
||||
do 40 it=1,m1
|
||||
wi = w(it)
|
||||
yi = y(it)*wi
|
||||
call fpgivs(wi,d1,cos,sin)
|
||||
call fprota(cos,sin,yi,c1)
|
||||
fp0 = fp0+yi**2
|
||||
40 continue
|
||||
c1 = c1/d1
|
||||
c test whether that constant function is a solution of our problem.
|
||||
fpms = fp0-s
|
||||
if(fpms.lt.acc .or. nmax.eq.nmin) go to 640
|
||||
fpold = fp0
|
||||
c test whether the required storage space exceeds the available one.
|
||||
if(nmin.ge.nest) go to 620
|
||||
c start computing the least-squares periodic spline with one
|
||||
c interior knot.
|
||||
nplus = 1
|
||||
n = nmin+1
|
||||
mm = (m+1)/2
|
||||
t(k2) = x(mm)
|
||||
nrdata(1) = mm-2
|
||||
nrdata(2) = m1-mm
|
||||
c main loop for the different sets of knots. m is a save upper
|
||||
c bound for the number of trials.
|
||||
50 do 340 iter=1,m
|
||||
c find nrint, the number of knot intervals.
|
||||
nrint = n-nmin+1
|
||||
c find the position of the additional knots which are needed for
|
||||
c the b-spline representation of s(x). if we take
|
||||
c t(k+1) = x(1), t(n-k) = x(m)
|
||||
c t(k+1-j) = t(n-k-j) - per, j=1,2,...k
|
||||
c t(n-k+j) = t(k+1+j) + per, j=1,2,...k
|
||||
c then s(x) is a periodic spline with period per if the b-spline
|
||||
c coefficients satisfy the following conditions
|
||||
c c(n7+j) = c(j), j=1,...k (**) with n7=n-2*k-1.
|
||||
t(k1) = x(1)
|
||||
nk1 = n-k1
|
||||
nk2 = nk1+1
|
||||
t(nk2) = x(m)
|
||||
do 60 j=1,k
|
||||
i1 = nk2+j
|
||||
i2 = nk2-j
|
||||
j1 = k1+j
|
||||
j2 = k1-j
|
||||
t(i1) = t(j1)+per
|
||||
t(j2) = t(i2)-per
|
||||
60 continue
|
||||
c compute the b-spline coefficients c(j),j=1,...n7 of the least-squares
|
||||
c periodic spline sinf(x). the observation matrix a is built up row
|
||||
c by row while taking into account condition (**) and is reduced to
|
||||
c triangular form by givens transformations .
|
||||
c at the same time fp=f(p=inf) is computed.
|
||||
c the n7 x n7 triangularised upper matrix a has the form
|
||||
c ! a1 ' !
|
||||
c a = ! ' a2 !
|
||||
c ! 0 ' !
|
||||
c with a2 a n7 x k matrix and a1 a n10 x n10 upper triangular
|
||||
c matrix of bandwidth k+1 ( n10 = n7-k).
|
||||
c initialization.
|
||||
do 70 i=1,nk1
|
||||
z(i) = 0.
|
||||
do 70 j=1,kk1
|
||||
a1(i,j) = 0.
|
||||
70 continue
|
||||
n7 = nk1-k
|
||||
n10 = n7-kk
|
||||
jper = 0
|
||||
fp = 0.
|
||||
l = k1
|
||||
do 290 it=1,m1
|
||||
c fetch the current data point x(it),y(it)
|
||||
xi = x(it)
|
||||
wi = w(it)
|
||||
yi = y(it)*wi
|
||||
c search for knot interval t(l) <= xi < t(l+1).
|
||||
80 if(xi.lt.t(l+1)) go to 85
|
||||
l = l+1
|
||||
go to 80
|
||||
c evaluate the (k+1) non-zero b-splines at xi and store them in q.
|
||||
85 call fpbspl(t,n,k,xi,l,h)
|
||||
do 90 i=1,k1
|
||||
q(it,i) = h(i)
|
||||
h(i) = h(i)*wi
|
||||
90 continue
|
||||
l5 = l-k1
|
||||
c test whether the b-splines nj,k+1(x),j=1+n7,...nk1 are all zero at xi
|
||||
if(l5.lt.n10) go to 285
|
||||
if(jper.ne.0) go to 160
|
||||
c initialize the matrix a2.
|
||||
do 95 i=1,n7
|
||||
do 95 j=1,kk
|
||||
a2(i,j) = 0.
|
||||
95 continue
|
||||
jk = n10+1
|
||||
do 110 i=1,kk
|
||||
ik = jk
|
||||
do 100 j=1,kk1
|
||||
if(ik.le.0) go to 105
|
||||
a2(ik,i) = a1(ik,j)
|
||||
ik = ik-1
|
||||
100 continue
|
||||
105 jk = jk+1
|
||||
110 continue
|
||||
jper = 1
|
||||
c if one of the b-splines nj,k+1(x),j=n7+1,...nk1 is not zero at xi
|
||||
c we take account of condition (**) for setting up the new row
|
||||
c of the observation matrix a. this row is stored in the arrays h1
|
||||
c (the part with respect to a1) and h2 (the part with
|
||||
c respect to a2).
|
||||
160 do 170 i=1,kk
|
||||
h1(i) = 0.
|
||||
h2(i) = 0.
|
||||
170 continue
|
||||
h1(kk1) = 0.
|
||||
j = l5-n10
|
||||
do 210 i=1,kk1
|
||||
j = j+1
|
||||
l0 = j
|
||||
180 l1 = l0-kk
|
||||
if(l1.le.0) go to 200
|
||||
if(l1.le.n10) go to 190
|
||||
l0 = l1-n10
|
||||
go to 180
|
||||
190 h1(l1) = h(i)
|
||||
go to 210
|
||||
200 h2(l0) = h2(l0)+h(i)
|
||||
210 continue
|
||||
c rotate the new row of the observation matrix into triangle
|
||||
c by givens transformations.
|
||||
if(n10.le.0) go to 250
|
||||
c rotation with the rows 1,2,...n10 of matrix a.
|
||||
do 240 j=1,n10
|
||||
piv = h1(1)
|
||||
if(piv.ne.0.) go to 214
|
||||
do 212 i=1,kk
|
||||
h1(i) = h1(i+1)
|
||||
212 continue
|
||||
h1(kk1) = 0.
|
||||
go to 240
|
||||
c calculate the parameters of the givens transformation.
|
||||
214 call fpgivs(piv,a1(j,1),cos,sin)
|
||||
c transformation to the right hand side.
|
||||
call fprota(cos,sin,yi,z(j))
|
||||
c transformations to the left hand side with respect to a2.
|
||||
do 220 i=1,kk
|
||||
call fprota(cos,sin,h2(i),a2(j,i))
|
||||
220 continue
|
||||
if(j.eq.n10) go to 250
|
||||
i2 = min0(n10-j,kk)
|
||||
c transformations to the left hand side with respect to a1.
|
||||
do 230 i=1,i2
|
||||
i1 = i+1
|
||||
call fprota(cos,sin,h1(i1),a1(j,i1))
|
||||
h1(i) = h1(i1)
|
||||
230 continue
|
||||
h1(i1) = 0.
|
||||
240 continue
|
||||
c rotation with the rows n10+1,...n7 of matrix a.
|
||||
250 do 270 j=1,kk
|
||||
ij = n10+j
|
||||
if(ij.le.0) go to 270
|
||||
piv = h2(j)
|
||||
if(piv.eq.0.) go to 270
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a2(ij,j),cos,sin)
|
||||
c transformations to right hand side.
|
||||
call fprota(cos,sin,yi,z(ij))
|
||||
if(j.eq.kk) go to 280
|
||||
j1 = j+1
|
||||
c transformations to left hand side.
|
||||
do 260 i=j1,kk
|
||||
call fprota(cos,sin,h2(i),a2(ij,i))
|
||||
260 continue
|
||||
270 continue
|
||||
c add contribution of this row to the sum of squares of residual
|
||||
c right hand sides.
|
||||
280 fp = fp+yi**2
|
||||
go to 290
|
||||
c rotation of the new row of the observation matrix into
|
||||
c triangle in case the b-splines nj,k+1(x),j=n7+1,...n-k-1 are all zero
|
||||
c at xi.
|
||||
285 j = l5
|
||||
do 140 i=1,kk1
|
||||
j = j+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 140
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a1(j,1),cos,sin)
|
||||
c transformations to right hand side.
|
||||
call fprota(cos,sin,yi,z(j))
|
||||
if(i.eq.kk1) go to 150
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
c transformations to left hand side.
|
||||
do 130 i1=i3,kk1
|
||||
i2 = i2+1
|
||||
call fprota(cos,sin,h(i1),a1(j,i2))
|
||||
130 continue
|
||||
140 continue
|
||||
c add contribution of this row to the sum of squares of residual
|
||||
c right hand sides.
|
||||
150 fp = fp+yi**2
|
||||
290 continue
|
||||
fpint(n) = fp0
|
||||
fpint(n-1) = fpold
|
||||
nrdata(n) = nplus
|
||||
c backward substitution to obtain the b-spline coefficients c(j),j=1,.n
|
||||
call fpbacp(a1,a2,z,n7,kk,c,kk1,nest)
|
||||
c calculate from condition (**) the coefficients c(j+n7),j=1,2,...k.
|
||||
do 295 i=1,k
|
||||
j = i+n7
|
||||
c(j) = c(i)
|
||||
295 continue
|
||||
if(iopt.lt.0) go to 660
|
||||
c test whether the approximation sinf(x) is an acceptable solution.
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 660
|
||||
c if f(p=inf) < s accept the choice of knots.
|
||||
if(fpms.lt.0.) go to 350
|
||||
c if n=nmax, sinf(x) is an interpolating spline.
|
||||
if(n.eq.nmax) go to 630
|
||||
c increase the number of knots.
|
||||
c if n=nest we cannot increase the number of knots because of the
|
||||
c storage capacity limitation.
|
||||
if(n.eq.nest) go to 620
|
||||
c determine the number of knots nplus we are going to add.
|
||||
npl1 = nplus*2
|
||||
rn = nplus
|
||||
if(fpold-fp.gt.acc) npl1 = rn*fpms/(fpold-fp)
|
||||
nplus = min0(nplus*2,max0(npl1,nplus/2,1))
|
||||
fpold = fp
|
||||
c compute the sum(wi*(yi-s(xi))**2) for each knot interval
|
||||
c t(j+k) <= xi <= t(j+k+1) and store it in fpint(j),j=1,2,...nrint.
|
||||
fpart = 0.
|
||||
i = 1
|
||||
l = k1
|
||||
do 320 it=1,m1
|
||||
if(x(it).lt.t(l)) go to 300
|
||||
new = 1
|
||||
l = l+1
|
||||
300 term = 0.
|
||||
l0 = l-k2
|
||||
do 310 j=1,k1
|
||||
l0 = l0+1
|
||||
term = term+c(l0)*q(it,j)
|
||||
310 continue
|
||||
term = (w(it)*(term-y(it)))**2
|
||||
fpart = fpart+term
|
||||
if(new.eq.0) go to 320
|
||||
if(l.gt.k2) go to 315
|
||||
fpint(nrint) = term
|
||||
new = 0
|
||||
go to 320
|
||||
315 store = term*half
|
||||
fpint(i) = fpart-store
|
||||
i = i+1
|
||||
fpart = store
|
||||
new = 0
|
||||
320 continue
|
||||
fpint(nrint) = fpint(nrint)+fpart
|
||||
do 330 l=1,nplus
|
||||
c add a new knot
|
||||
call fpknot(x,m,t,n,fpint,nrdata,nrint,nest,1)
|
||||
c if n=nmax we locate the knots as for interpolation.
|
||||
if(n.eq.nmax) go to 5
|
||||
c test whether we cannot further increase the number of knots.
|
||||
if(n.eq.nest) go to 340
|
||||
330 continue
|
||||
c restart the computations with the new set of knots.
|
||||
340 continue
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 2: determination of the smoothing periodic spline sp(x). c
|
||||
c ************************************************************* c
|
||||
c we have determined the number of knots and their position. c
|
||||
c we now compute the b-spline coefficients of the smoothing spline c
|
||||
c sp(x). the observation matrix a is extended by the rows of matrix c
|
||||
c b expressing that the kth derivative discontinuities of sp(x) at c
|
||||
c the interior knots t(k+2),...t(n-k-1) must be zero. the corres- c
|
||||
c ponding weights of these additional rows are set to 1/sqrt(p). c
|
||||
c iteratively we then have to determine the value of p such that c
|
||||
c f(p)=sum(w(i)*(y(i)-sp(x(i)))**2) be = s. we already know that c
|
||||
c the least-squares constant function corresponds to p=0, and that c
|
||||
c the least-squares periodic spline corresponds to p=infinity. the c
|
||||
c iteration process which is proposed here, makes use of rational c
|
||||
c interpolation. since f(p) is a convex and strictly decreasing c
|
||||
c function of p, it can be approximated by a rational function c
|
||||
c r(p) = (u*p+v)/(p+w). three values of p(p1,p2,p3) with correspond- c
|
||||
c ing values of f(p) (f1=f(p1)-s,f2=f(p2)-s,f3=f(p3)-s) are used c
|
||||
c to calculate the new value of p such that r(p)=s. convergence is c
|
||||
c guaranteed by taking f1>0 and f3<0. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c evaluate the discontinuity jump of the kth derivative of the
|
||||
c b-splines at the knots t(l),l=k+2,...n-k-1 and store in b.
|
||||
350 call fpdisc(t,n,k2,b,nest)
|
||||
c initial value for p.
|
||||
p1 = 0.
|
||||
f1 = fp0-s
|
||||
p3 = -one
|
||||
f3 = fpms
|
||||
n11 = n10-1
|
||||
n8 = n7-1
|
||||
p = 0.
|
||||
l = n7
|
||||
do 352 i=1,k
|
||||
j = k+1-i
|
||||
p = p+a2(l,j)
|
||||
l = l-1
|
||||
if(l.eq.0) go to 356
|
||||
352 continue
|
||||
do 354 i=1,n10
|
||||
p = p+a1(i,1)
|
||||
354 continue
|
||||
356 rn = n7
|
||||
p = rn/p
|
||||
ich1 = 0
|
||||
ich3 = 0
|
||||
c iteration process to find the root of f(p) = s.
|
||||
do 595 iter=1,maxit
|
||||
c form the matrix g as the matrix a extended by the rows of matrix b.
|
||||
c the rows of matrix b with weight 1/p are rotated into
|
||||
c the triangularised observation matrix a.
|
||||
c after triangularisation our n7 x n7 matrix g takes the form
|
||||
c ! g1 ' !
|
||||
c g = ! ' g2 !
|
||||
c ! 0 ' !
|
||||
c with g2 a n7 x (k+1) matrix and g1 a n11 x n11 upper triangular
|
||||
c matrix of bandwidth k+2. ( n11 = n7-k-1)
|
||||
pinv = one/p
|
||||
c store matrix a into g
|
||||
do 360 i=1,n7
|
||||
c(i) = z(i)
|
||||
g1(i,k1) = a1(i,k1)
|
||||
g1(i,k2) = 0.
|
||||
g2(i,1) = 0.
|
||||
do 360 j=1,k
|
||||
g1(i,j) = a1(i,j)
|
||||
g2(i,j+1) = a2(i,j)
|
||||
360 continue
|
||||
l = n10
|
||||
do 370 j=1,k1
|
||||
if(l.le.0) go to 375
|
||||
g2(l,1) = a1(l,j)
|
||||
l = l-1
|
||||
370 continue
|
||||
375 do 540 it=1,n8
|
||||
c fetch a new row of matrix b and store it in the arrays h1 (the part
|
||||
c with respect to g1) and h2 (the part with respect to g2).
|
||||
yi = 0.
|
||||
do 380 i=1,k1
|
||||
h1(i) = 0.
|
||||
h2(i) = 0.
|
||||
380 continue
|
||||
h1(k2) = 0.
|
||||
if(it.gt.n11) go to 420
|
||||
l = it
|
||||
l0 = it
|
||||
do 390 j=1,k2
|
||||
if(l0.eq.n10) go to 400
|
||||
h1(j) = b(it,j)*pinv
|
||||
l0 = l0+1
|
||||
390 continue
|
||||
go to 470
|
||||
400 l0 = 1
|
||||
do 410 l1=j,k2
|
||||
h2(l0) = b(it,l1)*pinv
|
||||
l0 = l0+1
|
||||
410 continue
|
||||
go to 470
|
||||
420 l = 1
|
||||
i = it-n10
|
||||
do 460 j=1,k2
|
||||
i = i+1
|
||||
l0 = i
|
||||
430 l1 = l0-k1
|
||||
if(l1.le.0) go to 450
|
||||
if(l1.le.n11) go to 440
|
||||
l0 = l1-n11
|
||||
go to 430
|
||||
440 h1(l1) = b(it,j)*pinv
|
||||
go to 460
|
||||
450 h2(l0) = h2(l0)+b(it,j)*pinv
|
||||
460 continue
|
||||
if(n11.le.0) go to 510
|
||||
c rotate this row into triangle by givens transformations without
|
||||
c square roots.
|
||||
c rotation with the rows l,l+1,...n11.
|
||||
470 do 500 j=l,n11
|
||||
piv = h1(1)
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,g1(j,1),cos,sin)
|
||||
c transformation to right hand side.
|
||||
call fprota(cos,sin,yi,c(j))
|
||||
c transformation to the left hand side with respect to g2.
|
||||
do 480 i=1,k1
|
||||
call fprota(cos,sin,h2(i),g2(j,i))
|
||||
480 continue
|
||||
if(j.eq.n11) go to 510
|
||||
i2 = min0(n11-j,k1)
|
||||
c transformation to the left hand side with respect to g1.
|
||||
do 490 i=1,i2
|
||||
i1 = i+1
|
||||
call fprota(cos,sin,h1(i1),g1(j,i1))
|
||||
h1(i) = h1(i1)
|
||||
490 continue
|
||||
h1(i1) = 0.
|
||||
500 continue
|
||||
c rotation with the rows n11+1,...n7
|
||||
510 do 530 j=1,k1
|
||||
ij = n11+j
|
||||
if(ij.le.0) go to 530
|
||||
piv = h2(j)
|
||||
c calculate the parameters of the givens transformation
|
||||
call fpgivs(piv,g2(ij,j),cos,sin)
|
||||
c transformation to the right hand side.
|
||||
call fprota(cos,sin,yi,c(ij))
|
||||
if(j.eq.k1) go to 540
|
||||
j1 = j+1
|
||||
c transformation to the left hand side.
|
||||
do 520 i=j1,k1
|
||||
call fprota(cos,sin,h2(i),g2(ij,i))
|
||||
520 continue
|
||||
530 continue
|
||||
540 continue
|
||||
c backward substitution to obtain the b-spline coefficients
|
||||
c c(j),j=1,2,...n7 of sp(x).
|
||||
call fpbacp(g1,g2,c,n7,k1,c,k2,nest)
|
||||
c calculate from condition (**) the b-spline coefficients c(n7+j),j=1,.
|
||||
do 545 i=1,k
|
||||
j = i+n7
|
||||
c(j) = c(i)
|
||||
545 continue
|
||||
c computation of f(p).
|
||||
fp = 0.
|
||||
l = k1
|
||||
do 570 it=1,m1
|
||||
if(x(it).lt.t(l)) go to 550
|
||||
l = l+1
|
||||
550 l0 = l-k2
|
||||
term = 0.
|
||||
do 560 j=1,k1
|
||||
l0 = l0+1
|
||||
term = term+c(l0)*q(it,j)
|
||||
560 continue
|
||||
fp = fp+(w(it)*(term-y(it)))**2
|
||||
570 continue
|
||||
c test whether the approximation sp(x) is an acceptable solution.
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 660
|
||||
c test whether the maximal number of iterations is reached.
|
||||
if(iter.eq.maxit) go to 600
|
||||
c carry out one more step of the iteration process.
|
||||
p2 = p
|
||||
f2 = fpms
|
||||
if(ich3.ne.0) go to 580
|
||||
if((f2-f3) .gt. acc) go to 575
|
||||
c our initial choice of p is too large.
|
||||
p3 = p2
|
||||
f3 = f2
|
||||
p = p*con4
|
||||
if(p.le.p1) p = p1*con9 +p2*con1
|
||||
go to 595
|
||||
575 if(f2.lt.0.) ich3 = 1
|
||||
580 if(ich1.ne.0) go to 590
|
||||
if((f1-f2) .gt. acc) go to 585
|
||||
c our initial choice of p is too small
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
p = p/con4
|
||||
if(p3.lt.0.) go to 595
|
||||
if(p.ge.p3) p = p2*con1 +p3*con9
|
||||
go to 595
|
||||
585 if(f2.gt.0.) ich1 = 1
|
||||
c test whether the iteration process proceeds as theoretically
|
||||
c expected.
|
||||
590 if(f2.ge.f1 .or. f2.le.f3) go to 610
|
||||
c find the new value for p.
|
||||
p = fprati(p1,f1,p2,f2,p3,f3)
|
||||
595 continue
|
||||
c error codes and messages.
|
||||
600 ier = 3
|
||||
go to 660
|
||||
610 ier = 2
|
||||
go to 660
|
||||
620 ier = 1
|
||||
go to 660
|
||||
630 ier = -1
|
||||
go to 660
|
||||
640 ier = -2
|
||||
c the least-squares constant function c1 is a solution of our problem.
|
||||
c a constant function is a spline of degree k with all b-spline
|
||||
c coefficients equal to that constant c1.
|
||||
do 650 i=1,k1
|
||||
rn = k1-i
|
||||
t(i) = x(1)-rn*per
|
||||
c(i) = c1
|
||||
j = i+k1
|
||||
rn = i-1
|
||||
t(j) = x(m)+rn*per
|
||||
650 continue
|
||||
n = nmin
|
||||
fp = fp0
|
||||
fpint(n) = fp0
|
||||
fpint(n-1) = 0.
|
||||
nrdata(n) = 0
|
||||
660 return
|
||||
end
|
||||
73
cxx/fitpack/fppocu.f
Normal file
73
cxx/fitpack/fppocu.f
Normal file
@ -0,0 +1,73 @@
|
||||
recursive subroutine fppocu(idim,k,a,b,ib,db,nb,ie,de,ne,cp,np)
|
||||
implicit none
|
||||
c subroutine fppocu finds a idim-dimensional polynomial curve p(u) =
|
||||
c (p1(u),p2(u),...,pidim(u)) of degree k, satisfying certain derivative
|
||||
c constraints at the end points a and b, i.e.
|
||||
c (l)
|
||||
c if ib > 0 : pj (a) = db(idim*l+j), l=0,1,...,ib-1
|
||||
c (l)
|
||||
c if ie > 0 : pj (b) = de(idim*l+j), l=0,1,...,ie-1
|
||||
c
|
||||
c the polynomial curve is returned in its b-spline representation
|
||||
c ( coefficients cp(j), j=1,2,...,np )
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer idim,k,ib,nb,ie,ne,np
|
||||
real*8 a,b
|
||||
c ..array arguments..
|
||||
real*8 db(nb),de(ne),cp(np)
|
||||
c ..local scalars..
|
||||
real*8 ab,aki
|
||||
integer i,id,j,jj,l,ll,k1,k2
|
||||
c ..local array..
|
||||
real*8 work(6,6)
|
||||
c ..
|
||||
k1 = k+1
|
||||
k2 = 2*k1
|
||||
ab = b-a
|
||||
do 110 id=1,idim
|
||||
do 10 j=1,k1
|
||||
work(j,1) = 0.
|
||||
10 continue
|
||||
if(ib.eq.0) go to 50
|
||||
l = id
|
||||
do 20 i=1,ib
|
||||
work(1,i) = db(l)
|
||||
l = l+idim
|
||||
20 continue
|
||||
if(ib.eq.1) go to 50
|
||||
ll = ib
|
||||
do 40 j=2,ib
|
||||
ll = ll-1
|
||||
do 30 i=1,ll
|
||||
aki = k1-i
|
||||
work(j,i) = ab*work(j-1,i+1)/aki + work(j-1,i)
|
||||
30 continue
|
||||
40 continue
|
||||
50 if(ie.eq.0) go to 90
|
||||
l = id
|
||||
j = k1
|
||||
do 60 i=1,ie
|
||||
work(j,i) = de(l)
|
||||
l = l+idim
|
||||
j = j-1
|
||||
60 continue
|
||||
if(ie.eq.1) go to 90
|
||||
ll = ie
|
||||
do 80 jj=2,ie
|
||||
ll = ll-1
|
||||
j = k1+1-jj
|
||||
do 70 i=1,ll
|
||||
aki = k1-i
|
||||
work(j,i) = work(j+1,i) - ab*work(j,i+1)/aki
|
||||
j = j-1
|
||||
70 continue
|
||||
80 continue
|
||||
90 l = (id-1)*k2
|
||||
do 100 j=1,k1
|
||||
l = l+1
|
||||
cp(l) = work(j,1)
|
||||
100 continue
|
||||
110 continue
|
||||
return
|
||||
end
|
||||
411
cxx/fitpack/fppogr.f
Normal file
411
cxx/fitpack/fppogr.f
Normal file
@ -0,0 +1,411 @@
|
||||
recursive subroutine fppogr(iopt,ider,u,mu,v,mv,z,mz,z0,r,s,
|
||||
* nuest,nvest,tol,maxit,nc,nu,tu,nv,tv,c,fp,fp0,fpold,reducu,
|
||||
* reducv,fpintu,fpintv,dz,step,lastdi,nplusu,nplusv,lasttu,nru,
|
||||
* nrv,nrdatu,nrdatv,wrk,lwrk,ier)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer mu,mv,mz,nuest,nvest,maxit,nc,nu,nv,lastdi,nplusu,nplusv,
|
||||
* lasttu,lwrk,ier
|
||||
real*8 z0,r,s,tol,fp,fp0,fpold,reducu,reducv,step
|
||||
c ..array arguments..
|
||||
integer iopt(3),ider(2),nrdatu(nuest),nrdatv(nvest),nru(mu),
|
||||
* nrv(mv)
|
||||
real*8 u(mu),v(mv),z(mz),tu(nuest),tv(nvest),c(nc),fpintu(nuest),
|
||||
* fpintv(nvest),dz(3),wrk(lwrk)
|
||||
c ..local scalars..
|
||||
real*8 acc,fpms,f1,f2,f3,p,per,pi,p1,p2,p3,vb,ve,zmax,zmin,rn,one,
|
||||
*
|
||||
* con1,con4,con9
|
||||
integer i,ich1,ich3,ifbu,ifbv,ifsu,ifsv,istart,iter,i1,i2,j,ju,
|
||||
* ktu,l,l1,l2,l3,l4,mpm,mumin,mu0,mu1,nn,nplu,nplv,npl1,nrintu,
|
||||
* nrintv,nue,numax,nve,nvmax
|
||||
c ..local arrays..
|
||||
integer idd(2)
|
||||
real*8 dzz(3)
|
||||
c ..function references..
|
||||
real*8 abs,datan2,fprati
|
||||
integer max0,min0
|
||||
c ..subroutine references..
|
||||
c fpknot,fpopdi
|
||||
c ..
|
||||
c set constants
|
||||
one = 1d0
|
||||
con1 = 0.1e0
|
||||
con9 = 0.9e0
|
||||
con4 = 0.4e-01
|
||||
c initialization
|
||||
ifsu = 0
|
||||
ifsv = 0
|
||||
ifbu = 0
|
||||
ifbv = 0
|
||||
p = -one
|
||||
mumin = 4-iopt(3)
|
||||
if(ider(1).ge.0) mumin = mumin-1
|
||||
if(iopt(2).eq.1 .and. ider(2).eq.1) mumin = mumin-1
|
||||
pi = datan2(0d0,-one)
|
||||
per = pi+pi
|
||||
vb = v(1)
|
||||
ve = vb+per
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 1: determination of the number of knots and their position. c
|
||||
c **************************************************************** c
|
||||
c given a set of knots we compute the least-squares spline sinf(u,v) c
|
||||
c and the corresponding sum of squared residuals fp = f(p=inf). c
|
||||
c if iopt(1)=-1 sinf(u,v) is the requested approximation. c
|
||||
c if iopt(1)>=0 we check whether we can accept the knots: c
|
||||
c if fp <= s we will continue with the current set of knots. c
|
||||
c if fp > s we will increase the number of knots and compute the c
|
||||
c corresponding least-squares spline until finally fp <= s. c
|
||||
c the initial choice of knots depends on the value of s and iopt. c
|
||||
c if s=0 we have spline interpolation; in that case the number of c
|
||||
c knots in the u-direction equals nu=numax=mu+5+iopt(2)+iopt(3) c
|
||||
c and in the v-direction nv=nvmax=mv+7. c
|
||||
c if s>0 and c
|
||||
c iopt(1)=0 we first compute the least-squares polynomial,i.e. a c
|
||||
c spline without interior knots : nu=8 ; nv=8. c
|
||||
c iopt(1)=1 we start with the set of knots found at the last call c
|
||||
c of the routine, except for the case that s > fp0; then we c
|
||||
c compute the least-squares polynomial directly. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
if(iopt(1).lt.0) go to 120
|
||||
c acc denotes the absolute tolerance for the root of f(p)=s.
|
||||
acc = tol*s
|
||||
c numax and nvmax denote the number of knots needed for interpolation.
|
||||
numax = mu+5+iopt(2)+iopt(3)
|
||||
nvmax = mv+7
|
||||
nue = min0(numax,nuest)
|
||||
nve = min0(nvmax,nvest)
|
||||
if(s.gt.0.) go to 100
|
||||
c if s = 0, s(u,v) is an interpolating spline.
|
||||
nu = numax
|
||||
nv = nvmax
|
||||
c test whether the required storage space exceeds the available one.
|
||||
if(nu.gt.nuest .or. nv.gt.nvest) go to 420
|
||||
c find the position of the knots in the v-direction.
|
||||
do 10 l=1,mv
|
||||
tv(l+3) = v(l)
|
||||
10 continue
|
||||
tv(mv+4) = ve
|
||||
l1 = mv-2
|
||||
l2 = mv+5
|
||||
do 20 i=1,3
|
||||
tv(i) = v(l1)-per
|
||||
tv(l2) = v(i+1)+per
|
||||
l1 = l1+1
|
||||
l2 = l2+1
|
||||
20 continue
|
||||
c if not all the derivative values g(i,j) are given, we will first
|
||||
c estimate these values by computing a least-squares spline
|
||||
idd(1) = ider(1)
|
||||
if(idd(1).eq.0) idd(1) = 1
|
||||
if(idd(1).gt.0) dz(1) = z0
|
||||
idd(2) = ider(2)
|
||||
if(ider(1).lt.0) go to 30
|
||||
if(iopt(2).eq.0 .or. ider(2).ne.0) go to 70
|
||||
c we set up the knots in the u-direction for computing the least-squares
|
||||
c spline.
|
||||
30 i1 = 3
|
||||
i2 = mu-2
|
||||
nu = 4
|
||||
do 40 i=1,mu
|
||||
if(i1.gt.i2) go to 50
|
||||
nu = nu+1
|
||||
tu(nu) = u(i1)
|
||||
i1 = i1+2
|
||||
40 continue
|
||||
50 do 60 i=1,4
|
||||
tu(i) = 0.
|
||||
nu = nu+1
|
||||
tu(nu) = r
|
||||
60 continue
|
||||
c we compute the least-squares spline for estimating the derivatives.
|
||||
call fpopdi(ifsu,ifsv,ifbu,ifbv,u,mu,v,mv,z,mz,z0,dz,iopt,idd,
|
||||
* tu,nu,tv,nv,nuest,nvest,p,step,c,nc,fp,fpintu,fpintv,nru,nrv,
|
||||
* wrk,lwrk)
|
||||
ifsu = 0
|
||||
c if all the derivatives at the origin are known, we compute the
|
||||
c interpolating spline.
|
||||
c we set up the knots in the u-direction, needed for interpolation.
|
||||
70 nn = numax-8
|
||||
if(nn.eq.0) go to 95
|
||||
ju = 2-iopt(2)
|
||||
do 80 l=1,nn
|
||||
tu(l+4) = u(ju)
|
||||
ju = ju+1
|
||||
80 continue
|
||||
nu = numax
|
||||
l = nu
|
||||
do 90 i=1,4
|
||||
tu(i) = 0.
|
||||
tu(l) = r
|
||||
l = l-1
|
||||
90 continue
|
||||
c we compute the interpolating spline.
|
||||
95 call fpopdi(ifsu,ifsv,ifbu,ifbv,u,mu,v,mv,z,mz,z0,dz,iopt,idd,
|
||||
* tu,nu,tv,nv,nuest,nvest,p,step,c,nc,fp,fpintu,fpintv,nru,nrv,
|
||||
* wrk,lwrk)
|
||||
go to 430
|
||||
c if s>0 our initial choice of knots depends on the value of iopt(1).
|
||||
100 ier = 0
|
||||
if(iopt(1).eq.0) go to 115
|
||||
step = -step
|
||||
if(fp0.le.s) go to 115
|
||||
c if iopt(1)=1 and fp0 > s we start computing the least-squares spline
|
||||
c according to the set of knots found at the last call of the routine.
|
||||
c we determine the number of grid coordinates u(i) inside each knot
|
||||
c interval (tu(l),tu(l+1)).
|
||||
l = 5
|
||||
j = 1
|
||||
nrdatu(1) = 0
|
||||
mu0 = 2-iopt(2)
|
||||
mu1 = mu-2+iopt(3)
|
||||
do 105 i=mu0,mu1
|
||||
nrdatu(j) = nrdatu(j)+1
|
||||
if(u(i).lt.tu(l)) go to 105
|
||||
nrdatu(j) = nrdatu(j)-1
|
||||
l = l+1
|
||||
j = j+1
|
||||
nrdatu(j) = 0
|
||||
105 continue
|
||||
c we determine the number of grid coordinates v(i) inside each knot
|
||||
c interval (tv(l),tv(l+1)).
|
||||
l = 5
|
||||
j = 1
|
||||
nrdatv(1) = 0
|
||||
do 110 i=2,mv
|
||||
nrdatv(j) = nrdatv(j)+1
|
||||
if(v(i).lt.tv(l)) go to 110
|
||||
nrdatv(j) = nrdatv(j)-1
|
||||
l = l+1
|
||||
j = j+1
|
||||
nrdatv(j) = 0
|
||||
110 continue
|
||||
idd(1) = ider(1)
|
||||
idd(2) = ider(2)
|
||||
go to 120
|
||||
c if iopt(1)=0 or iopt(1)=1 and s >= fp0,we start computing the least-
|
||||
c squares polynomial (which is a spline without interior knots).
|
||||
115 ier = -2
|
||||
idd(1) = ider(1)
|
||||
idd(2) = 1
|
||||
nu = 8
|
||||
nv = 8
|
||||
nrdatu(1) = mu-3+iopt(2)+iopt(3)
|
||||
nrdatv(1) = mv-1
|
||||
lastdi = 0
|
||||
nplusu = 0
|
||||
nplusv = 0
|
||||
fp0 = 0.
|
||||
fpold = 0.
|
||||
reducu = 0.
|
||||
reducv = 0.
|
||||
c main loop for the different sets of knots.mpm=mu+mv is a save upper
|
||||
c bound for the number of trials.
|
||||
120 mpm = mu+mv
|
||||
do 270 iter=1,mpm
|
||||
c find nrintu (nrintv) which is the number of knot intervals in the
|
||||
c u-direction (v-direction).
|
||||
nrintu = nu-7
|
||||
nrintv = nv-7
|
||||
c find the position of the additional knots which are needed for the
|
||||
c b-spline representation of s(u,v).
|
||||
i = nu
|
||||
do 130 j=1,4
|
||||
tu(j) = 0.
|
||||
tu(i) = r
|
||||
i = i-1
|
||||
130 continue
|
||||
l1 = 4
|
||||
l2 = l1
|
||||
l3 = nv-3
|
||||
l4 = l3
|
||||
tv(l2) = vb
|
||||
tv(l3) = ve
|
||||
do 140 j=1,3
|
||||
l1 = l1+1
|
||||
l2 = l2-1
|
||||
l3 = l3+1
|
||||
l4 = l4-1
|
||||
tv(l2) = tv(l4)-per
|
||||
tv(l3) = tv(l1)+per
|
||||
140 continue
|
||||
c find an estimate of the range of possible values for the optimal
|
||||
c derivatives at the origin.
|
||||
ktu = nrdatu(1)+2-iopt(2)
|
||||
if(nrintu.eq.1) ktu = mu
|
||||
if(ktu.lt.mumin) ktu = mumin
|
||||
if(ktu.eq.lasttu) go to 150
|
||||
zmin = z0
|
||||
zmax = z0
|
||||
l = mv*ktu
|
||||
do 145 i=1,l
|
||||
if(z(i).lt.zmin) zmin = z(i)
|
||||
if(z(i).gt.zmax) zmax = z(i)
|
||||
145 continue
|
||||
step = zmax-zmin
|
||||
lasttu = ktu
|
||||
c find the least-squares spline sinf(u,v).
|
||||
150 call fpopdi(ifsu,ifsv,ifbu,ifbv,u,mu,v,mv,z,mz,z0,dz,iopt,idd,
|
||||
* tu,nu,tv,nv,nuest,nvest,p,step,c,nc,fp,fpintu,fpintv,nru,nrv,
|
||||
* wrk,lwrk)
|
||||
if(step.lt.0.) step = -step
|
||||
if(ier.eq.(-2)) fp0 = fp
|
||||
c test whether the least-squares spline is an acceptable solution.
|
||||
if(iopt(1).lt.0) go to 440
|
||||
fpms = fp-s
|
||||
if(abs(fpms) .lt. acc) go to 440
|
||||
c if f(p=inf) < s, we accept the choice of knots.
|
||||
if(fpms.lt.0.) go to 300
|
||||
c if nu=numax and nv=nvmax, sinf(u,v) is an interpolating spline
|
||||
if(nu.eq.numax .and. nv.eq.nvmax) go to 430
|
||||
c increase the number of knots.
|
||||
c if nu=nue and nv=nve we cannot further increase the number of knots
|
||||
c because of the storage capacity limitation.
|
||||
if(nu.eq.nue .and. nv.eq.nve) go to 420
|
||||
if(ider(1).eq.0) fpintu(1) = fpintu(1)+(z0-c(1))**2
|
||||
ier = 0
|
||||
c adjust the parameter reducu or reducv according to the direction
|
||||
c in which the last added knots were located.
|
||||
if (lastdi.lt.0) go to 160
|
||||
if (lastdi.eq.0) go to 155
|
||||
go to 170
|
||||
155 nplv = 3
|
||||
idd(2) = ider(2)
|
||||
fpold = fp
|
||||
go to 230
|
||||
160 reducu = fpold-fp
|
||||
go to 175
|
||||
170 reducv = fpold-fp
|
||||
c store the sum of squared residuals for the current set of knots.
|
||||
175 fpold = fp
|
||||
c find nplu, the number of knots we should add in the u-direction.
|
||||
nplu = 1
|
||||
if(nu.eq.8) go to 180
|
||||
npl1 = nplusu*2
|
||||
rn = nplusu
|
||||
if(reducu.gt.acc) npl1 = rn*fpms/reducu
|
||||
nplu = min0(nplusu*2,max0(npl1,nplusu/2,1))
|
||||
c find nplv, the number of knots we should add in the v-direction.
|
||||
180 nplv = 3
|
||||
if(nv.eq.8) go to 190
|
||||
npl1 = nplusv*2
|
||||
rn = nplusv
|
||||
if(reducv.gt.acc) npl1 = rn*fpms/reducv
|
||||
nplv = min0(nplusv*2,max0(npl1,nplusv/2,1))
|
||||
c test whether we are going to add knots in the u- or v-direction.
|
||||
190 if (nplu.lt.nplv) go to 210
|
||||
if (nplu.eq.nplv) go to 200
|
||||
go to 230
|
||||
200 if(lastdi.lt.0) go to 230
|
||||
210 if(nu.eq.nue) go to 230
|
||||
c addition in the u-direction.
|
||||
lastdi = -1
|
||||
nplusu = nplu
|
||||
ifsu = 0
|
||||
istart = 0
|
||||
if(iopt(2).eq.0) istart = 1
|
||||
do 220 l=1,nplusu
|
||||
c add a new knot in the u-direction
|
||||
call fpknot(u,mu,tu,nu,fpintu,nrdatu,nrintu,nuest,istart)
|
||||
c test whether we cannot further increase the number of knots in the
|
||||
c u-direction.
|
||||
if(nu.eq.nue) go to 270
|
||||
220 continue
|
||||
go to 270
|
||||
230 if(nv.eq.nve) go to 210
|
||||
c addition in the v-direction.
|
||||
lastdi = 1
|
||||
nplusv = nplv
|
||||
ifsv = 0
|
||||
do 240 l=1,nplusv
|
||||
c add a new knot in the v-direction.
|
||||
call fpknot(v,mv,tv,nv,fpintv,nrdatv,nrintv,nvest,1)
|
||||
c test whether we cannot further increase the number of knots in the
|
||||
c v-direction.
|
||||
if(nv.eq.nve) go to 270
|
||||
240 continue
|
||||
c restart the computations with the new set of knots.
|
||||
270 continue
|
||||
c test whether the least-squares polynomial is a solution of our
|
||||
c approximation problem.
|
||||
300 if(ier.eq.(-2)) go to 440
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 2: determination of the smoothing spline sp(u,v) c
|
||||
c ***************************************************** c
|
||||
c we have determined the number of knots and their position. we now c
|
||||
c compute the b-spline coefficients of the smoothing spline sp(u,v). c
|
||||
c this smoothing spline depends on the parameter p in such a way that c
|
||||
c f(p) = sumi=1,mu(sumj=1,mv((z(i,j)-sp(u(i),v(j)))**2) c
|
||||
c is a continuous, strictly decreasing function of p. moreover the c
|
||||
c least-squares polynomial corresponds to p=0 and the least-squares c
|
||||
c spline to p=infinity. then iteratively we have to determine the c
|
||||
c positive value of p such that f(p)=s. the process which is proposed c
|
||||
c here makes use of rational interpolation. f(p) is approximated by a c
|
||||
c rational function r(p)=(u*p+v)/(p+w); three values of p (p1,p2,p3) c
|
||||
c with corresponding values of f(p) (f1=f(p1)-s,f2=f(p2)-s,f3=f(p3)-s)c
|
||||
c are used to calculate the new value of p such that r(p)=s. c
|
||||
c convergence is guaranteed by taking f1 > 0 and f3 < 0. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c initial value for p.
|
||||
p1 = 0.
|
||||
f1 = fp0-s
|
||||
p3 = -one
|
||||
f3 = fpms
|
||||
p = one
|
||||
dzz(1) = dz(1)
|
||||
dzz(2) = dz(2)
|
||||
dzz(3) = dz(3)
|
||||
ich1 = 0
|
||||
ich3 = 0
|
||||
c iteration process to find the root of f(p)=s.
|
||||
do 350 iter = 1,maxit
|
||||
c find the smoothing spline sp(u,v) and the corresponding sum f(p).
|
||||
call fpopdi(ifsu,ifsv,ifbu,ifbv,u,mu,v,mv,z,mz,z0,dzz,iopt,idd,
|
||||
* tu,nu,tv,nv,nuest,nvest,p,step,c,nc,fp,fpintu,fpintv,nru,nrv,
|
||||
* wrk,lwrk)
|
||||
c test whether the approximation sp(u,v) is an acceptable solution.
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 440
|
||||
c test whether the maximum allowable number of iterations has been
|
||||
c reached.
|
||||
if(iter.eq.maxit) go to 400
|
||||
c carry out one more step of the iteration process.
|
||||
p2 = p
|
||||
f2 = fpms
|
||||
if(ich3.ne.0) go to 320
|
||||
if((f2-f3).gt.acc) go to 310
|
||||
c our initial choice of p is too large.
|
||||
p3 = p2
|
||||
f3 = f2
|
||||
p = p*con4
|
||||
if(p.le.p1) p = p1*con9 + p2*con1
|
||||
go to 350
|
||||
310 if(f2.lt.0.) ich3 = 1
|
||||
320 if(ich1.ne.0) go to 340
|
||||
if((f1-f2).gt.acc) go to 330
|
||||
c our initial choice of p is too small
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
p = p/con4
|
||||
if(p3.lt.0.) go to 350
|
||||
if(p.ge.p3) p = p2*con1 + p3*con9
|
||||
go to 350
|
||||
c test whether the iteration process proceeds as theoretically
|
||||
c expected.
|
||||
330 if(f2.gt.0.) ich1 = 1
|
||||
340 if(f2.ge.f1 .or. f2.le.f3) go to 410
|
||||
c find the new value of p.
|
||||
p = fprati(p1,f1,p2,f2,p3,f3)
|
||||
350 continue
|
||||
c error codes and messages.
|
||||
400 ier = 3
|
||||
go to 440
|
||||
410 ier = 2
|
||||
go to 440
|
||||
420 ier = 1
|
||||
go to 440
|
||||
430 ier = -1
|
||||
fp = 0.
|
||||
440 return
|
||||
end
|
||||
841
cxx/fitpack/fppola.f
Normal file
841
cxx/fitpack/fppola.f
Normal file
@ -0,0 +1,841 @@
|
||||
recursive subroutine fppola(iopt1,iopt2,iopt3,m,u,v,z,w,rad,s,
|
||||
* nuest,nvest,eta,tol,maxit,ib1,ib3,nc,ncc,intest,nrest,nu,tu,nv,
|
||||
* tv,c,fp,sup,fpint,coord,f,ff,row,cs,cosi,a,q,bu,bv,spu,spv,h,
|
||||
* index,nummer,wrk,lwrk,ier)
|
||||
implicit none
|
||||
c ..scalar arguments..
|
||||
integer iopt1,iopt2,iopt3,m,nuest,nvest,maxit,ib1,ib3,nc,ncc,
|
||||
* intest,nrest,nu,nv,lwrk,ier
|
||||
real*8 s,eta,tol,fp,sup
|
||||
c ..array arguments..
|
||||
integer index(nrest),nummer(m)
|
||||
real*8 u(m),v(m),z(m),w(m),tu(nuest),tv(nvest),c(nc),fpint(intest)
|
||||
*,
|
||||
* coord(intest),f(ncc),ff(nc),row(nvest),cs(nvest),cosi(5,nvest),
|
||||
* a(ncc,ib1),q(ncc,ib3),bu(nuest,5),bv(nvest,5),spu(m,4),spv(m,4),
|
||||
* h(ib3),wrk(lwrk)
|
||||
c ..user supplied function..
|
||||
real*8 rad
|
||||
c ..local scalars..
|
||||
real*8 acc,arg,co,c1,c2,c3,c4,dmax,eps,fac,fac1,fac2,fpmax,fpms,
|
||||
* f1,f2,f3,hui,huj,p,pi,pinv,piv,pi2,p1,p2,p3,r,ratio,si,sigma,
|
||||
* sq,store,uu,u2,u3,wi,zi,rn,one,two,three,con1,con4,con9,half,ten
|
||||
integer i,iband,iband3,iband4,ich1,ich3,ii,il,in,ipar,ipar1,irot,
|
||||
* iter,i1,i2,i3,j,jrot,j1,j2,k,l,la,lf,lh,ll,lu,lv,lwest,l1,l2,
|
||||
* l3,l4,ncof,ncoff,nvv,nv4,nreg,nrint,nrr,nr1,nuu,nu4,num,num1,
|
||||
* numin,nvmin,rank,iband1, jlu
|
||||
c ..local arrays..
|
||||
real*8 hu(4),hv(4)
|
||||
c ..function references..
|
||||
real*8 abs,atan,cos,fprati,sin,sqrt
|
||||
integer min0
|
||||
c ..subroutine references..
|
||||
c fporde,fpbspl,fpback,fpgivs,fprota,fprank,fpdisc,fprppo
|
||||
c ..
|
||||
c set constants
|
||||
one = 1
|
||||
two = 2
|
||||
three = 3
|
||||
ten = 10
|
||||
half = 0.5e0
|
||||
con1 = 0.1e0
|
||||
con9 = 0.9e0
|
||||
con4 = 0.4e-01
|
||||
pi = atan(one)*4
|
||||
pi2 = pi+pi
|
||||
ipar = iopt2*(iopt2+3)/2
|
||||
ipar1 = ipar+1
|
||||
eps = sqrt(eta)
|
||||
if(iopt1.lt.0) go to 90
|
||||
numin = 9
|
||||
nvmin = 9+iopt2*(iopt2+1)
|
||||
c calculation of acc, the absolute tolerance for the root of f(p)=s.
|
||||
acc = tol*s
|
||||
if(iopt1.eq.0) go to 10
|
||||
if(s.lt.sup) then
|
||||
if (nv.lt.nvmin) go to 70
|
||||
go to 90
|
||||
endif
|
||||
c if iopt1 = 0 we begin by computing the weighted least-squares
|
||||
c polymomial of the form
|
||||
c s(u,v) = f(1)*(1-u**3)+f(2)*u**3+f(3)*(u**2-u**3)+f(4)*(u-u**3)
|
||||
c where f(4) = 0 if iopt2> 0 , f(3) = 0 if iopt2 > 1 and
|
||||
c f(2) = 0 if iopt3> 0.
|
||||
c the corresponding weighted sum of squared residuals gives the upper
|
||||
c bound sup for the smoothing factor s.
|
||||
10 sup = 0.
|
||||
do 20 i=1,4
|
||||
f(i) = 0.
|
||||
do 20 j=1,4
|
||||
a(i,j) = 0.
|
||||
20 continue
|
||||
do 50 i=1,m
|
||||
wi = w(i)
|
||||
zi = z(i)*wi
|
||||
uu = u(i)
|
||||
u2 = uu*uu
|
||||
u3 = uu*u2
|
||||
h(1) = (one-u3)*wi
|
||||
h(2) = u3*wi
|
||||
h(3) = u2*(one-uu)*wi
|
||||
h(4) = uu*(one-u2)*wi
|
||||
if(iopt3.ne.0) h(2) = 0.
|
||||
if(iopt2.gt.1) h(3) = 0.
|
||||
if(iopt2.gt.0) h(4) = 0.
|
||||
do 40 j=1,4
|
||||
piv = h(j)
|
||||
if(piv.eq.0.) go to 40
|
||||
call fpgivs(piv,a(j,1),co,si)
|
||||
call fprota(co,si,zi,f(j))
|
||||
if(j.eq.4) go to 40
|
||||
j1 = j+1
|
||||
j2 = 1
|
||||
do 30 l=j1,4
|
||||
j2 = j2+1
|
||||
call fprota(co,si,h(l),a(j,j2))
|
||||
30 continue
|
||||
40 continue
|
||||
sup = sup+zi*zi
|
||||
50 continue
|
||||
if(a(4,1).ne.0.) f(4) = f(4)/a(4,1)
|
||||
if(a(3,1).ne.0.) f(3) = (f(3)-a(3,2)*f(4))/a(3,1)
|
||||
if(a(2,1).ne.0.) f(2) = (f(2)-a(2,2)*f(3)-a(2,3)*f(4))/a(2,1)
|
||||
if(a(1,1).ne.0.)
|
||||
* f(1) = (f(1)-a(1,2)*f(2)-a(1,3)*f(3)-a(1,4)*f(4))/a(1,1)
|
||||
c find the b-spline representation of this least-squares polynomial
|
||||
c1 = f(1)
|
||||
c4 = f(2)
|
||||
c2 = f(4)/three+c1
|
||||
c3 = (f(3)+two*f(4))/three+c1
|
||||
nu = 8
|
||||
nv = 8
|
||||
do 60 i=1,4
|
||||
c(i) = c1
|
||||
c(i+4) = c2
|
||||
c(i+8) = c3
|
||||
c(i+12) = c4
|
||||
tu(i) = 0.
|
||||
tu(i+4) = one
|
||||
rn = 2*i-9
|
||||
tv(i) = rn*pi
|
||||
rn = 2*i-1
|
||||
tv(i+4) = rn*pi
|
||||
60 continue
|
||||
fp = sup
|
||||
c test whether the least-squares polynomial is an acceptable solution
|
||||
fpms = sup-s
|
||||
if(fpms.lt.acc) go to 960
|
||||
c test whether we cannot further increase the number of knots.
|
||||
70 if(nuest.lt.numin .or. nvest.lt.nvmin) go to 950
|
||||
c find the initial set of interior knots of the spline in case iopt1=0.
|
||||
nu = numin
|
||||
nv = nvmin
|
||||
tu(5) = half
|
||||
nvv = nv-8
|
||||
rn = nvv+1
|
||||
fac = pi2/rn
|
||||
do 80 i=1,nvv
|
||||
rn = i
|
||||
tv(i+4) = rn*fac-pi
|
||||
80 continue
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 1 : computation of least-squares bicubic splines. c
|
||||
c ****************************************************** c
|
||||
c if iopt1<0 we compute the least-squares bicubic spline according c
|
||||
c to the given set of knots. c
|
||||
c if iopt1>=0 we compute least-squares bicubic splines with in- c
|
||||
c creasing numbers of knots until the corresponding sum f(p=inf)<=s. c
|
||||
c the initial set of knots then depends on the value of iopt1 c
|
||||
c if iopt1=0 we start with one interior knot in the u-direction c
|
||||
c (0.5) and 1+iopt2*(iopt2+1) in the v-direction. c
|
||||
c if iopt1>0 we start with the set of knots found at the last c
|
||||
c call of the routine. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c main loop for the different sets of knots. m is a save upper bound
|
||||
c for the number of trials.
|
||||
90 do 570 iter=1,m
|
||||
c find the position of the additional knots which are needed for the
|
||||
c b-spline representation of s(u,v).
|
||||
l1 = 4
|
||||
l2 = l1
|
||||
l3 = nv-3
|
||||
l4 = l3
|
||||
tv(l2) = -pi
|
||||
tv(l3) = pi
|
||||
do 120 i=1,3
|
||||
l1 = l1+1
|
||||
l2 = l2-1
|
||||
l3 = l3+1
|
||||
l4 = l4-1
|
||||
tv(l2) = tv(l4)-pi2
|
||||
tv(l3) = tv(l1)+pi2
|
||||
120 continue
|
||||
l = nu
|
||||
do 130 i=1,4
|
||||
tu(i) = 0.
|
||||
tu(l) = one
|
||||
l = l-1
|
||||
130 continue
|
||||
c find nrint, the total number of knot intervals and nreg, the number
|
||||
c of panels in which the approximation domain is subdivided by the
|
||||
c intersection of knots.
|
||||
nuu = nu-7
|
||||
nvv = nv-7
|
||||
nrr = nvv/2
|
||||
nr1 = nrr+1
|
||||
nrint = nuu+nvv
|
||||
nreg = nuu*nvv
|
||||
c arrange the data points according to the panel they belong to.
|
||||
call fporde(u,v,m,3,3,tu,nu,tv,nv,nummer,index,nreg)
|
||||
if(iopt2.eq.0) go to 195
|
||||
c find the b-spline coefficients cosi of the cubic spline
|
||||
c approximations for cr(v)=rad(v)*cos(v) and sr(v) = rad(v)*sin(v)
|
||||
c if iopt2=1, and additionally also for cr(v)**2,sr(v)**2 and
|
||||
c 2*cr(v)*sr(v) if iopt2=2
|
||||
do 140 i=1,nvv
|
||||
do 135 j=1,ipar
|
||||
cosi(j,i) = 0.
|
||||
135 continue
|
||||
do 140 j=1,nvv
|
||||
a(i,j) = 0.
|
||||
140 continue
|
||||
c the coefficients cosi are obtained from interpolation conditions
|
||||
c at the knots tv(i),i=4,5,...nv-4.
|
||||
do 175 i=1,nvv
|
||||
l2 = i+3
|
||||
arg = tv(l2)
|
||||
call fpbspl(tv,nv,3,arg,l2,hv)
|
||||
do 145 j=1,nvv
|
||||
row(j) = 0.
|
||||
145 continue
|
||||
ll = i
|
||||
do 150 j=1,3
|
||||
if(ll.gt.nvv) ll= 1
|
||||
row(ll) = row(ll)+hv(j)
|
||||
ll = ll+1
|
||||
150 continue
|
||||
co = cos(arg)
|
||||
si = sin(arg)
|
||||
r = rad(arg)
|
||||
cs(1) = co*r
|
||||
cs(2) = si*r
|
||||
if(iopt2.eq.1) go to 155
|
||||
cs(3) = cs(1)*cs(1)
|
||||
cs(4) = cs(2)*cs(2)
|
||||
cs(5) = cs(1)*cs(2)
|
||||
155 do 170 j=1,nvv
|
||||
piv = row(j)
|
||||
if(piv.eq.0.) go to 170
|
||||
call fpgivs(piv,a(j,1),co,si)
|
||||
do 160 l=1,ipar
|
||||
call fprota(co,si,cs(l),cosi(l,j))
|
||||
160 continue
|
||||
if(j.eq.nvv) go to 175
|
||||
j1 = j+1
|
||||
j2 = 1
|
||||
do 165 l=j1,nvv
|
||||
j2 = j2+1
|
||||
call fprota(co,si,row(l),a(j,j2))
|
||||
165 continue
|
||||
170 continue
|
||||
175 continue
|
||||
do 190 l=1,ipar
|
||||
do 180 j=1,nvv
|
||||
cs(j) = cosi(l,j)
|
||||
180 continue
|
||||
call fpback(a,cs,nvv,nvv,cs,ncc)
|
||||
do 185 j=1,nvv
|
||||
cosi(l,j) = cs(j)
|
||||
185 continue
|
||||
190 continue
|
||||
c find ncof, the dimension of the spline and ncoff, the number
|
||||
c of coefficients in the standard b-spline representation.
|
||||
195 nu4 = nu-4
|
||||
nv4 = nv-4
|
||||
ncoff = nu4*nv4
|
||||
ncof = ipar1+nvv*(nu4-1-iopt2-iopt3)
|
||||
c find the bandwidth of the observation matrix a.
|
||||
iband = 4*nvv
|
||||
if(nuu-iopt2-iopt3.le.1) iband = ncof
|
||||
iband1 = iband-1
|
||||
c initialize the observation matrix a.
|
||||
do 200 i=1,ncof
|
||||
f(i) = 0.
|
||||
do 200 j=1,iband
|
||||
a(i,j) = 0.
|
||||
200 continue
|
||||
c initialize the sum of squared residuals.
|
||||
fp = 0.
|
||||
ratio = one+tu(6)/tu(5)
|
||||
c fetch the data points in the new order. main loop for the
|
||||
c different panels.
|
||||
do 380 num=1,nreg
|
||||
c fix certain constants for the current panel; jrot records the column
|
||||
c number of the first non-zero element in a row of the observation
|
||||
c matrix according to a data point of the panel.
|
||||
num1 = num-1
|
||||
lu = num1/nvv
|
||||
l1 = lu+4
|
||||
lv = num1-lu*nvv+1
|
||||
l2 = lv+3
|
||||
jrot = 0
|
||||
if(lu.gt.iopt2) jrot = ipar1+(lu-iopt2-1)*nvv
|
||||
lu = lu+1
|
||||
c test whether there are still data points in the current panel.
|
||||
in = index(num)
|
||||
210 if(in.eq.0) go to 380
|
||||
c fetch a new data point.
|
||||
wi = w(in)
|
||||
zi = z(in)*wi
|
||||
c evaluate for the u-direction, the 4 non-zero b-splines at u(in)
|
||||
call fpbspl(tu,nu,3,u(in),l1,hu)
|
||||
c evaluate for the v-direction, the 4 non-zero b-splines at v(in)
|
||||
call fpbspl(tv,nv,3,v(in),l2,hv)
|
||||
c store the value of these b-splines in spu and spv resp.
|
||||
do 220 i=1,4
|
||||
spu(in,i) = hu(i)
|
||||
spv(in,i) = hv(i)
|
||||
220 continue
|
||||
c initialize the new row of observation matrix.
|
||||
do 240 i=1,iband
|
||||
h(i) = 0.
|
||||
240 continue
|
||||
c calculate the non-zero elements of the new row by making the cross
|
||||
c products of the non-zero b-splines in u- and v-direction and
|
||||
c by taking into account the conditions of the splines.
|
||||
do 250 i=1,nvv
|
||||
row(i) = 0.
|
||||
250 continue
|
||||
c take into account the periodicity condition of the bicubic splines.
|
||||
ll = lv
|
||||
do 260 i=1,4
|
||||
if(ll.gt.nvv) ll=1
|
||||
row(ll) = row(ll)+hv(i)
|
||||
ll = ll+1
|
||||
260 continue
|
||||
c take into account the other conditions of the splines.
|
||||
if(iopt2.eq.0 .or. lu.gt.iopt2+1) go to 280
|
||||
do 270 l=1,ipar
|
||||
cs(l) = 0.
|
||||
do 270 i=1,nvv
|
||||
cs(l) = cs(l)+row(i)*cosi(l,i)
|
||||
270 continue
|
||||
c fill in the non-zero elements of the new row.
|
||||
280 j1 = 0
|
||||
do 330 j =1,4
|
||||
jlu = j+lu
|
||||
huj = hu(j)
|
||||
if(jlu.gt.iopt2+2) go to 320
|
||||
go to (290,290,300,310),jlu
|
||||
290 h(1) = huj
|
||||
j1 = 1
|
||||
go to 330
|
||||
300 h(1) = h(1)+huj
|
||||
h(2) = huj*cs(1)
|
||||
h(3) = huj*cs(2)
|
||||
j1 = 3
|
||||
go to 330
|
||||
310 h(1) = h(1)+huj
|
||||
h(2) = h(2)+huj*ratio*cs(1)
|
||||
h(3) = h(3)+huj*ratio*cs(2)
|
||||
h(4) = huj*cs(3)
|
||||
h(5) = huj*cs(4)
|
||||
h(6) = huj*cs(5)
|
||||
j1 = 6
|
||||
go to 330
|
||||
320 if(jlu.gt.nu4 .and. iopt3.ne.0) go to 330
|
||||
do 325 i=1,nvv
|
||||
j1 = j1+1
|
||||
h(j1) = row(i)*huj
|
||||
325 continue
|
||||
330 continue
|
||||
do 335 i=1,iband
|
||||
h(i) = h(i)*wi
|
||||
335 continue
|
||||
c rotate the row into triangle by givens transformations.
|
||||
irot = jrot
|
||||
do 350 i=1,iband
|
||||
irot = irot+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 350
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a(irot,1),co,si)
|
||||
c apply that transformation to the right hand side.
|
||||
call fprota(co,si,zi,f(irot))
|
||||
if(i.eq.iband) go to 360
|
||||
c apply that transformation to the left hand side.
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 340 j=i3,iband
|
||||
i2 = i2+1
|
||||
call fprota(co,si,h(j),a(irot,i2))
|
||||
340 continue
|
||||
350 continue
|
||||
c add the contribution of the row to the sum of squares of residual
|
||||
c right hand sides.
|
||||
360 fp = fp+zi**2
|
||||
c find the number of the next data point in the panel.
|
||||
in = nummer(in)
|
||||
go to 210
|
||||
380 continue
|
||||
c find dmax, the maximum value for the diagonal elements in the reduced
|
||||
c triangle.
|
||||
dmax = 0.
|
||||
do 390 i=1,ncof
|
||||
if(a(i,1).le.dmax) go to 390
|
||||
dmax = a(i,1)
|
||||
390 continue
|
||||
c check whether the observation matrix is rank deficient.
|
||||
sigma = eps*dmax
|
||||
do 400 i=1,ncof
|
||||
if(a(i,1).le.sigma) go to 410
|
||||
400 continue
|
||||
c backward substitution in case of full rank.
|
||||
call fpback(a,f,ncof,iband,c,ncc)
|
||||
rank = ncof
|
||||
do 405 i=1,ncof
|
||||
q(i,1) = a(i,1)/dmax
|
||||
405 continue
|
||||
go to 430
|
||||
c in case of rank deficiency, find the minimum norm solution.
|
||||
410 lwest = ncof*iband+ncof+iband
|
||||
if(lwrk.lt.lwest) go to 925
|
||||
lf = 1
|
||||
lh = lf+ncof
|
||||
la = lh+iband
|
||||
do 420 i=1,ncof
|
||||
ff(i) = f(i)
|
||||
do 420 j=1,iband
|
||||
q(i,j) = a(i,j)
|
||||
420 continue
|
||||
call fprank(q,ff,ncof,iband,ncc,sigma,c,sq,rank,wrk(la),
|
||||
* wrk(lf),wrk(lh))
|
||||
do 425 i=1,ncof
|
||||
q(i,1) = q(i,1)/dmax
|
||||
425 continue
|
||||
c add to the sum of squared residuals, the contribution of reducing
|
||||
c the rank.
|
||||
fp = fp+sq
|
||||
c find the coefficients in the standard b-spline representation of
|
||||
c the spline.
|
||||
430 call fprppo(nu,nv,iopt2,iopt3,cosi,ratio,c,ff,ncoff)
|
||||
c test whether the least-squares spline is an acceptable solution.
|
||||
if(iopt1.lt.0) then
|
||||
if (fp.le.0) go to 970
|
||||
go to 980
|
||||
endif
|
||||
fpms = fp-s
|
||||
if(abs(fpms).le.acc) then
|
||||
if (fp.le.0) go to 970
|
||||
go to 980
|
||||
endif
|
||||
c if f(p=inf) < s, accept the choice of knots.
|
||||
if(fpms.lt.0.) go to 580
|
||||
c test whether we cannot further increase the number of knots
|
||||
if(m.lt.ncof) go to 935
|
||||
c search where to add a new knot.
|
||||
c find for each interval the sum of squared residuals fpint for the
|
||||
c data points having the coordinate belonging to that knot interval.
|
||||
c calculate also coord which is the same sum, weighted by the position
|
||||
c of the data points considered.
|
||||
do 450 i=1,nrint
|
||||
fpint(i) = 0.
|
||||
coord(i) = 0.
|
||||
450 continue
|
||||
do 490 num=1,nreg
|
||||
num1 = num-1
|
||||
lu = num1/nvv
|
||||
l1 = lu+1
|
||||
lv = num1-lu*nvv
|
||||
l2 = lv+1+nuu
|
||||
jrot = lu*nv4+lv
|
||||
in = index(num)
|
||||
460 if(in.eq.0) go to 490
|
||||
store = 0.
|
||||
i1 = jrot
|
||||
do 480 i=1,4
|
||||
hui = spu(in,i)
|
||||
j1 = i1
|
||||
do 470 j=1,4
|
||||
j1 = j1+1
|
||||
store = store+hui*spv(in,j)*c(j1)
|
||||
470 continue
|
||||
i1 = i1+nv4
|
||||
480 continue
|
||||
store = (w(in)*(z(in)-store))**2
|
||||
fpint(l1) = fpint(l1)+store
|
||||
coord(l1) = coord(l1)+store*u(in)
|
||||
fpint(l2) = fpint(l2)+store
|
||||
coord(l2) = coord(l2)+store*v(in)
|
||||
in = nummer(in)
|
||||
go to 460
|
||||
490 continue
|
||||
c bring together the information concerning knot panels which are
|
||||
c symmetric with respect to the origin.
|
||||
do 495 i=1,nrr
|
||||
l1 = nuu+i
|
||||
l2 = l1+nrr
|
||||
fpint(l1) = fpint(l1)+fpint(l2)
|
||||
coord(l1) = coord(l1)+coord(l2)-pi*fpint(l2)
|
||||
495 continue
|
||||
c find the interval for which fpint is maximal on the condition that
|
||||
c there still can be added a knot.
|
||||
l1 = 1
|
||||
l2 = nuu+nrr
|
||||
if(nuest.lt.nu+1) l1=nuu+1
|
||||
if(nvest.lt.nv+2) l2=nuu
|
||||
c test whether we cannot further increase the number of knots.
|
||||
if(l1.gt.l2) go to 950
|
||||
500 fpmax = 0.
|
||||
l = 0
|
||||
do 510 i=l1,l2
|
||||
if(fpmax.ge.fpint(i)) go to 510
|
||||
l = i
|
||||
fpmax = fpint(i)
|
||||
510 continue
|
||||
if(l.eq.0) go to 930
|
||||
c calculate the position of the new knot.
|
||||
arg = coord(l)/fpint(l)
|
||||
c test in what direction the new knot is going to be added.
|
||||
if(l.gt.nuu) go to 530
|
||||
c addition in the u-direction
|
||||
l4 = l+4
|
||||
fpint(l) = 0.
|
||||
fac1 = tu(l4)-arg
|
||||
fac2 = arg-tu(l4-1)
|
||||
if(fac1.gt.(ten*fac2) .or. fac2.gt.(ten*fac1)) go to 500
|
||||
j = nu
|
||||
do 520 i=l4,nu
|
||||
tu(j+1) = tu(j)
|
||||
j = j-1
|
||||
520 continue
|
||||
tu(l4) = arg
|
||||
nu = nu+1
|
||||
go to 570
|
||||
c addition in the v-direction
|
||||
530 l4 = l+4-nuu
|
||||
fpint(l) = 0.
|
||||
fac1 = tv(l4)-arg
|
||||
fac2 = arg-tv(l4-1)
|
||||
if(fac1.gt.(ten*fac2) .or. fac2.gt.(ten*fac1)) go to 500
|
||||
ll = nrr+4
|
||||
j = ll
|
||||
do 550 i=l4,ll
|
||||
tv(j+1) = tv(j)
|
||||
j = j-1
|
||||
550 continue
|
||||
tv(l4) = arg
|
||||
nv = nv+2
|
||||
nrr = nrr+1
|
||||
do 560 i=5,ll
|
||||
j = i+nrr
|
||||
tv(j) = tv(i)+pi
|
||||
560 continue
|
||||
c restart the computations with the new set of knots.
|
||||
570 continue
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 2: determination of the smoothing bicubic spline. c
|
||||
c ****************************************************** c
|
||||
c we have determined the number of knots and their position. we now c
|
||||
c compute the coefficients of the smoothing spline sp(u,v). c
|
||||
c the observation matrix a is extended by the rows of a matrix, expres-c
|
||||
c sing that sp(u,v) must be a constant function in the variable c
|
||||
c v and a cubic polynomial in the variable u. the corresponding c
|
||||
c weights of these additional rows are set to 1/(p). iteratively c
|
||||
c we than have to determine the value of p such that f(p) = sum((w(i)* c
|
||||
c (z(i)-sp(u(i),v(i))))**2) be = s. c
|
||||
c we already know that the least-squares polynomial corresponds to p=0,c
|
||||
c and that the least-squares bicubic spline corresponds to p=infin. c
|
||||
c the iteration process makes use of rational interpolation. since f(p)c
|
||||
c is a convex and strictly decreasing function of p, it can be approx- c
|
||||
c imated by a rational function of the form r(p) = (u*p+v)/(p+w). c
|
||||
c three values of p (p1,p2,p3) with corresponding values of f(p) (f1= c
|
||||
c f(p1)-s,f2=f(p2)-s,f3=f(p3)-s) are used to calculate the new value c
|
||||
c of p such that r(p)=s. convergence is guaranteed by taking f1>0,f3<0.c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c evaluate the discontinuity jumps of the 3-th order derivative of
|
||||
c the b-splines at the knots tu(l),l=5,...,nu-4.
|
||||
580 call fpdisc(tu,nu,5,bu,nuest)
|
||||
c evaluate the discontinuity jumps of the 3-th order derivative of
|
||||
c the b-splines at the knots tv(l),l=5,...,nv-4.
|
||||
call fpdisc(tv,nv,5,bv,nvest)
|
||||
c initial value for p.
|
||||
p1 = 0.
|
||||
f1 = sup-s
|
||||
p3 = -one
|
||||
f3 = fpms
|
||||
p = 0.
|
||||
do 590 i=1,ncof
|
||||
p = p+a(i,1)
|
||||
590 continue
|
||||
rn = ncof
|
||||
p = rn/p
|
||||
c find the bandwidth of the extended observation matrix.
|
||||
iband4 = iband+ipar1
|
||||
if(iband4.gt.ncof) iband4 = ncof
|
||||
iband3 = iband4 -1
|
||||
ich1 = 0
|
||||
ich3 = 0
|
||||
nuu = nu4-iopt3-1
|
||||
c iteration process to find the root of f(p)=s.
|
||||
do 920 iter=1,maxit
|
||||
pinv = one/p
|
||||
c store the triangularized observation matrix into q.
|
||||
do 630 i=1,ncof
|
||||
ff(i) = f(i)
|
||||
do 620 j=1,iband4
|
||||
q(i,j) = 0.
|
||||
620 continue
|
||||
do 630 j=1,iband
|
||||
q(i,j) = a(i,j)
|
||||
630 continue
|
||||
c extend the observation matrix with the rows of a matrix, expressing
|
||||
c that for u=constant sp(u,v) must be a constant function.
|
||||
do 720 i=5,nv4
|
||||
ii = i-4
|
||||
do 635 l=1,nvv
|
||||
row(l) = 0.
|
||||
635 continue
|
||||
ll = ii
|
||||
do 640 l=1,5
|
||||
if(ll.gt.nvv) ll=1
|
||||
row(ll) = row(ll)+bv(ii,l)
|
||||
ll = ll+1
|
||||
640 continue
|
||||
do 720 j=1,nuu
|
||||
c initialize the new row.
|
||||
do 645 l=1,iband
|
||||
h(l) = 0.
|
||||
645 continue
|
||||
c fill in the non-zero elements of the row. jrot records the column
|
||||
c number of the first non-zero element in the row.
|
||||
if(j.gt.iopt2) go to 665
|
||||
if(j.eq.2) go to 655
|
||||
do 650 k=1,2
|
||||
cs(k) = 0.
|
||||
do 650 l=1,nvv
|
||||
cs(k) = cs(k)+cosi(k,l)*row(l)
|
||||
650 continue
|
||||
h(1) = cs(1)
|
||||
h(2) = cs(2)
|
||||
jrot = 2
|
||||
go to 675
|
||||
655 do 660 k=3,5
|
||||
cs(k) = 0.
|
||||
do 660 l=1,nvv
|
||||
cs(k) = cs(k)+cosi(k,l)*row(l)
|
||||
660 continue
|
||||
h(1) = cs(1)*ratio
|
||||
h(2) = cs(2)*ratio
|
||||
h(3) = cs(3)
|
||||
h(4) = cs(4)
|
||||
h(5) = cs(5)
|
||||
jrot = 2
|
||||
go to 675
|
||||
665 do 670 l=1,nvv
|
||||
h(l) = row(l)
|
||||
670 continue
|
||||
jrot = ipar1+1+(j-iopt2-1)*nvv
|
||||
675 do 677 l=1,iband
|
||||
h(l) = h(l)*pinv
|
||||
677 continue
|
||||
zi = 0.
|
||||
c rotate the new row into triangle by givens transformations.
|
||||
do 710 irot=jrot,ncof
|
||||
piv = h(1)
|
||||
i2 = min0(iband1,ncof-irot)
|
||||
if(piv.eq.0.) then
|
||||
if (i2.le.0) go to 720
|
||||
go to 690
|
||||
endif
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,q(irot,1),co,si)
|
||||
c apply that givens transformation to the right hand side.
|
||||
call fprota(co,si,zi,ff(irot))
|
||||
if(i2.eq.0) go to 720
|
||||
c apply that givens transformation to the left hand side.
|
||||
do 680 l=1,i2
|
||||
l1 = l+1
|
||||
call fprota(co,si,h(l1),q(irot,l1))
|
||||
680 continue
|
||||
690 do 700 l=1,i2
|
||||
h(l) = h(l+1)
|
||||
700 continue
|
||||
h(i2+1) = 0.
|
||||
710 continue
|
||||
720 continue
|
||||
c extend the observation matrix with the rows of a matrix expressing
|
||||
c that for v=constant. sp(u,v) must be a cubic polynomial.
|
||||
do 810 i=5,nu4
|
||||
ii = i-4
|
||||
do 810 j=1,nvv
|
||||
c initialize the new row
|
||||
do 730 l=1,iband4
|
||||
h(l) = 0.
|
||||
730 continue
|
||||
c fill in the non-zero elements of the row. jrot records the column
|
||||
c number of the first non-zero element in the row.
|
||||
j1 = 1
|
||||
do 760 l=1,5
|
||||
il = ii+l-1
|
||||
if(il.eq.nu4 .and. iopt3.ne.0) go to 760
|
||||
if(il.gt.iopt2+1) go to 750
|
||||
go to (735,740,745),il
|
||||
735 h(1) = bu(ii,l)
|
||||
j1 = j+1
|
||||
go to 760
|
||||
740 h(1) = h(1)+bu(ii,l)
|
||||
h(2) = bu(ii,l)*cosi(1,j)
|
||||
h(3) = bu(ii,l)*cosi(2,j)
|
||||
j1 = j+3
|
||||
go to 760
|
||||
745 h(1) = h(1)+bu(ii,l)
|
||||
h(2) = bu(ii,l)*cosi(1,j)*ratio
|
||||
h(3) = bu(ii,l)*cosi(2,j)*ratio
|
||||
h(4) = bu(ii,l)*cosi(3,j)
|
||||
h(5) = bu(ii,l)*cosi(4,j)
|
||||
h(6) = bu(ii,l)*cosi(5,j)
|
||||
j1 = j+6
|
||||
go to 760
|
||||
750 h(j1) = bu(ii,l)
|
||||
j1 = j1+nvv
|
||||
760 continue
|
||||
do 765 l=1,iband4
|
||||
h(l) = h(l)*pinv
|
||||
765 continue
|
||||
zi = 0.
|
||||
jrot = 1
|
||||
if(ii.gt.iopt2+1) jrot = ipar1+(ii-iopt2-2)*nvv+j
|
||||
c rotate the new row into triangle by givens transformations.
|
||||
do 800 irot=jrot,ncof
|
||||
piv = h(1)
|
||||
i2 = min0(iband3,ncof-irot)
|
||||
if(piv.eq.0.) then
|
||||
if (i2.le.0) go to 810
|
||||
go to 780
|
||||
endif
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,q(irot,1),co,si)
|
||||
c apply that givens transformation to the right hand side.
|
||||
call fprota(co,si,zi,ff(irot))
|
||||
if(i2.eq.0) go to 810
|
||||
c apply that givens transformation to the left hand side.
|
||||
do 770 l=1,i2
|
||||
l1 = l+1
|
||||
call fprota(co,si,h(l1),q(irot,l1))
|
||||
770 continue
|
||||
780 do 790 l=1,i2
|
||||
h(l) = h(l+1)
|
||||
790 continue
|
||||
h(i2+1) = 0.
|
||||
800 continue
|
||||
810 continue
|
||||
c find dmax, the maximum value for the diagonal elements in the
|
||||
c reduced triangle.
|
||||
dmax = 0.
|
||||
do 820 i=1,ncof
|
||||
if(q(i,1).le.dmax) go to 820
|
||||
dmax = q(i,1)
|
||||
820 continue
|
||||
c check whether the matrix is rank deficient.
|
||||
sigma = eps*dmax
|
||||
do 830 i=1,ncof
|
||||
if(q(i,1).le.sigma) go to 840
|
||||
830 continue
|
||||
c backward substitution in case of full rank.
|
||||
call fpback(q,ff,ncof,iband4,c,ncc)
|
||||
rank = ncof
|
||||
go to 845
|
||||
c in case of rank deficiency, find the minimum norm solution.
|
||||
840 lwest = ncof*iband4+ncof+iband4
|
||||
if(lwrk.lt.lwest) go to 925
|
||||
lf = 1
|
||||
lh = lf+ncof
|
||||
la = lh+iband4
|
||||
call fprank(q,ff,ncof,iband4,ncc,sigma,c,sq,rank,wrk(la),
|
||||
* wrk(lf),wrk(lh))
|
||||
845 do 850 i=1,ncof
|
||||
q(i,1) = q(i,1)/dmax
|
||||
850 continue
|
||||
c find the coefficients in the standard b-spline representation of
|
||||
c the polar spline.
|
||||
call fprppo(nu,nv,iopt2,iopt3,cosi,ratio,c,ff,ncoff)
|
||||
c compute f(p).
|
||||
fp = 0.
|
||||
do 890 num = 1,nreg
|
||||
num1 = num-1
|
||||
lu = num1/nvv
|
||||
lv = num1-lu*nvv
|
||||
jrot = lu*nv4+lv
|
||||
in = index(num)
|
||||
860 if(in.eq.0) go to 890
|
||||
store = 0.
|
||||
i1 = jrot
|
||||
do 880 i=1,4
|
||||
hui = spu(in,i)
|
||||
j1 = i1
|
||||
do 870 j=1,4
|
||||
j1 = j1+1
|
||||
store = store+hui*spv(in,j)*c(j1)
|
||||
870 continue
|
||||
i1 = i1+nv4
|
||||
880 continue
|
||||
fp = fp+(w(in)*(z(in)-store))**2
|
||||
in = nummer(in)
|
||||
go to 860
|
||||
890 continue
|
||||
c test whether the approximation sp(u,v) is an acceptable solution
|
||||
fpms = fp-s
|
||||
if(abs(fpms).le.acc) go to 980
|
||||
c test whether the maximum allowable number of iterations has been
|
||||
c reached.
|
||||
if(iter.eq.maxit) go to 940
|
||||
c carry out one more step of the iteration process.
|
||||
p2 = p
|
||||
f2 = fpms
|
||||
if(ich3.ne.0) go to 900
|
||||
if((f2-f3).gt.acc) go to 895
|
||||
c our initial choice of p is too large.
|
||||
p3 = p2
|
||||
f3 = f2
|
||||
p = p*con4
|
||||
if(p.le.p1) p = p1*con9 + p2*con1
|
||||
go to 920
|
||||
895 if(f2.lt.0.) ich3 = 1
|
||||
900 if(ich1.ne.0) go to 910
|
||||
if((f1-f2).gt.acc) go to 905
|
||||
c our initial choice of p is too small
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
p = p/con4
|
||||
if(p3.lt.0.) go to 920
|
||||
if(p.ge.p3) p = p2*con1 +p3*con9
|
||||
go to 920
|
||||
905 if(f2.gt.0.) ich1 = 1
|
||||
c test whether the iteration process proceeds as theoretically
|
||||
c expected.
|
||||
910 if(f2.ge.f1 .or. f2.le.f3) go to 945
|
||||
c find the new value of p.
|
||||
p = fprati(p1,f1,p2,f2,p3,f3)
|
||||
920 continue
|
||||
c error codes and messages.
|
||||
925 ier = lwest
|
||||
go to 990
|
||||
930 ier = 5
|
||||
go to 990
|
||||
935 ier = 4
|
||||
go to 990
|
||||
940 ier = 3
|
||||
go to 990
|
||||
945 ier = 2
|
||||
go to 990
|
||||
950 ier = 1
|
||||
go to 990
|
||||
960 ier = -2
|
||||
go to 990
|
||||
970 ier = -1
|
||||
fp = 0.
|
||||
980 if(ncof.ne.rank) ier = -rank
|
||||
990 return
|
||||
end
|
||||
|
||||
237
cxx/fitpack/fprank.f
Normal file
237
cxx/fitpack/fprank.f
Normal file
@ -0,0 +1,237 @@
|
||||
recursive subroutine fprank(a,f,n,m,na,tol,c,sq,rank,aa,ff,h)
|
||||
implicit none
|
||||
c subroutine fprank finds the minimum norm solution of a least-
|
||||
c squares problem in case of rank deficiency.
|
||||
c
|
||||
c input parameters:
|
||||
c a : array, which contains the non-zero elements of the observation
|
||||
c matrix after triangularization by givens transformations.
|
||||
c f : array, which contains the transformed right hand side.
|
||||
c n : integer,which contains the dimension of a.
|
||||
c m : integer, which denotes the bandwidth of a.
|
||||
c tol : real value, giving a threshold to determine the rank of a.
|
||||
c
|
||||
c output parameters:
|
||||
c c : array, which contains the minimum norm solution.
|
||||
c sq : real value, giving the contribution of reducing the rank
|
||||
c to the sum of squared residuals.
|
||||
c rank : integer, which contains the rank of matrix a.
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer n,m,na,rank
|
||||
real*8 tol,sq
|
||||
c ..array arguments..
|
||||
real*8 a(na,m),f(n),c(n),aa(n,m),ff(n),h(m)
|
||||
c ..local scalars..
|
||||
integer i,ii,ij,i1,i2,j,jj,j1,j2,j3,k,kk,m1,nl
|
||||
real*8 cos,fac,piv,sin,yi
|
||||
double precision store,stor1,stor2,stor3
|
||||
c ..function references..
|
||||
integer min0
|
||||
c ..subroutine references..
|
||||
c fpgivs,fprota
|
||||
c ..
|
||||
m1 = m-1
|
||||
c the rank deficiency nl is considered to be the number of sufficient
|
||||
c small diagonal elements of a.
|
||||
nl = 0
|
||||
sq = 0.
|
||||
do 90 i=1,n
|
||||
if(a(i,1).gt.tol) go to 90
|
||||
c if a sufficient small diagonal element is found, we put it to
|
||||
c zero. the remainder of the row corresponding to that zero diagonal
|
||||
c element is then rotated into triangle by givens rotations .
|
||||
c the rank deficiency is increased by one.
|
||||
nl = nl+1
|
||||
if(i.eq.n) go to 90
|
||||
yi = f(i)
|
||||
do 10 j=1,m1
|
||||
h(j) = a(i,j+1)
|
||||
10 continue
|
||||
h(m) = 0.
|
||||
i1 = i+1
|
||||
do 60 ii=i1,n
|
||||
i2 = min0(n-ii,m1)
|
||||
piv = h(1)
|
||||
if(piv.eq.0.) go to 30
|
||||
call fpgivs(piv,a(ii,1),cos,sin)
|
||||
call fprota(cos,sin,yi,f(ii))
|
||||
if(i2.eq.0) go to 70
|
||||
do 20 j=1,i2
|
||||
j1 = j+1
|
||||
call fprota(cos,sin,h(j1),a(ii,j1))
|
||||
h(j) = h(j1)
|
||||
20 continue
|
||||
go to 50
|
||||
30 if(i2.eq.0) go to 70
|
||||
do 40 j=1,i2
|
||||
h(j) = h(j+1)
|
||||
40 continue
|
||||
50 h(i2+1) = 0.
|
||||
60 continue
|
||||
c add to the sum of squared residuals the contribution of deleting
|
||||
c the row with small diagonal element.
|
||||
70 sq = sq+yi**2
|
||||
90 continue
|
||||
c rank denotes the rank of a.
|
||||
rank = n-nl
|
||||
c let b denote the (rank*n) upper trapezoidal matrix which can be
|
||||
c obtained from the (n*n) upper triangular matrix a by deleting
|
||||
c the rows and interchanging the columns corresponding to a zero
|
||||
c diagonal element. if this matrix is factorized using givens
|
||||
c transformations as b = (r) (u) where
|
||||
c r is a (rank*rank) upper triangular matrix,
|
||||
c u is a (rank*n) orthonormal matrix
|
||||
c then the minimal least-squares solution c is given by c = b' v,
|
||||
c where v is the solution of the system (r) (r)' v = g and
|
||||
c g denotes the vector obtained from the old right hand side f, by
|
||||
c removing the elements corresponding to a zero diagonal element of a.
|
||||
c initialization.
|
||||
do 100 i=1,rank
|
||||
do 100 j=1,m
|
||||
aa(i,j) = 0.
|
||||
100 continue
|
||||
c form in aa the upper triangular matrix obtained from a by
|
||||
c removing rows and columns with zero diagonal elements. form in ff
|
||||
c the new right hand side by removing the elements of the old right
|
||||
c hand side corresponding to a deleted row.
|
||||
ii = 0
|
||||
do 120 i=1,n
|
||||
if(a(i,1).le.tol) go to 120
|
||||
ii = ii+1
|
||||
ff(ii) = f(i)
|
||||
aa(ii,1) = a(i,1)
|
||||
jj = ii
|
||||
kk = 1
|
||||
j = i
|
||||
j1 = min0(j-1,m1)
|
||||
if(j1.eq.0) go to 120
|
||||
do 110 k=1,j1
|
||||
j = j-1
|
||||
if(a(j,1).le.tol) go to 110
|
||||
kk = kk+1
|
||||
jj = jj-1
|
||||
aa(jj,kk) = a(j,k+1)
|
||||
110 continue
|
||||
120 continue
|
||||
c form successively in h the columns of a with a zero diagonal element.
|
||||
ii = 0
|
||||
do 200 i=1,n
|
||||
ii = ii+1
|
||||
if(a(i,1).gt.tol) go to 200
|
||||
ii = ii-1
|
||||
if(ii.eq.0) go to 200
|
||||
jj = 1
|
||||
j = i
|
||||
j1 = min0(j-1,m1)
|
||||
do 130 k=1,j1
|
||||
j = j-1
|
||||
if(a(j,1).le.tol) go to 130
|
||||
h(jj) = a(j,k+1)
|
||||
jj = jj+1
|
||||
130 continue
|
||||
do 140 kk=jj,m
|
||||
h(kk) = 0.
|
||||
140 continue
|
||||
c rotate this column into aa by givens transformations.
|
||||
jj = ii
|
||||
do 190 i1=1,ii
|
||||
j1 = min0(jj-1,m1)
|
||||
piv = h(1)
|
||||
if(piv.ne.0.) go to 160
|
||||
if(j1.eq.0) go to 200
|
||||
do 150 j2=1,j1
|
||||
j3 = j2+1
|
||||
h(j2) = h(j3)
|
||||
150 continue
|
||||
go to 180
|
||||
160 call fpgivs(piv,aa(jj,1),cos,sin)
|
||||
if(j1.eq.0) go to 200
|
||||
kk = jj
|
||||
do 170 j2=1,j1
|
||||
j3 = j2+1
|
||||
kk = kk-1
|
||||
call fprota(cos,sin,h(j3),aa(kk,j3))
|
||||
h(j2) = h(j3)
|
||||
170 continue
|
||||
180 jj = jj-1
|
||||
h(j3) = 0.
|
||||
190 continue
|
||||
200 continue
|
||||
c solve the system (aa) (f1) = ff
|
||||
ff(rank) = ff(rank)/aa(rank,1)
|
||||
i = rank-1
|
||||
if(i.eq.0) go to 230
|
||||
do 220 j=2,rank
|
||||
store = ff(i)
|
||||
i1 = min0(j-1,m1)
|
||||
k = i
|
||||
do 210 ii=1,i1
|
||||
k = k+1
|
||||
stor1 = ff(k)
|
||||
stor2 = aa(i,ii+1)
|
||||
store = store-stor1*stor2
|
||||
210 continue
|
||||
stor1 = aa(i,1)
|
||||
ff(i) = store/stor1
|
||||
i = i-1
|
||||
220 continue
|
||||
c solve the system (aa)' (f2) = f1
|
||||
230 ff(1) = ff(1)/aa(1,1)
|
||||
if(rank.eq.1) go to 260
|
||||
do 250 j=2,rank
|
||||
store = ff(j)
|
||||
i1 = min0(j-1,m1)
|
||||
k = j
|
||||
do 240 ii=1,i1
|
||||
k = k-1
|
||||
stor1 = ff(k)
|
||||
stor2 = aa(k,ii+1)
|
||||
store = store-stor1*stor2
|
||||
240 continue
|
||||
stor1 = aa(j,1)
|
||||
ff(j) = store/stor1
|
||||
250 continue
|
||||
c premultiply f2 by the transpoze of a.
|
||||
260 k = 0
|
||||
do 280 i=1,n
|
||||
store = 0.
|
||||
if(a(i,1).gt.tol) k = k+1
|
||||
j1 = min0(i,m)
|
||||
kk = k
|
||||
ij = i+1
|
||||
do 270 j=1,j1
|
||||
ij = ij-1
|
||||
if(a(ij,1).le.tol) go to 270
|
||||
stor1 = a(ij,j)
|
||||
stor2 = ff(kk)
|
||||
store = store+stor1*stor2
|
||||
kk = kk-1
|
||||
270 continue
|
||||
c(i) = store
|
||||
280 continue
|
||||
c add to the sum of squared residuals the contribution of putting
|
||||
c to zero the small diagonal elements of matrix (a).
|
||||
stor3 = 0.
|
||||
do 310 i=1,n
|
||||
if(a(i,1).gt.tol) go to 310
|
||||
store = f(i)
|
||||
i1 = min0(n-i,m1)
|
||||
if(i1.eq.0) go to 300
|
||||
do 290 j=1,i1
|
||||
ij = i+j
|
||||
stor1 = c(ij)
|
||||
stor2 = a(i,j+1)
|
||||
store = store-stor1*stor2
|
||||
290 continue
|
||||
300 fac = a(i,1)*c(i)
|
||||
stor1 = a(i,1)
|
||||
stor2 = c(i)
|
||||
stor1 = stor1*stor2
|
||||
stor3 = stor3+stor1*(stor1-store-store)
|
||||
310 continue
|
||||
fac = stor3
|
||||
sq = sq+fac
|
||||
return
|
||||
end
|
||||
|
||||
31
cxx/fitpack/fprati.f
Normal file
31
cxx/fitpack/fprati.f
Normal file
@ -0,0 +1,31 @@
|
||||
recursive function fprati(p1,f1,p2,f2,p3,f3) result(fprati_res)
|
||||
implicit none
|
||||
real*8 :: fprati_res
|
||||
c given three points (p1,f1),(p2,f2) and (p3,f3), function fprati
|
||||
c gives the value of p such that the rational interpolating function
|
||||
c of the form r(p) = (u*p+v)/(p+w) equals zero at p.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 p1,f1,p2,f2,p3,f3
|
||||
c ..local scalars..
|
||||
real*8 h1,h2,h3,p
|
||||
c ..
|
||||
if(p3.gt.0.) go to 10
|
||||
c value of p in case p3 = infinity.
|
||||
p = (p1*(f1-f3)*f2-p2*(f2-f3)*f1)/((f1-f2)*f3)
|
||||
go to 20
|
||||
c value of p in case p3 ^= infinity.
|
||||
10 h1 = f1*(f2-f3)
|
||||
h2 = f2*(f3-f1)
|
||||
h3 = f3*(f1-f2)
|
||||
p = -(p1*p2*h3+p2*p3*h1+p3*p1*h2)/(p1*h1+p2*h2+p3*h3)
|
||||
c adjust the value of p1,f1,p3 and f3 such that f1 > 0 and f3 < 0.
|
||||
20 if(f2.lt.0.) go to 30
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
go to 40
|
||||
30 p3 = p2
|
||||
f3 = f2
|
||||
40 fprati_res = p
|
||||
return
|
||||
end
|
||||
368
cxx/fitpack/fpregr.f
Normal file
368
cxx/fitpack/fpregr.f
Normal file
@ -0,0 +1,368 @@
|
||||
recursive subroutine fpregr(iopt,x,mx,y,my,z,mz,xb,xe,yb,ye,
|
||||
* kx,ky,s,nxest,nyest,tol,maxit,nc,nx,tx,ny,ty,c,fp,fp0,fpold,
|
||||
* reducx,reducy,fpintx,fpinty,lastdi,nplusx,nplusy,nrx,nry,
|
||||
* nrdatx,nrdaty,wrk,lwrk,ier)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 xb,xe,yb,ye,s,tol,fp,fp0,fpold,reducx,reducy
|
||||
integer iopt,mx,my,mz,kx,ky,nxest,nyest,maxit,nc,nx,ny,lastdi,
|
||||
* nplusx,nplusy,lwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 x(mx),y(my),z(mz),tx(nxest),ty(nyest),c(nc),fpintx(nxest),
|
||||
* fpinty(nyest),wrk(lwrk)
|
||||
integer nrdatx(nxest),nrdaty(nyest),nrx(mx),nry(my)
|
||||
c ..local scalars
|
||||
real*8 acc,fpms,f1,f2,f3,p,p1,p2,p3,rn,one,half,con1,con9,con4
|
||||
integer i,ich1,ich3,ifbx,ifby,ifsx,ifsy,iter,j,kx1,kx2,ky1,ky2,
|
||||
* k3,l,lax,lay,lbx,lby,lq,lri,lsx,lsy,mk1,mm,mpm,mynx,ncof,
|
||||
* nk1x,nk1y,nmaxx,nmaxy,nminx,nminy,nplx,nply,npl1,nrintx,
|
||||
* nrinty,nxe,nxk,nye
|
||||
c ..function references..
|
||||
real*8 abs,fprati
|
||||
integer max0,min0
|
||||
c ..subroutine references..
|
||||
c fpgrre,fpknot
|
||||
c ..
|
||||
c set constants
|
||||
one = 1
|
||||
half = 0.5e0
|
||||
con1 = 0.1e0
|
||||
con9 = 0.9e0
|
||||
con4 = 0.4e-01
|
||||
c we partition the working space.
|
||||
kx1 = kx+1
|
||||
ky1 = ky+1
|
||||
kx2 = kx1+1
|
||||
ky2 = ky1+1
|
||||
lsx = 1
|
||||
lsy = lsx+mx*kx1
|
||||
lri = lsy+my*ky1
|
||||
mm = max0(nxest,my)
|
||||
lq = lri+mm
|
||||
mynx = nxest*my
|
||||
lax = lq+mynx
|
||||
nxk = nxest*kx2
|
||||
lbx = lax+nxk
|
||||
lay = lbx+nxk
|
||||
lby = lay+nyest*ky2
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 1: determination of the number of knots and their position. c
|
||||
c **************************************************************** c
|
||||
c given a set of knots we compute the least-squares spline sinf(x,y), c
|
||||
c and the corresponding sum of squared residuals fp=f(p=inf). c
|
||||
c if iopt=-1 sinf(x,y) is the requested approximation. c
|
||||
c if iopt=0 or iopt=1 we check whether we can accept the knots: c
|
||||
c if fp <=s we will continue with the current set of knots. c
|
||||
c if fp > s we will increase the number of knots and compute the c
|
||||
c corresponding least-squares spline until finally fp<=s. c
|
||||
c the initial choice of knots depends on the value of s and iopt. c
|
||||
c if s=0 we have spline interpolation; in that case the number of c
|
||||
c knots equals nmaxx = mx+kx+1 and nmaxy = my+ky+1. c
|
||||
c if s>0 and c
|
||||
c *iopt=0 we first compute the least-squares polynomial of degree c
|
||||
c kx in x and ky in y; nx=nminx=2*kx+2 and ny=nymin=2*ky+2. c
|
||||
c *iopt=1 we start with the knots found at the last call of the c
|
||||
c routine, except for the case that s > fp0; then we can compute c
|
||||
c the least-squares polynomial directly. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c determine the number of knots for polynomial approximation.
|
||||
nminx = 2*kx1
|
||||
nminy = 2*ky1
|
||||
if(iopt.lt.0) go to 120
|
||||
c acc denotes the absolute tolerance for the root of f(p)=s.
|
||||
acc = tol*s
|
||||
c find nmaxx and nmaxy which denote the number of knots in x- and y-
|
||||
c direction in case of spline interpolation.
|
||||
nmaxx = mx+kx1
|
||||
nmaxy = my+ky1
|
||||
c find nxe and nye which denote the maximum number of knots
|
||||
c allowed in each direction
|
||||
nxe = min0(nmaxx,nxest)
|
||||
nye = min0(nmaxy,nyest)
|
||||
if(s.gt.0.) go to 100
|
||||
c if s = 0, s(x,y) is an interpolating spline.
|
||||
nx = nmaxx
|
||||
ny = nmaxy
|
||||
c test whether the required storage space exceeds the available one.
|
||||
if(ny.gt.nyest .or. nx.gt.nxest) go to 420
|
||||
c find the position of the interior knots in case of interpolation.
|
||||
c the knots in the x-direction.
|
||||
mk1 = mx-kx1
|
||||
if(mk1.eq.0) go to 60
|
||||
k3 = kx/2
|
||||
i = kx1+1
|
||||
j = k3+2
|
||||
if(k3*2.eq.kx) go to 40
|
||||
do 30 l=1,mk1
|
||||
tx(i) = x(j)
|
||||
i = i+1
|
||||
j = j+1
|
||||
30 continue
|
||||
go to 60
|
||||
40 do 50 l=1,mk1
|
||||
tx(i) = (x(j)+x(j-1))*half
|
||||
i = i+1
|
||||
j = j+1
|
||||
50 continue
|
||||
c the knots in the y-direction.
|
||||
60 mk1 = my-ky1
|
||||
if(mk1.eq.0) go to 120
|
||||
k3 = ky/2
|
||||
i = ky1+1
|
||||
j = k3+2
|
||||
if(k3*2.eq.ky) go to 80
|
||||
do 70 l=1,mk1
|
||||
ty(i) = y(j)
|
||||
i = i+1
|
||||
j = j+1
|
||||
70 continue
|
||||
go to 120
|
||||
80 do 90 l=1,mk1
|
||||
ty(i) = (y(j)+y(j-1))*half
|
||||
i = i+1
|
||||
j = j+1
|
||||
90 continue
|
||||
go to 120
|
||||
c if s > 0 our initial choice of knots depends on the value of iopt.
|
||||
100 if(iopt.eq.0) go to 115
|
||||
if(fp0.le.s) go to 115
|
||||
c if iopt=1 and fp0 > s we start computing the least- squares spline
|
||||
c according to the set of knots found at the last call of the routine.
|
||||
c we determine the number of grid coordinates x(i) inside each knot
|
||||
c interval (tx(l),tx(l+1)).
|
||||
l = kx2
|
||||
j = 1
|
||||
nrdatx(1) = 0
|
||||
mpm = mx-1
|
||||
do 105 i=2,mpm
|
||||
nrdatx(j) = nrdatx(j)+1
|
||||
if(x(i).lt.tx(l)) go to 105
|
||||
nrdatx(j) = nrdatx(j)-1
|
||||
l = l+1
|
||||
j = j+1
|
||||
nrdatx(j) = 0
|
||||
105 continue
|
||||
c we determine the number of grid coordinates y(i) inside each knot
|
||||
c interval (ty(l),ty(l+1)).
|
||||
l = ky2
|
||||
j = 1
|
||||
nrdaty(1) = 0
|
||||
mpm = my-1
|
||||
do 110 i=2,mpm
|
||||
nrdaty(j) = nrdaty(j)+1
|
||||
if(y(i).lt.ty(l)) go to 110
|
||||
nrdaty(j) = nrdaty(j)-1
|
||||
l = l+1
|
||||
j = j+1
|
||||
nrdaty(j) = 0
|
||||
110 continue
|
||||
go to 120
|
||||
c if iopt=0 or iopt=1 and s>=fp0, we start computing the least-squares
|
||||
c polynomial of degree kx in x and ky in y (which is a spline without
|
||||
c interior knots).
|
||||
115 nx = nminx
|
||||
ny = nminy
|
||||
nrdatx(1) = mx-2
|
||||
nrdaty(1) = my-2
|
||||
lastdi = 0
|
||||
nplusx = 0
|
||||
nplusy = 0
|
||||
fp0 = 0.
|
||||
fpold = 0.
|
||||
reducx = 0.
|
||||
reducy = 0.
|
||||
120 mpm = mx+my
|
||||
ifsx = 0
|
||||
ifsy = 0
|
||||
ifbx = 0
|
||||
ifby = 0
|
||||
p = -one
|
||||
c main loop for the different sets of knots.mpm=mx+my is a save upper
|
||||
c bound for the number of trials.
|
||||
do 250 iter=1,mpm
|
||||
if(nx.eq.nminx .and. ny.eq.nminy) ier = -2
|
||||
c find nrintx (nrinty) which is the number of knot intervals in the
|
||||
c x-direction (y-direction).
|
||||
nrintx = nx-nminx+1
|
||||
nrinty = ny-nminy+1
|
||||
c find ncof, the number of b-spline coefficients for the current set
|
||||
c of knots.
|
||||
nk1x = nx-kx1
|
||||
nk1y = ny-ky1
|
||||
ncof = nk1x*nk1y
|
||||
c find the position of the additional knots which are needed for the
|
||||
c b-spline representation of s(x,y).
|
||||
i = nx
|
||||
do 130 j=1,kx1
|
||||
tx(j) = xb
|
||||
tx(i) = xe
|
||||
i = i-1
|
||||
130 continue
|
||||
i = ny
|
||||
do 140 j=1,ky1
|
||||
ty(j) = yb
|
||||
ty(i) = ye
|
||||
i = i-1
|
||||
140 continue
|
||||
c find the least-squares spline sinf(x,y) and calculate for each knot
|
||||
c interval tx(j+kx)<=x<=tx(j+kx+1) (ty(j+ky)<=y<=ty(j+ky+1)) the sum
|
||||
c of squared residuals fpintx(j),j=1,2,...,nx-2*kx-1 (fpinty(j),j=1,2,
|
||||
c ...,ny-2*ky-1) for the data points having their absciss (ordinate)-
|
||||
c value belonging to that interval.
|
||||
c fp gives the total sum of squared residuals.
|
||||
call fpgrre(ifsx,ifsy,ifbx,ifby,x,mx,y,my,z,mz,kx,ky,tx,nx,ty,
|
||||
* ny,p,c,nc,fp,fpintx,fpinty,mm,mynx,kx1,kx2,ky1,ky2,wrk(lsx),
|
||||
* wrk(lsy),wrk(lri),wrk(lq),wrk(lax),wrk(lay),wrk(lbx),wrk(lby),
|
||||
* nrx,nry)
|
||||
if(ier.eq.(-2)) fp0 = fp
|
||||
c test whether the least-squares spline is an acceptable solution.
|
||||
if(iopt.lt.0) go to 440
|
||||
fpms = fp-s
|
||||
if(abs(fpms) .lt. acc) go to 440
|
||||
c if f(p=inf) < s, we accept the choice of knots.
|
||||
if(fpms.lt.0.) go to 300
|
||||
c if nx=nmaxx and ny=nmaxy, sinf(x,y) is an interpolating spline.
|
||||
if(nx.eq.nmaxx .and. ny.eq.nmaxy) go to 430
|
||||
c increase the number of knots.
|
||||
c if nx=nxe and ny=nye we cannot further increase the number of knots
|
||||
c because of the storage capacity limitation.
|
||||
if(nx.eq.nxe .and. ny.eq.nye) go to 420
|
||||
ier = 0
|
||||
c adjust the parameter reducx or reducy according to the direction
|
||||
c in which the last added knots were located.
|
||||
if (lastdi.lt.0) go to 150
|
||||
if (lastdi.eq.0) go to 170
|
||||
go to 160
|
||||
150 reducx = fpold-fp
|
||||
go to 170
|
||||
160 reducy = fpold-fp
|
||||
c store the sum of squared residuals for the current set of knots.
|
||||
170 fpold = fp
|
||||
c find nplx, the number of knots we should add in the x-direction.
|
||||
nplx = 1
|
||||
if(nx.eq.nminx) go to 180
|
||||
npl1 = nplusx*2
|
||||
rn = nplusx
|
||||
if(reducx.gt.acc) npl1 = rn*fpms/reducx
|
||||
nplx = min0(nplusx*2,max0(npl1,nplusx/2,1))
|
||||
c find nply, the number of knots we should add in the y-direction.
|
||||
180 nply = 1
|
||||
if(ny.eq.nminy) go to 190
|
||||
npl1 = nplusy*2
|
||||
rn = nplusy
|
||||
if(reducy.gt.acc) npl1 = rn*fpms/reducy
|
||||
nply = min0(nplusy*2,max0(npl1,nplusy/2,1))
|
||||
190 if (nplx.lt.nply) go to 210
|
||||
if (nplx.eq.nply) go to 200
|
||||
go to 230
|
||||
200 if(lastdi.lt.0) go to 230
|
||||
210 if(nx.eq.nxe) go to 230
|
||||
c addition in the x-direction.
|
||||
lastdi = -1
|
||||
nplusx = nplx
|
||||
ifsx = 0
|
||||
do 220 l=1,nplusx
|
||||
c add a new knot in the x-direction
|
||||
call fpknot(x,mx,tx,nx,fpintx,nrdatx,nrintx,nxest,1)
|
||||
c test whether we cannot further increase the number of knots in the
|
||||
c x-direction.
|
||||
if(nx.eq.nxe) go to 250
|
||||
220 continue
|
||||
go to 250
|
||||
230 if(ny.eq.nye) go to 210
|
||||
c addition in the y-direction.
|
||||
lastdi = 1
|
||||
nplusy = nply
|
||||
ifsy = 0
|
||||
do 240 l=1,nplusy
|
||||
c add a new knot in the y-direction.
|
||||
call fpknot(y,my,ty,ny,fpinty,nrdaty,nrinty,nyest,1)
|
||||
c test whether we cannot further increase the number of knots in the
|
||||
c y-direction.
|
||||
if(ny.eq.nye) go to 250
|
||||
240 continue
|
||||
c restart the computations with the new set of knots.
|
||||
250 continue
|
||||
c test whether the least-squares polynomial is a solution of our
|
||||
c approximation problem.
|
||||
300 if(ier.eq.(-2)) go to 440
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 2: determination of the smoothing spline sp(x,y) c
|
||||
c ***************************************************** c
|
||||
c we have determined the number of knots and their position. we now c
|
||||
c compute the b-spline coefficients of the smoothing spline sp(x,y). c
|
||||
c this smoothing spline varies with the parameter p in such a way thatc
|
||||
c f(p) = sumi=1,mx(sumj=1,my((z(i,j)-sp(x(i),y(j)))**2) c
|
||||
c is a continuous, strictly decreasing function of p. moreover the c
|
||||
c least-squares polynomial corresponds to p=0 and the least-squares c
|
||||
c spline to p=infinity. iteratively we then have to determine the c
|
||||
c positive value of p such that f(p)=s. the process which is proposed c
|
||||
c here makes use of rational interpolation. f(p) is approximated by a c
|
||||
c rational function r(p)=(u*p+v)/(p+w); three values of p (p1,p2,p3) c
|
||||
c with corresponding values of f(p) (f1=f(p1)-s,f2=f(p2)-s,f3=f(p3)-s)c
|
||||
c are used to calculate the new value of p such that r(p)=s. c
|
||||
c convergence is guaranteed by taking f1 > 0 and f3 < 0. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c initial value for p.
|
||||
p1 = 0.
|
||||
f1 = fp0-s
|
||||
p3 = -one
|
||||
f3 = fpms
|
||||
p = one
|
||||
ich1 = 0
|
||||
ich3 = 0
|
||||
c iteration process to find the root of f(p)=s.
|
||||
do 350 iter = 1,maxit
|
||||
c find the smoothing spline sp(x,y) and the corresponding sum of
|
||||
c squared residuals fp.
|
||||
call fpgrre(ifsx,ifsy,ifbx,ifby,x,mx,y,my,z,mz,kx,ky,tx,nx,ty,
|
||||
* ny,p,c,nc,fp,fpintx,fpinty,mm,mynx,kx1,kx2,ky1,ky2,wrk(lsx),
|
||||
* wrk(lsy),wrk(lri),wrk(lq),wrk(lax),wrk(lay),wrk(lbx),wrk(lby),
|
||||
* nrx,nry)
|
||||
c test whether the approximation sp(x,y) is an acceptable solution.
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 440
|
||||
c test whether the maximum allowable number of iterations has been
|
||||
c reached.
|
||||
if(iter.eq.maxit) go to 400
|
||||
c carry out one more step of the iteration process.
|
||||
p2 = p
|
||||
f2 = fpms
|
||||
if(ich3.ne.0) go to 320
|
||||
if((f2-f3).gt.acc) go to 310
|
||||
c our initial choice of p is too large.
|
||||
p3 = p2
|
||||
f3 = f2
|
||||
p = p*con4
|
||||
if(p.le.p1) p = p1*con9 + p2*con1
|
||||
go to 350
|
||||
310 if(f2.lt.0.) ich3 = 1
|
||||
320 if(ich1.ne.0) go to 340
|
||||
if((f1-f2).gt.acc) go to 330
|
||||
c our initial choice of p is too small
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
p = p/con4
|
||||
if(p3.lt.0.) go to 350
|
||||
if(p.ge.p3) p = p2*con1 + p3*con9
|
||||
go to 350
|
||||
c test whether the iteration process proceeds as theoretically
|
||||
c expected.
|
||||
330 if(f2.gt.0.) ich1 = 1
|
||||
340 if(f2.ge.f1 .or. f2.le.f3) go to 410
|
||||
c find the new value of p.
|
||||
p = fprati(p1,f1,p2,f2,p3,f3)
|
||||
350 continue
|
||||
c error codes and messages.
|
||||
400 ier = 3
|
||||
go to 440
|
||||
410 ier = 2
|
||||
go to 440
|
||||
420 ier = 1
|
||||
go to 440
|
||||
430 ier = -1
|
||||
fp = 0.
|
||||
440 return
|
||||
end
|
||||
|
||||
14
cxx/fitpack/fprota.f
Normal file
14
cxx/fitpack/fprota.f
Normal file
@ -0,0 +1,14 @@
|
||||
recursive subroutine fprota(cos,sin,a,b)
|
||||
c subroutine fprota applies a givens rotation to a and b.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 cos,sin,a,b
|
||||
c ..local scalars..
|
||||
real*8 stor1,stor2
|
||||
c ..
|
||||
stor1 = a
|
||||
stor2 = b
|
||||
b = cos*stor2+sin*stor1
|
||||
a = cos*stor1-sin*stor2
|
||||
return
|
||||
end
|
||||
62
cxx/fitpack/fprppo.f
Normal file
62
cxx/fitpack/fprppo.f
Normal file
@ -0,0 +1,62 @@
|
||||
recursive subroutine fprppo(nu,nv,if1,if2,cosi,ratio,c,f,ncoff)
|
||||
implicit none
|
||||
c given the coefficients of a constrained bicubic spline, as determined
|
||||
c in subroutine fppola, subroutine fprppo calculates the coefficients
|
||||
c in the standard b-spline representation of bicubic splines.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 ratio
|
||||
integer nu,nv,if1,if2,ncoff
|
||||
c ..array arguments
|
||||
real*8 c(ncoff),f(ncoff),cosi(5,nv)
|
||||
c ..local scalars..
|
||||
integer i,iopt,ii,j,k,l,nu4,nvv
|
||||
c ..
|
||||
nu4 = nu-4
|
||||
nvv = nv-7
|
||||
iopt = if1+1
|
||||
do 10 i=1,ncoff
|
||||
f(i) = 0.
|
||||
10 continue
|
||||
i = 0
|
||||
do 120 l=1,nu4
|
||||
ii = i
|
||||
if(l.gt.iopt) go to 80
|
||||
go to (20,40,60),l
|
||||
20 do 30 k=1,nvv
|
||||
i = i+1
|
||||
f(i) = c(1)
|
||||
30 continue
|
||||
j = 1
|
||||
go to 100
|
||||
40 do 50 k=1,nvv
|
||||
i = i+1
|
||||
f(i) = c(1)+c(2)*cosi(1,k)+c(3)*cosi(2,k)
|
||||
50 continue
|
||||
j = 3
|
||||
go to 100
|
||||
60 do 70 k=1,nvv
|
||||
i = i+1
|
||||
f(i) = c(1)+ratio*(c(2)*cosi(1,k)+c(3)*cosi(2,k))+
|
||||
* c(4)*cosi(3,k)+c(5)*cosi(4,k)+c(6)*cosi(5,k)
|
||||
70 continue
|
||||
j = 6
|
||||
go to 100
|
||||
80 if(l.eq.nu4 .and. if2.ne.0) go to 120
|
||||
do 90 k=1,nvv
|
||||
i = i+1
|
||||
j = j+1
|
||||
f(i) = c(j)
|
||||
90 continue
|
||||
100 do 110 k=1,3
|
||||
ii = ii+1
|
||||
i = i+1
|
||||
f(i) = f(ii)
|
||||
110 continue
|
||||
120 continue
|
||||
do 130 i=1,ncoff
|
||||
c(i) = f(i)
|
||||
130 continue
|
||||
return
|
||||
end
|
||||
|
||||
56
cxx/fitpack/fprpsp.f
Normal file
56
cxx/fitpack/fprpsp.f
Normal file
@ -0,0 +1,56 @@
|
||||
recursive subroutine fprpsp(nt,np,co,si,c,f,ncoff)
|
||||
implicit none
|
||||
c given the coefficients of a spherical spline function, subroutine
|
||||
c fprpsp calculates the coefficients in the standard b-spline re-
|
||||
c presentation of this bicubic spline.
|
||||
c ..
|
||||
c ..scalar arguments
|
||||
integer nt,np,ncoff
|
||||
c ..array arguments
|
||||
real*8 co(np),si(np),c(ncoff),f(ncoff)
|
||||
c ..local scalars
|
||||
real*8 cn,c1,c2,c3
|
||||
integer i,ii,j,k,l,ncof,npp,np4,nt4
|
||||
c ..
|
||||
nt4 = nt-4
|
||||
np4 = np-4
|
||||
npp = np4-3
|
||||
ncof = 6+npp*(nt4-4)
|
||||
c1 = c(1)
|
||||
cn = c(ncof)
|
||||
j = ncoff
|
||||
do 10 i=1,np4
|
||||
f(i) = c1
|
||||
f(j) = cn
|
||||
j = j-1
|
||||
10 continue
|
||||
i = np4
|
||||
j=1
|
||||
do 70 l=3,nt4
|
||||
ii = i
|
||||
if(l.eq.3 .or. l.eq.nt4) go to 30
|
||||
do 20 k=1,npp
|
||||
i = i+1
|
||||
j = j+1
|
||||
f(i) = c(j)
|
||||
20 continue
|
||||
go to 50
|
||||
30 if(l.eq.nt4) c1 = cn
|
||||
c2 = c(j+1)
|
||||
c3 = c(j+2)
|
||||
j = j+2
|
||||
do 40 k=1,npp
|
||||
i = i+1
|
||||
f(i) = c1+c2*co(k)+c3*si(k)
|
||||
40 continue
|
||||
50 do 60 k=1,3
|
||||
ii = ii+1
|
||||
i = i+1
|
||||
f(i) = f(ii)
|
||||
60 continue
|
||||
70 continue
|
||||
do 80 i=1,ncoff
|
||||
c(i) = f(i)
|
||||
80 continue
|
||||
return
|
||||
end
|
||||
36
cxx/fitpack/fpseno.f
Normal file
36
cxx/fitpack/fpseno.f
Normal file
@ -0,0 +1,36 @@
|
||||
recursive subroutine fpseno(maxtr,up,left,right,info,merk,
|
||||
* ibind,nbind)
|
||||
implicit none
|
||||
c subroutine fpseno fetches a branch of a triply linked tree the
|
||||
c information of which is kept in the arrays up,left,right and info.
|
||||
c the branch has a specified length nbind and is determined by the
|
||||
c parameter merk which points to its terminal node. the information
|
||||
c field of the nodes of this branch is stored in the array ibind. on
|
||||
c exit merk points to a new branch of length nbind or takes the value
|
||||
c 1 if no such branch was found.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer maxtr,merk,nbind
|
||||
c ..array arguments..
|
||||
integer up(maxtr),left(maxtr),right(maxtr),info(maxtr),
|
||||
* ibind(nbind)
|
||||
c ..scalar arguments..
|
||||
integer i,j,k
|
||||
c ..
|
||||
k = merk
|
||||
j = nbind
|
||||
do 10 i=1,nbind
|
||||
ibind(j) = info(k)
|
||||
k = up(k)
|
||||
j = j-1
|
||||
10 continue
|
||||
20 k = right(merk)
|
||||
if(k.ne.0) go to 30
|
||||
merk = up(merk)
|
||||
if (merk.le.1) go to 40
|
||||
go to 20
|
||||
30 merk = k
|
||||
k = left(merk)
|
||||
if(k.ne.0) go to 30
|
||||
40 return
|
||||
end
|
||||
440
cxx/fitpack/fpspgr.f
Normal file
440
cxx/fitpack/fpspgr.f
Normal file
@ -0,0 +1,440 @@
|
||||
recursive subroutine fpspgr(iopt,ider,u,mu,v,mv,r,mr,r0,r1,s,
|
||||
* nuest,nvest,tol,maxit,nc,nu,tu,nv,tv,c,fp,fp0,fpold,reducu,
|
||||
* reducv,fpintu,fpintv,dr,step,lastdi,nplusu,nplusv,lastu0,
|
||||
* lastu1,nru,nrv,nrdatu,nrdatv,wrk,lwrk,ier)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer mu,mv,mr,nuest,nvest,maxit,nc,nu,nv,lastdi,nplusu,nplusv,
|
||||
* lastu0,lastu1,lwrk,ier
|
||||
real*8 r0,r1,s,tol,fp,fp0,fpold,reducu,reducv
|
||||
c ..array arguments..
|
||||
integer iopt(3),ider(4),nrdatu(nuest),nrdatv(nvest),nru(mu),
|
||||
* nrv(mv)
|
||||
real*8 u(mu),v(mv),r(mr),tu(nuest),tv(nvest),c(nc),fpintu(nuest),
|
||||
* fpintv(nvest),dr(6),wrk(lwrk),step(2)
|
||||
c ..local scalars..
|
||||
real*8 acc,fpms,f1,f2,f3,p,per,pi,p1,p2,p3,vb,ve,rmax,rmin,rn,one,
|
||||
*
|
||||
* con1,con4,con9
|
||||
integer i,ich1,ich3,ifbu,ifbv,ifsu,ifsv,istart,iter,i1,i2,j,ju,
|
||||
* ktu,l,l1,l2,l3,l4,mpm,mumin,mu0,mu1,nn,nplu,nplv,npl1,nrintu,
|
||||
* nrintv,nue,numax,nve,nvmax
|
||||
c ..local arrays..
|
||||
integer idd(4)
|
||||
real*8 drr(6)
|
||||
c ..function references..
|
||||
real*8 abs,datan2,fprati
|
||||
integer max0,min0
|
||||
c ..subroutine references..
|
||||
c fpknot,fpopsp
|
||||
c ..
|
||||
c set constants
|
||||
one = 1d0
|
||||
con1 = 0.1e0
|
||||
con9 = 0.9e0
|
||||
con4 = 0.4e-01
|
||||
c initialization
|
||||
ifsu = 0
|
||||
ifsv = 0
|
||||
ifbu = 0
|
||||
ifbv = 0
|
||||
p = -one
|
||||
mumin = 4
|
||||
if(ider(1).ge.0) mumin = mumin-1
|
||||
if(iopt(2).eq.1 .and. ider(2).eq.1) mumin = mumin-1
|
||||
if(ider(3).ge.0) mumin = mumin-1
|
||||
if(iopt(3).eq.1 .and. ider(4).eq.1) mumin = mumin-1
|
||||
if(mumin.eq.0) mumin = 1
|
||||
pi = datan2(0d0,-one)
|
||||
per = pi+pi
|
||||
vb = v(1)
|
||||
ve = vb+per
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 1: determination of the number of knots and their position. c
|
||||
c **************************************************************** c
|
||||
c given a set of knots we compute the least-squares spline sinf(u,v) c
|
||||
c and the corresponding sum of squared residuals fp = f(p=inf). c
|
||||
c if iopt(1)=-1 sinf(u,v) is the requested approximation. c
|
||||
c if iopt(1)>=0 we check whether we can accept the knots: c
|
||||
c if fp <= s we will continue with the current set of knots. c
|
||||
c if fp > s we will increase the number of knots and compute the c
|
||||
c corresponding least-squares spline until finally fp <= s. c
|
||||
c the initial choice of knots depends on the value of s and iopt. c
|
||||
c if s=0 we have spline interpolation; in that case the number of c
|
||||
c knots in the u-direction equals nu=numax=mu+6+iopt(2)+iopt(3) c
|
||||
c and in the v-direction nv=nvmax=mv+7. c
|
||||
c if s>0 and c
|
||||
c iopt(1)=0 we first compute the least-squares polynomial,i.e. a c
|
||||
c spline without interior knots : nu=8 ; nv=8. c
|
||||
c iopt(1)=1 we start with the set of knots found at the last call c
|
||||
c of the routine, except for the case that s > fp0; then we c
|
||||
c compute the least-squares polynomial directly. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
if(iopt(1).lt.0) go to 120
|
||||
c acc denotes the absolute tolerance for the root of f(p)=s.
|
||||
acc = tol*s
|
||||
c numax and nvmax denote the number of knots needed for interpolation.
|
||||
numax = mu+6+iopt(2)+iopt(3)
|
||||
nvmax = mv+7
|
||||
nue = min0(numax,nuest)
|
||||
nve = min0(nvmax,nvest)
|
||||
if(s.gt.0.) go to 100
|
||||
c if s = 0, s(u,v) is an interpolating spline.
|
||||
nu = numax
|
||||
nv = nvmax
|
||||
c test whether the required storage space exceeds the available one.
|
||||
if(nu.gt.nuest .or. nv.gt.nvest) go to 420
|
||||
c find the position of the knots in the v-direction.
|
||||
do 10 l=1,mv
|
||||
tv(l+3) = v(l)
|
||||
10 continue
|
||||
tv(mv+4) = ve
|
||||
l1 = mv-2
|
||||
l2 = mv+5
|
||||
do 20 i=1,3
|
||||
tv(i) = v(l1)-per
|
||||
tv(l2) = v(i+1)+per
|
||||
l1 = l1+1
|
||||
l2 = l2+1
|
||||
20 continue
|
||||
c if not all the derivative values g(i,j) are given, we will first
|
||||
c estimate these values by computing a least-squares spline
|
||||
idd(1) = ider(1)
|
||||
if(idd(1).eq.0) idd(1) = 1
|
||||
if(idd(1).gt.0) dr(1) = r0
|
||||
idd(2) = ider(2)
|
||||
idd(3) = ider(3)
|
||||
if(idd(3).eq.0) idd(3) = 1
|
||||
if(idd(3).gt.0) dr(4) = r1
|
||||
idd(4) = ider(4)
|
||||
if(ider(1).lt.0 .or. ider(3).lt.0) go to 30
|
||||
if(iopt(2).ne.0 .and. ider(2).eq.0) go to 30
|
||||
if(iopt(3).eq.0 .or. ider(4).ne.0) go to 70
|
||||
c we set up the knots in the u-direction for computing the least-squares
|
||||
c spline.
|
||||
30 i1 = 3
|
||||
i2 = mu-2
|
||||
nu = 4
|
||||
do 40 i=1,mu
|
||||
if(i1.gt.i2) go to 50
|
||||
nu = nu+1
|
||||
tu(nu) = u(i1)
|
||||
i1 = i1+2
|
||||
40 continue
|
||||
50 do 60 i=1,4
|
||||
tu(i) = 0.
|
||||
nu = nu+1
|
||||
tu(nu) = pi
|
||||
60 continue
|
||||
c we compute the least-squares spline for estimating the derivatives.
|
||||
call fpopsp(ifsu,ifsv,ifbu,ifbv,u,mu,v,mv,r,mr,r0,r1,dr,iopt,idd,
|
||||
* tu,nu,tv,nv,nuest,nvest,p,step,c,nc,fp,fpintu,fpintv,nru,nrv,
|
||||
* wrk,lwrk)
|
||||
ifsu = 0
|
||||
c if all the derivatives at the origin are known, we compute the
|
||||
c interpolating spline.
|
||||
c we set up the knots in the u-direction, needed for interpolation.
|
||||
70 nn = numax-8
|
||||
if(nn.eq.0) go to 95
|
||||
ju = 2-iopt(2)
|
||||
do 80 l=1,nn
|
||||
tu(l+4) = u(ju)
|
||||
ju = ju+1
|
||||
80 continue
|
||||
nu = numax
|
||||
l = nu
|
||||
do 90 i=1,4
|
||||
tu(i) = 0.
|
||||
tu(l) = pi
|
||||
l = l-1
|
||||
90 continue
|
||||
c we compute the interpolating spline.
|
||||
95 call fpopsp(ifsu,ifsv,ifbu,ifbv,u,mu,v,mv,r,mr,r0,r1,dr,iopt,idd,
|
||||
* tu,nu,tv,nv,nuest,nvest,p,step,c,nc,fp,fpintu,fpintv,nru,nrv,
|
||||
* wrk,lwrk)
|
||||
go to 430
|
||||
c if s>0 our initial choice of knots depends on the value of iopt(1).
|
||||
100 ier = 0
|
||||
if(iopt(1).eq.0) go to 115
|
||||
step(1) = -step(1)
|
||||
step(2) = -step(2)
|
||||
if(fp0.le.s) go to 115
|
||||
c if iopt(1)=1 and fp0 > s we start computing the least-squares spline
|
||||
c according to the set of knots found at the last call of the routine.
|
||||
c we determine the number of grid coordinates u(i) inside each knot
|
||||
c interval (tu(l),tu(l+1)).
|
||||
l = 5
|
||||
j = 1
|
||||
nrdatu(1) = 0
|
||||
mu0 = 2-iopt(2)
|
||||
mu1 = mu-1+iopt(3)
|
||||
do 105 i=mu0,mu1
|
||||
nrdatu(j) = nrdatu(j)+1
|
||||
if(u(i).lt.tu(l)) go to 105
|
||||
nrdatu(j) = nrdatu(j)-1
|
||||
l = l+1
|
||||
j = j+1
|
||||
nrdatu(j) = 0
|
||||
105 continue
|
||||
c we determine the number of grid coordinates v(i) inside each knot
|
||||
c interval (tv(l),tv(l+1)).
|
||||
l = 5
|
||||
j = 1
|
||||
nrdatv(1) = 0
|
||||
do 110 i=2,mv
|
||||
nrdatv(j) = nrdatv(j)+1
|
||||
if(v(i).lt.tv(l)) go to 110
|
||||
nrdatv(j) = nrdatv(j)-1
|
||||
l = l+1
|
||||
j = j+1
|
||||
nrdatv(j) = 0
|
||||
110 continue
|
||||
idd(1) = ider(1)
|
||||
idd(2) = ider(2)
|
||||
idd(3) = ider(3)
|
||||
idd(4) = ider(4)
|
||||
go to 120
|
||||
c if iopt(1)=0 or iopt(1)=1 and s >= fp0,we start computing the least-
|
||||
c squares polynomial (which is a spline without interior knots).
|
||||
115 ier = -2
|
||||
idd(1) = ider(1)
|
||||
idd(2) = 1
|
||||
idd(3) = ider(3)
|
||||
idd(4) = 1
|
||||
nu = 8
|
||||
nv = 8
|
||||
nrdatu(1) = mu-2+iopt(2)+iopt(3)
|
||||
nrdatv(1) = mv-1
|
||||
lastdi = 0
|
||||
nplusu = 0
|
||||
nplusv = 0
|
||||
fp0 = 0.
|
||||
fpold = 0.
|
||||
reducu = 0.
|
||||
reducv = 0.
|
||||
c main loop for the different sets of knots.mpm=mu+mv is a save upper
|
||||
c bound for the number of trials.
|
||||
120 mpm = mu+mv
|
||||
do 270 iter=1,mpm
|
||||
c find nrintu (nrintv) which is the number of knot intervals in the
|
||||
c u-direction (v-direction).
|
||||
nrintu = nu-7
|
||||
nrintv = nv-7
|
||||
c find the position of the additional knots which are needed for the
|
||||
c b-spline representation of s(u,v).
|
||||
i = nu
|
||||
do 125 j=1,4
|
||||
tu(j) = 0.
|
||||
tu(i) = pi
|
||||
i = i-1
|
||||
125 continue
|
||||
l1 = 4
|
||||
l2 = l1
|
||||
l3 = nv-3
|
||||
l4 = l3
|
||||
tv(l2) = vb
|
||||
tv(l3) = ve
|
||||
do 130 j=1,3
|
||||
l1 = l1+1
|
||||
l2 = l2-1
|
||||
l3 = l3+1
|
||||
l4 = l4-1
|
||||
tv(l2) = tv(l4)-per
|
||||
tv(l3) = tv(l1)+per
|
||||
130 continue
|
||||
c find an estimate of the range of possible values for the optimal
|
||||
c derivatives at the origin.
|
||||
ktu = nrdatu(1)+2-iopt(2)
|
||||
if(ktu.lt.mumin) ktu = mumin
|
||||
if(ktu.eq.lastu0) go to 140
|
||||
rmin = r0
|
||||
rmax = r0
|
||||
l = mv*ktu
|
||||
do 135 i=1,l
|
||||
if(r(i).lt.rmin) rmin = r(i)
|
||||
if(r(i).gt.rmax) rmax = r(i)
|
||||
135 continue
|
||||
step(1) = rmax-rmin
|
||||
lastu0 = ktu
|
||||
140 ktu = nrdatu(nrintu)+2-iopt(3)
|
||||
if(ktu.lt.mumin) ktu = mumin
|
||||
if(ktu.eq.lastu1) go to 150
|
||||
rmin = r1
|
||||
rmax = r1
|
||||
l = mv*ktu
|
||||
j = mr
|
||||
do 145 i=1,l
|
||||
if(r(j).lt.rmin) rmin = r(j)
|
||||
if(r(j).gt.rmax) rmax = r(j)
|
||||
j = j-1
|
||||
145 continue
|
||||
step(2) = rmax-rmin
|
||||
lastu1 = ktu
|
||||
c find the least-squares spline sinf(u,v).
|
||||
150 call fpopsp(ifsu,ifsv,ifbu,ifbv,u,mu,v,mv,r,mr,r0,r1,dr,iopt,
|
||||
* idd,tu,nu,tv,nv,nuest,nvest,p,step,c,nc,fp,fpintu,fpintv,nru,
|
||||
* nrv,wrk,lwrk)
|
||||
if(step(1).lt.0.) step(1) = -step(1)
|
||||
if(step(2).lt.0.) step(2) = -step(2)
|
||||
if(ier.eq.(-2)) fp0 = fp
|
||||
c test whether the least-squares spline is an acceptable solution.
|
||||
if(iopt(1).lt.0) go to 440
|
||||
fpms = fp-s
|
||||
if(abs(fpms) .lt. acc) go to 440
|
||||
c if f(p=inf) < s, we accept the choice of knots.
|
||||
if(fpms.lt.0.) go to 300
|
||||
c if nu=numax and nv=nvmax, sinf(u,v) is an interpolating spline
|
||||
if(nu.eq.numax .and. nv.eq.nvmax) go to 430
|
||||
c increase the number of knots.
|
||||
c if nu=nue and nv=nve we cannot further increase the number of knots
|
||||
c because of the storage capacity limitation.
|
||||
if(nu.eq.nue .and. nv.eq.nve) go to 420
|
||||
if(ider(1).eq.0) fpintu(1) = fpintu(1)+(r0-dr(1))**2
|
||||
if(ider(3).eq.0) fpintu(nrintu) = fpintu(nrintu)+(r1-dr(4))**2
|
||||
ier = 0
|
||||
c adjust the parameter reducu or reducv according to the direction
|
||||
c in which the last added knots were located.
|
||||
if (lastdi.lt.0) go to 160
|
||||
if (lastdi.eq.0) go to 155
|
||||
go to 170
|
||||
155 nplv = 3
|
||||
idd(2) = ider(2)
|
||||
idd(4) = ider(4)
|
||||
fpold = fp
|
||||
go to 230
|
||||
160 reducu = fpold-fp
|
||||
go to 175
|
||||
170 reducv = fpold-fp
|
||||
c store the sum of squared residuals for the current set of knots.
|
||||
175 fpold = fp
|
||||
c find nplu, the number of knots we should add in the u-direction.
|
||||
nplu = 1
|
||||
if(nu.eq.8) go to 180
|
||||
npl1 = nplusu*2
|
||||
rn = nplusu
|
||||
if(reducu.gt.acc) npl1 = rn*fpms/reducu
|
||||
nplu = min0(nplusu*2,max0(npl1,nplusu/2,1))
|
||||
c find nplv, the number of knots we should add in the v-direction.
|
||||
180 nplv = 3
|
||||
if(nv.eq.8) go to 190
|
||||
npl1 = nplusv*2
|
||||
rn = nplusv
|
||||
if(reducv.gt.acc) npl1 = rn*fpms/reducv
|
||||
nplv = min0(nplusv*2,max0(npl1,nplusv/2,1))
|
||||
c test whether we are going to add knots in the u- or v-direction.
|
||||
190 if (nplu.lt.nplv) go to 210
|
||||
if (nplu.eq.nplv) go to 200
|
||||
go to 230
|
||||
200 if(lastdi.lt.0) go to 230
|
||||
210 if(nu.eq.nue) go to 230
|
||||
c addition in the u-direction.
|
||||
lastdi = -1
|
||||
nplusu = nplu
|
||||
ifsu = 0
|
||||
istart = 0
|
||||
if(iopt(2).eq.0) istart = 1
|
||||
do 220 l=1,nplusu
|
||||
c add a new knot in the u-direction
|
||||
call fpknot(u,mu,tu,nu,fpintu,nrdatu,nrintu,nuest,istart)
|
||||
c test whether we cannot further increase the number of knots in the
|
||||
c u-direction.
|
||||
if(nu.eq.nue) go to 270
|
||||
220 continue
|
||||
go to 270
|
||||
230 if(nv.eq.nve) go to 210
|
||||
c addition in the v-direction.
|
||||
lastdi = 1
|
||||
nplusv = nplv
|
||||
ifsv = 0
|
||||
do 240 l=1,nplusv
|
||||
c add a new knot in the v-direction.
|
||||
call fpknot(v,mv,tv,nv,fpintv,nrdatv,nrintv,nvest,1)
|
||||
c test whether we cannot further increase the number of knots in the
|
||||
c v-direction.
|
||||
if(nv.eq.nve) go to 270
|
||||
240 continue
|
||||
c restart the computations with the new set of knots.
|
||||
270 continue
|
||||
c test whether the least-squares polynomial is a solution of our
|
||||
c approximation problem.
|
||||
300 if(ier.eq.(-2)) go to 440
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 2: determination of the smoothing spline sp(u,v) c
|
||||
c ***************************************************** c
|
||||
c we have determined the number of knots and their position. we now c
|
||||
c compute the b-spline coefficients of the smoothing spline sp(u,v). c
|
||||
c this smoothing spline depends on the parameter p in such a way that c
|
||||
c f(p) = sumi=1,mu(sumj=1,mv((z(i,j)-sp(u(i),v(j)))**2) c
|
||||
c is a continuous, strictly decreasing function of p. moreover the c
|
||||
c least-squares polynomial corresponds to p=0 and the least-squares c
|
||||
c spline to p=infinity. then iteratively we have to determine the c
|
||||
c positive value of p such that f(p)=s. the process which is proposed c
|
||||
c here makes use of rational interpolation. f(p) is approximated by a c
|
||||
c rational function r(p)=(u*p+v)/(p+w); three values of p (p1,p2,p3) c
|
||||
c with corresponding values of f(p) (f1=f(p1)-s,f2=f(p2)-s,f3=f(p3)-s)c
|
||||
c are used to calculate the new value of p such that r(p)=s. c
|
||||
c convergence is guaranteed by taking f1 > 0 and f3 < 0. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c initial value for p.
|
||||
p1 = 0.
|
||||
f1 = fp0-s
|
||||
p3 = -one
|
||||
f3 = fpms
|
||||
p = one
|
||||
do 305 i=1,6
|
||||
drr(i) = dr(i)
|
||||
305 continue
|
||||
ich1 = 0
|
||||
ich3 = 0
|
||||
c iteration process to find the root of f(p)=s.
|
||||
do 350 iter = 1,maxit
|
||||
c find the smoothing spline sp(u,v) and the corresponding sum f(p).
|
||||
call fpopsp(ifsu,ifsv,ifbu,ifbv,u,mu,v,mv,r,mr,r0,r1,drr,iopt,
|
||||
* idd,tu,nu,tv,nv,nuest,nvest,p,step,c,nc,fp,fpintu,fpintv,nru,
|
||||
* nrv,wrk,lwrk)
|
||||
c test whether the approximation sp(u,v) is an acceptable solution.
|
||||
fpms = fp-s
|
||||
if(abs(fpms).lt.acc) go to 440
|
||||
c test whether the maximum allowable number of iterations has been
|
||||
c reached.
|
||||
if(iter.eq.maxit) go to 400
|
||||
c carry out one more step of the iteration process.
|
||||
p2 = p
|
||||
f2 = fpms
|
||||
if(ich3.ne.0) go to 320
|
||||
if((f2-f3).gt.acc) go to 310
|
||||
c our initial choice of p is too large.
|
||||
p3 = p2
|
||||
f3 = f2
|
||||
p = p*con4
|
||||
if(p.le.p1) p = p1*con9 + p2*con1
|
||||
go to 350
|
||||
310 if(f2.lt.0.) ich3 = 1
|
||||
320 if(ich1.ne.0) go to 340
|
||||
if((f1-f2).gt.acc) go to 330
|
||||
c our initial choice of p is too small
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
p = p/con4
|
||||
if(p3.lt.0.) go to 350
|
||||
if(p.ge.p3) p = p2*con1 + p3*con9
|
||||
go to 350
|
||||
c test whether the iteration process proceeds as theoretically
|
||||
c expected.
|
||||
330 if(f2.gt.0.) ich1 = 1
|
||||
340 if(f2.ge.f1 .or. f2.le.f3) go to 410
|
||||
c find the new value of p.
|
||||
p = fprati(p1,f1,p2,f2,p3,f3)
|
||||
350 continue
|
||||
c error codes and messages.
|
||||
400 ier = 3
|
||||
go to 440
|
||||
410 ier = 2
|
||||
go to 440
|
||||
420 ier = 1
|
||||
go to 440
|
||||
430 ier = -1
|
||||
fp = 0.
|
||||
440 return
|
||||
end
|
||||
765
cxx/fitpack/fpsphe.f
Normal file
765
cxx/fitpack/fpsphe.f
Normal file
@ -0,0 +1,765 @@
|
||||
recursive subroutine fpsphe(iopt,m,teta,phi,r,w,s,ntest,npest,
|
||||
* eta,tol,maxit,
|
||||
* ib1,ib3,nc,ncc,intest,nrest,nt,tt,np,tp,c,fp,sup,fpint,coord,f,
|
||||
* ff,row,coco,cosi,a,q,bt,bp,spt,spp,h,index,nummer,wrk,lwrk,ier)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer iopt,m,ntest,npest,maxit,ib1,ib3,nc,ncc,intest,nrest,
|
||||
* nt,np,lwrk,ier
|
||||
real*8 s,eta,tol,fp,sup
|
||||
c ..array arguments..
|
||||
real*8 teta(m),phi(m),r(m),w(m),tt(ntest),tp(npest),c(nc),
|
||||
* fpint(intest),coord(intest),f(ncc),ff(nc),row(npest),coco(npest),
|
||||
*
|
||||
* cosi(npest),a(ncc,ib1),q(ncc,ib3),bt(ntest,5),bp(npest,5),
|
||||
* spt(m,4),spp(m,4),h(ib3),wrk(lwrk)
|
||||
integer index(nrest),nummer(m)
|
||||
c ..local scalars..
|
||||
real*8 aa,acc,arg,cn,co,c1,dmax,d1,d2,eps,facc,facs,fac1,fac2,fn,
|
||||
* fpmax,fpms,f1,f2,f3,hti,htj,p,pi,pinv,piv,pi2,p1,p2,p3,ri,si,
|
||||
* sigma,sq,store,wi,rn,one,con1,con9,con4,half,ten
|
||||
integer i,iband,iband1,iband3,iband4,ich1,ich3,ii,ij,il,in,irot,
|
||||
* iter,i1,i2,i3,j,jlt,jrot,j1,j2,l,la,lf,lh,ll,lp,lt,lwest,l1,l2,
|
||||
* l3,l4,ncof,ncoff,npp,np4,nreg,nrint,nrr,nr1,ntt,nt4,nt6,num,
|
||||
* num1,rank
|
||||
c ..local arrays..
|
||||
real*8 ht(4),hp(4)
|
||||
c ..function references..
|
||||
real*8 abs,atan,fprati,sqrt,cos,sin
|
||||
integer min0
|
||||
c ..subroutine references..
|
||||
c fpback,fpbspl,fpgivs,fpdisc,fporde,fprank,fprota,fprpsp
|
||||
c ..
|
||||
c set constants
|
||||
one = 0.1e+01
|
||||
con1 = 0.1e0
|
||||
con9 = 0.9e0
|
||||
con4 = 0.4e-01
|
||||
half = 0.5e0
|
||||
ten = 0.1e+02
|
||||
pi = atan(one)*4
|
||||
pi2 = pi+pi
|
||||
eps = sqrt(eta)
|
||||
if(iopt.lt.0) go to 70
|
||||
c calculation of acc, the absolute tolerance for the root of f(p)=s.
|
||||
acc = tol*s
|
||||
if(iopt.eq.0) go to 10
|
||||
if(s.lt.sup) then
|
||||
if (np.lt.11) go to 60
|
||||
go to 70
|
||||
endif
|
||||
c if iopt=0 we begin by computing the weighted least-squares polynomial
|
||||
c of the form
|
||||
c s(teta,phi) = c1*f1(teta) + cn*fn(teta)
|
||||
c where f1(teta) and fn(teta) are the cubic polynomials satisfying
|
||||
c f1(0) = 1, f1(pi) = f1'(0) = f1'(pi) = 0 ; fn(teta) = 1-f1(teta).
|
||||
c the corresponding weighted sum of squared residuals gives the upper
|
||||
c bound sup for the smoothing factor s.
|
||||
10 sup = 0.
|
||||
d1 = 0.
|
||||
d2 = 0.
|
||||
c1 = 0.
|
||||
cn = 0.
|
||||
fac1 = pi*(one + half)
|
||||
fac2 = (one + one)/pi**3
|
||||
aa = 0.
|
||||
do 40 i=1,m
|
||||
wi = w(i)
|
||||
ri = r(i)*wi
|
||||
arg = teta(i)
|
||||
fn = fac2*arg*arg*(fac1-arg)
|
||||
f1 = (one-fn)*wi
|
||||
fn = fn*wi
|
||||
if(fn.eq.0.) go to 20
|
||||
call fpgivs(fn,d1,co,si)
|
||||
call fprota(co,si,f1,aa)
|
||||
call fprota(co,si,ri,cn)
|
||||
20 if(f1.eq.0.) go to 30
|
||||
call fpgivs(f1,d2,co,si)
|
||||
call fprota(co,si,ri,c1)
|
||||
30 sup = sup+ri*ri
|
||||
40 continue
|
||||
if(d2.ne.0.) c1 = c1/d2
|
||||
if(d1.ne.0.) cn = (cn-aa*c1)/d1
|
||||
c find the b-spline representation of this least-squares polynomial
|
||||
nt = 8
|
||||
np = 8
|
||||
do 50 i=1,4
|
||||
c(i) = c1
|
||||
c(i+4) = c1
|
||||
c(i+8) = cn
|
||||
c(i+12) = cn
|
||||
tt(i) = 0.
|
||||
tt(i+4) = pi
|
||||
tp(i) = 0.
|
||||
tp(i+4) = pi2
|
||||
50 continue
|
||||
fp = sup
|
||||
c test whether the least-squares polynomial is an acceptable solution
|
||||
fpms = sup-s
|
||||
if(fpms.lt.acc) go to 960
|
||||
c test whether we cannot further increase the number of knots.
|
||||
60 if(npest.lt.11 .or. ntest.lt.9) go to 950
|
||||
c find the initial set of interior knots of the spherical spline in
|
||||
c case iopt = 0.
|
||||
np = 11
|
||||
tp(5) = pi*half
|
||||
tp(6) = pi
|
||||
tp(7) = tp(5)+pi
|
||||
nt = 9
|
||||
tt(5) = tp(5)
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 1 : computation of least-squares spherical splines. c
|
||||
c ******************************************************** c
|
||||
c if iopt < 0 we compute the least-squares spherical spline according c
|
||||
c to the given set of knots. c
|
||||
c if iopt >=0 we compute least-squares spherical splines with increas-c
|
||||
c ing numbers of knots until the corresponding sum f(p=inf)<=s. c
|
||||
c the initial set of knots then depends on the value of iopt: c
|
||||
c if iopt=0 we start with one interior knot in the teta-direction c
|
||||
c (pi/2) and three in the phi-direction (pi/2,pi,3*pi/2). c
|
||||
c if iopt>0 we start with the set of knots found at the last call c
|
||||
c of the routine. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c main loop for the different sets of knots. m is a save upper bound
|
||||
c for the number of trials.
|
||||
70 do 570 iter=1,m
|
||||
c find the position of the additional knots which are needed for the
|
||||
c b-spline representation of s(teta,phi).
|
||||
l1 = 4
|
||||
l2 = l1
|
||||
l3 = np-3
|
||||
l4 = l3
|
||||
tp(l2) = 0.
|
||||
tp(l3) = pi2
|
||||
do 80 i=1,3
|
||||
l1 = l1+1
|
||||
l2 = l2-1
|
||||
l3 = l3+1
|
||||
l4 = l4-1
|
||||
tp(l2) = tp(l4)-pi2
|
||||
tp(l3) = tp(l1)+pi2
|
||||
80 continue
|
||||
l = nt
|
||||
do 90 i=1,4
|
||||
tt(i) = 0.
|
||||
tt(l) = pi
|
||||
l = l-1
|
||||
90 continue
|
||||
c find nrint, the total number of knot intervals and nreg, the number
|
||||
c of panels in which the approximation domain is subdivided by the
|
||||
c intersection of knots.
|
||||
ntt = nt-7
|
||||
npp = np-7
|
||||
nrr = npp/2
|
||||
nr1 = nrr+1
|
||||
nrint = ntt+npp
|
||||
nreg = ntt*npp
|
||||
c arrange the data points according to the panel they belong to.
|
||||
call fporde(teta,phi,m,3,3,tt,nt,tp,np,nummer,index,nreg)
|
||||
c find the b-spline coefficients coco and cosi of the cubic spline
|
||||
c approximations sc(phi) and ss(phi) for cos(phi) and sin(phi).
|
||||
do 100 i=1,npp
|
||||
coco(i) = 0.
|
||||
cosi(i) = 0.
|
||||
do 100 j=1,npp
|
||||
a(i,j) = 0.
|
||||
100 continue
|
||||
c the coefficients coco and cosi are obtained from the conditions
|
||||
c sc(tp(i))=cos(tp(i)),resp. ss(tp(i))=sin(tp(i)),i=4,5,...np-4.
|
||||
do 150 i=1,npp
|
||||
l2 = i+3
|
||||
arg = tp(l2)
|
||||
call fpbspl(tp,np,3,arg,l2,hp)
|
||||
do 110 j=1,npp
|
||||
row(j) = 0.
|
||||
110 continue
|
||||
ll = i
|
||||
do 120 j=1,3
|
||||
if(ll.gt.npp) ll= 1
|
||||
row(ll) = row(ll)+hp(j)
|
||||
ll = ll+1
|
||||
120 continue
|
||||
facc = cos(arg)
|
||||
facs = sin(arg)
|
||||
do 140 j=1,npp
|
||||
piv = row(j)
|
||||
if(piv.eq.0.) go to 140
|
||||
call fpgivs(piv,a(j,1),co,si)
|
||||
call fprota(co,si,facc,coco(j))
|
||||
call fprota(co,si,facs,cosi(j))
|
||||
if(j.eq.npp) go to 150
|
||||
j1 = j+1
|
||||
i2 = 1
|
||||
do 130 l=j1,npp
|
||||
i2 = i2+1
|
||||
call fprota(co,si,row(l),a(j,i2))
|
||||
130 continue
|
||||
140 continue
|
||||
150 continue
|
||||
call fpback(a,coco,npp,npp,coco,ncc)
|
||||
call fpback(a,cosi,npp,npp,cosi,ncc)
|
||||
c find ncof, the dimension of the spherical spline and ncoff, the
|
||||
c number of coefficients in the standard b-spline representation.
|
||||
nt4 = nt-4
|
||||
np4 = np-4
|
||||
ncoff = nt4*np4
|
||||
ncof = 6+npp*(ntt-1)
|
||||
c find the bandwidth of the observation matrix a.
|
||||
iband = 4*npp
|
||||
if(ntt.eq.4) iband = 3*(npp+1)
|
||||
if(ntt.lt.4) iband = ncof
|
||||
iband1 = iband-1
|
||||
c initialize the observation matrix a.
|
||||
do 160 i=1,ncof
|
||||
f(i) = 0.
|
||||
do 160 j=1,iband
|
||||
a(i,j) = 0.
|
||||
160 continue
|
||||
c initialize the sum of squared residuals.
|
||||
fp = 0.
|
||||
c fetch the data points in the new order. main loop for the
|
||||
c different panels.
|
||||
do 340 num=1,nreg
|
||||
c fix certain constants for the current panel; jrot records the column
|
||||
c number of the first non-zero element in a row of the observation
|
||||
c matrix according to a data point of the panel.
|
||||
num1 = num-1
|
||||
lt = num1/npp
|
||||
l1 = lt+4
|
||||
lp = num1-lt*npp+1
|
||||
l2 = lp+3
|
||||
lt = lt+1
|
||||
jrot = 0
|
||||
if(lt.gt.2) jrot = 3+(lt-3)*npp
|
||||
c test whether there are still data points in the current panel.
|
||||
in = index(num)
|
||||
170 if(in.eq.0) go to 340
|
||||
c fetch a new data point.
|
||||
wi = w(in)
|
||||
ri = r(in)*wi
|
||||
c evaluate for the teta-direction, the 4 non-zero b-splines at teta(in)
|
||||
call fpbspl(tt,nt,3,teta(in),l1,ht)
|
||||
c evaluate for the phi-direction, the 4 non-zero b-splines at phi(in)
|
||||
call fpbspl(tp,np,3,phi(in),l2,hp)
|
||||
c store the value of these b-splines in spt and spp resp.
|
||||
do 180 i=1,4
|
||||
spp(in,i) = hp(i)
|
||||
spt(in,i) = ht(i)
|
||||
180 continue
|
||||
c initialize the new row of observation matrix.
|
||||
do 190 i=1,iband
|
||||
h(i) = 0.
|
||||
190 continue
|
||||
c calculate the non-zero elements of the new row by making the cross
|
||||
c products of the non-zero b-splines in teta- and phi-direction and
|
||||
c by taking into account the conditions of the spherical splines.
|
||||
do 200 i=1,npp
|
||||
row(i) = 0.
|
||||
200 continue
|
||||
c take into account the condition (3) of the spherical splines.
|
||||
ll = lp
|
||||
do 210 i=1,4
|
||||
if(ll.gt.npp) ll=1
|
||||
row(ll) = row(ll)+hp(i)
|
||||
ll = ll+1
|
||||
210 continue
|
||||
c take into account the other conditions of the spherical splines.
|
||||
if(lt.gt.2 .and. lt.lt.(ntt-1)) go to 230
|
||||
facc = 0.
|
||||
facs = 0.
|
||||
do 220 i=1,npp
|
||||
facc = facc+row(i)*coco(i)
|
||||
facs = facs+row(i)*cosi(i)
|
||||
220 continue
|
||||
c fill in the non-zero elements of the new row.
|
||||
230 j1 = 0
|
||||
do 280 j =1,4
|
||||
jlt = j+lt
|
||||
htj = ht(j)
|
||||
if(jlt.gt.2 .and. jlt.le.nt4) go to 240
|
||||
j1 = j1+1
|
||||
h(j1) = h(j1)+htj
|
||||
go to 280
|
||||
240 if(jlt.eq.3 .or. jlt.eq.nt4) go to 260
|
||||
do 250 i=1,npp
|
||||
j1 = j1+1
|
||||
h(j1) = row(i)*htj
|
||||
250 continue
|
||||
go to 280
|
||||
260 if(jlt.eq.3) go to 270
|
||||
h(j1+1) = facc*htj
|
||||
h(j1+2) = facs*htj
|
||||
h(j1+3) = htj
|
||||
j1 = j1+2
|
||||
go to 280
|
||||
270 h(1) = h(1)+htj
|
||||
h(2) = facc*htj
|
||||
h(3) = facs*htj
|
||||
j1 = 3
|
||||
280 continue
|
||||
do 290 i=1,iband
|
||||
h(i) = h(i)*wi
|
||||
290 continue
|
||||
c rotate the row into triangle by givens transformations.
|
||||
irot = jrot
|
||||
do 310 i=1,iband
|
||||
irot = irot+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 310
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a(irot,1),co,si)
|
||||
c apply that transformation to the right hand side.
|
||||
call fprota(co,si,ri,f(irot))
|
||||
if(i.eq.iband) go to 320
|
||||
c apply that transformation to the left hand side.
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 300 j=i3,iband
|
||||
i2 = i2+1
|
||||
call fprota(co,si,h(j),a(irot,i2))
|
||||
300 continue
|
||||
310 continue
|
||||
c add the contribution of the row to the sum of squares of residual
|
||||
c right hand sides.
|
||||
320 fp = fp+ri**2
|
||||
c find the number of the next data point in the panel.
|
||||
in = nummer(in)
|
||||
go to 170
|
||||
340 continue
|
||||
c find dmax, the maximum value for the diagonal elements in the reduced
|
||||
c triangle.
|
||||
dmax = 0.
|
||||
do 350 i=1,ncof
|
||||
if(a(i,1).le.dmax) go to 350
|
||||
dmax = a(i,1)
|
||||
350 continue
|
||||
c check whether the observation matrix is rank deficient.
|
||||
sigma = eps*dmax
|
||||
do 360 i=1,ncof
|
||||
if(a(i,1).le.sigma) go to 370
|
||||
360 continue
|
||||
c backward substitution in case of full rank.
|
||||
call fpback(a,f,ncof,iband,c,ncc)
|
||||
rank = ncof
|
||||
do 365 i=1,ncof
|
||||
q(i,1) = a(i,1)/dmax
|
||||
365 continue
|
||||
go to 390
|
||||
c in case of rank deficiency, find the minimum norm solution.
|
||||
370 lwest = ncof*iband+ncof+iband
|
||||
if(lwrk.lt.lwest) go to 925
|
||||
lf = 1
|
||||
lh = lf+ncof
|
||||
la = lh+iband
|
||||
do 380 i=1,ncof
|
||||
ff(i) = f(i)
|
||||
do 380 j=1,iband
|
||||
q(i,j) = a(i,j)
|
||||
380 continue
|
||||
call fprank(q,ff,ncof,iband,ncc,sigma,c,sq,rank,wrk(la),
|
||||
* wrk(lf),wrk(lh))
|
||||
do 385 i=1,ncof
|
||||
q(i,1) = q(i,1)/dmax
|
||||
385 continue
|
||||
c add to the sum of squared residuals, the contribution of reducing
|
||||
c the rank.
|
||||
fp = fp+sq
|
||||
c find the coefficients in the standard b-spline representation of
|
||||
c the spherical spline.
|
||||
390 call fprpsp(nt,np,coco,cosi,c,ff,ncoff)
|
||||
c test whether the least-squares spline is an acceptable solution.
|
||||
if(iopt.lt.0) then
|
||||
if (fp.le.0) go to 970
|
||||
go to 980
|
||||
endif
|
||||
fpms = fp-s
|
||||
if(abs(fpms).le.acc) then
|
||||
if (fp.le.0) go to 970
|
||||
go to 980
|
||||
endif
|
||||
c if f(p=inf) < s, accept the choice of knots.
|
||||
if(fpms.lt.0.) go to 580
|
||||
c test whether we cannot further increase the number of knots.
|
||||
if(ncof.gt.m) go to 935
|
||||
c search where to add a new knot.
|
||||
c find for each interval the sum of squared residuals fpint for the
|
||||
c data points having the coordinate belonging to that knot interval.
|
||||
c calculate also coord which is the same sum, weighted by the position
|
||||
c of the data points considered.
|
||||
do 450 i=1,nrint
|
||||
fpint(i) = 0.
|
||||
coord(i) = 0.
|
||||
450 continue
|
||||
do 490 num=1,nreg
|
||||
num1 = num-1
|
||||
lt = num1/npp
|
||||
l1 = lt+1
|
||||
lp = num1-lt*npp
|
||||
l2 = lp+1+ntt
|
||||
jrot = lt*np4+lp
|
||||
in = index(num)
|
||||
460 if(in.eq.0) go to 490
|
||||
store = 0.
|
||||
i1 = jrot
|
||||
do 480 i=1,4
|
||||
hti = spt(in,i)
|
||||
j1 = i1
|
||||
do 470 j=1,4
|
||||
j1 = j1+1
|
||||
store = store+hti*spp(in,j)*c(j1)
|
||||
470 continue
|
||||
i1 = i1+np4
|
||||
480 continue
|
||||
store = (w(in)*(r(in)-store))**2
|
||||
fpint(l1) = fpint(l1)+store
|
||||
coord(l1) = coord(l1)+store*teta(in)
|
||||
fpint(l2) = fpint(l2)+store
|
||||
coord(l2) = coord(l2)+store*phi(in)
|
||||
in = nummer(in)
|
||||
go to 460
|
||||
490 continue
|
||||
c find the interval for which fpint is maximal on the condition that
|
||||
c there still can be added a knot.
|
||||
l1 = 1
|
||||
l2 = nrint
|
||||
if(ntest.lt.nt+1) l1=ntt+1
|
||||
if(npest.lt.np+2) l2=ntt
|
||||
c test whether we cannot further increase the number of knots.
|
||||
if(l1.gt.l2) go to 950
|
||||
500 fpmax = 0.
|
||||
l = 0
|
||||
do 510 i=l1,l2
|
||||
if(fpmax.ge.fpint(i)) go to 510
|
||||
l = i
|
||||
fpmax = fpint(i)
|
||||
510 continue
|
||||
if(l.eq.0) go to 930
|
||||
c calculate the position of the new knot.
|
||||
arg = coord(l)/fpint(l)
|
||||
c test in what direction the new knot is going to be added.
|
||||
if(l.gt.ntt) go to 530
|
||||
c addition in the teta-direction
|
||||
l4 = l+4
|
||||
fpint(l) = 0.
|
||||
fac1 = tt(l4)-arg
|
||||
fac2 = arg-tt(l4-1)
|
||||
if(fac1.gt.(ten*fac2) .or. fac2.gt.(ten*fac1)) go to 500
|
||||
j = nt
|
||||
do 520 i=l4,nt
|
||||
tt(j+1) = tt(j)
|
||||
j = j-1
|
||||
520 continue
|
||||
tt(l4) = arg
|
||||
nt = nt+1
|
||||
go to 570
|
||||
c addition in the phi-direction
|
||||
530 l4 = l+4-ntt
|
||||
if(arg.lt.pi) go to 540
|
||||
arg = arg-pi
|
||||
l4 = l4-nrr
|
||||
540 fpint(l) = 0.
|
||||
fac1 = tp(l4)-arg
|
||||
fac2 = arg-tp(l4-1)
|
||||
if(fac1.gt.(ten*fac2) .or. fac2.gt.(ten*fac1)) go to 500
|
||||
ll = nrr+4
|
||||
j = ll
|
||||
do 550 i=l4,ll
|
||||
tp(j+1) = tp(j)
|
||||
j = j-1
|
||||
550 continue
|
||||
tp(l4) = arg
|
||||
np = np+2
|
||||
nrr = nrr+1
|
||||
do 560 i=5,ll
|
||||
j = i+nrr
|
||||
tp(j) = tp(i)+pi
|
||||
560 continue
|
||||
c restart the computations with the new set of knots.
|
||||
570 continue
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 2: determination of the smoothing spherical spline. c
|
||||
c ******************************************************** c
|
||||
c we have determined the number of knots and their position. we now c
|
||||
c compute the coefficients of the smoothing spline sp(teta,phi). c
|
||||
c the observation matrix a is extended by the rows of a matrix, expres-c
|
||||
c sing that sp(teta,phi) must be a constant function in the variable c
|
||||
c phi and a cubic polynomial in the variable teta. the corresponding c
|
||||
c weights of these additional rows are set to 1/(p). iteratively c
|
||||
c we than have to determine the value of p such that f(p) = sum((w(i)* c
|
||||
c (r(i)-sp(teta(i),phi(i))))**2) be = s. c
|
||||
c we already know that the least-squares polynomial corresponds to p=0,c
|
||||
c and that the least-squares spherical spline corresponds to p=infin. c
|
||||
c the iteration process makes use of rational interpolation. since f(p)c
|
||||
c is a convex and strictly decreasing function of p, it can be approx- c
|
||||
c imated by a rational function of the form r(p) = (u*p+v)/(p+w). c
|
||||
c three values of p (p1,p2,p3) with corresponding values of f(p) (f1= c
|
||||
c f(p1)-s,f2=f(p2)-s,f3=f(p3)-s) are used to calculate the new value c
|
||||
c of p such that r(p)=s. convergence is guaranteed by taking f1>0,f3<0.c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c evaluate the discontinuity jumps of the 3-th order derivative of
|
||||
c the b-splines at the knots tt(l),l=5,...,nt-4.
|
||||
580 call fpdisc(tt,nt,5,bt,ntest)
|
||||
c evaluate the discontinuity jumps of the 3-th order derivative of
|
||||
c the b-splines at the knots tp(l),l=5,...,np-4.
|
||||
call fpdisc(tp,np,5,bp,npest)
|
||||
c initial value for p.
|
||||
p1 = 0.
|
||||
f1 = sup-s
|
||||
p3 = -one
|
||||
f3 = fpms
|
||||
p = 0.
|
||||
do 585 i=1,ncof
|
||||
p = p+a(i,1)
|
||||
585 continue
|
||||
rn = ncof
|
||||
p = rn/p
|
||||
c find the bandwidth of the extended observation matrix.
|
||||
iband4 = iband+3
|
||||
if(ntt.le.4) iband4 = ncof
|
||||
iband3 = iband4 -1
|
||||
ich1 = 0
|
||||
ich3 = 0
|
||||
c iteration process to find the root of f(p)=s.
|
||||
do 920 iter=1,maxit
|
||||
pinv = one/p
|
||||
c store the triangularized observation matrix into q.
|
||||
do 600 i=1,ncof
|
||||
ff(i) = f(i)
|
||||
do 590 j=1,iband4
|
||||
q(i,j) = 0.
|
||||
590 continue
|
||||
do 600 j=1,iband
|
||||
q(i,j) = a(i,j)
|
||||
600 continue
|
||||
c extend the observation matrix with the rows of a matrix, expressing
|
||||
c that for teta=cst. sp(teta,phi) must be a constant function.
|
||||
nt6 = nt-6
|
||||
do 720 i=5,np4
|
||||
ii = i-4
|
||||
do 610 l=1,npp
|
||||
row(l) = 0.
|
||||
610 continue
|
||||
ll = ii
|
||||
do 620 l=1,5
|
||||
if(ll.gt.npp) ll=1
|
||||
row(ll) = row(ll)+bp(ii,l)
|
||||
ll = ll+1
|
||||
620 continue
|
||||
facc = 0.
|
||||
facs = 0.
|
||||
do 630 l=1,npp
|
||||
facc = facc+row(l)*coco(l)
|
||||
facs = facs+row(l)*cosi(l)
|
||||
630 continue
|
||||
do 720 j=1,nt6
|
||||
c initialize the new row.
|
||||
do 640 l=1,iband
|
||||
h(l) = 0.
|
||||
640 continue
|
||||
c fill in the non-zero elements of the row. jrot records the column
|
||||
c number of the first non-zero element in the row.
|
||||
jrot = 4+(j-2)*npp
|
||||
if(j.gt.1 .and. j.lt.nt6) go to 650
|
||||
h(1) = facc
|
||||
h(2) = facs
|
||||
if(j.eq.1) jrot = 2
|
||||
go to 670
|
||||
650 do 660 l=1,npp
|
||||
h(l)=row(l)
|
||||
660 continue
|
||||
670 do 675 l=1,iband
|
||||
h(l) = h(l)*pinv
|
||||
675 continue
|
||||
ri = 0.
|
||||
c rotate the new row into triangle by givens transformations.
|
||||
do 710 irot=jrot,ncof
|
||||
piv = h(1)
|
||||
i2 = min0(iband1,ncof-irot)
|
||||
if(piv.eq.0.) then
|
||||
if (i2.le.0) go to 720
|
||||
go to 690
|
||||
endif
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,q(irot,1),co,si)
|
||||
c apply that givens transformation to the right hand side.
|
||||
call fprota(co,si,ri,ff(irot))
|
||||
if(i2.eq.0) go to 720
|
||||
c apply that givens transformation to the left hand side.
|
||||
do 680 l=1,i2
|
||||
l1 = l+1
|
||||
call fprota(co,si,h(l1),q(irot,l1))
|
||||
680 continue
|
||||
690 do 700 l=1,i2
|
||||
h(l) = h(l+1)
|
||||
700 continue
|
||||
h(i2+1) = 0.
|
||||
710 continue
|
||||
720 continue
|
||||
c extend the observation matrix with the rows of a matrix expressing
|
||||
c that for phi=cst. sp(teta,phi) must be a cubic polynomial.
|
||||
do 810 i=5,nt4
|
||||
ii = i-4
|
||||
do 810 j=1,npp
|
||||
c initialize the new row
|
||||
do 730 l=1,iband4
|
||||
h(l) = 0.
|
||||
730 continue
|
||||
c fill in the non-zero elements of the row. jrot records the column
|
||||
c number of the first non-zero element in the row.
|
||||
j1 = 1
|
||||
do 760 l=1,5
|
||||
il = ii+l
|
||||
ij = npp
|
||||
if(il.ne.3 .and. il.ne.nt4) go to 750
|
||||
j1 = j1+3-j
|
||||
j2 = j1-2
|
||||
ij = 0
|
||||
if(il.ne.3) go to 740
|
||||
j1 = 1
|
||||
j2 = 2
|
||||
ij = j+2
|
||||
740 h(j2) = bt(ii,l)*coco(j)
|
||||
h(j2+1) = bt(ii,l)*cosi(j)
|
||||
750 h(j1) = h(j1)+bt(ii,l)
|
||||
j1 = j1+ij
|
||||
760 continue
|
||||
do 765 l=1,iband4
|
||||
h(l) = h(l)*pinv
|
||||
765 continue
|
||||
ri = 0.
|
||||
jrot = 1
|
||||
if(ii.gt.2) jrot = 3+j+(ii-3)*npp
|
||||
c rotate the new row into triangle by givens transformations.
|
||||
do 800 irot=jrot,ncof
|
||||
piv = h(1)
|
||||
i2 = min0(iband3,ncof-irot)
|
||||
if(piv.eq.0.) then
|
||||
if (i2.le.0) go to 810
|
||||
go to 780
|
||||
endif
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,q(irot,1),co,si)
|
||||
c apply that givens transformation to the right hand side.
|
||||
call fprota(co,si,ri,ff(irot))
|
||||
if(i2.eq.0) go to 810
|
||||
c apply that givens transformation to the left hand side.
|
||||
do 770 l=1,i2
|
||||
l1 = l+1
|
||||
call fprota(co,si,h(l1),q(irot,l1))
|
||||
770 continue
|
||||
780 do 790 l=1,i2
|
||||
h(l) = h(l+1)
|
||||
790 continue
|
||||
h(i2+1) = 0.
|
||||
800 continue
|
||||
810 continue
|
||||
c find dmax, the maximum value for the diagonal elements in the
|
||||
c reduced triangle.
|
||||
dmax = 0.
|
||||
do 820 i=1,ncof
|
||||
if(q(i,1).le.dmax) go to 820
|
||||
dmax = q(i,1)
|
||||
820 continue
|
||||
c check whether the matrix is rank deficient.
|
||||
sigma = eps*dmax
|
||||
do 830 i=1,ncof
|
||||
if(q(i,1).le.sigma) go to 840
|
||||
830 continue
|
||||
c backward substitution in case of full rank.
|
||||
call fpback(q,ff,ncof,iband4,c,ncc)
|
||||
rank = ncof
|
||||
go to 845
|
||||
c in case of rank deficiency, find the minimum norm solution.
|
||||
840 lwest = ncof*iband4+ncof+iband4
|
||||
if(lwrk.lt.lwest) go to 925
|
||||
lf = 1
|
||||
lh = lf+ncof
|
||||
la = lh+iband4
|
||||
call fprank(q,ff,ncof,iband4,ncc,sigma,c,sq,rank,wrk(la),
|
||||
* wrk(lf),wrk(lh))
|
||||
845 do 850 i=1,ncof
|
||||
q(i,1) = q(i,1)/dmax
|
||||
850 continue
|
||||
c find the coefficients in the standard b-spline representation of
|
||||
c the spherical spline.
|
||||
call fprpsp(nt,np,coco,cosi,c,ff,ncoff)
|
||||
c compute f(p).
|
||||
fp = 0.
|
||||
do 890 num = 1,nreg
|
||||
num1 = num-1
|
||||
lt = num1/npp
|
||||
lp = num1-lt*npp
|
||||
jrot = lt*np4+lp
|
||||
in = index(num)
|
||||
860 if(in.eq.0) go to 890
|
||||
store = 0.
|
||||
i1 = jrot
|
||||
do 880 i=1,4
|
||||
hti = spt(in,i)
|
||||
j1 = i1
|
||||
do 870 j=1,4
|
||||
j1 = j1+1
|
||||
store = store+hti*spp(in,j)*c(j1)
|
||||
870 continue
|
||||
i1 = i1+np4
|
||||
880 continue
|
||||
fp = fp+(w(in)*(r(in)-store))**2
|
||||
in = nummer(in)
|
||||
go to 860
|
||||
890 continue
|
||||
c test whether the approximation sp(teta,phi) is an acceptable solution
|
||||
fpms = fp-s
|
||||
if(abs(fpms).le.acc) go to 980
|
||||
c test whether the maximum allowable number of iterations has been
|
||||
c reached.
|
||||
if(iter.eq.maxit) go to 940
|
||||
c carry out one more step of the iteration process.
|
||||
p2 = p
|
||||
f2 = fpms
|
||||
if(ich3.ne.0) go to 900
|
||||
if((f2-f3).gt.acc) go to 895
|
||||
c our initial choice of p is too large.
|
||||
p3 = p2
|
||||
f3 = f2
|
||||
p = p*con4
|
||||
if(p.le.p1) p = p1*con9 + p2*con1
|
||||
go to 920
|
||||
895 if(f2.lt.0.) ich3 = 1
|
||||
900 if(ich1.ne.0) go to 910
|
||||
if((f1-f2).gt.acc) go to 905
|
||||
c our initial choice of p is too small
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
p = p/con4
|
||||
if(p3.lt.0.) go to 920
|
||||
if(p.ge.p3) p = p2*con1 +p3*con9
|
||||
go to 920
|
||||
905 if(f2.gt.0.) ich1 = 1
|
||||
c test whether the iteration process proceeds as theoretically
|
||||
c expected.
|
||||
910 if(f2.ge.f1 .or. f2.le.f3) go to 945
|
||||
c find the new value of p.
|
||||
p = fprati(p1,f1,p2,f2,p3,f3)
|
||||
920 continue
|
||||
c error codes and messages.
|
||||
925 ier = lwest
|
||||
go to 990
|
||||
930 ier = 5
|
||||
go to 990
|
||||
935 ier = 4
|
||||
go to 990
|
||||
940 ier = 3
|
||||
go to 990
|
||||
945 ier = 2
|
||||
go to 990
|
||||
950 ier = 1
|
||||
go to 990
|
||||
960 ier = -2
|
||||
go to 990
|
||||
970 ier = -1
|
||||
fp = 0.
|
||||
980 if(ncof.ne.rank) ier = -rank
|
||||
990 return
|
||||
end
|
||||
82
cxx/fitpack/fpsuev.f
Normal file
82
cxx/fitpack/fpsuev.f
Normal file
@ -0,0 +1,82 @@
|
||||
recursive subroutine fpsuev(idim,tu,nu,tv,nv,c,u,mu,v,mv,f,
|
||||
* wu,wv,lu,lv)
|
||||
implicit none
|
||||
c ..scalar arguments..
|
||||
integer idim,nu,nv,mu,mv
|
||||
c ..array arguments..
|
||||
integer lu(mu),lv(mv)
|
||||
real*8 tu(nu),tv(nv),c((nu-4)*(nv-4)*idim),u(mu),v(mv),
|
||||
* f(mu*mv*idim),wu(mu,4),wv(mv,4)
|
||||
c ..local scalars..
|
||||
integer i,i1,j,j1,k,l,l1,l2,l3,m,nuv,nu4,nv4
|
||||
real*8 arg,sp,tb,te
|
||||
c ..local arrays..
|
||||
real*8 h(4)
|
||||
c ..subroutine references..
|
||||
c fpbspl
|
||||
c ..
|
||||
nu4 = nu-4
|
||||
tb = tu(4)
|
||||
te = tu(nu4+1)
|
||||
l = 4
|
||||
l1 = l+1
|
||||
do 40 i=1,mu
|
||||
arg = u(i)
|
||||
if(arg.lt.tb) arg = tb
|
||||
if(arg.gt.te) arg = te
|
||||
10 if(arg.lt.tu(l1) .or. l.eq.nu4) go to 20
|
||||
l = l1
|
||||
l1 = l+1
|
||||
go to 10
|
||||
20 call fpbspl(tu,nu,3,arg,l,h)
|
||||
lu(i) = l-4
|
||||
do 30 j=1,4
|
||||
wu(i,j) = h(j)
|
||||
30 continue
|
||||
40 continue
|
||||
nv4 = nv-4
|
||||
tb = tv(4)
|
||||
te = tv(nv4+1)
|
||||
l = 4
|
||||
l1 = l+1
|
||||
do 80 i=1,mv
|
||||
arg = v(i)
|
||||
if(arg.lt.tb) arg = tb
|
||||
if(arg.gt.te) arg = te
|
||||
50 if(arg.lt.tv(l1) .or. l.eq.nv4) go to 60
|
||||
l = l1
|
||||
l1 = l+1
|
||||
go to 50
|
||||
60 call fpbspl(tv,nv,3,arg,l,h)
|
||||
lv(i) = l-4
|
||||
do 70 j=1,4
|
||||
wv(i,j) = h(j)
|
||||
70 continue
|
||||
80 continue
|
||||
m = 0
|
||||
nuv = nu4*nv4
|
||||
do 140 k=1,idim
|
||||
l3 = (k-1)*nuv
|
||||
do 130 i=1,mu
|
||||
l = lu(i)*nv4+l3
|
||||
do 90 i1=1,4
|
||||
h(i1) = wu(i,i1)
|
||||
90 continue
|
||||
do 120 j=1,mv
|
||||
l1 = l+lv(j)
|
||||
sp = 0.
|
||||
do 110 i1=1,4
|
||||
l2 = l1
|
||||
do 100 j1=1,4
|
||||
l2 = l2+1
|
||||
sp = sp+c(l2)*h(i1)*wv(j,j1)
|
||||
100 continue
|
||||
l1 = l1+nv4
|
||||
110 continue
|
||||
m = m+1
|
||||
f(m) = sp
|
||||
120 continue
|
||||
130 continue
|
||||
140 continue
|
||||
return
|
||||
end
|
||||
681
cxx/fitpack/fpsurf.f
Normal file
681
cxx/fitpack/fpsurf.f
Normal file
@ -0,0 +1,681 @@
|
||||
recursive subroutine fpsurf(iopt,m,x,y,z,w,xb,xe,yb,ye,kxx,kyy,
|
||||
* s,nxest, nyest,eta,tol,maxit,nmax,km1,km2,ib1,ib3,nc,intest,
|
||||
* nrest,nx0,tx,ny0,ty,c,fp,fp0,fpint,coord,f,ff,a,q,bx,by,spx,
|
||||
* spy,h,index,nummer,wrk,lwrk,ier)
|
||||
implicit none
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 xb,xe,yb,ye,s,eta,tol,fp,fp0
|
||||
integer iopt,m,kxx,kyy,nxest,nyest,maxit,nmax,km1,km2,ib1,ib3,
|
||||
* nc,intest,nrest,nx0,ny0,lwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),y(m),z(m),w(m),tx(nmax),ty(nmax),c(nc),fpint(intest),
|
||||
* coord(intest),f(nc),ff(nc),a(nc,ib1),q(nc,ib3),bx(nmax,km2),
|
||||
* by(nmax,km2),spx(m,km1),spy(m,km1),h(ib3),wrk(lwrk)
|
||||
integer index(nrest),nummer(m)
|
||||
c ..local scalars..
|
||||
real*8 acc,arg,cos,dmax,fac1,fac2,fpmax,fpms,f1,f2,f3,hxi,p,pinv,
|
||||
* piv,p1,p2,p3,sigma,sin,sq,store,wi,x0,x1,y0,y1,zi,eps,
|
||||
* rn,one,con1,con9,con4,half,ten
|
||||
integer i,iband,iband1,iband3,iband4,ibb,ichang,ich1,ich3,ii,
|
||||
* in,irot,iter,i1,i2,i3,j,jrot,jxy,j1,kx,kx1,kx2,ky,ky1,ky2,l,
|
||||
* la,lf,lh,lwest,lx,ly,l1,l2,n,ncof,nk1x,nk1y,nminx,nminy,nreg,
|
||||
* nrint,num,num1,nx,nxe,nxx,ny,nye,nyy,n1,rank
|
||||
c ..local arrays..
|
||||
real*8 hx(6),hy(6)
|
||||
c ..function references..
|
||||
real*8 abs,fprati,sqrt
|
||||
integer min0
|
||||
c ..subroutine references..
|
||||
c fpback,fpbspl,fpgivs,fpdisc,fporde,fprank,fprota
|
||||
c ..
|
||||
c set constants
|
||||
one = 0.1e+01
|
||||
con1 = 0.1e0
|
||||
con9 = 0.9e0
|
||||
con4 = 0.4e-01
|
||||
half = 0.5e0
|
||||
ten = 0.1e+02
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 1: determination of the number of knots and their position. c
|
||||
c **************************************************************** c
|
||||
c given a set of knots we compute the least-squares spline sinf(x,y), c
|
||||
c and the corresponding weighted sum of squared residuals fp=f(p=inf). c
|
||||
c if iopt=-1 sinf(x,y) is the requested approximation. c
|
||||
c if iopt=0 or iopt=1 we check whether we can accept the knots: c
|
||||
c if fp <=s we will continue with the current set of knots. c
|
||||
c if fp > s we will increase the number of knots and compute the c
|
||||
c corresponding least-squares spline until finally fp<=s. c
|
||||
c the initial choice of knots depends on the value of s and iopt. c
|
||||
c if iopt=0 we first compute the least-squares polynomial of degree c
|
||||
c kx in x and ky in y; nx=nminx=2*kx+2 and ny=nminy=2*ky+2. c
|
||||
c fp0=f(0) denotes the corresponding weighted sum of squared c
|
||||
c residuals c
|
||||
c if iopt=1 we start with the knots found at the last call of the c
|
||||
c routine, except for the case that s>=fp0; then we can compute c
|
||||
c the least-squares polynomial directly. c
|
||||
c eventually the independent variables x and y (and the corresponding c
|
||||
c parameters) will be switched if this can reduce the bandwidth of the c
|
||||
c system to be solved. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c ichang denotes whether(1) or not(-1) the directions have been inter-
|
||||
c changed.
|
||||
ichang = -1
|
||||
x0 = xb
|
||||
x1 = xe
|
||||
y0 = yb
|
||||
y1 = ye
|
||||
kx = kxx
|
||||
ky = kyy
|
||||
kx1 = kx+1
|
||||
ky1 = ky+1
|
||||
nxe = nxest
|
||||
nye = nyest
|
||||
eps = sqrt(eta)
|
||||
if(iopt.lt.0) go to 20
|
||||
c calculation of acc, the absolute tolerance for the root of f(p)=s.
|
||||
acc = tol*s
|
||||
if(iopt.eq.0) go to 10
|
||||
if(fp0.gt.s) go to 20
|
||||
c initialization for the least-squares polynomial.
|
||||
10 nminx = 2*kx1
|
||||
nminy = 2*ky1
|
||||
nx = nminx
|
||||
ny = nminy
|
||||
ier = -2
|
||||
go to 30
|
||||
20 nx = nx0
|
||||
ny = ny0
|
||||
c main loop for the different sets of knots. m is a save upper bound
|
||||
c for the number of trials.
|
||||
30 do 420 iter=1,m
|
||||
c find the position of the additional knots which are needed for the
|
||||
c b-spline representation of s(x,y).
|
||||
l = nx
|
||||
do 40 i=1,kx1
|
||||
tx(i) = x0
|
||||
tx(l) = x1
|
||||
l = l-1
|
||||
40 continue
|
||||
l = ny
|
||||
do 50 i=1,ky1
|
||||
ty(i) = y0
|
||||
ty(l) = y1
|
||||
l = l-1
|
||||
50 continue
|
||||
c find nrint, the total number of knot intervals and nreg, the number
|
||||
c of panels in which the approximation domain is subdivided by the
|
||||
c intersection of knots.
|
||||
nxx = nx-2*kx1+1
|
||||
nyy = ny-2*ky1+1
|
||||
nrint = nxx+nyy
|
||||
nreg = nxx*nyy
|
||||
c find the bandwidth of the observation matrix a.
|
||||
c if necessary, interchange the variables x and y, in order to obtain
|
||||
c a minimal bandwidth.
|
||||
iband1 = kx*(ny-ky1)+ky
|
||||
l = ky*(nx-kx1)+kx
|
||||
if(iband1.le.l) go to 130
|
||||
iband1 = l
|
||||
ichang = -ichang
|
||||
do 60 i=1,m
|
||||
store = x(i)
|
||||
x(i) = y(i)
|
||||
y(i) = store
|
||||
60 continue
|
||||
store = x0
|
||||
x0 = y0
|
||||
y0 = store
|
||||
store = x1
|
||||
x1 = y1
|
||||
y1 = store
|
||||
n = min0(nx,ny)
|
||||
do 70 i=1,n
|
||||
store = tx(i)
|
||||
tx(i) = ty(i)
|
||||
ty(i) = store
|
||||
70 continue
|
||||
n1 = n+1
|
||||
if (nx.lt.ny) go to 80
|
||||
if (nx.eq.ny) go to 120
|
||||
go to 100
|
||||
80 do 90 i=n1,ny
|
||||
tx(i) = ty(i)
|
||||
90 continue
|
||||
go to 120
|
||||
100 do 110 i=n1,nx
|
||||
ty(i) = tx(i)
|
||||
110 continue
|
||||
120 l = nx
|
||||
nx = ny
|
||||
ny = l
|
||||
l = nxe
|
||||
nxe = nye
|
||||
nye = l
|
||||
l = nxx
|
||||
nxx = nyy
|
||||
nyy = l
|
||||
l = kx
|
||||
kx = ky
|
||||
ky = l
|
||||
kx1 = kx+1
|
||||
ky1 = ky+1
|
||||
130 iband = iband1+1
|
||||
c arrange the data points according to the panel they belong to.
|
||||
call fporde(x,y,m,kx,ky,tx,nx,ty,ny,nummer,index,nreg)
|
||||
c find ncof, the number of b-spline coefficients.
|
||||
nk1x = nx-kx1
|
||||
nk1y = ny-ky1
|
||||
ncof = nk1x*nk1y
|
||||
c initialize the observation matrix a.
|
||||
do 140 i=1,ncof
|
||||
f(i) = 0.
|
||||
do 140 j=1,iband
|
||||
a(i,j) = 0.
|
||||
140 continue
|
||||
c initialize the sum of squared residuals.
|
||||
fp = 0.
|
||||
c fetch the data points in the new order. main loop for the
|
||||
c different panels.
|
||||
do 250 num=1,nreg
|
||||
c fix certain constants for the current panel; jrot records the column
|
||||
c number of the first non-zero element in a row of the observation
|
||||
c matrix according to a data point of the panel.
|
||||
num1 = num-1
|
||||
lx = num1/nyy
|
||||
l1 = lx+kx1
|
||||
ly = num1-lx*nyy
|
||||
l2 = ly+ky1
|
||||
jrot = lx*nk1y+ly
|
||||
c test whether there are still data points in the panel.
|
||||
in = index(num)
|
||||
150 if(in.eq.0) go to 250
|
||||
c fetch a new data point.
|
||||
wi = w(in)
|
||||
zi = z(in)*wi
|
||||
c evaluate for the x-direction, the (kx+1) non-zero b-splines at x(in).
|
||||
call fpbspl(tx,nx,kx,x(in),l1,hx)
|
||||
c evaluate for the y-direction, the (ky+1) non-zero b-splines at y(in).
|
||||
call fpbspl(ty,ny,ky,y(in),l2,hy)
|
||||
c store the value of these b-splines in spx and spy respectively.
|
||||
do 160 i=1,kx1
|
||||
spx(in,i) = hx(i)
|
||||
160 continue
|
||||
do 170 i=1,ky1
|
||||
spy(in,i) = hy(i)
|
||||
170 continue
|
||||
c initialize the new row of observation matrix.
|
||||
do 180 i=1,iband
|
||||
h(i) = 0.
|
||||
180 continue
|
||||
c calculate the non-zero elements of the new row by making the cross
|
||||
c products of the non-zero b-splines in x- and y-direction.
|
||||
i1 = 0
|
||||
do 200 i=1,kx1
|
||||
hxi = hx(i)
|
||||
j1 = i1
|
||||
do 190 j=1,ky1
|
||||
j1 = j1+1
|
||||
h(j1) = hxi*hy(j)*wi
|
||||
190 continue
|
||||
i1 = i1+nk1y
|
||||
200 continue
|
||||
c rotate the row into triangle by givens transformations .
|
||||
irot = jrot
|
||||
do 220 i=1,iband
|
||||
irot = irot+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 220
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a(irot,1),cos,sin)
|
||||
c apply that transformation to the right hand side.
|
||||
call fprota(cos,sin,zi,f(irot))
|
||||
if(i.eq.iband) go to 230
|
||||
c apply that transformation to the left hand side.
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 210 j=i3,iband
|
||||
i2 = i2+1
|
||||
call fprota(cos,sin,h(j),a(irot,i2))
|
||||
210 continue
|
||||
220 continue
|
||||
c add the contribution of the row to the sum of squares of residual
|
||||
c right hand sides.
|
||||
230 fp = fp+zi**2
|
||||
c find the number of the next data point in the panel.
|
||||
in = nummer(in)
|
||||
go to 150
|
||||
250 continue
|
||||
c find dmax, the maximum value for the diagonal elements in the reduced
|
||||
c triangle.
|
||||
dmax = 0.
|
||||
do 260 i=1,ncof
|
||||
if(a(i,1).le.dmax) go to 260
|
||||
dmax = a(i,1)
|
||||
260 continue
|
||||
c check whether the observation matrix is rank deficient.
|
||||
sigma = eps*dmax
|
||||
do 270 i=1,ncof
|
||||
if(a(i,1).le.sigma) go to 280
|
||||
270 continue
|
||||
c backward substitution in case of full rank.
|
||||
call fpback(a,f,ncof,iband,c,nc)
|
||||
rank = ncof
|
||||
do 275 i=1,ncof
|
||||
q(i,1) = a(i,1)/dmax
|
||||
275 continue
|
||||
go to 300
|
||||
c in case of rank deficiency, find the minimum norm solution.
|
||||
c check whether there is sufficient working space
|
||||
280 lwest = ncof*iband+ncof+iband
|
||||
if(lwrk.lt.lwest) go to 780
|
||||
do 290 i=1,ncof
|
||||
ff(i) = f(i)
|
||||
do 290 j=1,iband
|
||||
q(i,j) = a(i,j)
|
||||
290 continue
|
||||
lf =1
|
||||
lh = lf+ncof
|
||||
la = lh+iband
|
||||
call fprank(q,ff,ncof,iband,nc,sigma,c,sq,rank,wrk(la),
|
||||
* wrk(lf),wrk(lh))
|
||||
do 295 i=1,ncof
|
||||
q(i,1) = q(i,1)/dmax
|
||||
295 continue
|
||||
c add to the sum of squared residuals, the contribution of reducing
|
||||
c the rank.
|
||||
fp = fp+sq
|
||||
300 if(ier.eq.(-2)) fp0 = fp
|
||||
c test whether the least-squares spline is an acceptable solution.
|
||||
if(iopt.lt.0) go to 820
|
||||
fpms = fp-s
|
||||
if(abs(fpms).le.acc) then
|
||||
if (fp.le.0) go to 815
|
||||
go to 820
|
||||
endif
|
||||
c test whether we can accept the choice of knots.
|
||||
if(fpms.lt.0.) go to 430
|
||||
c test whether we cannot further increase the number of knots.
|
||||
if(ncof.gt.m) go to 790
|
||||
ier = 0
|
||||
c search where to add a new knot.
|
||||
c find for each interval the sum of squared residuals fpint for the
|
||||
c data points having the coordinate belonging to that knot interval.
|
||||
c calculate also coord which is the same sum, weighted by the position
|
||||
c of the data points considered.
|
||||
do 320 i=1,nrint
|
||||
fpint(i) = 0.
|
||||
coord(i) = 0.
|
||||
320 continue
|
||||
do 360 num=1,nreg
|
||||
num1 = num-1
|
||||
lx = num1/nyy
|
||||
l1 = lx+1
|
||||
ly = num1-lx*nyy
|
||||
l2 = ly+1+nxx
|
||||
jrot = lx*nk1y+ly
|
||||
in = index(num)
|
||||
330 if(in.eq.0) go to 360
|
||||
store = 0.
|
||||
i1 = jrot
|
||||
do 350 i=1,kx1
|
||||
hxi = spx(in,i)
|
||||
j1 = i1
|
||||
do 340 j=1,ky1
|
||||
j1 = j1+1
|
||||
store = store+hxi*spy(in,j)*c(j1)
|
||||
340 continue
|
||||
i1 = i1+nk1y
|
||||
350 continue
|
||||
store = (w(in)*(z(in)-store))**2
|
||||
fpint(l1) = fpint(l1)+store
|
||||
coord(l1) = coord(l1)+store*x(in)
|
||||
fpint(l2) = fpint(l2)+store
|
||||
coord(l2) = coord(l2)+store*y(in)
|
||||
in = nummer(in)
|
||||
go to 330
|
||||
360 continue
|
||||
c find the interval for which fpint is maximal on the condition that
|
||||
c there still can be added a knot.
|
||||
370 l = 0
|
||||
fpmax = 0.
|
||||
l1 = 1
|
||||
l2 = nrint
|
||||
if(nx.eq.nxe) l1 = nxx+1
|
||||
if(ny.eq.nye) l2 = nxx
|
||||
if(l1.gt.l2) go to 810
|
||||
do 380 i=l1,l2
|
||||
if(fpmax.ge.fpint(i)) go to 380
|
||||
l = i
|
||||
fpmax = fpint(i)
|
||||
380 continue
|
||||
c test whether we cannot further increase the number of knots.
|
||||
if(l.eq.0) go to 785
|
||||
c calculate the position of the new knot.
|
||||
arg = coord(l)/fpint(l)
|
||||
c test in what direction the new knot is going to be added.
|
||||
if(l.gt.nxx) go to 400
|
||||
c addition in the x-direction.
|
||||
jxy = l+kx1
|
||||
fpint(l) = 0.
|
||||
fac1 = tx(jxy)-arg
|
||||
fac2 = arg-tx(jxy-1)
|
||||
if(fac1.gt.(ten*fac2) .or. fac2.gt.(ten*fac1)) go to 370
|
||||
j = nx
|
||||
do 390 i=jxy,nx
|
||||
tx(j+1) = tx(j)
|
||||
j = j-1
|
||||
390 continue
|
||||
tx(jxy) = arg
|
||||
nx = nx+1
|
||||
go to 420
|
||||
c addition in the y-direction.
|
||||
400 jxy = l+ky1-nxx
|
||||
fpint(l) = 0.
|
||||
fac1 = ty(jxy)-arg
|
||||
fac2 = arg-ty(jxy-1)
|
||||
if(fac1.gt.(ten*fac2) .or. fac2.gt.(ten*fac1)) go to 370
|
||||
j = ny
|
||||
do 410 i=jxy,ny
|
||||
ty(j+1) = ty(j)
|
||||
j = j-1
|
||||
410 continue
|
||||
ty(jxy) = arg
|
||||
ny = ny+1
|
||||
c restart the computations with the new set of knots.
|
||||
420 continue
|
||||
c test whether the least-squares polynomial is a solution of our
|
||||
c approximation problem.
|
||||
430 if(ier.eq.(-2)) go to 830
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
c part 2: determination of the smoothing spline sp(x,y) c
|
||||
c ***************************************************** c
|
||||
c we have determined the number of knots and their position. we now c
|
||||
c compute the b-spline coefficients of the smoothing spline sp(x,y). c
|
||||
c the observation matrix a is extended by the rows of a matrix, c
|
||||
c expressing that sp(x,y) must be a polynomial of degree kx in x and c
|
||||
c ky in y. the corresponding weights of these additional rows are set c
|
||||
c to 1./p. iteratively we than have to determine the value of p c
|
||||
c such that f(p)=sum((w(i)*(z(i)-sp(x(i),y(i))))**2) be = s. c
|
||||
c we already know that the least-squares polynomial corresponds to c
|
||||
c p=0 and that the least-squares spline corresponds to p=infinity. c
|
||||
c the iteration process which is proposed here makes use of rational c
|
||||
c interpolation. since f(p) is a convex and strictly decreasing c
|
||||
c function of p, it can be approximated by a rational function r(p)= c
|
||||
c (u*p+v)/(p+w). three values of p(p1,p2,p3) with corresponding values c
|
||||
c of f(p) (f1=f(p1)-s,f2=f(p2)-s,f3=f(p3)-s) are used to calculate the c
|
||||
c new value of p such that r(p)=s. convergence is guaranteed by taking c
|
||||
c f1 > 0 and f3 < 0. c
|
||||
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|
||||
kx2 = kx1+1
|
||||
c test whether there are interior knots in the x-direction.
|
||||
if(nk1x.eq.kx1) go to 440
|
||||
c evaluate the discotinuity jumps of the kx-th order derivative of
|
||||
c the b-splines at the knots tx(l),l=kx+2,...,nx-kx-1.
|
||||
call fpdisc(tx,nx,kx2,bx,nmax)
|
||||
440 ky2 = ky1 + 1
|
||||
c test whether there are interior knots in the y-direction.
|
||||
if(nk1y.eq.ky1) go to 450
|
||||
c evaluate the discontinuity jumps of the ky-th order derivative of
|
||||
c the b-splines at the knots ty(l),l=ky+2,...,ny-ky-1.
|
||||
call fpdisc(ty,ny,ky2,by,nmax)
|
||||
c initial value for p.
|
||||
450 p1 = 0.
|
||||
f1 = fp0-s
|
||||
p3 = -one
|
||||
f3 = fpms
|
||||
p = 0.
|
||||
do 460 i=1,ncof
|
||||
p = p+a(i,1)
|
||||
460 continue
|
||||
rn = ncof
|
||||
p = rn/p
|
||||
c find the bandwidth of the extended observation matrix.
|
||||
iband3 = kx1*nk1y
|
||||
iband4 = iband3 +1
|
||||
ich1 = 0
|
||||
ich3 = 0
|
||||
c iteration process to find the root of f(p)=s.
|
||||
do 770 iter=1,maxit
|
||||
pinv = one/p
|
||||
c store the triangularized observation matrix into q.
|
||||
do 480 i=1,ncof
|
||||
ff(i) = f(i)
|
||||
do 470 j=1,iband
|
||||
q(i,j) = a(i,j)
|
||||
470 continue
|
||||
ibb = iband+1
|
||||
do 480 j=ibb,iband4
|
||||
q(i,j) = 0.
|
||||
480 continue
|
||||
if(nk1y.eq.ky1) go to 560
|
||||
c extend the observation matrix with the rows of a matrix, expressing
|
||||
c that for x=cst. sp(x,y) must be a polynomial in y of degree ky.
|
||||
do 550 i=ky2,nk1y
|
||||
ii = i-ky1
|
||||
do 550 j=1,nk1x
|
||||
c initialize the new row.
|
||||
do 490 l=1,iband
|
||||
h(l) = 0.
|
||||
490 continue
|
||||
c fill in the non-zero elements of the row. jrot records the column
|
||||
c number of the first non-zero element in the row.
|
||||
do 500 l=1,ky2
|
||||
h(l) = by(ii,l)*pinv
|
||||
500 continue
|
||||
zi = 0.
|
||||
jrot = (j-1)*nk1y+ii
|
||||
c rotate the new row into triangle by givens transformations without
|
||||
c square roots.
|
||||
do 540 irot=jrot,ncof
|
||||
piv = h(1)
|
||||
i2 = min0(iband1,ncof-irot)
|
||||
if(piv.eq.0.) then
|
||||
if (i2.le.0) go to 550
|
||||
go to 520
|
||||
endif
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,q(irot,1),cos,sin)
|
||||
c apply that givens transformation to the right hand side.
|
||||
call fprota(cos,sin,zi,ff(irot))
|
||||
if(i2.eq.0) go to 550
|
||||
c apply that givens transformation to the left hand side.
|
||||
do 510 l=1,i2
|
||||
l1 = l+1
|
||||
call fprota(cos,sin,h(l1),q(irot,l1))
|
||||
510 continue
|
||||
520 do 530 l=1,i2
|
||||
h(l) = h(l+1)
|
||||
530 continue
|
||||
h(i2+1) = 0.
|
||||
540 continue
|
||||
550 continue
|
||||
560 if(nk1x.eq.kx1) go to 640
|
||||
c extend the observation matrix with the rows of a matrix expressing
|
||||
c that for y=cst. sp(x,y) must be a polynomial in x of degree kx.
|
||||
do 630 i=kx2,nk1x
|
||||
ii = i-kx1
|
||||
do 630 j=1,nk1y
|
||||
c initialize the new row
|
||||
do 570 l=1,iband4
|
||||
h(l) = 0.
|
||||
570 continue
|
||||
c fill in the non-zero elements of the row. jrot records the column
|
||||
c number of the first non-zero element in the row.
|
||||
j1 = 1
|
||||
do 580 l=1,kx2
|
||||
h(j1) = bx(ii,l)*pinv
|
||||
j1 = j1+nk1y
|
||||
580 continue
|
||||
zi = 0.
|
||||
jrot = (i-kx2)*nk1y+j
|
||||
c rotate the new row into triangle by givens transformations .
|
||||
do 620 irot=jrot,ncof
|
||||
piv = h(1)
|
||||
i2 = min0(iband3,ncof-irot)
|
||||
if(piv.eq.0.) then
|
||||
if (i2.le.0) go to 630
|
||||
go to 600
|
||||
endif
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,q(irot,1),cos,sin)
|
||||
c apply that givens transformation to the right hand side.
|
||||
call fprota(cos,sin,zi,ff(irot))
|
||||
if(i2.eq.0) go to 630
|
||||
c apply that givens transformation to the left hand side.
|
||||
do 590 l=1,i2
|
||||
l1 = l+1
|
||||
call fprota(cos,sin,h(l1),q(irot,l1))
|
||||
590 continue
|
||||
600 do 610 l=1,i2
|
||||
h(l) = h(l+1)
|
||||
610 continue
|
||||
h(i2+1) = 0.
|
||||
620 continue
|
||||
630 continue
|
||||
c find dmax, the maximum value for the diagonal elements in the
|
||||
c reduced triangle.
|
||||
640 dmax = 0.
|
||||
do 650 i=1,ncof
|
||||
if(q(i,1).le.dmax) go to 650
|
||||
dmax = q(i,1)
|
||||
650 continue
|
||||
c check whether the matrix is rank deficient.
|
||||
sigma = eps*dmax
|
||||
do 660 i=1,ncof
|
||||
if(q(i,1).le.sigma) go to 670
|
||||
660 continue
|
||||
c backward substitution in case of full rank.
|
||||
call fpback(q,ff,ncof,iband4,c,nc)
|
||||
rank = ncof
|
||||
go to 675
|
||||
c in case of rank deficiency, find the minimum norm solution.
|
||||
670 lwest = ncof*iband4+ncof+iband4
|
||||
if(lwrk.lt.lwest) go to 780
|
||||
lf = 1
|
||||
lh = lf+ncof
|
||||
la = lh+iband4
|
||||
call fprank(q,ff,ncof,iband4,nc,sigma,c,sq,rank,wrk(la),
|
||||
* wrk(lf),wrk(lh))
|
||||
675 do 680 i=1,ncof
|
||||
q(i,1) = q(i,1)/dmax
|
||||
680 continue
|
||||
c compute f(p).
|
||||
fp = 0.
|
||||
do 720 num = 1,nreg
|
||||
num1 = num-1
|
||||
lx = num1/nyy
|
||||
ly = num1-lx*nyy
|
||||
jrot = lx*nk1y+ly
|
||||
in = index(num)
|
||||
690 if(in.eq.0) go to 720
|
||||
store = 0.
|
||||
i1 = jrot
|
||||
do 710 i=1,kx1
|
||||
hxi = spx(in,i)
|
||||
j1 = i1
|
||||
do 700 j=1,ky1
|
||||
j1 = j1+1
|
||||
store = store+hxi*spy(in,j)*c(j1)
|
||||
700 continue
|
||||
i1 = i1+nk1y
|
||||
710 continue
|
||||
fp = fp+(w(in)*(z(in)-store))**2
|
||||
in = nummer(in)
|
||||
go to 690
|
||||
720 continue
|
||||
c test whether the approximation sp(x,y) is an acceptable solution.
|
||||
fpms = fp-s
|
||||
if(abs(fpms).le.acc) go to 820
|
||||
c test whether the maximum allowable number of iterations has been
|
||||
c reached.
|
||||
if(iter.eq.maxit) go to 795
|
||||
c carry out one more step of the iteration process.
|
||||
p2 = p
|
||||
f2 = fpms
|
||||
if(ich3.ne.0) go to 740
|
||||
if((f2-f3).gt.acc) go to 730
|
||||
c our initial choice of p is too large.
|
||||
p3 = p2
|
||||
f3 = f2
|
||||
p = p*con4
|
||||
if(p.le.p1) p = p1*con9 + p2*con1
|
||||
go to 770
|
||||
730 if(f2.lt.0.) ich3 = 1
|
||||
740 if(ich1.ne.0) go to 760
|
||||
if((f1-f2).gt.acc) go to 750
|
||||
c our initial choice of p is too small
|
||||
p1 = p2
|
||||
f1 = f2
|
||||
p = p/con4
|
||||
if(p3.lt.0.) go to 770
|
||||
if(p.ge.p3) p = p2*con1 + p3*con9
|
||||
go to 770
|
||||
750 if(f2.gt.0.) ich1 = 1
|
||||
c test whether the iteration process proceeds as theoretically
|
||||
c expected.
|
||||
760 if(f2.ge.f1 .or. f2.le.f3) go to 800
|
||||
c find the new value of p.
|
||||
p = fprati(p1,f1,p2,f2,p3,f3)
|
||||
770 continue
|
||||
c error codes and messages.
|
||||
780 ier = lwest
|
||||
go to 830
|
||||
785 ier = 5
|
||||
go to 830
|
||||
790 ier = 4
|
||||
go to 830
|
||||
795 ier = 3
|
||||
go to 830
|
||||
800 ier = 2
|
||||
go to 830
|
||||
810 ier = 1
|
||||
go to 830
|
||||
815 ier = -1
|
||||
fp = 0.
|
||||
820 if(ncof.ne.rank) ier = -rank
|
||||
c test whether x and y are in the original order.
|
||||
830 if(ichang.lt.0) go to 930
|
||||
c if not, interchange x and y once more.
|
||||
l1 = 1
|
||||
do 840 i=1,nk1x
|
||||
l2 = i
|
||||
do 840 j=1,nk1y
|
||||
f(l2) = c(l1)
|
||||
l1 = l1+1
|
||||
l2 = l2+nk1x
|
||||
840 continue
|
||||
do 850 i=1,ncof
|
||||
c(i) = f(i)
|
||||
850 continue
|
||||
do 860 i=1,m
|
||||
store = x(i)
|
||||
x(i) = y(i)
|
||||
y(i) = store
|
||||
860 continue
|
||||
n = min0(nx,ny)
|
||||
do 870 i=1,n
|
||||
store = tx(i)
|
||||
tx(i) = ty(i)
|
||||
ty(i) = store
|
||||
870 continue
|
||||
n1 = n+1
|
||||
if (nx.lt.ny) go to 880
|
||||
if (nx.eq.ny) go to 920
|
||||
go to 900
|
||||
880 do 890 i=n1,ny
|
||||
tx(i) = ty(i)
|
||||
890 continue
|
||||
go to 920
|
||||
900 do 910 i=n1,nx
|
||||
ty(i) = tx(i)
|
||||
910 continue
|
||||
920 l = nx
|
||||
nx = ny
|
||||
ny = l
|
||||
930 if(iopt.lt.0) go to 940
|
||||
nx0 = nx
|
||||
ny0 = ny
|
||||
940 return
|
||||
end
|
||||
|
||||
57
cxx/fitpack/fpsysy.f
Normal file
57
cxx/fitpack/fpsysy.f
Normal file
@ -0,0 +1,57 @@
|
||||
recursive subroutine fpsysy(a,n,g)
|
||||
implicit none
|
||||
c subroutine fpsysy solves a linear n x n symmetric system
|
||||
c (a) * (b) = (g)
|
||||
c on input, vector g contains the right hand side ; on output it will
|
||||
c contain the solution (b).
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer n
|
||||
c ..array arguments..
|
||||
real*8 a(6,6),g(6)
|
||||
c ..local scalars..
|
||||
real*8 fac
|
||||
integer i,i1,j,k
|
||||
c ..
|
||||
g(1) = g(1)/a(1,1)
|
||||
if(n.eq.1) return
|
||||
c decomposition of the symmetric matrix (a) = (l) * (d) *(l)'
|
||||
c with (l) a unit lower triangular matrix and (d) a diagonal
|
||||
c matrix
|
||||
do 10 k=2,n
|
||||
a(k,1) = a(k,1)/a(1,1)
|
||||
10 continue
|
||||
do 40 i=2,n
|
||||
i1 = i-1
|
||||
do 30 k=i,n
|
||||
fac = a(k,i)
|
||||
do 20 j=1,i1
|
||||
fac = fac-a(j,j)*a(k,j)*a(i,j)
|
||||
20 continue
|
||||
a(k,i) = fac
|
||||
if(k.gt.i) a(k,i) = fac/a(i,i)
|
||||
30 continue
|
||||
40 continue
|
||||
c solve the system (l)*(d)*(l)'*(b) = (g).
|
||||
c first step : solve (l)*(d)*(c) = (g).
|
||||
do 60 i=2,n
|
||||
i1 = i-1
|
||||
fac = g(i)
|
||||
do 50 j=1,i1
|
||||
fac = fac-g(j)*a(j,j)*a(i,j)
|
||||
50 continue
|
||||
g(i) = fac/a(i,i)
|
||||
60 continue
|
||||
c second step : solve (l)'*(b) = (c)
|
||||
i = n
|
||||
do 80 j=2,n
|
||||
i1 = i
|
||||
i = i-1
|
||||
fac = g(i)
|
||||
do 70 k=i1,n
|
||||
fac = fac-g(k)*a(k,i)
|
||||
70 continue
|
||||
g(i) = fac
|
||||
80 continue
|
||||
return
|
||||
end
|
||||
107
cxx/fitpack/fptrnp.f
Normal file
107
cxx/fitpack/fptrnp.f
Normal file
@ -0,0 +1,107 @@
|
||||
recursive subroutine fptrnp(m,mm,idim,n,nr,sp,p,b,z,a,q,right)
|
||||
implicit none
|
||||
c subroutine fptrnp reduces the (m+n-7) x (n-4) matrix a to upper
|
||||
c triangular form and applies the same givens transformations to
|
||||
c the (m) x (mm) x (idim) matrix z to obtain the (n-4) x (mm) x
|
||||
c (idim) matrix q
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 p
|
||||
integer m,mm,idim,n
|
||||
c ..array arguments..
|
||||
real*8 sp(m,4),b(n,5),z(m*mm*idim),a(n,5),q((n-4)*mm*idim),
|
||||
* right(mm*idim)
|
||||
integer nr(m)
|
||||
c ..local scalars..
|
||||
real*8 cos,pinv,piv,sin,one
|
||||
integer i,iband,irot,it,ii,i2,i3,j,jj,l,mid,nmd,m2,m3,
|
||||
* nrold,n4,number,n1
|
||||
c ..local arrays..
|
||||
real*8 h(7)
|
||||
c ..subroutine references..
|
||||
c fpgivs,fprota
|
||||
c ..
|
||||
one = 1
|
||||
if(p.gt.0.) pinv = one/p
|
||||
n4 = n-4
|
||||
mid = mm*idim
|
||||
m2 = m*mm
|
||||
m3 = n4*mm
|
||||
c reduce the matrix (a) to upper triangular form (r) using givens
|
||||
c rotations. apply the same transformations to the rows of matrix z
|
||||
c to obtain the mm x (n-4) matrix g.
|
||||
c store matrix (r) into (a) and g into q.
|
||||
c initialization.
|
||||
nmd = n4*mid
|
||||
do 50 i=1,nmd
|
||||
q(i) = 0.
|
||||
50 continue
|
||||
do 100 i=1,n4
|
||||
do 100 j=1,5
|
||||
a(i,j) = 0.
|
||||
100 continue
|
||||
nrold = 0
|
||||
c iband denotes the bandwidth of the matrices (a) and (r).
|
||||
iband = 4
|
||||
do 750 it=1,m
|
||||
number = nr(it)
|
||||
150 if(nrold.eq.number) go to 300
|
||||
if(p.le.0.) go to 700
|
||||
iband = 5
|
||||
c fetch a new row of matrix (b).
|
||||
n1 = nrold+1
|
||||
do 200 j=1,5
|
||||
h(j) = b(n1,j)*pinv
|
||||
200 continue
|
||||
c find the appropriate column of q.
|
||||
do 250 j=1,mid
|
||||
right(j) = 0.
|
||||
250 continue
|
||||
irot = nrold
|
||||
go to 450
|
||||
c fetch a new row of matrix (sp).
|
||||
300 h(iband) = 0.
|
||||
do 350 j=1,4
|
||||
h(j) = sp(it,j)
|
||||
350 continue
|
||||
c find the appropriate column of q.
|
||||
j = 0
|
||||
do 400 ii=1,idim
|
||||
l = (ii-1)*m2+(it-1)*mm
|
||||
do 400 jj=1,mm
|
||||
j = j+1
|
||||
l = l+1
|
||||
right(j) = z(l)
|
||||
400 continue
|
||||
irot = number
|
||||
c rotate the new row of matrix (a) into triangle.
|
||||
450 do 600 i=1,iband
|
||||
irot = irot+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 600
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a(irot,1),cos,sin)
|
||||
c apply that transformation to the rows of matrix q.
|
||||
j = 0
|
||||
do 500 ii=1,idim
|
||||
l = (ii-1)*m3+irot
|
||||
do 500 jj=1,mm
|
||||
j = j+1
|
||||
call fprota(cos,sin,right(j),q(l))
|
||||
l = l+n4
|
||||
500 continue
|
||||
c apply that transformation to the columns of (a).
|
||||
if(i.eq.iband) go to 650
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 550 j=i3,iband
|
||||
i2 = i2+1
|
||||
call fprota(cos,sin,h(j),a(irot,i2))
|
||||
550 continue
|
||||
600 continue
|
||||
650 if(nrold.eq.number) go to 750
|
||||
700 nrold = nrold+1
|
||||
go to 150
|
||||
750 continue
|
||||
return
|
||||
end
|
||||
214
cxx/fitpack/fptrpe.f
Normal file
214
cxx/fitpack/fptrpe.f
Normal file
@ -0,0 +1,214 @@
|
||||
recursive subroutine fptrpe(m,mm,idim,n,nr,sp,p,b,z,a,aa,q,right)
|
||||
implicit none
|
||||
c subroutine fptrpe reduces the (m+n-7) x (n-7) cyclic bandmatrix a
|
||||
c to upper triangular form and applies the same givens transformations
|
||||
c to the (m) x (mm) x (idim) matrix z to obtain the (n-7) x (mm) x
|
||||
c (idim) matrix q.
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 p
|
||||
integer m,mm,idim,n
|
||||
c ..array arguments..
|
||||
real*8 sp(m,4),b(n,5),z(m*mm*idim),a(n,5),aa(n,4),q((n-7)*mm*idim)
|
||||
*,
|
||||
* right(mm*idim)
|
||||
integer nr(m)
|
||||
c ..local scalars..
|
||||
real*8 co,pinv,piv,si,one
|
||||
integer i,irot,it,ii,i2,i3,j,jj,l,mid,nmd,m2,m3,
|
||||
* nrold,n4,number,n1,n7,n11,m1
|
||||
integer i1, ij,j1,jk,jper,l0,l1, ik
|
||||
c ..local arrays..
|
||||
real*8 h(5),h1(5),h2(4)
|
||||
c ..subroutine references..
|
||||
c fpgivs,fprota
|
||||
c ..
|
||||
one = 1
|
||||
if(p.gt.0.) pinv = one/p
|
||||
n4 = n-4
|
||||
n7 = n-7
|
||||
n11 = n-11
|
||||
mid = mm*idim
|
||||
m2 = m*mm
|
||||
m3 = n7*mm
|
||||
m1 = m-1
|
||||
c we determine the matrix (a) and then we reduce her to
|
||||
c upper triangular form (r) using givens rotations.
|
||||
c we apply the same transformations to the rows of matrix
|
||||
c z to obtain the (mm) x (n-7) matrix g.
|
||||
c we store matrix (r) into a and aa, g into q.
|
||||
c the n7 x n7 upper triangular matrix (r) has the form
|
||||
c | a1 ' |
|
||||
c (r) = | ' a2 |
|
||||
c | 0 ' |
|
||||
c with (a2) a n7 x 4 matrix and (a1) a n11 x n11 upper
|
||||
c triangular matrix of bandwidth 5.
|
||||
c initialization.
|
||||
nmd = n7*mid
|
||||
do 50 i=1,nmd
|
||||
q(i) = 0.
|
||||
50 continue
|
||||
do 100 i=1,n4
|
||||
a(i,5) = 0.
|
||||
do 100 j=1,4
|
||||
a(i,j) = 0.
|
||||
aa(i,j) = 0.
|
||||
100 continue
|
||||
jper = 0
|
||||
nrold = 0
|
||||
do 760 it=1,m1
|
||||
number = nr(it)
|
||||
120 if(nrold.eq.number) go to 180
|
||||
if(p.le.0.) go to 740
|
||||
c fetch a new row of matrix (b).
|
||||
n1 = nrold+1
|
||||
do 140 j=1,5
|
||||
h(j) = b(n1,j)*pinv
|
||||
140 continue
|
||||
c find the appropriate row of q.
|
||||
do 160 j=1,mid
|
||||
right(j) = 0.
|
||||
160 continue
|
||||
go to 240
|
||||
c fetch a new row of matrix (sp)
|
||||
180 h(5) = 0.
|
||||
do 200 j=1,4
|
||||
h(j) = sp(it,j)
|
||||
200 continue
|
||||
c find the appropriate row of q.
|
||||
j = 0
|
||||
do 220 ii=1,idim
|
||||
l = (ii-1)*m2+(it-1)*mm
|
||||
do 220 jj=1,mm
|
||||
j = j+1
|
||||
l = l+1
|
||||
right(j) = z(l)
|
||||
220 continue
|
||||
c test whether there are non-zero values in the new row of (a)
|
||||
c corresponding to the b-splines n(j,*),j=n7+1,...,n4.
|
||||
240 if(nrold.lt.n11) go to 640
|
||||
if(jper.ne.0) go to 320
|
||||
c initialize the matrix (aa).
|
||||
jk = n11+1
|
||||
do 300 i=1,4
|
||||
ik = jk
|
||||
do 260 j=1,5
|
||||
if(ik.le.0) go to 280
|
||||
aa(ik,i) = a(ik,j)
|
||||
ik = ik-1
|
||||
260 continue
|
||||
280 jk = jk+1
|
||||
300 continue
|
||||
jper = 1
|
||||
c if one of the non-zero elements of the new row corresponds to one of
|
||||
c the b-splines n(j;*),j=n7+1,...,n4,we take account of the periodicity
|
||||
c conditions for setting up this row of (a).
|
||||
320 do 340 i=1,4
|
||||
h1(i) = 0.
|
||||
h2(i) = 0.
|
||||
340 continue
|
||||
h1(5) = 0.
|
||||
j = nrold-n11
|
||||
do 420 i=1,5
|
||||
j = j+1
|
||||
l0 = j
|
||||
360 l1 = l0-4
|
||||
if(l1.le.0) go to 400
|
||||
if(l1.le.n11) go to 380
|
||||
l0 = l1-n11
|
||||
go to 360
|
||||
380 h1(l1) = h(i)
|
||||
go to 420
|
||||
400 h2(l0) = h2(l0) + h(i)
|
||||
420 continue
|
||||
c rotate the new row of (a) into triangle.
|
||||
if(n11.le.0) go to 560
|
||||
c rotations with the rows 1,2,...,n11 of (a).
|
||||
do 540 irot=1,n11
|
||||
piv = h1(1)
|
||||
i2 = min0(n11-irot,4)
|
||||
if(piv.eq.0.) go to 500
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a(irot,1),co,si)
|
||||
c apply that transformation to the columns of matrix q.
|
||||
j = 0
|
||||
do 440 ii=1,idim
|
||||
l = (ii-1)*m3+irot
|
||||
do 440 jj=1,mm
|
||||
j = j+1
|
||||
call fprota(co,si,right(j),q(l))
|
||||
l = l+n7
|
||||
440 continue
|
||||
c apply that transformation to the rows of (a) with respect to aa.
|
||||
do 460 i=1,4
|
||||
call fprota(co,si,h2(i),aa(irot,i))
|
||||
460 continue
|
||||
c apply that transformation to the rows of (a) with respect to a.
|
||||
if(i2.eq.0) go to 560
|
||||
do 480 i=1,i2
|
||||
i1 = i+1
|
||||
call fprota(co,si,h1(i1),a(irot,i1))
|
||||
480 continue
|
||||
500 do 520 i=1,i2
|
||||
h1(i) = h1(i+1)
|
||||
520 continue
|
||||
h1(i2+1) = 0.
|
||||
540 continue
|
||||
c rotations with the rows n11+1,...,n7 of a.
|
||||
560 do 620 irot=1,4
|
||||
ij = n11+irot
|
||||
if(ij.le.0) go to 620
|
||||
piv = h2(irot)
|
||||
if(piv.eq.0.) go to 620
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,aa(ij,irot),co,si)
|
||||
c apply that transformation to the columns of matrix q.
|
||||
j = 0
|
||||
do 580 ii=1,idim
|
||||
l = (ii-1)*m3+ij
|
||||
do 580 jj=1,mm
|
||||
j = j+1
|
||||
call fprota(co,si,right(j),q(l))
|
||||
l = l+n7
|
||||
580 continue
|
||||
if(irot.eq.4) go to 620
|
||||
c apply that transformation to the rows of (a) with respect to aa.
|
||||
j1 = irot+1
|
||||
do 600 i=j1,4
|
||||
call fprota(co,si,h2(i),aa(ij,i))
|
||||
600 continue
|
||||
620 continue
|
||||
go to 720
|
||||
c rotation into triangle of the new row of (a), in case the elements
|
||||
c corresponding to the b-splines n(j;*),j=n7+1,...,n4 are all zero.
|
||||
640 irot =nrold
|
||||
do 700 i=1,5
|
||||
irot = irot+1
|
||||
piv = h(i)
|
||||
if(piv.eq.0.) go to 700
|
||||
c calculate the parameters of the givens transformation.
|
||||
call fpgivs(piv,a(irot,1),co,si)
|
||||
c apply that transformation to the columns of matrix g.
|
||||
j = 0
|
||||
do 660 ii=1,idim
|
||||
l = (ii-1)*m3+irot
|
||||
do 660 jj=1,mm
|
||||
j = j+1
|
||||
call fprota(co,si,right(j),q(l))
|
||||
l = l+n7
|
||||
660 continue
|
||||
c apply that transformation to the rows of (a).
|
||||
if(i.eq.5) go to 700
|
||||
i2 = 1
|
||||
i3 = i+1
|
||||
do 680 j=i3,5
|
||||
i2 = i2+1
|
||||
call fprota(co,si,h(j),a(irot,i2))
|
||||
680 continue
|
||||
700 continue
|
||||
720 if(nrold.eq.number) go to 760
|
||||
740 nrold = nrold+1
|
||||
go to 120
|
||||
760 continue
|
||||
return
|
||||
end
|
||||
103
cxx/fitpack/insert.f
Normal file
103
cxx/fitpack/insert.f
Normal file
@ -0,0 +1,103 @@
|
||||
recursive subroutine insert(iopt,t,n,c,k,x,tt,nn,cc,nest,ier)
|
||||
implicit none
|
||||
c subroutine insert inserts a new knot x into a spline function s(x)
|
||||
c of degree k and calculates the b-spline representation of s(x) with
|
||||
c respect to the new set of knots. in addition, if iopt.ne.0, s(x)
|
||||
c will be considered as a periodic spline with period per=t(n-k)-t(k+1)
|
||||
c satisfying the boundary constraints
|
||||
c t(i+n-2*k-1) = t(i)+per ,i=1,2,...,2*k+1
|
||||
c c(i+n-2*k-1) = c(i) ,i=1,2,...,k
|
||||
c in that case, the knots and b-spline coefficients returned will also
|
||||
c satisfy these boundary constraints, i.e.
|
||||
c tt(i+nn-2*k-1) = tt(i)+per ,i=1,2,...,2*k+1
|
||||
c cc(i+nn-2*k-1) = cc(i) ,i=1,2,...,k
|
||||
c
|
||||
c calling sequence:
|
||||
c call insert(iopt,t,n,c,k,x,tt,nn,cc,nest,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c iopt : integer flag, specifying whether (iopt.ne.0) or not (iopt=0)
|
||||
c the given spline must be considered as being periodic.
|
||||
c t : array,length nest, which contains the position of the knots.
|
||||
c n : integer, giving the total number of knots of s(x).
|
||||
c c : array,length nest, which contains the b-spline coefficients.
|
||||
c k : integer, giving the degree of s(x).
|
||||
c x : real, which gives the location of the knot to be inserted.
|
||||
c nest : integer specifying the dimension of the arrays t,c,tt and cc
|
||||
c nest > n.
|
||||
c
|
||||
c output parameters:
|
||||
c tt : array,length nest, which contains the position of the knots
|
||||
c after insertion.
|
||||
c nn : integer, giving the total number of knots after insertion
|
||||
c cc : array,length nest, which contains the b-spline coefficients
|
||||
c of s(x) with respect to the new set of knots.
|
||||
c ier : error flag
|
||||
c ier = 0 : normal return
|
||||
c ier =10 : invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c nest > n
|
||||
c t(k+1) <= x <= t(n-k)
|
||||
c in case of a periodic spline (iopt.ne.0) there must be
|
||||
c either at least k interior knots t(j) satisfying t(k+1)<t(j)<=x
|
||||
c or at least k interior knots t(j) satisfying x<=t(j)<t(n-k)
|
||||
c
|
||||
c other subroutines required: fpinst.
|
||||
c
|
||||
c further comments:
|
||||
c subroutine insert may be called as follows
|
||||
c call insert(iopt,t,n,c,k,x,t,n,c,nest,ier)
|
||||
c in which case the new representation will simply replace the old one
|
||||
c
|
||||
c references :
|
||||
c boehm w : inserting new knots into b-spline curves. computer aided
|
||||
c design 12 (1980) 199-201.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : february 2007 (second interval search added)
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer iopt,n,k,nn,nest,ier
|
||||
real*8 x
|
||||
c ..array arguments..
|
||||
real*8 t(nest),c(nest),tt(nest),cc(nest)
|
||||
c ..local scalars..
|
||||
integer kk,k1,l,nk
|
||||
c ..
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(nest.le.n) go to 40
|
||||
k1 = k+1
|
||||
nk = n-k
|
||||
if(x.lt.t(k1) .or. x.gt.t(nk)) go to 40
|
||||
c search for knot interval t(l) <= x < t(l+1).
|
||||
l = k1
|
||||
10 if(x.lt.t(l+1)) go to 20
|
||||
l = l+1
|
||||
if(l.eq.nk) go to 14
|
||||
go to 10
|
||||
c if no interval found above, then reverse the search and
|
||||
c look for knot interval t(l) < x <= t(l+1).
|
||||
14 l = nk-1
|
||||
16 if(x.gt.t(l)) go to 20
|
||||
l = l-1
|
||||
if(l.eq.k) go to 40
|
||||
go to 16
|
||||
20 if(t(l).ge.t(l+1)) go to 40
|
||||
if(iopt.eq.0) go to 30
|
||||
kk = 2*k
|
||||
if(l.le.kk .and. l.ge.(n-kk)) go to 40
|
||||
30 ier = 0
|
||||
c insert the new knot.
|
||||
call fpinst(iopt,t,n,c,k,x,l,tt,nn,cc,nest)
|
||||
40 return
|
||||
end
|
||||
335
cxx/fitpack/parcur.f
Normal file
335
cxx/fitpack/parcur.f
Normal file
@ -0,0 +1,335 @@
|
||||
recursive subroutine parcur(iopt,ipar,idim,m,u,mx,x,w,ub,ue,k,s,
|
||||
* nest,n,t,nc,c,fp,wrk,lwrk,iwrk,ier)
|
||||
implicit none
|
||||
c given the ordered set of m points x(i) in the idim-dimensional space
|
||||
c and given also a corresponding set of strictly increasing values u(i)
|
||||
c and the set of positive numbers w(i),i=1,2,...,m, subroutine parcur
|
||||
c determines a smooth approximating spline curve s(u), i.e.
|
||||
c x1 = s1(u)
|
||||
c x2 = s2(u) ub <= u <= ue
|
||||
c .........
|
||||
c xidim = sidim(u)
|
||||
c with sj(u),j=1,2,...,idim spline functions of degree k with common
|
||||
c knots t(j),j=1,2,...,n.
|
||||
c if ipar=1 the values ub,ue and u(i),i=1,2,...,m must be supplied by
|
||||
c the user. if ipar=0 these values are chosen automatically by parcur
|
||||
c as v(1) = 0
|
||||
c v(i) = v(i-1) + dist(x(i),x(i-1)) ,i=2,3,...,m
|
||||
c u(i) = v(i)/v(m) ,i=1,2,...,m
|
||||
c ub = u(1) = 0, ue = u(m) = 1.
|
||||
c if iopt=-1 parcur calculates the weighted least-squares spline curve
|
||||
c according to a given set of knots.
|
||||
c if iopt>=0 the number of knots of the splines sj(u) and the position
|
||||
c t(j),j=1,2,...,n is chosen automatically by the routine. the smooth-
|
||||
c ness of s(u) is then achieved by minimalizing the discontinuity
|
||||
c jumps of the k-th derivative of s(u) at the knots t(j),j=k+2,k+3,...,
|
||||
c n-k-1. the amount of smoothness is determined by the condition that
|
||||
c f(p)=sum((w(i)*dist(x(i),s(u(i))))**2) be <= s, with s a given non-
|
||||
c negative constant, called the smoothing factor.
|
||||
c the fit s(u) is given in the b-spline representation and can be
|
||||
c evaluated by means of subroutine curev.
|
||||
c
|
||||
c calling sequence:
|
||||
c call parcur(iopt,ipar,idim,m,u,mx,x,w,ub,ue,k,s,nest,n,t,nc,c,
|
||||
c * fp,wrk,lwrk,iwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt : integer flag. on entry iopt must specify whether a weighted
|
||||
c least-squares spline curve (iopt=-1) or a smoothing spline
|
||||
c curve (iopt=0 or 1) must be determined.if iopt=0 the routine
|
||||
c will start with an initial set of knots t(i)=ub,t(i+k+1)=ue,
|
||||
c i=1,2,...,k+1. if iopt=1 the routine will continue with the
|
||||
c knots found at the last call of the routine.
|
||||
c attention: a call with iopt=1 must always be immediately
|
||||
c preceded by another call with iopt=1 or iopt=0.
|
||||
c unchanged on exit.
|
||||
c ipar : integer flag. on entry ipar must specify whether (ipar=1)
|
||||
c the user will supply the parameter values u(i),ub and ue
|
||||
c or whether (ipar=0) these values are to be calculated by
|
||||
c parcur. unchanged on exit.
|
||||
c idim : integer. on entry idim must specify the dimension of the
|
||||
c curve. 0 < idim < 11.
|
||||
c unchanged on exit.
|
||||
c m : integer. on entry m must specify the number of data points.
|
||||
c m > k. unchanged on exit.
|
||||
c u : real array of dimension at least (m). in case ipar=1,before
|
||||
c entry, u(i) must be set to the i-th value of the parameter
|
||||
c variable u for i=1,2,...,m. these values must then be
|
||||
c supplied in strictly ascending order and will be unchanged
|
||||
c on exit. in case ipar=0, on exit,array u will contain the
|
||||
c values u(i) as determined by parcur.
|
||||
c mx : integer. on entry mx must specify the actual dimension of
|
||||
c the array x as declared in the calling (sub)program. mx must
|
||||
c not be too small (see x). unchanged on exit.
|
||||
c x : real array of dimension at least idim*m.
|
||||
c before entry, x(idim*(i-1)+j) must contain the j-th coord-
|
||||
c inate of the i-th data point for i=1,2,...,m and j=1,2,...,
|
||||
c idim. unchanged on exit.
|
||||
c w : real array of dimension at least (m). before entry, w(i)
|
||||
c must be set to the i-th value in the set of weights. the
|
||||
c w(i) must be strictly positive. unchanged on exit.
|
||||
c see also further comments.
|
||||
c ub,ue : real values. on entry (in case ipar=1) ub and ue must
|
||||
c contain the lower and upper bound for the parameter u.
|
||||
c ub <=u(1), ue>= u(m). if ipar = 0 these values will
|
||||
c automatically be set to 0 and 1 by parcur.
|
||||
c k : integer. on entry k must specify the degree of the splines.
|
||||
c 1<=k<=5. it is recommended to use cubic splines (k=3).
|
||||
c the user is strongly dissuaded from choosing k even,together
|
||||
c with a small s-value. unchanged on exit.
|
||||
c s : real.on entry (in case iopt>=0) s must specify the smoothing
|
||||
c factor. s >=0. unchanged on exit.
|
||||
c for advice on the choice of s see further comments.
|
||||
c nest : integer. on entry nest must contain an over-estimate of the
|
||||
c total number of knots of the splines returned, to indicate
|
||||
c the storage space available to the routine. nest >=2*k+2.
|
||||
c in most practical situation nest=m/2 will be sufficient.
|
||||
c always large enough is nest=m+k+1, the number of knots
|
||||
c needed for interpolation (s=0). unchanged on exit.
|
||||
c n : integer.
|
||||
c unless ier = 10 (in case iopt >=0), n will contain the
|
||||
c total number of knots of the smoothing spline curve returned
|
||||
c if the computation mode iopt=1 is used this value of n
|
||||
c should be left unchanged between subsequent calls.
|
||||
c in case iopt=-1, the value of n must be specified on entry.
|
||||
c t : real array of dimension at least (nest).
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline curve,i.e. the position of the interior knots t(k+2),
|
||||
c t(k+3),..,t(n-k-1) as well as the position of the additional
|
||||
c t(1)=t(2)=...=t(k+1)=ub and t(n-k)=...=t(n)=ue needed for
|
||||
c the b-spline representation.
|
||||
c if the computation mode iopt=1 is used, the values of t(1),
|
||||
c t(2),...,t(n) should be left unchanged between subsequent
|
||||
c calls. if the computation mode iopt=-1 is used, the values
|
||||
c t(k+2),...,t(n-k-1) must be supplied by the user, before
|
||||
c entry. see also the restrictions (ier=10).
|
||||
c nc : integer. on entry nc must specify the actual dimension of
|
||||
c the array c as declared in the calling (sub)program. nc
|
||||
c must not be too small (see c). unchanged on exit.
|
||||
c c : real array of dimension at least (nest*idim).
|
||||
c on successful exit, this array will contain the coefficients
|
||||
c in the b-spline representation of the spline curve s(u),i.e.
|
||||
c the b-spline coefficients of the spline sj(u) will be given
|
||||
c in c(n*(j-1)+i),i=1,2,...,n-k-1 for j=1,2,...,idim.
|
||||
c fp : real. unless ier = 10, fp contains the weighted sum of
|
||||
c squared residuals of the spline curve returned.
|
||||
c wrk : real array of dimension at least m*(k+1)+nest*(6+idim+3*k).
|
||||
c used as working space. if the computation mode iopt=1 is
|
||||
c used, the values wrk(1),...,wrk(n) should be left unchanged
|
||||
c between subsequent calls.
|
||||
c lwrk : integer. on entry,lwrk must specify the actual dimension of
|
||||
c the array wrk as declared in the calling (sub)program. lwrk
|
||||
c must not be too small (see wrk). unchanged on exit.
|
||||
c iwrk : integer array of dimension at least (nest).
|
||||
c used as working space. if the computation mode iopt=1 is
|
||||
c used,the values iwrk(1),...,iwrk(n) should be left unchanged
|
||||
c between subsequent calls.
|
||||
c ier : integer. unless the routine detects an error, ier contains a
|
||||
c non-positive value on exit, i.e.
|
||||
c ier=0 : normal return. the curve returned has a residual sum of
|
||||
c squares fp such that abs(fp-s)/s <= tol with tol a relat-
|
||||
c ive tolerance set to 0.001 by the program.
|
||||
c ier=-1 : normal return. the curve returned is an interpolating
|
||||
c spline curve (fp=0).
|
||||
c ier=-2 : normal return. the curve returned is the weighted least-
|
||||
c squares polynomial curve of degree k.in this extreme case
|
||||
c fp gives the upper bound fp0 for the smoothing factor s.
|
||||
c ier=1 : error. the required storage space exceeds the available
|
||||
c storage space, as specified by the parameter nest.
|
||||
c probably causes : nest too small. if nest is already
|
||||
c large (say nest > m/2), it may also indicate that s is
|
||||
c too small
|
||||
c the approximation returned is the least-squares spline
|
||||
c curve according to the knots t(1),t(2),...,t(n). (n=nest)
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=2 : error. a theoretically impossible result was found during
|
||||
c the iteration process for finding a smoothing spline curve
|
||||
c with fp = s. probably causes : s too small.
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=3 : error. the maximal number of iterations maxit (set to 20
|
||||
c by the program) allowed for finding a smoothing curve
|
||||
c with fp=s has been reached. probably causes : s too small
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=10 : error. on entry, the input data are controlled on validity
|
||||
c the following restrictions must be satisfied.
|
||||
c -1<=iopt<=1, 1<=k<=5, m>k, nest>2*k+2, w(i)>0,i=1,2,...,m
|
||||
c 0<=ipar<=1, 0<idim<=10, lwrk>=(k+1)*m+nest*(6+idim+3*k),
|
||||
c nc>=nest*idim
|
||||
c if ipar=0: sum j=1,idim (x(idim*i+j)-x(idim*(i-1)+j))**2>0
|
||||
c i=1,2,...,m-1.
|
||||
c if ipar=1: ub<=u(1)<u(2)<...<u(m)<=ue
|
||||
c if iopt=-1: 2*k+2<=n<=min(nest,m+k+1)
|
||||
c ub<t(k+2)<t(k+3)<...<t(n-k-1)<ue
|
||||
c (ub=0 and ue=1 in case ipar=0)
|
||||
c the schoenberg-whitney conditions, i.e. there
|
||||
c must be a subset of data points uu(j) such that
|
||||
c t(j) < uu(j) < t(j+k+1), j=1,2,...,n-k-1
|
||||
c if iopt>=0: s>=0
|
||||
c if s=0 : nest >= m+k+1
|
||||
c if one of these conditions is found to be violated,control
|
||||
c is immediately repassed to the calling program. in that
|
||||
c case there is no approximation returned.
|
||||
c
|
||||
c further comments:
|
||||
c by means of the parameter s, the user can control the tradeoff
|
||||
c between closeness of fit and smoothness of fit of the approximation.
|
||||
c if s is too large, the curve will be too smooth and signal will be
|
||||
c lost ; if s is too small the curve will pick up too much noise. in
|
||||
c the extreme cases the program will return an interpolating curve if
|
||||
c s=0 and the least-squares polynomial curve of degree k if s is
|
||||
c very large. between these extremes, a properly chosen s will result
|
||||
c in a good compromise between closeness of fit and smoothness of fit.
|
||||
c to decide whether an approximation, corresponding to a certain s is
|
||||
c satisfactory the user is highly recommended to inspect the fits
|
||||
c graphically.
|
||||
c recommended values for s depend on the weights w(i). if these are
|
||||
c taken as 1/d(i) with d(i) an estimate of the standard deviation of
|
||||
c x(i), a good s-value should be found in the range (m-sqrt(2*m),m+
|
||||
c sqrt(2*m)). if nothing is known about the statistical error in x(i)
|
||||
c each w(i) can be set equal to one and s determined by trial and
|
||||
c error, taking account of the comments above. the best is then to
|
||||
c start with a very large value of s ( to determine the least-squares
|
||||
c polynomial curve and the upper bound fp0 for s) and then to
|
||||
c progressively decrease the value of s ( say by a factor 10 in the
|
||||
c beginning, i.e. s=fp0/10, fp0/100,...and more carefully as the
|
||||
c approximating curve shows more detail) to obtain closer fits.
|
||||
c to economize the search for a good s-value the program provides with
|
||||
c different modes of computation. at the first call of the routine, or
|
||||
c whenever he wants to restart with the initial set of knots the user
|
||||
c must set iopt=0.
|
||||
c if iopt=1 the program will continue with the set of knots found at
|
||||
c the last call of the routine. this will save a lot of computation
|
||||
c time if parcur is called repeatedly for different values of s.
|
||||
c the number of knots of the spline returned and their location will
|
||||
c depend on the value of s and on the complexity of the shape of the
|
||||
c curve underlying the data. but, if the computation mode iopt=1 is
|
||||
c used, the knots returned may also depend on the s-values at previous
|
||||
c calls (if these were smaller). therefore, if after a number of
|
||||
c trials with different s-values and iopt=1, the user can finally
|
||||
c accept a fit as satisfactory, it may be worthwhile for him to call
|
||||
c parcur once more with the selected value for s but now with iopt=0.
|
||||
c indeed, parcur may then return an approximation of the same quality
|
||||
c of fit but with fewer knots and therefore better if data reduction
|
||||
c is also an important objective for the user.
|
||||
c
|
||||
c the form of the approximating curve can strongly be affected by
|
||||
c the choice of the parameter values u(i). if there is no physical
|
||||
c reason for choosing a particular parameter u, often good results
|
||||
c will be obtained with the choice of parcur (in case ipar=0), i.e.
|
||||
c v(1)=0, v(i)=v(i-1)+q(i), i=2,...,m, u(i)=v(i)/v(m), i=1,..,m
|
||||
c where
|
||||
c q(i)= sqrt(sum j=1,idim (xj(i)-xj(i-1))**2 )
|
||||
c other possibilities for q(i) are
|
||||
c q(i)= sum j=1,idim (xj(i)-xj(i-1))**2
|
||||
c q(i)= sum j=1,idim abs(xj(i)-xj(i-1))
|
||||
c q(i)= max j=1,idim abs(xj(i)-xj(i-1))
|
||||
c q(i)= 1
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpback,fpbspl,fpchec,fppara,fpdisc,fpgivs,fpknot,fprati,fprota
|
||||
c
|
||||
c references:
|
||||
c dierckx p. : algorithms for smoothing data with periodic and
|
||||
c parametric splines, computer graphics and image
|
||||
c processing 20 (1982) 171-184.
|
||||
c dierckx p. : algorithms for smoothing data with periodic and param-
|
||||
c etric splines, report tw55, dept. computer science,
|
||||
c k.u.leuven, 1981.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u. leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : may 1979
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 ub,ue,s,fp
|
||||
integer iopt,ipar,idim,m,mx,k,nest,n,nc,lwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 u(m),x(mx),w(m),t(nest),c(nc),wrk(lwrk)
|
||||
integer iwrk(nest)
|
||||
c ..local scalars..
|
||||
real*8 tol,dist
|
||||
integer i,ia,ib,ifp,ig,iq,iz,i1,i2,j,k1,k2,lwest,maxit,nmin,ncc
|
||||
c ..function references
|
||||
real*8 sqrt
|
||||
c ..
|
||||
c we set up the parameters tol and maxit
|
||||
maxit = 20
|
||||
tol = 0.1e-02
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(iopt.lt.(-1) .or. iopt.gt.1) go to 90
|
||||
if(ipar.lt.0 .or. ipar.gt.1) go to 90
|
||||
if(idim.le.0 .or. idim.gt.10) go to 90
|
||||
if(k.le.0 .or. k.gt.5) go to 90
|
||||
k1 = k+1
|
||||
k2 = k1+1
|
||||
nmin = 2*k1
|
||||
if(m.lt.k1 .or. nest.lt.nmin) go to 90
|
||||
ncc = nest*idim
|
||||
if(mx.lt.m*idim .or. nc.lt.ncc) go to 90
|
||||
lwest = m*k1+nest*(6+idim+3*k)
|
||||
if(lwrk.lt.lwest) go to 90
|
||||
if(ipar.ne.0 .or. iopt.gt.0) go to 40
|
||||
i1 = 0
|
||||
i2 = idim
|
||||
u(1) = 0.
|
||||
do 20 i=2,m
|
||||
dist = 0.
|
||||
do 10 j=1,idim
|
||||
i1 = i1+1
|
||||
i2 = i2+1
|
||||
dist = dist+(x(i2)-x(i1))**2
|
||||
10 continue
|
||||
u(i) = u(i-1)+sqrt(dist)
|
||||
20 continue
|
||||
if(u(m).le.0.) go to 90
|
||||
do 30 i=2,m
|
||||
u(i) = u(i)/u(m)
|
||||
30 continue
|
||||
ub = 0.
|
||||
ue = 1.
|
||||
u(m) = ue
|
||||
40 if(ub.gt.u(1) .or. ue.lt.u(m) .or. w(1).le.0.) go to 90
|
||||
do 50 i=2,m
|
||||
if(u(i-1).ge.u(i) .or. w(i).le.0.) go to 90
|
||||
50 continue
|
||||
if(iopt.ge.0) go to 70
|
||||
if(n.lt.nmin .or. n.gt.nest) go to 90
|
||||
j = n
|
||||
do 60 i=1,k1
|
||||
t(i) = ub
|
||||
t(j) = ue
|
||||
j = j-1
|
||||
60 continue
|
||||
call fpchec(u,m,t,n,k,ier)
|
||||
if (ier.eq.0) go to 80
|
||||
go to 90
|
||||
70 if(s.lt.0.) go to 90
|
||||
if(s.eq.0. .and. nest.lt.(m+k1)) go to 90
|
||||
ier = 0
|
||||
c we partition the working space and determine the spline curve.
|
||||
80 ifp = 1
|
||||
iz = ifp+nest
|
||||
ia = iz+ncc
|
||||
ib = ia+nest*k1
|
||||
ig = ib+nest*k2
|
||||
iq = ig+nest*k2
|
||||
call fppara(iopt,idim,m,u,mx,x,w,ub,ue,k,s,nest,tol,maxit,k1,k2,
|
||||
* n,t,ncc,c,fp,wrk(ifp),wrk(iz),wrk(ia),wrk(ib),wrk(ig),wrk(iq),
|
||||
* iwrk,ier)
|
||||
90 return
|
||||
end
|
||||
180
cxx/fitpack/parder.f
Normal file
180
cxx/fitpack/parder.f
Normal file
@ -0,0 +1,180 @@
|
||||
recursive subroutine parder(tx,nx,ty,ny,c,kx,ky,nux,nuy,x,mx,
|
||||
* y,my,z,wrk,lwrk,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c subroutine parder evaluates on a grid (x(i),y(j)),i=1,...,mx; j=1,...
|
||||
c ,my the partial derivative ( order nux,nuy) of a bivariate spline
|
||||
c s(x,y) of degrees kx and ky, given in the b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c call parder(tx,nx,ty,ny,c,kx,ky,nux,nuy,x,mx,y,my,z,wrk,lwrk,
|
||||
c * iwrk,kwrk,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c tx : real array, length nx, which contains the position of the
|
||||
c knots in the x-direction.
|
||||
c nx : integer, giving the total number of knots in the x-direction
|
||||
c ty : real array, length ny, which contains the position of the
|
||||
c knots in the y-direction.
|
||||
c ny : integer, giving the total number of knots in the y-direction
|
||||
c c : real array, length (nx-kx-1)*(ny-ky-1), which contains the
|
||||
c b-spline coefficients.
|
||||
c kx,ky : integer values, giving the degrees of the spline.
|
||||
c nux : integer values, specifying the order of the partial
|
||||
c nuy derivative. 0<=nux<kx, 0<=nuy<ky.
|
||||
c x : real array of dimension (mx).
|
||||
c before entry x(i) must be set to the x co-ordinate of the
|
||||
c i-th grid point along the x-axis.
|
||||
c tx(kx+1)<=x(i-1)<=x(i)<=tx(nx-kx), i=2,...,mx.
|
||||
c mx : on entry mx must specify the number of grid points along
|
||||
c the x-axis. mx >=1.
|
||||
c y : real array of dimension (my).
|
||||
c before entry y(j) must be set to the y co-ordinate of the
|
||||
c j-th grid point along the y-axis.
|
||||
c ty(ky+1)<=y(j-1)<=y(j)<=ty(ny-ky), j=2,...,my.
|
||||
c my : on entry my must specify the number of grid points along
|
||||
c the y-axis. my >=1.
|
||||
c wrk : real array of dimension lwrk. used as workspace.
|
||||
c lwrk : integer, specifying the dimension of wrk.
|
||||
c lwrk >= mx*(kx+1-nux)+my*(ky+1-nuy)+(nx-kx-1)*(ny-ky-1)
|
||||
c iwrk : integer array of dimension kwrk. used as workspace.
|
||||
c kwrk : integer, specifying the dimension of iwrk. kwrk >= mx+my.
|
||||
c
|
||||
c output parameters:
|
||||
c z : real array of dimension (mx*my).
|
||||
c on successful exit z(my*(i-1)+j) contains the value of the
|
||||
c specified partial derivative of s(x,y) at the point
|
||||
c (x(i),y(j)),i=1,...,mx;j=1,...,my.
|
||||
c ier : integer error flag
|
||||
c ier=0 : normal return
|
||||
c ier=10: invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c mx >=1, my >=1, 0 <= nux < kx, 0 <= nuy < ky, kwrk>=mx+my
|
||||
c lwrk>=mx*(kx+1-nux)+my*(ky+1-nuy)+(nx-kx-1)*(ny-ky-1),
|
||||
c tx(kx+1) <= x(i-1) <= x(i) <= tx(nx-kx), i=2,...,mx
|
||||
c ty(ky+1) <= y(j-1) <= y(j) <= ty(ny-ky), j=2,...,my
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpbisp,fpbspl
|
||||
c
|
||||
c references :
|
||||
c de boor c : on calculating with b-splines, j. approximation theory
|
||||
c 6 (1972) 50-62.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1989
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer nx,ny,kx,ky,nux,nuy,mx,my,lwrk,kwrk,ier
|
||||
c ..array arguments..
|
||||
integer iwrk(kwrk)
|
||||
real*8 tx(nx),ty(ny),c((nx-kx-1)*(ny-ky-1)),x(mx),y(my),z(mx*my),
|
||||
* wrk(lwrk)
|
||||
c ..local scalars..
|
||||
integer i,iwx,iwy,j,kkx,kky,kx1,ky1,lx,ly,lwest,l1,l2,m,m0,m1,
|
||||
* nc,nkx1,nky1,nxx,nyy
|
||||
real*8 ak,fac
|
||||
c ..
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
kx1 = kx+1
|
||||
ky1 = ky+1
|
||||
nkx1 = nx-kx1
|
||||
nky1 = ny-ky1
|
||||
nc = nkx1*nky1
|
||||
if(nux.lt.0 .or. nux.ge.kx) go to 400
|
||||
if(nuy.lt.0 .or. nuy.ge.ky) go to 400
|
||||
lwest = nc +(kx1-nux)*mx+(ky1-nuy)*my
|
||||
if(lwrk.lt.lwest) go to 400
|
||||
if(kwrk.lt.(mx+my)) go to 400
|
||||
if (mx.lt.1) go to 400
|
||||
if (mx.eq.1) go to 30
|
||||
go to 10
|
||||
10 do 20 i=2,mx
|
||||
if(x(i).lt.x(i-1)) go to 400
|
||||
20 continue
|
||||
30 if (my.lt.1) go to 400
|
||||
if (my.eq.1) go to 60
|
||||
go to 40
|
||||
40 do 50 i=2,my
|
||||
if(y(i).lt.y(i-1)) go to 400
|
||||
50 continue
|
||||
60 ier = 0
|
||||
nxx = nkx1
|
||||
nyy = nky1
|
||||
kkx = kx
|
||||
kky = ky
|
||||
c the partial derivative of order (nux,nuy) of a bivariate spline of
|
||||
c degrees kx,ky is a bivariate spline of degrees kx-nux,ky-nuy.
|
||||
c we calculate the b-spline coefficients of this spline
|
||||
do 70 i=1,nc
|
||||
wrk(i) = c(i)
|
||||
70 continue
|
||||
if(nux.eq.0) go to 200
|
||||
lx = 1
|
||||
do 100 j=1,nux
|
||||
ak = kkx
|
||||
nxx = nxx-1
|
||||
l1 = lx
|
||||
m0 = 1
|
||||
do 90 i=1,nxx
|
||||
l1 = l1+1
|
||||
l2 = l1+kkx
|
||||
fac = tx(l2)-tx(l1)
|
||||
if(fac.le.0.) go to 90
|
||||
do 80 m=1,nyy
|
||||
m1 = m0+nyy
|
||||
wrk(m0) = (wrk(m1)-wrk(m0))*ak/fac
|
||||
m0 = m0+1
|
||||
80 continue
|
||||
90 continue
|
||||
lx = lx+1
|
||||
kkx = kkx-1
|
||||
100 continue
|
||||
200 if(nuy.eq.0) go to 300
|
||||
ly = 1
|
||||
do 230 j=1,nuy
|
||||
ak = kky
|
||||
nyy = nyy-1
|
||||
l1 = ly
|
||||
do 220 i=1,nyy
|
||||
l1 = l1+1
|
||||
l2 = l1+kky
|
||||
fac = ty(l2)-ty(l1)
|
||||
if(fac.le.0.) go to 220
|
||||
m0 = i
|
||||
do 210 m=1,nxx
|
||||
m1 = m0+1
|
||||
wrk(m0) = (wrk(m1)-wrk(m0))*ak/fac
|
||||
m0 = m0+nky1
|
||||
210 continue
|
||||
220 continue
|
||||
ly = ly+1
|
||||
kky = kky-1
|
||||
230 continue
|
||||
m0 = nyy
|
||||
m1 = nky1
|
||||
do 250 m=2,nxx
|
||||
do 240 i=1,nyy
|
||||
m0 = m0+1
|
||||
m1 = m1+1
|
||||
wrk(m0) = wrk(m1)
|
||||
240 continue
|
||||
m1 = m1+nuy
|
||||
250 continue
|
||||
c we partition the working space and evaluate the partial derivative
|
||||
300 iwx = 1+nxx*nyy
|
||||
iwy = iwx+mx*(kx1-nux)
|
||||
call fpbisp(tx(nux+1),nx-2*nux,ty(nuy+1),ny-2*nuy,wrk,kkx,kky,
|
||||
* x,mx,y,my,z,wrk(iwx),wrk(iwy),iwrk(1),iwrk(mx+1))
|
||||
400 return
|
||||
end
|
||||
|
||||
159
cxx/fitpack/pardeu.f
Normal file
159
cxx/fitpack/pardeu.f
Normal file
@ -0,0 +1,159 @@
|
||||
recursive subroutine pardeu(tx,nx,ty,ny,c,kx,ky,nux,nuy,x,y,z,m,
|
||||
* wrk,lwrk,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c subroutine pardeu evaluates on a set of points (x(i),y(i)),i=1,...,m
|
||||
c the partial derivative ( order nux,nuy) of a bivariate spline
|
||||
c s(x,y) of degrees kx and ky, given in the b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c call parder(tx,nx,ty,ny,c,kx,ky,nux,nuy,x,mx,y,my,z,wrk,lwrk,
|
||||
c * iwrk,kwrk,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c tx : real array, length nx, which contains the position of the
|
||||
c knots in the x-direction.
|
||||
c nx : integer, giving the total number of knots in the x-direction
|
||||
c ty : real array, length ny, which contains the position of the
|
||||
c knots in the y-direction.
|
||||
c ny : integer, giving the total number of knots in the y-direction
|
||||
c c : real array, length (nx-kx-1)*(ny-ky-1), which contains the
|
||||
c b-spline coefficients.
|
||||
c kx,ky : integer values, giving the degrees of the spline.
|
||||
c nux : integer values, specifying the order of the partial
|
||||
c nuy derivative. 0<=nux<kx, 0<=nuy<ky.
|
||||
c kx,ky : integer values, giving the degrees of the spline.
|
||||
c x : real array of dimension (mx).
|
||||
c y : real array of dimension (my).
|
||||
c m : on entry m must specify the number points. m >= 1.
|
||||
c wrk : real array of dimension lwrk. used as workspace.
|
||||
c lwrk : integer, specifying the dimension of wrk.
|
||||
c lwrk >= mx*(kx+1-nux)+my*(ky+1-nuy)+(nx-kx-1)*(ny-ky-1)
|
||||
c iwrk : integer array of dimension kwrk. used as workspace.
|
||||
c kwrk : integer, specifying the dimension of iwrk. kwrk >= mx+my.
|
||||
c
|
||||
c output parameters:
|
||||
c z : real array of dimension (m).
|
||||
c on successful exit z(i) contains the value of the
|
||||
c specified partial derivative of s(x,y) at the point
|
||||
c (x(i),y(i)),i=1,...,m.
|
||||
c ier : integer error flag
|
||||
c ier=0 : normal return
|
||||
c ier=10: invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c lwrk>=m*(kx+1-nux)+m*(ky+1-nuy)+(nx-kx-1)*(ny-ky-1),
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpbisp,fpbspl
|
||||
c
|
||||
c references :
|
||||
c de boor c : on calculating with b-splines, j. approximation theory
|
||||
c 6 (1972) 50-62.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1989
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer nx,ny,kx,ky,m,lwrk,kwrk,ier,nux,nuy
|
||||
c ..array arguments..
|
||||
integer iwrk(kwrk)
|
||||
real*8 tx(nx),ty(ny),c((nx-kx-1)*(ny-ky-1)),x(m),y(m),z(m),
|
||||
* wrk(lwrk)
|
||||
c ..local scalars..
|
||||
integer i,iwx,iwy,j,kkx,kky,kx1,ky1,lx,ly,lwest,l1,l2,mm,m0,m1,
|
||||
* nc,nkx1,nky1,nxx,nyy
|
||||
real*8 ak,fac
|
||||
c ..
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
kx1 = kx+1
|
||||
ky1 = ky+1
|
||||
nkx1 = nx-kx1
|
||||
nky1 = ny-ky1
|
||||
nc = nkx1*nky1
|
||||
if(nux.lt.0 .or. nux.ge.kx) go to 400
|
||||
if(nuy.lt.0 .or. nuy.ge.ky) go to 400
|
||||
lwest = nc +(kx1-nux)*m+(ky1-nuy)*m
|
||||
if(lwrk.lt.lwest) go to 400
|
||||
if(kwrk.lt.(m+m)) go to 400
|
||||
if (m.lt.1) go to 400
|
||||
ier = 0
|
||||
nxx = nkx1
|
||||
nyy = nky1
|
||||
kkx = kx
|
||||
kky = ky
|
||||
c the partial derivative of order (nux,nuy) of a bivariate spline of
|
||||
c degrees kx,ky is a bivariate spline of degrees kx-nux,ky-nuy.
|
||||
c we calculate the b-spline coefficients of this spline
|
||||
do 70 i=1,nc
|
||||
wrk(i) = c(i)
|
||||
70 continue
|
||||
if(nux.eq.0) go to 200
|
||||
lx = 1
|
||||
do 100 j=1,nux
|
||||
ak = kkx
|
||||
nxx = nxx-1
|
||||
l1 = lx
|
||||
m0 = 1
|
||||
do 90 i=1,nxx
|
||||
l1 = l1+1
|
||||
l2 = l1+kkx
|
||||
fac = tx(l2)-tx(l1)
|
||||
if(fac.le.0.) go to 90
|
||||
do 80 mm=1,nyy
|
||||
m1 = m0+nyy
|
||||
wrk(m0) = (wrk(m1)-wrk(m0))*ak/fac
|
||||
m0 = m0+1
|
||||
80 continue
|
||||
90 continue
|
||||
lx = lx+1
|
||||
kkx = kkx-1
|
||||
100 continue
|
||||
200 if(nuy.eq.0) go to 300
|
||||
ly = 1
|
||||
do 230 j=1,nuy
|
||||
ak = kky
|
||||
nyy = nyy-1
|
||||
l1 = ly
|
||||
do 220 i=1,nyy
|
||||
l1 = l1+1
|
||||
l2 = l1+kky
|
||||
fac = ty(l2)-ty(l1)
|
||||
if(fac.le.0.) go to 220
|
||||
m0 = i
|
||||
do 210 mm=1,nxx
|
||||
m1 = m0+1
|
||||
wrk(m0) = (wrk(m1)-wrk(m0))*ak/fac
|
||||
m0 = m0+nky1
|
||||
210 continue
|
||||
220 continue
|
||||
ly = ly+1
|
||||
kky = kky-1
|
||||
230 continue
|
||||
m0 = nyy
|
||||
m1 = nky1
|
||||
do 250 mm=2,nxx
|
||||
do 240 i=1,nyy
|
||||
m0 = m0+1
|
||||
m1 = m1+1
|
||||
wrk(m0) = wrk(m1)
|
||||
240 continue
|
||||
m1 = m1+nuy
|
||||
250 continue
|
||||
c we partition the working space and evaluate the partial derivative
|
||||
300 iwx = 1+nxx*nyy
|
||||
iwy = iwx+m*(kx1-nux)
|
||||
do 390 i=1,m
|
||||
call fpbisp(tx(nux+1),nx-2*nux,ty(nuy+1),ny-2*nuy,wrk,kkx,kky,
|
||||
* x(i),1,y(i),1,z(i),wrk(iwx),wrk(iwy),iwrk(1),iwrk(2))
|
||||
390 continue
|
||||
400 return
|
||||
end
|
||||
157
cxx/fitpack/pardtc.f
Normal file
157
cxx/fitpack/pardtc.f
Normal file
@ -0,0 +1,157 @@
|
||||
recursive subroutine pardtc(tx,nx,ty,ny,c,kx,ky,nux,nuy,
|
||||
* newc,ier)
|
||||
implicit none
|
||||
c subroutine pardtc takes the knots and coefficients of a bivariate
|
||||
c spline, and returns the coefficients for a new bivariate spline that
|
||||
c evaluates the partial derivative (order nux, nuy) of the original
|
||||
c spline.
|
||||
c
|
||||
c calling sequence:
|
||||
c call pardtc(tx,nx,ty,ny,c,kx,ky,nux,nuy,newc,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c tx : real array, length nx, which contains the position of the
|
||||
c knots in the x-direction.
|
||||
c nx : integer, giving the total number of knots in the x-direction
|
||||
c (hidden)
|
||||
c ty : real array, length ny, which contains the position of the
|
||||
c knots in the y-direction.
|
||||
c ny : integer, giving the total number of knots in the y-direction
|
||||
c (hidden)
|
||||
c c : real array, length (nx-kx-1)*(ny-ky-1), which contains the
|
||||
c b-spline coefficients.
|
||||
c kx,ky : integer values, giving the degrees of the spline.
|
||||
c nux : integer values, specifying the order of the partial
|
||||
c nuy derivative. 0<=nux<kx, 0<=nuy<ky.
|
||||
c
|
||||
c output parameters:
|
||||
c newc : real array containing the coefficients of the derivative.
|
||||
c the dimension is (nx-nux-kx-1)*(ny-nuy-ky-1).
|
||||
c ier : integer error flag
|
||||
c ier=0 : normal return
|
||||
c ier=10: invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c 0 <= nux < kx, 0 <= nuy < kyc
|
||||
c
|
||||
c other subroutines required:
|
||||
c none
|
||||
c
|
||||
c references :
|
||||
c de boor c : on calculating with b-splines, j. approximation theory
|
||||
c 6 (1972) 50-62.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c based on the subroutine "parder" by Paul Dierckx.
|
||||
c
|
||||
c author :
|
||||
c Cong Ma
|
||||
c Department of Mathematics and Applied Mathematics, U. of Cape Town
|
||||
c Cross Campus Road, Rondebosch 7700, Cape Town, South Africa.
|
||||
c e-mail : cong.ma@uct.ac.za
|
||||
c
|
||||
c latest update : may 2019
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer nx,ny,kx,ky,nux,nuy,ier, nc
|
||||
c ..array arguments..
|
||||
real*8 tx(nx),ty(ny),c((nx-kx-1)*(ny-ky-1)),
|
||||
* newc((nx-kx-1)*(ny-ky-1))
|
||||
c ..local scalars..
|
||||
integer i,j,kx1,ky1,lx,ly,l1,l2,m,m0,m1,
|
||||
* nkx1,nky1,nxx,nyy,newkx,newky
|
||||
real*8 ak,fac
|
||||
c ..
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(nux.lt.0 .or. nux.ge.kx) go to 400
|
||||
if(nuy.lt.0 .or. nuy.ge.ky) go to 400
|
||||
kx1 = kx+1
|
||||
ky1 = ky+1
|
||||
nkx1 = nx-kx1
|
||||
nky1 = ny-ky1
|
||||
nc = nkx1*nky1
|
||||
ier = 0
|
||||
nxx = nkx1
|
||||
nyy = nky1
|
||||
newkx = kx
|
||||
newky = ky
|
||||
c the partial derivative of order (nux,nuy) of a bivariate spline of
|
||||
c degrees kx,ky is a bivariate spline of degrees kx-nux,ky-nuy.
|
||||
c we calculate the b-spline coefficients of this spline
|
||||
c that is to say newkx = kx - nux, newky = ky - nuy
|
||||
do 70 i=1,nc
|
||||
newc(i) = c(i)
|
||||
70 continue
|
||||
if(nux.eq.0) go to 200
|
||||
lx = 1
|
||||
do 100 j=1,nux
|
||||
ak = newkx
|
||||
nxx = nxx-1
|
||||
l1 = lx
|
||||
m0 = 1
|
||||
do 90 i=1,nxx
|
||||
l1 = l1+1
|
||||
l2 = l1+newkx
|
||||
fac = tx(l2)-tx(l1)
|
||||
if(fac.le.0.) go to 90
|
||||
do 80 m=1,nyy
|
||||
m1 = m0+nyy
|
||||
newc(m0) = (newc(m1)-newc(m0))*ak/fac
|
||||
m0 = m0+1
|
||||
80 continue
|
||||
90 continue
|
||||
lx = lx+1
|
||||
newkx = newkx-1
|
||||
100 continue
|
||||
200 if(nuy.eq.0) go to 400
|
||||
c orig: if(nuy.eq.0) go to 300
|
||||
ly = 1
|
||||
do 230 j=1,nuy
|
||||
ak = newky
|
||||
nyy = nyy-1
|
||||
l1 = ly
|
||||
do 220 i=1,nyy
|
||||
l1 = l1+1
|
||||
l2 = l1+newky
|
||||
fac = ty(l2)-ty(l1)
|
||||
if(fac.le.0.) go to 220
|
||||
m0 = i
|
||||
do 210 m=1,nxx
|
||||
m1 = m0+1
|
||||
newc(m0) = (newc(m1)-newc(m0))*ak/fac
|
||||
m0 = m0+nky1
|
||||
210 continue
|
||||
220 continue
|
||||
ly = ly+1
|
||||
newky = newky-1
|
||||
230 continue
|
||||
m0 = nyy
|
||||
m1 = nky1
|
||||
do 250 m=2,nxx
|
||||
do 240 i=1,nyy
|
||||
m0 = m0+1
|
||||
m1 = m1+1
|
||||
newc(m0) = newc(m1)
|
||||
240 continue
|
||||
m1 = m1+nuy
|
||||
250 continue
|
||||
c300 iwx = 1+nxx*nyy
|
||||
c iwy = iwx+mx*(kx1-nux)
|
||||
c
|
||||
c from parder.f:
|
||||
c call fpbisp(tx(nux+1),nx-2*nux,ty(nuy+1),ny-2*nuy,newc,newkx,newky,
|
||||
c * x,mx,y,my,z,newc(iwx),newc(iwy),iwrk(1),iwrk(mx+1))
|
||||
c
|
||||
c from bispev.f:
|
||||
c call fpbisp(tx, nx, ty, ny, c, kx, ky,
|
||||
c * x,mx,y,my,z,wrk(1), wrk(iw), iwrk(1),iwrk(mx+1))
|
||||
c
|
||||
c from fpbisp.f:
|
||||
c fpbisp(tx, nx, ty, ny, c, kx, ky,
|
||||
c * x,mx,y,my,z,wx, wy, lx, ly)
|
||||
400 return
|
||||
end
|
||||
|
||||
392
cxx/fitpack/parsur.f
Normal file
392
cxx/fitpack/parsur.f
Normal file
@ -0,0 +1,392 @@
|
||||
recursive subroutine parsur(iopt,ipar,idim,mu,u,mv,v,f,s,nuest,
|
||||
* nvest,nu,tu,nv,tv,c,fp,wrk,lwrk,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c given the set of ordered points f(i,j) in the idim-dimensional space,
|
||||
c corresponding to grid values (u(i),v(j)) ,i=1,...,mu ; j=1,...,mv,
|
||||
c parsur determines a smooth approximating spline surface s(u,v) , i.e.
|
||||
c f1 = s1(u,v)
|
||||
c ... u(1) <= u <= u(mu) ; v(1) <= v <= v(mv)
|
||||
c fidim = sidim(u,v)
|
||||
c with sl(u,v), l=1,2,...,idim bicubic spline functions with common
|
||||
c knots tu(i),i=1,...,nu in the u-variable and tv(j),j=1,...,nv in the
|
||||
c v-variable.
|
||||
c in addition, these splines will be periodic in the variable u if
|
||||
c ipar(1) = 1 and periodic in the variable v if ipar(2) = 1.
|
||||
c if iopt=-1, parsur determines the least-squares bicubic spline
|
||||
c surface according to a given set of knots.
|
||||
c if iopt>=0, the number of knots of s(u,v) and their position
|
||||
c is chosen automatically by the routine. the smoothness of s(u,v) is
|
||||
c achieved by minimalizing the discontinuity jumps of the derivatives
|
||||
c of the splines at the knots. the amount of smoothness of s(u,v) is
|
||||
c determined by the condition that
|
||||
c fp=sumi=1,mu(sumj=1,mv(dist(f(i,j)-s(u(i),v(j)))**2))<=s,
|
||||
c with s a given non-negative constant.
|
||||
c the fit s(u,v) is given in its b-spline representation and can be
|
||||
c evaluated by means of routine surev.
|
||||
c
|
||||
c calling sequence:
|
||||
c call parsur(iopt,ipar,idim,mu,u,mv,v,f,s,nuest,nvest,nu,tu,
|
||||
c * nv,tv,c,fp,wrk,lwrk,iwrk,kwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt : integer flag. unchanged on exit.
|
||||
c on entry iopt must specify whether a least-squares surface
|
||||
c (iopt=-1) or a smoothing surface (iopt=0 or 1)must be
|
||||
c determined.
|
||||
c if iopt=0 the routine will start with the initial set of
|
||||
c knots needed for determining the least-squares polynomial
|
||||
c surface.
|
||||
c if iopt=1 the routine will continue with the set of knots
|
||||
c found at the last call of the routine.
|
||||
c attention: a call with iopt=1 must always be immediately
|
||||
c preceded by another call with iopt = 1 or iopt = 0.
|
||||
c ipar : integer array of dimension 2. unchanged on exit.
|
||||
c on entry ipar(1) must specify whether (ipar(1)=1) or not
|
||||
c (ipar(1)=0) the splines must be periodic in the variable u.
|
||||
c on entry ipar(2) must specify whether (ipar(2)=1) or not
|
||||
c (ipar(2)=0) the splines must be periodic in the variable v.
|
||||
c idim : integer. on entry idim must specify the dimension of the
|
||||
c surface. 1 <= idim <= 3. unchanged on exit.
|
||||
c mu : integer. on entry mu must specify the number of grid points
|
||||
c along the u-axis. unchanged on exit.
|
||||
c mu >= mumin where mumin=4-2*ipar(1)
|
||||
c u : real array of dimension at least (mu). before entry, u(i)
|
||||
c must be set to the u-co-ordinate of the i-th grid point
|
||||
c along the u-axis, for i=1,2,...,mu. these values must be
|
||||
c supplied in strictly ascending order. unchanged on exit.
|
||||
c mv : integer. on entry mv must specify the number of grid points
|
||||
c along the v-axis. unchanged on exit.
|
||||
c mv >= mvmin where mvmin=4-2*ipar(2)
|
||||
c v : real array of dimension at least (mv). before entry, v(j)
|
||||
c must be set to the v-co-ordinate of the j-th grid point
|
||||
c along the v-axis, for j=1,2,...,mv. these values must be
|
||||
c supplied in strictly ascending order. unchanged on exit.
|
||||
c f : real array of dimension at least (mu*mv*idim).
|
||||
c before entry, f(mu*mv*(l-1)+mv*(i-1)+j) must be set to the
|
||||
c l-th co-ordinate of the data point corresponding to the
|
||||
c the grid point (u(i),v(j)) for l=1,...,idim ,i=1,...,mu
|
||||
c and j=1,...,mv. unchanged on exit.
|
||||
c if ipar(1)=1 it is expected that f(mu*mv*(l-1)+mv*(mu-1)+j)
|
||||
c = f(mu*mv*(l-1)+j), l=1,...,idim ; j=1,...,mv
|
||||
c if ipar(2)=1 it is expected that f(mu*mv*(l-1)+mv*(i-1)+mv)
|
||||
c = f(mu*mv*(l-1)+mv*(i-1)+1), l=1,...,idim ; i=1,...,mu
|
||||
c s : real. on entry (if iopt>=0) s must specify the smoothing
|
||||
c factor. s >=0. unchanged on exit.
|
||||
c for advice on the choice of s see further comments
|
||||
c nuest : integer. unchanged on exit.
|
||||
c nvest : integer. unchanged on exit.
|
||||
c on entry, nuest and nvest must specify an upper bound for the
|
||||
c number of knots required in the u- and v-directions respect.
|
||||
c these numbers will also determine the storage space needed by
|
||||
c the routine. nuest >= 8, nvest >= 8.
|
||||
c in most practical situation nuest = mu/2, nvest=mv/2, will
|
||||
c be sufficient. always large enough are nuest=mu+4+2*ipar(1),
|
||||
c nvest = mv+4+2*ipar(2), the number of knots needed for
|
||||
c interpolation (s=0). see also further comments.
|
||||
c nu : integer.
|
||||
c unless ier=10 (in case iopt>=0), nu will contain the total
|
||||
c number of knots with respect to the u-variable, of the spline
|
||||
c surface returned. if the computation mode iopt=1 is used,
|
||||
c the value of nu should be left unchanged between subsequent
|
||||
c calls. in case iopt=-1, the value of nu should be specified
|
||||
c on entry.
|
||||
c tu : real array of dimension at least (nuest).
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c splines with respect to the u-variable, i.e. the position of
|
||||
c the interior knots tu(5),...,tu(nu-4) as well as the position
|
||||
c of the additional knots tu(1),...,tu(4) and tu(nu-3),...,
|
||||
c tu(nu) needed for the b-spline representation.
|
||||
c if the computation mode iopt=1 is used,the values of tu(1)
|
||||
c ...,tu(nu) should be left unchanged between subsequent calls.
|
||||
c if the computation mode iopt=-1 is used, the values tu(5),
|
||||
c ...tu(nu-4) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c nv : integer.
|
||||
c unless ier=10 (in case iopt>=0), nv will contain the total
|
||||
c number of knots with respect to the v-variable, of the spline
|
||||
c surface returned. if the computation mode iopt=1 is used,
|
||||
c the value of nv should be left unchanged between subsequent
|
||||
c calls. in case iopt=-1, the value of nv should be specified
|
||||
c on entry.
|
||||
c tv : real array of dimension at least (nvest).
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c splines with respect to the v-variable, i.e. the position of
|
||||
c the interior knots tv(5),...,tv(nv-4) as well as the position
|
||||
c of the additional knots tv(1),...,tv(4) and tv(nv-3),...,
|
||||
c tv(nv) needed for the b-spline representation.
|
||||
c if the computation mode iopt=1 is used,the values of tv(1)
|
||||
c ...,tv(nv) should be left unchanged between subsequent calls.
|
||||
c if the computation mode iopt=-1 is used, the values tv(5),
|
||||
c ...tv(nv-4) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c c : real array of dimension at least (nuest-4)*(nvest-4)*idim.
|
||||
c on successful exit, c contains the coefficients of the spline
|
||||
c approximation s(u,v)
|
||||
c fp : real. unless ier=10, fp contains the sum of squared
|
||||
c residuals of the spline surface returned.
|
||||
c wrk : real array of dimension (lwrk). used as workspace.
|
||||
c if the computation mode iopt=1 is used the values of
|
||||
c wrk(1),...,wrk(4) should be left unchanged between subsequent
|
||||
c calls.
|
||||
c lwrk : integer. on entry lwrk must specify the actual dimension of
|
||||
c the array wrk as declared in the calling (sub)program.
|
||||
c lwrk must not be too small.
|
||||
c lwrk >= 4+nuest*(mv*idim+11+4*ipar(1))+nvest*(11+4*ipar(2))+
|
||||
c 4*(mu+mv)+q*idim where q is the larger of mv and nuest.
|
||||
c iwrk : integer array of dimension (kwrk). used as workspace.
|
||||
c if the computation mode iopt=1 is used the values of
|
||||
c iwrk(1),.,iwrk(3) should be left unchanged between subsequent
|
||||
c calls.
|
||||
c kwrk : integer. on entry kwrk must specify the actual dimension of
|
||||
c the array iwrk as declared in the calling (sub)program.
|
||||
c kwrk >= 3+mu+mv+nuest+nvest.
|
||||
c ier : integer. unless the routine detects an error, ier contains a
|
||||
c non-positive value on exit, i.e.
|
||||
c ier=0 : normal return. the surface returned has a residual sum of
|
||||
c squares fp such that abs(fp-s)/s <= tol with tol a relat-
|
||||
c ive tolerance set to 0.001 by the program.
|
||||
c ier=-1 : normal return. the spline surface returned is an
|
||||
c interpolating surface (fp=0).
|
||||
c ier=-2 : normal return. the surface returned is the least-squares
|
||||
c polynomial surface. in this extreme case fp gives the
|
||||
c upper bound for the smoothing factor s.
|
||||
c ier=1 : error. the required storage space exceeds the available
|
||||
c storage space, as specified by the parameters nuest and
|
||||
c nvest.
|
||||
c probably causes : nuest or nvest too small. if these param-
|
||||
c eters are already large, it may also indicate that s is
|
||||
c too small
|
||||
c the approximation returned is the least-squares surface
|
||||
c according to the current set of knots. the parameter fp
|
||||
c gives the corresponding sum of squared residuals (fp>s).
|
||||
c ier=2 : error. a theoretically impossible result was found during
|
||||
c the iteration process for finding a smoothing surface with
|
||||
c fp = s. probably causes : s too small.
|
||||
c there is an approximation returned but the corresponding
|
||||
c sum of squared residuals does not satisfy the condition
|
||||
c abs(fp-s)/s < tol.
|
||||
c ier=3 : error. the maximal number of iterations maxit (set to 20
|
||||
c by the program) allowed for finding a smoothing surface
|
||||
c with fp=s has been reached. probably causes : s too small
|
||||
c there is an approximation returned but the corresponding
|
||||
c sum of squared residuals does not satisfy the condition
|
||||
c abs(fp-s)/s < tol.
|
||||
c ier=10 : error. on entry, the input data are controlled on validity
|
||||
c the following restrictions must be satisfied.
|
||||
c -1<=iopt<=1, 0<=ipar(1)<=1, 0<=ipar(2)<=1, 1 <=idim<=3
|
||||
c mu >= 4-2*ipar(1),mv >= 4-2*ipar(2), nuest >=8, nvest >= 8,
|
||||
c kwrk>=3+mu+mv+nuest+nvest,
|
||||
c lwrk >= 4+nuest*(mv*idim+11+4*ipar(1))+nvest*(11+4*ipar(2))
|
||||
c +4*(mu+mv)+max(nuest,mv)*idim
|
||||
c u(i-1)<u(i),i=2,..,mu, v(i-1)<v(i),i=2,...,mv
|
||||
c if iopt=-1: 8<=nu<=min(nuest,mu+4+2*ipar(1))
|
||||
c u(1)<tu(5)<tu(6)<...<tu(nu-4)<u(mu)
|
||||
c 8<=nv<=min(nvest,mv+4+2*ipar(2))
|
||||
c v(1)<tv(5)<tv(6)<...<tv(nv-4)<v(mv)
|
||||
c the schoenberg-whitney conditions, i.e. there must
|
||||
c be subset of grid co-ordinates uu(p) and vv(q) such
|
||||
c that tu(p) < uu(p) < tu(p+4) ,p=1,...,nu-4
|
||||
c tv(q) < vv(q) < tv(q+4) ,q=1,...,nv-4
|
||||
c (see fpchec or fpchep)
|
||||
c if iopt>=0: s>=0
|
||||
c if s=0: nuest>=mu+4+2*ipar(1)
|
||||
c nvest>=mv+4+2*ipar(2)
|
||||
c if one of these conditions is found to be violated,control
|
||||
c is immediately repassed to the calling program. in that
|
||||
c case there is no approximation returned.
|
||||
c
|
||||
c further comments:
|
||||
c by means of the parameter s, the user can control the tradeoff
|
||||
c between closeness of fit and smoothness of fit of the approximation.
|
||||
c if s is too large, the surface will be too smooth and signal will be
|
||||
c lost ; if s is too small the surface will pick up too much noise. in
|
||||
c the extreme cases the program will return an interpolating surface
|
||||
c if s=0 and the constrained least-squares polynomial surface if s is
|
||||
c very large. between these extremes, a properly chosen s will result
|
||||
c in a good compromise between closeness of fit and smoothness of fit.
|
||||
c to decide whether an approximation, corresponding to a certain s is
|
||||
c satisfactory the user is highly recommended to inspect the fits
|
||||
c graphically.
|
||||
c recommended values for s depend on the accuracy of the data values.
|
||||
c if the user has an idea of the statistical errors on the data, he
|
||||
c can also find a proper estimate for s. for, by assuming that, if he
|
||||
c specifies the right s, parsur will return a surface s(u,v) which
|
||||
c exactly reproduces the surface underlying the data he can evaluate
|
||||
c the sum(dist(f(i,j)-s(u(i),v(j)))**2) to find a good estimate for s.
|
||||
c for example, if he knows that the statistical errors on his f(i,j)-
|
||||
c values is not greater than 0.1, he may expect that a good s should
|
||||
c have a value not larger than mu*mv*(0.1)**2.
|
||||
c if nothing is known about the statistical error in f(i,j), s must
|
||||
c be determined by trial and error, taking account of the comments
|
||||
c above. the best is then to start with a very large value of s (to
|
||||
c determine the le-sq polynomial surface and the corresponding upper
|
||||
c bound fp0 for s) and then to progressively decrease the value of s
|
||||
c ( say by a factor 10 in the beginning, i.e. s=fp0/10,fp0/100,...
|
||||
c and more carefully as the approximation shows more detail) to
|
||||
c obtain closer fits.
|
||||
c to economize the search for a good s-value the program provides with
|
||||
c different modes of computation. at the first call of the routine, or
|
||||
c whenever he wants to restart with the initial set of knots the user
|
||||
c must set iopt=0.
|
||||
c if iopt = 1 the program will continue with the knots found at
|
||||
c the last call of the routine. this will save a lot of computation
|
||||
c time if parsur is called repeatedly for different values of s.
|
||||
c the number of knots of the surface returned and their location will
|
||||
c depend on the value of s and on the complexity of the shape of the
|
||||
c surface underlying the data. if the computation mode iopt = 1
|
||||
c is used, the knots returned may also depend on the s-values at
|
||||
c previous calls (if these were smaller). therefore, if after a number
|
||||
c of trials with different s-values and iopt=1,the user can finally
|
||||
c accept a fit as satisfactory, it may be worthwhile for him to call
|
||||
c parsur once more with the chosen value for s but now with iopt=0.
|
||||
c indeed, parsur may then return an approximation of the same quality
|
||||
c of fit but with fewer knots and therefore better if data reduction
|
||||
c is also an important objective for the user.
|
||||
c the number of knots may also depend on the upper bounds nuest and
|
||||
c nvest. indeed, if at a certain stage in parsur the number of knots
|
||||
c in one direction (say nu) has reached the value of its upper bound
|
||||
c (nuest), then from that moment on all subsequent knots are added
|
||||
c in the other (v) direction. this may indicate that the value of
|
||||
c nuest is too small. on the other hand, it gives the user the option
|
||||
c of limiting the number of knots the routine locates in any direction
|
||||
c for example, by setting nuest=8 (the lowest allowable value for
|
||||
c nuest), the user can indicate that he wants an approximation with
|
||||
c splines which are simple cubic polynomials in the variable u.
|
||||
c
|
||||
c other subroutines required:
|
||||
c fppasu,fpchec,fpchep,fpknot,fprati,fpgrpa,fptrnp,fpback,
|
||||
c fpbacp,fpbspl,fptrpe,fpdisc,fpgivs,fprota
|
||||
c
|
||||
c author:
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u. leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1989
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 s,fp
|
||||
integer iopt,idim,mu,mv,nuest,nvest,nu,nv,lwrk,kwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 u(mu),v(mv),f(mu*mv*idim),tu(nuest),tv(nvest),
|
||||
* c((nuest-4)*(nvest-4)*idim),wrk(lwrk)
|
||||
integer ipar(2),iwrk(kwrk)
|
||||
c ..local scalars..
|
||||
real*8 tol,ub,ue,vb,ve,peru,perv
|
||||
integer i,j,jwrk,kndu,kndv,knru,knrv,kwest,l1,l2,l3,l4,
|
||||
* lfpu,lfpv,lwest,lww,maxit,nc,mf,mumin,mvmin
|
||||
c ..function references..
|
||||
integer max0
|
||||
c ..subroutine references..
|
||||
c fppasu,fpchec,fpchep
|
||||
c ..
|
||||
c we set up the parameters tol and maxit.
|
||||
maxit = 20
|
||||
tol = 0.1e-02
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(iopt.lt.(-1) .or. iopt.gt.1) go to 200
|
||||
if(ipar(1).lt.0 .or. ipar(1).gt.1) go to 200
|
||||
if(ipar(2).lt.0 .or. ipar(2).gt.1) go to 200
|
||||
if(idim.le.0 .or. idim.gt.3) go to 200
|
||||
mumin = 4-2*ipar(1)
|
||||
if(mu.lt.mumin .or. nuest.lt.8) go to 200
|
||||
mvmin = 4-2*ipar(2)
|
||||
if(mv.lt.mvmin .or. nvest.lt.8) go to 200
|
||||
mf = mu*mv
|
||||
nc = (nuest-4)*(nvest-4)
|
||||
lwest = 4+nuest*(mv*idim+11+4*ipar(1))+nvest*(11+4*ipar(2))+
|
||||
* 4*(mu+mv)+max0(nuest,mv)*idim
|
||||
kwest = 3+mu+mv+nuest+nvest
|
||||
if(lwrk.lt.lwest .or. kwrk.lt.kwest) go to 200
|
||||
do 10 i=2,mu
|
||||
if(u(i-1).ge.u(i)) go to 200
|
||||
10 continue
|
||||
do 20 i=2,mv
|
||||
if(v(i-1).ge.v(i)) go to 200
|
||||
20 continue
|
||||
if(iopt.ge.0) go to 100
|
||||
if(nu.lt.8 .or. nu.gt.nuest) go to 200
|
||||
ub = u(1)
|
||||
ue = u(mu)
|
||||
if (ipar(1).ne.0) go to 40
|
||||
j = nu
|
||||
do 30 i=1,4
|
||||
tu(i) = ub
|
||||
tu(j) = ue
|
||||
j = j-1
|
||||
30 continue
|
||||
call fpchec(u,mu,tu,nu,3,ier)
|
||||
if(ier.ne.0) go to 200
|
||||
go to 60
|
||||
40 l1 = 4
|
||||
l2 = l1
|
||||
l3 = nu-3
|
||||
l4 = l3
|
||||
peru = ue-ub
|
||||
tu(l2) = ub
|
||||
tu(l3) = ue
|
||||
do 50 j=1,3
|
||||
l1 = l1+1
|
||||
l2 = l2-1
|
||||
l3 = l3+1
|
||||
l4 = l4-1
|
||||
tu(l2) = tu(l4)-peru
|
||||
tu(l3) = tu(l1)+peru
|
||||
50 continue
|
||||
call fpchep(u,mu,tu,nu,3,ier)
|
||||
if(ier.ne.0) go to 200
|
||||
60 if(nv.lt.8 .or. nv.gt.nvest) go to 200
|
||||
vb = v(1)
|
||||
ve = v(mv)
|
||||
if (ipar(2).ne.0) go to 80
|
||||
j = nv
|
||||
do 70 i=1,4
|
||||
tv(i) = vb
|
||||
tv(j) = ve
|
||||
j = j-1
|
||||
70 continue
|
||||
call fpchec(v,mv,tv,nv,3,ier)
|
||||
if(ier.ne.0) go to 200
|
||||
go to 150
|
||||
80 l1 = 4
|
||||
l2 = l1
|
||||
l3 = nv-3
|
||||
l4 = l3
|
||||
perv = ve-vb
|
||||
tv(l2) = vb
|
||||
tv(l3) = ve
|
||||
do 90 j=1,3
|
||||
l1 = l1+1
|
||||
l2 = l2-1
|
||||
l3 = l3+1
|
||||
l4 = l4-1
|
||||
tv(l2) = tv(l4)-perv
|
||||
tv(l3) = tv(l1)+perv
|
||||
90 continue
|
||||
call fpchep(v,mv,tv,nv,3,ier)
|
||||
if (ier.eq.0) go to 150
|
||||
go to 200
|
||||
100 if(s.lt.0.) go to 200
|
||||
if(s.eq.0. .and. (nuest.lt.(mu+4+2*ipar(1)) .or.
|
||||
* nvest.lt.(mv+4+2*ipar(2))) )go to 200
|
||||
ier = 0
|
||||
c we partition the working space and determine the spline approximation
|
||||
150 lfpu = 5
|
||||
lfpv = lfpu+nuest
|
||||
lww = lfpv+nvest
|
||||
jwrk = lwrk-4-nuest-nvest
|
||||
knru = 4
|
||||
knrv = knru+mu
|
||||
kndu = knrv+mv
|
||||
kndv = kndu+nuest
|
||||
call fppasu(iopt,ipar,idim,u,mu,v,mv,f,mf,s,nuest,nvest,
|
||||
* tol,maxit,nc,nu,tu,nv,tv,c,fp,wrk(1),wrk(2),wrk(3),wrk(4),
|
||||
* wrk(lfpu),wrk(lfpv),iwrk(1),iwrk(2),iwrk(3),iwrk(knru),
|
||||
* iwrk(knrv),iwrk(kndu),iwrk(kndv),wrk(lww),jwrk,ier)
|
||||
200 return
|
||||
end
|
||||
|
||||
275
cxx/fitpack/percur.f
Normal file
275
cxx/fitpack/percur.f
Normal file
@ -0,0 +1,275 @@
|
||||
recursive subroutine percur(iopt,m,x,y,w,k,s,nest,n,t,c,fp,
|
||||
* wrk,lwrk,iwrk,ier)
|
||||
implicit none
|
||||
c given the set of data points (x(i),y(i)) and the set of positive
|
||||
c numbers w(i),i=1,2,...,m-1, subroutine percur determines a smooth
|
||||
c periodic spline approximation of degree k with period per=x(m)-x(1).
|
||||
c if iopt=-1 percur calculates the weighted least-squares periodic
|
||||
c spline according to a given set of knots.
|
||||
c if iopt>=0 the number of knots of the spline s(x) and the position
|
||||
c t(j),j=1,2,...,n is chosen automatically by the routine. the smooth-
|
||||
c ness of s(x) is then achieved by minimalizing the discontinuity
|
||||
c jumps of the k-th derivative of s(x) at the knots t(j),j=k+2,k+3,...,
|
||||
c n-k-1. the amount of smoothness is determined by the condition that
|
||||
c f(p)=sum((w(i)*(y(i)-s(x(i))))**2) be <= s, with s a given non-
|
||||
c negative constant, called the smoothing factor.
|
||||
c the fit s(x) is given in the b-spline representation (b-spline coef-
|
||||
c ficients c(j),j=1,2,...,n-k-1) and can be evaluated by means of
|
||||
c subroutine splev.
|
||||
c
|
||||
c calling sequence:
|
||||
c call percur(iopt,m,x,y,w,k,s,nest,n,t,c,fp,wrk,
|
||||
c * lwrk,iwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt : integer flag. on entry iopt must specify whether a weighted
|
||||
c least-squares spline (iopt=-1) or a smoothing spline (iopt=
|
||||
c 0 or 1) must be determined. if iopt=0 the routine will start
|
||||
c with an initial set of knots t(i)=x(1)+(x(m)-x(1))*(i-k-1),
|
||||
c i=1,2,...,2*k+2. if iopt=1 the routine will continue with
|
||||
c the knots found at the last call of the routine.
|
||||
c attention: a call with iopt=1 must always be immediately
|
||||
c preceded by another call with iopt=1 or iopt=0.
|
||||
c unchanged on exit.
|
||||
c m : integer. on entry m must specify the number of data points.
|
||||
c m > 1. unchanged on exit.
|
||||
c x : real array of dimension at least (m). before entry, x(i)
|
||||
c must be set to the i-th value of the independent variable x,
|
||||
c for i=1,2,...,m. these values must be supplied in strictly
|
||||
c ascending order. x(m) only indicates the length of the
|
||||
c period of the spline, i.e per=x(m)-x(1).
|
||||
c unchanged on exit.
|
||||
c y : real array of dimension at least (m). before entry, y(i)
|
||||
c must be set to the i-th value of the dependent variable y,
|
||||
c for i=1,2,...,m-1. the element y(m) is not used.
|
||||
c unchanged on exit.
|
||||
c w : real array of dimension at least (m). before entry, w(i)
|
||||
c must be set to the i-th value in the set of weights. the
|
||||
c w(i) must be strictly positive. w(m) is not used.
|
||||
c see also further comments. unchanged on exit.
|
||||
c k : integer. on entry k must specify the degree of the spline.
|
||||
c 1<=k<=5. it is recommended to use cubic splines (k=3).
|
||||
c the user is strongly dissuaded from choosing k even,together
|
||||
c with a small s-value. unchanged on exit.
|
||||
c s : real.on entry (in case iopt>=0) s must specify the smoothing
|
||||
c factor. s >=0. unchanged on exit.
|
||||
c for advice on the choice of s see further comments.
|
||||
c nest : integer. on entry nest must contain an over-estimate of the
|
||||
c total number of knots of the spline returned, to indicate
|
||||
c the storage space available to the routine. nest >=2*k+2.
|
||||
c in most practical situation nest=m/2 will be sufficient.
|
||||
c always large enough is nest=m+2*k,the number of knots needed
|
||||
c for interpolation (s=0). unchanged on exit.
|
||||
c n : integer.
|
||||
c unless ier = 10 (in case iopt >=0), n will contain the
|
||||
c total number of knots of the spline approximation returned.
|
||||
c if the computation mode iopt=1 is used this value of n
|
||||
c should be left unchanged between subsequent calls.
|
||||
c in case iopt=-1, the value of n must be specified on entry.
|
||||
c t : real array of dimension at least (nest).
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline,i.e. the position of the interior knots t(k+2),t(k+3)
|
||||
c ...,t(n-k-1) as well as the position of the additional knots
|
||||
c t(1),t(2),...,t(k+1)=x(1) and t(n-k)=x(m),..,t(n) needed for
|
||||
c the b-spline representation.
|
||||
c if the computation mode iopt=1 is used, the values of t(1),
|
||||
c t(2),...,t(n) should be left unchanged between subsequent
|
||||
c calls. if the computation mode iopt=-1 is used, the values
|
||||
c t(k+2),...,t(n-k-1) must be supplied by the user, before
|
||||
c entry. see also the restrictions (ier=10).
|
||||
c c : real array of dimension at least (nest).
|
||||
c on successful exit, this array will contain the coefficients
|
||||
c c(1),c(2),..,c(n-k-1) in the b-spline representation of s(x)
|
||||
c fp : real. unless ier = 10, fp contains the weighted sum of
|
||||
c squared residuals of the spline approximation returned.
|
||||
c wrk : real array of dimension at least (m*(k+1)+nest*(8+5*k)).
|
||||
c used as working space. if the computation mode iopt=1 is
|
||||
c used, the values wrk(1),...,wrk(n) should be left unchanged
|
||||
c between subsequent calls.
|
||||
c lwrk : integer. on entry,lwrk must specify the actual dimension of
|
||||
c the array wrk as declared in the calling (sub)program. lwrk
|
||||
c must not be too small (see wrk). unchanged on exit.
|
||||
c iwrk : integer array of dimension at least (nest).
|
||||
c used as working space. if the computation mode iopt=1 is
|
||||
c used,the values iwrk(1),...,iwrk(n) should be left unchanged
|
||||
c between subsequent calls.
|
||||
c ier : integer. unless the routine detects an error, ier contains a
|
||||
c non-positive value on exit, i.e.
|
||||
c ier=0 : normal return. the spline returned has a residual sum of
|
||||
c squares fp such that abs(fp-s)/s <= tol with tol a relat-
|
||||
c ive tolerance set to 0.001 by the program.
|
||||
c ier=-1 : normal return. the spline returned is an interpolating
|
||||
c periodic spline (fp=0).
|
||||
c ier=-2 : normal return. the spline returned is the weighted least-
|
||||
c squares constant. in this extreme case fp gives the upper
|
||||
c bound fp0 for the smoothing factor s.
|
||||
c ier=1 : error. the required storage space exceeds the available
|
||||
c storage space, as specified by the parameter nest.
|
||||
c probably causes : nest too small. if nest is already
|
||||
c large (say nest > m/2), it may also indicate that s is
|
||||
c too small
|
||||
c the approximation returned is the least-squares periodic
|
||||
c spline according to the knots t(1),t(2),...,t(n). (n=nest)
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=2 : error. a theoretically impossible result was found during
|
||||
c the iteration process for finding a smoothing spline with
|
||||
c fp = s. probably causes : s too small.
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=3 : error. the maximal number of iterations maxit (set to 20
|
||||
c by the program) allowed for finding a smoothing spline
|
||||
c with fp=s has been reached. probably causes : s too small
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=10 : error. on entry, the input data are controlled on validity
|
||||
c the following restrictions must be satisfied.
|
||||
c -1<=iopt<=1, 1<=k<=5, m>1, nest>2*k+2, w(i)>0,i=1,...,m-1
|
||||
c x(1)<x(2)<...<x(m), lwrk>=(k+1)*m+nest*(8+5*k)
|
||||
c if iopt=-1: 2*k+2<=n<=min(nest,m+2*k)
|
||||
c x(1)<t(k+2)<t(k+3)<...<t(n-k-1)<x(m)
|
||||
c the schoenberg-whitney conditions, i.e. there
|
||||
c must be a subset of data points xx(j) with
|
||||
c xx(j) = x(i) or x(i)+(x(m)-x(1)) such that
|
||||
c t(j) < xx(j) < t(j+k+1), j=k+1,...,n-k-1
|
||||
c if iopt>=0: s>=0
|
||||
c if s=0 : nest >= m+2*k
|
||||
c if one of these conditions is found to be violated,control
|
||||
c is immediately repassed to the calling program. in that
|
||||
c case there is no approximation returned.
|
||||
c
|
||||
c further comments:
|
||||
c by means of the parameter s, the user can control the tradeoff
|
||||
c between closeness of fit and smoothness of fit of the approximation.
|
||||
c if s is too large, the spline will be too smooth and signal will be
|
||||
c lost ; if s is too small the spline will pick up too much noise. in
|
||||
c the extreme cases the program will return an interpolating periodic
|
||||
c spline if s=0 and the weighted least-squares constant if s is very
|
||||
c large. between these extremes, a properly chosen s will result in
|
||||
c a good compromise between closeness of fit and smoothness of fit.
|
||||
c to decide whether an approximation, corresponding to a certain s is
|
||||
c satisfactory the user is highly recommended to inspect the fits
|
||||
c graphically.
|
||||
c recommended values for s depend on the weights w(i). if these are
|
||||
c taken as 1/d(i) with d(i) an estimate of the standard deviation of
|
||||
c y(i), a good s-value should be found in the range (m-sqrt(2*m),m+
|
||||
c sqrt(2*m)). if nothing is known about the statistical error in y(i)
|
||||
c each w(i) can be set equal to one and s determined by trial and
|
||||
c error, taking account of the comments above. the best is then to
|
||||
c start with a very large value of s ( to determine the least-squares
|
||||
c constant and the corresponding upper bound fp0 for s) and then to
|
||||
c progressively decrease the value of s ( say by a factor 10 in the
|
||||
c beginning, i.e. s=fp0/10, fp0/100,...and more carefully as the
|
||||
c approximation shows more detail) to obtain closer fits.
|
||||
c to economize the search for a good s-value the program provides with
|
||||
c different modes of computation. at the first call of the routine, or
|
||||
c whenever he wants to restart with the initial set of knots the user
|
||||
c must set iopt=0.
|
||||
c if iopt=1 the program will continue with the set of knots found at
|
||||
c the last call of the routine. this will save a lot of computation
|
||||
c time if percur is called repeatedly for different values of s.
|
||||
c the number of knots of the spline returned and their location will
|
||||
c depend on the value of s and on the complexity of the shape of the
|
||||
c function underlying the data. but, if the computation mode iopt=1
|
||||
c is used, the knots returned may also depend on the s-values at
|
||||
c previous calls (if these were smaller). therefore, if after a number
|
||||
c of trials with different s-values and iopt=1, the user can finally
|
||||
c accept a fit as satisfactory, it may be worthwhile for him to call
|
||||
c percur once more with the selected value for s but now with iopt=0.
|
||||
c indeed, percur may then return an approximation of the same quality
|
||||
c of fit but with fewer knots and therefore better if data reduction
|
||||
c is also an important objective for the user.
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpbacp,fpbspl,fpchep,fpperi,fpdisc,fpgivs,fpknot,fprati,fprota
|
||||
c
|
||||
c references:
|
||||
c dierckx p. : algorithms for smoothing data with periodic and
|
||||
c parametric splines, computer graphics and image
|
||||
c processing 20 (1982) 171-184.
|
||||
c dierckx p. : algorithms for smoothing data with periodic and param-
|
||||
c etric splines, report tw55, dept. computer science,
|
||||
c k.u.leuven, 1981.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u. leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : may 1979
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 s,fp
|
||||
integer iopt,m,k,nest,n,lwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),y(m),w(m),t(nest),c(nest),wrk(lwrk)
|
||||
integer iwrk(nest)
|
||||
c ..local scalars..
|
||||
real*8 per,tol
|
||||
integer i,ia1,ia2,ib,ifp,ig1,ig2,iq,iz,i1,i2,j1,j2,k1,k2,lwest,
|
||||
* maxit,m1,nmin
|
||||
c ..subroutine references..
|
||||
c perper,pcheck
|
||||
c ..
|
||||
c we set up the parameters tol and maxit
|
||||
maxit = 20
|
||||
tol = 0.1e-02
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(k.le.0 .or. k.gt.5) go to 50
|
||||
k1 = k+1
|
||||
k2 = k1+1
|
||||
if(iopt.lt.(-1) .or. iopt.gt.1) go to 50
|
||||
nmin = 2*k1
|
||||
if(m.lt.2 .or. nest.lt.nmin) go to 50
|
||||
lwest = m*k1+nest*(8+5*k)
|
||||
if(lwrk.lt.lwest) go to 50
|
||||
m1 = m-1
|
||||
do 10 i=1,m1
|
||||
if(x(i).ge.x(i+1) .or. w(i).le.0.) go to 50
|
||||
10 continue
|
||||
if(iopt.ge.0) go to 30
|
||||
if(n.le.nmin .or. n.gt.nest) go to 50
|
||||
per = x(m)-x(1)
|
||||
j1 = k1
|
||||
t(j1) = x(1)
|
||||
i1 = n-k
|
||||
t(i1) = x(m)
|
||||
j2 = j1
|
||||
i2 = i1
|
||||
do 20 i=1,k
|
||||
i1 = i1+1
|
||||
i2 = i2-1
|
||||
j1 = j1+1
|
||||
j2 = j2-1
|
||||
t(j2) = t(i2)-per
|
||||
t(i1) = t(j1)+per
|
||||
20 continue
|
||||
call fpchep(x,m,t,n,k,ier)
|
||||
if (ier.eq.0) go to 40
|
||||
go to 50
|
||||
30 if(s.lt.0.) go to 50
|
||||
if(s.eq.0. .and. nest.lt.(m+2*k)) go to 50
|
||||
ier = 0
|
||||
c we partition the working space and determine the spline approximation.
|
||||
40 ifp = 1
|
||||
iz = ifp+nest
|
||||
ia1 = iz+nest
|
||||
ia2 = ia1+nest*k1
|
||||
ib = ia2+nest*k
|
||||
ig1 = ib+nest*k2
|
||||
ig2 = ig1+nest*k2
|
||||
iq = ig2+nest*k1
|
||||
call fpperi(iopt,x,y,w,m,k,s,nest,tol,maxit,k1,k2,n,t,c,fp,
|
||||
* wrk(ifp),wrk(iz),wrk(ia1),wrk(ia2),wrk(ib),wrk(ig1),wrk(ig2),
|
||||
* wrk(iq),iwrk,ier)
|
||||
50 return
|
||||
end
|
||||
467
cxx/fitpack/pogrid.f
Normal file
467
cxx/fitpack/pogrid.f
Normal file
@ -0,0 +1,467 @@
|
||||
recursive subroutine pogrid(iopt,ider,mu,u,mv,v,z,z0,r,s,
|
||||
* nuest,nvest,nu,tu,nv,tv,c,fp,wrk,lwrk,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c subroutine pogrid fits a function f(x,y) to a set of data points
|
||||
c z(i,j) given at the nodes (x,y)=(u(i)*cos(v(j)),u(i)*sin(v(j))),
|
||||
c i=1,...,mu ; j=1,...,mv , of a radius-angle grid over a disc
|
||||
c x ** 2 + y ** 2 <= r ** 2 .
|
||||
c
|
||||
c this approximation problem is reduced to the determination of a
|
||||
c bicubic spline s(u,v) smoothing the data (u(i),v(j),z(i,j)) on the
|
||||
c rectangle 0<=u<=r, v(1)<=v<=v(1)+2*pi
|
||||
c in order to have continuous partial derivatives
|
||||
c i+j
|
||||
c d f(0,0)
|
||||
c g(i,j) = ----------
|
||||
c i j
|
||||
c dx dy
|
||||
c
|
||||
c s(u,v)=f(x,y) must satisfy the following conditions
|
||||
c
|
||||
c (1) s(0,v) = g(0,0) v(1)<=v<= v(1)+2*pi
|
||||
c
|
||||
c d s(0,v)
|
||||
c (2) -------- = cos(v)*g(1,0)+sin(v)*g(0,1) v(1)<=v<= v(1)+2*pi
|
||||
c d u
|
||||
c
|
||||
c moreover, s(u,v) must be periodic in the variable v, i.e.
|
||||
c
|
||||
c j j
|
||||
c d s(u,vb) d s(u,ve)
|
||||
c (3) ---------- = --------- 0 <=u<= r, j=0,1,2 , vb=v(1),
|
||||
c j j ve=vb+2*pi
|
||||
c d v d v
|
||||
c
|
||||
c the number of knots of s(u,v) and their position tu(i),i=1,2,...,nu;
|
||||
c tv(j),j=1,2,...,nv, is chosen automatically by the routine. the
|
||||
c smoothness of s(u,v) is achieved by minimalizing the discontinuity
|
||||
c jumps of the derivatives of the spline at the knots. the amount of
|
||||
c smoothness of s(u,v) is determined by the condition that
|
||||
c fp=sumi=1,mu(sumj=1,mv((z(i,j)-s(u(i),v(j)))**2))+(z0-g(0,0))**2<=s,
|
||||
c with s a given non-negative constant.
|
||||
c the fit s(u,v) is given in its b-spline representation and can be
|
||||
c evaluated by means of routine bispev. f(x,y) = s(u,v) can also be
|
||||
c evaluated by means of function program evapol.
|
||||
c
|
||||
c calling sequence:
|
||||
c call pogrid(iopt,ider,mu,u,mv,v,z,z0,r,s,nuest,nvest,nu,tu,
|
||||
c * ,nv,tv,c,fp,wrk,lwrk,iwrk,kwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt : integer array of dimension 3, specifying different options.
|
||||
c unchanged on exit.
|
||||
c iopt(1):on entry iopt(1) must specify whether a least-squares spline
|
||||
c (iopt(1)=-1) or a smoothing spline (iopt(1)=0 or 1) must be
|
||||
c determined.
|
||||
c if iopt(1)=0 the routine will start with an initial set of
|
||||
c knots tu(i)=0,tu(i+4)=r,i=1,...,4;tv(i)=v(1)+(i-4)*2*pi,i=1,.
|
||||
c ...,8.
|
||||
c if iopt(1)=1 the routine will continue with the set of knots
|
||||
c found at the last call of the routine.
|
||||
c attention: a call with iopt(1)=1 must always be immediately
|
||||
c preceded by another call with iopt(1) = 1 or iopt(1) = 0.
|
||||
c iopt(2):on entry iopt(2) must specify the requested order of conti-
|
||||
c nuity for f(x,y) at the origin.
|
||||
c if iopt(2)=0 only condition (1) must be fulfilled and
|
||||
c if iopt(2)=1 conditions (1)+(2) must be fulfilled.
|
||||
c iopt(3):on entry iopt(3) must specify whether (iopt(3)=1) or not
|
||||
c (iopt(3)=0) the approximation f(x,y) must vanish at the
|
||||
c boundary of the approximation domain.
|
||||
c ider : integer array of dimension 2, specifying different options.
|
||||
c unchanged on exit.
|
||||
c ider(1):on entry ider(1) must specify whether (ider(1)=0 or 1) or not
|
||||
c (ider(1)=-1) there is a data value z0 at the origin.
|
||||
c if ider(1)=1, z0 will be considered to be the right function
|
||||
c value, and it will be fitted exactly (g(0,0)=z0=c(1)).
|
||||
c if ider(1)=0, z0 will be considered to be a data value just
|
||||
c like the other data values z(i,j).
|
||||
c ider(2):on entry ider(2) must specify whether (ider(2)=1) or not
|
||||
c (ider(2)=0) f(x,y) must have vanishing partial derivatives
|
||||
c g(1,0) and g(0,1) at the origin. (in case iopt(2)=1)
|
||||
c mu : integer. on entry mu must specify the number of grid points
|
||||
c along the u-axis. unchanged on exit.
|
||||
c mu >= mumin where mumin=4-iopt(3)-ider(2) if ider(1)<0
|
||||
c =3-iopt(3)-ider(2) if ider(1)>=0
|
||||
c u : real array of dimension at least (mu). before entry, u(i)
|
||||
c must be set to the u-co-ordinate of the i-th grid point
|
||||
c along the u-axis, for i=1,2,...,mu. these values must be
|
||||
c positive and supplied in strictly ascending order.
|
||||
c unchanged on exit.
|
||||
c mv : integer. on entry mv must specify the number of grid points
|
||||
c along the v-axis. mv > 3 . unchanged on exit.
|
||||
c v : real array of dimension at least (mv). before entry, v(j)
|
||||
c must be set to the v-co-ordinate of the j-th grid point
|
||||
c along the v-axis, for j=1,2,...,mv. these values must be
|
||||
c supplied in strictly ascending order. unchanged on exit.
|
||||
c -pi <= v(1) < pi , v(mv) < v(1)+2*pi.
|
||||
c z : real array of dimension at least (mu*mv).
|
||||
c before entry, z(mv*(i-1)+j) must be set to the data value at
|
||||
c the grid point (u(i),v(j)) for i=1,...,mu and j=1,...,mv.
|
||||
c unchanged on exit.
|
||||
c z0 : real value. on entry (if ider(1) >=0 ) z0 must specify the
|
||||
c data value at the origin. unchanged on exit.
|
||||
c r : real value. on entry r must specify the radius of the disk.
|
||||
c r>=u(mu) (>u(mu) if iopt(3)=1). unchanged on exit.
|
||||
c s : real. on entry (if iopt(1)>=0) s must specify the smoothing
|
||||
c factor. s >=0. unchanged on exit.
|
||||
c for advice on the choice of s see further comments
|
||||
c nuest : integer. unchanged on exit.
|
||||
c nvest : integer. unchanged on exit.
|
||||
c on entry, nuest and nvest must specify an upper bound for the
|
||||
c number of knots required in the u- and v-directions respect.
|
||||
c these numbers will also determine the storage space needed by
|
||||
c the routine. nuest >= 8, nvest >= 8.
|
||||
c in most practical situation nuest = mu/2, nvest=mv/2, will
|
||||
c be sufficient. always large enough are nuest=mu+5+iopt(2)+
|
||||
c iopt(3), nvest = mv+7, the number of knots needed for
|
||||
c interpolation (s=0). see also further comments.
|
||||
c nu : integer.
|
||||
c unless ier=10 (in case iopt(1)>=0), nu will contain the total
|
||||
c number of knots with respect to the u-variable, of the spline
|
||||
c approximation returned. if the computation mode iopt(1)=1 is
|
||||
c used, the value of nu should be left unchanged between sub-
|
||||
c sequent calls. in case iopt(1)=-1, the value of nu should be
|
||||
c specified on entry.
|
||||
c tu : real array of dimension at least (nuest).
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline with respect to the u-variable, i.e. the position of
|
||||
c the interior knots tu(5),...,tu(nu-4) as well as the position
|
||||
c of the additional knots tu(1)=...=tu(4)=0 and tu(nu-3)=...=
|
||||
c tu(nu)=r needed for the b-spline representation.
|
||||
c if the computation mode iopt(1)=1 is used,the values of tu(1)
|
||||
c ...,tu(nu) should be left unchanged between subsequent calls.
|
||||
c if the computation mode iopt(1)=-1 is used, the values tu(5),
|
||||
c ...tu(nu-4) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c nv : integer.
|
||||
c unless ier=10 (in case iopt(1)>=0), nv will contain the total
|
||||
c number of knots with respect to the v-variable, of the spline
|
||||
c approximation returned. if the computation mode iopt(1)=1 is
|
||||
c used, the value of nv should be left unchanged between sub-
|
||||
c sequent calls. in case iopt(1) = -1, the value of nv should
|
||||
c be specified on entry.
|
||||
c tv : real array of dimension at least (nvest).
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline with respect to the v-variable, i.e. the position of
|
||||
c the interior knots tv(5),...,tv(nv-4) as well as the position
|
||||
c of the additional knots tv(1),...,tv(4) and tv(nv-3),...,
|
||||
c tv(nv) needed for the b-spline representation.
|
||||
c if the computation mode iopt(1)=1 is used,the values of tv(1)
|
||||
c ...,tv(nv) should be left unchanged between subsequent calls.
|
||||
c if the computation mode iopt(1)=-1 is used, the values tv(5),
|
||||
c ...tv(nv-4) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c c : real array of dimension at least (nuest-4)*(nvest-4).
|
||||
c on successful exit, c contains the coefficients of the spline
|
||||
c approximation s(u,v)
|
||||
c fp : real. unless ier=10, fp contains the sum of squared
|
||||
c residuals of the spline approximation returned.
|
||||
c wrk : real array of dimension (lwrk). used as workspace.
|
||||
c if the computation mode iopt(1)=1 is used the values of
|
||||
c wrk(1),...,wrk(8) should be left unchanged between subsequent
|
||||
c calls.
|
||||
c lwrk : integer. on entry lwrk must specify the actual dimension of
|
||||
c the array wrk as declared in the calling (sub)program.
|
||||
c lwrk must not be too small.
|
||||
c lwrk >= 8+nuest*(mv+nvest+3)+nvest*21+4*mu+6*mv+q
|
||||
c where q is the larger of (mv+nvest) and nuest.
|
||||
c iwrk : integer array of dimension (kwrk). used as workspace.
|
||||
c if the computation mode iopt(1)=1 is used the values of
|
||||
c iwrk(1),.,iwrk(4) should be left unchanged between subsequent
|
||||
c calls.
|
||||
c kwrk : integer. on entry kwrk must specify the actual dimension of
|
||||
c the array iwrk as declared in the calling (sub)program.
|
||||
c kwrk >= 4+mu+mv+nuest+nvest.
|
||||
c ier : integer. unless the routine detects an error, ier contains a
|
||||
c non-positive value on exit, i.e.
|
||||
c ier=0 : normal return. the spline returned has a residual sum of
|
||||
c squares fp such that abs(fp-s)/s <= tol with tol a relat-
|
||||
c ive tolerance set to 0.001 by the program.
|
||||
c ier=-1 : normal return. the spline returned is an interpolating
|
||||
c spline (fp=0).
|
||||
c ier=-2 : normal return. the spline returned is the least-squares
|
||||
c constrained polynomial. in this extreme case fp gives the
|
||||
c upper bound for the smoothing factor s.
|
||||
c ier=1 : error. the required storage space exceeds the available
|
||||
c storage space, as specified by the parameters nuest and
|
||||
c nvest.
|
||||
c probably causes : nuest or nvest too small. if these param-
|
||||
c eters are already large, it may also indicate that s is
|
||||
c too small
|
||||
c the approximation returned is the least-squares spline
|
||||
c according to the current set of knots. the parameter fp
|
||||
c gives the corresponding sum of squared residuals (fp>s).
|
||||
c ier=2 : error. a theoretically impossible result was found during
|
||||
c the iteration process for finding a smoothing spline with
|
||||
c fp = s. probably causes : s too small.
|
||||
c there is an approximation returned but the corresponding
|
||||
c sum of squared residuals does not satisfy the condition
|
||||
c abs(fp-s)/s < tol.
|
||||
c ier=3 : error. the maximal number of iterations maxit (set to 20
|
||||
c by the program) allowed for finding a smoothing spline
|
||||
c with fp=s has been reached. probably causes : s too small
|
||||
c there is an approximation returned but the corresponding
|
||||
c sum of squared residuals does not satisfy the condition
|
||||
c abs(fp-s)/s < tol.
|
||||
c ier=10 : error. on entry, the input data are controlled on validity
|
||||
c the following restrictions must be satisfied.
|
||||
c -1<=iopt(1)<=1, 0<=iopt(2)<=1, 0<=iopt(3)<=1,
|
||||
c -1<=ider(1)<=1, 0<=ider(2)<=1, ider(2)=0 if iopt(2)=0.
|
||||
c mu >= mumin (see above), mv >= 4, nuest >=8, nvest >= 8,
|
||||
c kwrk>=4+mu+mv+nuest+nvest,
|
||||
c lwrk >= 8+nuest*(mv+nvest+3)+nvest*21+4*mu+6*mv+
|
||||
c max(nuest,mv+nvest)
|
||||
c 0< u(i-1)<u(i)<=r,i=2,..,mu, (< r if iopt(3)=1)
|
||||
c -pi<=v(1)< pi, v(1)<v(i-1)<v(i)<v(1)+2*pi, i=3,...,mv
|
||||
c if iopt(1)=-1: 8<=nu<=min(nuest,mu+5+iopt(2)+iopt(3))
|
||||
c 0<tu(5)<tu(6)<...<tu(nu-4)<r
|
||||
c 8<=nv<=min(nvest,mv+7)
|
||||
c v(1)<tv(5)<tv(6)<...<tv(nv-4)<v(1)+2*pi
|
||||
c the schoenberg-whitney conditions, i.e. there must
|
||||
c be subset of grid co-ordinates uu(p) and vv(q) such
|
||||
c that tu(p) < uu(p) < tu(p+4) ,p=1,...,nu-4
|
||||
c (iopt(2)=1 and iopt(3)=1 also count for a uu-value
|
||||
c tv(q) < vv(q) < tv(q+4) ,q=1,...,nv-4
|
||||
c (vv(q) is either a value v(j) or v(j)+2*pi)
|
||||
c if iopt(1)>=0: s>=0
|
||||
c if s=0: nuest>=mu+5+iopt(2)+iopt(3), nvest>=mv+7
|
||||
c if one of these conditions is found to be violated,control
|
||||
c is immediately repassed to the calling program. in that
|
||||
c case there is no approximation returned.
|
||||
c
|
||||
c further comments:
|
||||
c pogrid does not allow individual weighting of the data-values.
|
||||
c so, if these were determined to widely different accuracies, then
|
||||
c perhaps the general data set routine polar should rather be used
|
||||
c in spite of efficiency.
|
||||
c by means of the parameter s, the user can control the tradeoff
|
||||
c between closeness of fit and smoothness of fit of the approximation.
|
||||
c if s is too large, the spline will be too smooth and signal will be
|
||||
c lost ; if s is too small the spline will pick up too much noise. in
|
||||
c the extreme cases the program will return an interpolating spline if
|
||||
c s=0 and the constrained least-squares polynomial(degrees 3,0)if s is
|
||||
c very large. between these extremes, a properly chosen s will result
|
||||
c in a good compromise between closeness of fit and smoothness of fit.
|
||||
c to decide whether an approximation, corresponding to a certain s is
|
||||
c satisfactory the user is highly recommended to inspect the fits
|
||||
c graphically.
|
||||
c recommended values for s depend on the accuracy of the data values.
|
||||
c if the user has an idea of the statistical errors on the data, he
|
||||
c can also find a proper estimate for s. for, by assuming that, if he
|
||||
c specifies the right s, pogrid will return a spline s(u,v) which
|
||||
c exactly reproduces the function underlying the data he can evaluate
|
||||
c the sum((z(i,j)-s(u(i),v(j)))**2) to find a good estimate for this s
|
||||
c for example, if he knows that the statistical errors on his z(i,j)-
|
||||
c values is not greater than 0.1, he may expect that a good s should
|
||||
c have a value not larger than mu*mv*(0.1)**2.
|
||||
c if nothing is known about the statistical error in z(i,j), s must
|
||||
c be determined by trial and error, taking account of the comments
|
||||
c above. the best is then to start with a very large value of s (to
|
||||
c determine the least-squares polynomial and the corresponding upper
|
||||
c bound fp0 for s) and then to progressively decrease the value of s
|
||||
c ( say by a factor 10 in the beginning, i.e. s=fp0/10,fp0/100,...
|
||||
c and more carefully as the approximation shows more detail) to
|
||||
c obtain closer fits.
|
||||
c to economize the search for a good s-value the program provides with
|
||||
c different modes of computation. at the first call of the routine, or
|
||||
c whenever he wants to restart with the initial set of knots the user
|
||||
c must set iopt(1)=0.
|
||||
c if iopt(1) = 1 the program will continue with the knots found at
|
||||
c the last call of the routine. this will save a lot of computation
|
||||
c time if pogrid is called repeatedly for different values of s.
|
||||
c the number of knots of the spline returned and their location will
|
||||
c depend on the value of s and on the complexity of the shape of the
|
||||
c function underlying the data. if the computation mode iopt(1) = 1
|
||||
c is used, the knots returned may also depend on the s-values at
|
||||
c previous calls (if these were smaller). therefore, if after a number
|
||||
c of trials with different s-values and iopt(1)=1,the user can finally
|
||||
c accept a fit as satisfactory, it may be worthwhile for him to call
|
||||
c pogrid once more with the chosen value for s but now with iopt(1)=0.
|
||||
c indeed, pogrid may then return an approximation of the same quality
|
||||
c of fit but with fewer knots and therefore better if data reduction
|
||||
c is also an important objective for the user.
|
||||
c the number of knots may also depend on the upper bounds nuest and
|
||||
c nvest. indeed, if at a certain stage in pogrid the number of knots
|
||||
c in one direction (say nu) has reached the value of its upper bound
|
||||
c (nuest), then from that moment on all subsequent knots are added
|
||||
c in the other (v) direction. this may indicate that the value of
|
||||
c nuest is too small. on the other hand, it gives the user the option
|
||||
c of limiting the number of knots the routine locates in any direction
|
||||
c for example, by setting nuest=8 (the lowest allowable value for
|
||||
c nuest), the user can indicate that he wants an approximation which
|
||||
c is a simple cubic polynomial in the variable u.
|
||||
c
|
||||
c other subroutines required:
|
||||
c fppogr,fpchec,fpchep,fpknot,fpopdi,fprati,fpgrdi,fpsysy,fpback,
|
||||
c fpbacp,fpbspl,fpcyt1,fpcyt2,fpdisc,fpgivs,fprota
|
||||
c
|
||||
c references:
|
||||
c dierckx p. : fast algorithms for smoothing data over a disc or a
|
||||
c sphere using tensor product splines, in "algorithms
|
||||
c for approximation", ed. j.c.mason and m.g.cox,
|
||||
c clarendon press oxford, 1987, pp. 51-65
|
||||
c dierckx p. : fast algorithms for smoothing data over a disc or a
|
||||
c sphere using tensor product splines, report tw73, dept.
|
||||
c computer science,k.u.leuven, 1985.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u. leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : july 1985
|
||||
c latest update : march 1989
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 z0,r,s,fp
|
||||
integer mu,mv,nuest,nvest,nu,nv,lwrk,kwrk,ier
|
||||
c ..array arguments..
|
||||
integer iopt(3),ider(2),iwrk(kwrk)
|
||||
real*8 u(mu),v(mv),z(mu*mv),c((nuest-4)*(nvest-4)),tu(nuest),
|
||||
* tv(nvest),wrk(lwrk)
|
||||
c ..local scalars..
|
||||
real*8 per,pi,tol,uu,ve,zmax,zmin,one,half,rn,zb
|
||||
integer i,i1,i2,j,jwrk,j1,j2,kndu,kndv,knru,knrv,kwest,l,
|
||||
* ldz,lfpu,lfpv,lwest,lww,m,maxit,mumin,muu,nc
|
||||
c ..function references..
|
||||
real*8 datan2
|
||||
integer max0
|
||||
c ..subroutine references..
|
||||
c fpchec,fpchep,fppogr
|
||||
c ..
|
||||
c set constants
|
||||
one = 1d0
|
||||
half = 0.5e0
|
||||
pi = datan2(0d0,-one)
|
||||
per = pi+pi
|
||||
ve = v(1)+per
|
||||
c we set up the parameters tol and maxit.
|
||||
maxit = 20
|
||||
tol = 0.1e-02
|
||||
c before starting computations, a data check is made. if the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(iopt(1).lt.(-1) .or. iopt(1).gt.1) go to 200
|
||||
if(iopt(2).lt.0 .or. iopt(2).gt.1) go to 200
|
||||
if(iopt(3).lt.0 .or. iopt(3).gt.1) go to 200
|
||||
if(ider(1).lt.(-1) .or. ider(1).gt.1) go to 200
|
||||
if(ider(2).lt.0 .or. ider(2).gt.1) go to 200
|
||||
if(ider(2).eq.1 .and. iopt(2).eq.0) go to 200
|
||||
mumin = 4-iopt(3)-ider(2)
|
||||
if(ider(1).ge.0) mumin = mumin-1
|
||||
if(mu.lt.mumin .or. mv.lt.4) go to 200
|
||||
if(nuest.lt.8 .or. nvest.lt.8) go to 200
|
||||
m = mu*mv
|
||||
nc = (nuest-4)*(nvest-4)
|
||||
lwest = 8+nuest*(mv+nvest+3)+21*nvest+4*mu+6*mv+
|
||||
* max0(nuest,mv+nvest)
|
||||
kwest = 4+mu+mv+nuest+nvest
|
||||
if(lwrk.lt.lwest .or. kwrk.lt.kwest) go to 200
|
||||
if(u(1).le.0. .or. u(mu).gt.r) go to 200
|
||||
if(iopt(3).eq.0) go to 10
|
||||
if(u(mu).eq.r) go to 200
|
||||
10 if(mu.eq.1) go to 30
|
||||
do 20 i=2,mu
|
||||
if(u(i-1).ge.u(i)) go to 200
|
||||
20 continue
|
||||
30 if(v(1).lt. (-pi) .or. v(1).ge.pi ) go to 200
|
||||
if(v(mv).ge.v(1)+per) go to 200
|
||||
do 40 i=2,mv
|
||||
if(v(i-1).ge.v(i)) go to 200
|
||||
40 continue
|
||||
if(iopt(1).gt.0) go to 140
|
||||
c if not given, we compute an estimate for z0.
|
||||
if(ider(1).lt.0) go to 50
|
||||
zb = z0
|
||||
go to 70
|
||||
50 zb = 0.
|
||||
do 60 i=1,mv
|
||||
zb = zb+z(i)
|
||||
60 continue
|
||||
rn = mv
|
||||
zb = zb/rn
|
||||
c we determine the range of z-values.
|
||||
70 zmin = zb
|
||||
zmax = zb
|
||||
do 80 i=1,m
|
||||
if(z(i).lt.zmin) zmin = z(i)
|
||||
if(z(i).gt.zmax) zmax = z(i)
|
||||
80 continue
|
||||
wrk(5) = zb
|
||||
wrk(6) = 0.
|
||||
wrk(7) = 0.
|
||||
wrk(8) = zmax -zmin
|
||||
iwrk(4) = mu
|
||||
if(iopt(1).eq.0) go to 140
|
||||
if(nu.lt.8 .or. nu.gt.nuest) go to 200
|
||||
if(nv.lt.11 .or. nv.gt.nvest) go to 200
|
||||
j = nu
|
||||
do 90 i=1,4
|
||||
tu(i) = 0.
|
||||
tu(j) = r
|
||||
j = j-1
|
||||
90 continue
|
||||
l = 9
|
||||
wrk(l) = 0.
|
||||
if(iopt(2).eq.0) go to 100
|
||||
l = l+1
|
||||
uu = u(1)
|
||||
if(uu.gt.tu(5)) uu = tu(5)
|
||||
wrk(l) = uu*half
|
||||
100 do 110 i=1,mu
|
||||
l = l+1
|
||||
wrk(l) = u(i)
|
||||
110 continue
|
||||
if(iopt(3).eq.0) go to 120
|
||||
l = l+1
|
||||
wrk(l) = r
|
||||
120 muu = l-8
|
||||
call fpchec(wrk(9),muu,tu,nu,3,ier)
|
||||
if(ier.ne.0) go to 200
|
||||
j1 = 4
|
||||
tv(j1) = v(1)
|
||||
i1 = nv-3
|
||||
tv(i1) = ve
|
||||
j2 = j1
|
||||
i2 = i1
|
||||
do 130 i=1,3
|
||||
i1 = i1+1
|
||||
i2 = i2-1
|
||||
j1 = j1+1
|
||||
j2 = j2-1
|
||||
tv(j2) = tv(i2)-per
|
||||
tv(i1) = tv(j1)+per
|
||||
130 continue
|
||||
l = 9
|
||||
do 135 i=1,mv
|
||||
wrk(l) = v(i)
|
||||
l = l+1
|
||||
135 continue
|
||||
wrk(l) = ve
|
||||
call fpchep(wrk(9),mv+1,tv,nv,3,ier)
|
||||
if (ier.eq.0) go to 150
|
||||
go to 200
|
||||
140 if(s.lt.0.) go to 200
|
||||
if(s.eq.0. .and. (nuest.lt.(mu+5+iopt(2)+iopt(3)) .or.
|
||||
* nvest.lt.(mv+7)) ) go to 200
|
||||
c we partition the working space and determine the spline approximation
|
||||
150 ldz = 5
|
||||
lfpu = 9
|
||||
lfpv = lfpu+nuest
|
||||
lww = lfpv+nvest
|
||||
jwrk = lwrk-8-nuest-nvest
|
||||
knru = 5
|
||||
knrv = knru+mu
|
||||
kndu = knrv+mv
|
||||
kndv = kndu+nuest
|
||||
call fppogr(iopt,ider,u,mu,v,mv,z,m,zb,r,s,nuest,nvest,tol,maxit,
|
||||
* nc,nu,tu,nv,tv,c,fp,wrk(1),wrk(2),wrk(3),wrk(4),wrk(lfpu),
|
||||
* wrk(lfpv),wrk(ldz),wrk(8),iwrk(1),iwrk(2),iwrk(3),iwrk(4),
|
||||
* iwrk(knru),iwrk(knrv),iwrk(kndu),iwrk(kndv),wrk(lww),jwrk,ier)
|
||||
200 return
|
||||
end
|
||||
|
||||
451
cxx/fitpack/polar.f
Normal file
451
cxx/fitpack/polar.f
Normal file
@ -0,0 +1,451 @@
|
||||
recursive subroutine polar(iopt,m,x,y,z,w,rad,s,nuest,nvest,
|
||||
* eps,nu,tu,nv,tv,u,v,c,fp,wrk1,lwrk1,wrk2,lwrk2,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c subroutine polar fits a smooth function f(x,y) to a set of data
|
||||
c points (x(i),y(i),z(i)) scattered arbitrarily over an approximation
|
||||
c domain x**2+y**2 <= rad(atan(y/x))**2. through the transformation
|
||||
c x = u*rad(v)*cos(v) , y = u*rad(v)*sin(v)
|
||||
c the approximation problem is reduced to the determination of a bi-
|
||||
c cubic spline s(u,v) fitting a corresponding set of data points
|
||||
c (u(i),v(i),z(i)) on the rectangle 0<=u<=1,-pi<=v<=pi.
|
||||
c in order to have continuous partial derivatives
|
||||
c i+j
|
||||
c d f(0,0)
|
||||
c g(i,j) = ----------
|
||||
c i j
|
||||
c dx dy
|
||||
c
|
||||
c s(u,v)=f(x,y) must satisfy the following conditions
|
||||
c
|
||||
c (1) s(0,v) = g(0,0) -pi <=v<= pi.
|
||||
c
|
||||
c d s(0,v)
|
||||
c (2) -------- = rad(v)*(cos(v)*g(1,0)+sin(v)*g(0,1))
|
||||
c d u
|
||||
c -pi <=v<= pi
|
||||
c 2
|
||||
c d s(0,v) 2 2 2
|
||||
c (3) -------- = rad(v)*(cos(v)*g(2,0)+sin(v)*g(0,2)+sin(2*v)*g(1,1))
|
||||
c 2
|
||||
c d u -pi <=v<= pi
|
||||
c
|
||||
c moreover, s(u,v) must be periodic in the variable v, i.e.
|
||||
c
|
||||
c j j
|
||||
c d s(u,-pi) d s(u,pi)
|
||||
c (4) ---------- = --------- 0 <=u<= 1, j=0,1,2
|
||||
c j j
|
||||
c d v d v
|
||||
c
|
||||
c if iopt(1) < 0 circle calculates a weighted least-squares spline
|
||||
c according to a given set of knots in u- and v- direction.
|
||||
c if iopt(1) >=0, the number of knots in each direction and their pos-
|
||||
c ition tu(j),j=1,2,...,nu ; tv(j),j=1,2,...,nv are chosen automatical-
|
||||
c ly by the routine. the smoothness of s(u,v) is then achieved by mini-
|
||||
c malizing the discontinuity jumps of the derivatives of the spline
|
||||
c at the knots. the amount of smoothness of s(u,v) is determined by
|
||||
c the condition that fp = sum((w(i)*(z(i)-s(u(i),v(i))))**2) be <= s,
|
||||
c with s a given non-negative constant.
|
||||
c the bicubic spline is given in its standard b-spline representation
|
||||
c and the corresponding function f(x,y) can be evaluated by means of
|
||||
c function program evapol.
|
||||
c
|
||||
c calling sequence:
|
||||
c call polar(iopt,m,x,y,z,w,rad,s,nuest,nvest,eps,nu,tu,
|
||||
c * nv,tv,u,v,wrk1,lwrk1,wrk2,lwrk2,iwrk,kwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt : integer array of dimension 3, specifying different options.
|
||||
c unchanged on exit.
|
||||
c iopt(1):on entry iopt(1) must specify whether a weighted
|
||||
c least-squares polar spline (iopt(1)=-1) or a smoothing
|
||||
c polar spline (iopt(1)=0 or 1) must be determined.
|
||||
c if iopt(1)=0 the routine will start with an initial set of
|
||||
c knots tu(i)=0,tu(i+4)=1,i=1,...,4;tv(i)=(2*i-9)*pi,i=1,...,8.
|
||||
c if iopt(1)=1 the routine will continue with the set of knots
|
||||
c found at the last call of the routine.
|
||||
c attention: a call with iopt(1)=1 must always be immediately
|
||||
c preceded by another call with iopt(1) = 1 or iopt(1) = 0.
|
||||
c iopt(2):on entry iopt(2) must specify the requested order of conti-
|
||||
c nuity for f(x,y) at the origin.
|
||||
c if iopt(2)=0 only condition (1) must be fulfilled,
|
||||
c if iopt(2)=1 conditions (1)+(2) must be fulfilled and
|
||||
c if iopt(2)=2 conditions (1)+(2)+(3) must be fulfilled.
|
||||
c iopt(3):on entry iopt(3) must specify whether (iopt(3)=1) or not
|
||||
c (iopt(3)=0) the approximation f(x,y) must vanish at the
|
||||
c boundary of the approximation domain.
|
||||
c m : integer. on entry m must specify the number of data points.
|
||||
c m >= 4-iopt(2)-iopt(3) unchanged on exit.
|
||||
c x : real array of dimension at least (m).
|
||||
c y : real array of dimension at least (m).
|
||||
c z : real array of dimension at least (m).
|
||||
c before entry, x(i),y(i),z(i) must be set to the co-ordinates
|
||||
c of the i-th data point, for i=1,...,m. the order of the data
|
||||
c points is immaterial. unchanged on exit.
|
||||
c w : real array of dimension at least (m). before entry, w(i) must
|
||||
c be set to the i-th value in the set of weights. the w(i) must
|
||||
c be strictly positive. unchanged on exit.
|
||||
c rad : real function subprogram defining the boundary of the approx-
|
||||
c imation domain, i.e x = rad(v)*cos(v) , y = rad(v)*sin(v),
|
||||
c -pi <= v <= pi.
|
||||
c must be declared external in the calling (sub)program.
|
||||
c s : real. on entry (in case iopt(1) >=0) s must specify the
|
||||
c smoothing factor. s >=0. unchanged on exit.
|
||||
c for advice on the choice of s see further comments
|
||||
c nuest : integer. unchanged on exit.
|
||||
c nvest : integer. unchanged on exit.
|
||||
c on entry, nuest and nvest must specify an upper bound for the
|
||||
c number of knots required in the u- and v-directions resp.
|
||||
c these numbers will also determine the storage space needed by
|
||||
c the routine. nuest >= 8, nvest >= 8.
|
||||
c in most practical situation nuest = nvest = 8+sqrt(m/2) will
|
||||
c be sufficient. see also further comments.
|
||||
c eps : real.
|
||||
c on entry, eps must specify a threshold for determining the
|
||||
c effective rank of an over-determined linear system of equat-
|
||||
c ions. 0 < eps < 1. if the number of decimal digits in the
|
||||
c computer representation of a real number is q, then 10**(-q)
|
||||
c is a suitable value for eps in most practical applications.
|
||||
c unchanged on exit.
|
||||
c nu : integer.
|
||||
c unless ier=10 (in case iopt(1) >=0),nu will contain the total
|
||||
c number of knots with respect to the u-variable, of the spline
|
||||
c approximation returned. if the computation mode iopt(1)=1
|
||||
c is used, the value of nu should be left unchanged between
|
||||
c subsequent calls.
|
||||
c in case iopt(1)=-1,the value of nu must be specified on entry
|
||||
c tu : real array of dimension at least nuest.
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline with respect to the u-variable, i.e. the position
|
||||
c of the interior knots tu(5),...,tu(nu-4) as well as the
|
||||
c position of the additional knots tu(1)=...=tu(4)=0 and
|
||||
c tu(nu-3)=...=tu(nu)=1 needed for the b-spline representation
|
||||
c if the computation mode iopt(1)=1 is used,the values of
|
||||
c tu(1),...,tu(nu) should be left unchanged between subsequent
|
||||
c calls. if the computation mode iopt(1)=-1 is used,the values
|
||||
c tu(5),...tu(nu-4) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c nv : integer.
|
||||
c unless ier=10 (in case iopt(1)>=0), nv will contain the total
|
||||
c number of knots with respect to the v-variable, of the spline
|
||||
c approximation returned. if the computation mode iopt(1)=1
|
||||
c is used, the value of nv should be left unchanged between
|
||||
c subsequent calls. in case iopt(1)=-1, the value of nv should
|
||||
c be specified on entry.
|
||||
c tv : real array of dimension at least nvest.
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline with respect to the v-variable, i.e. the position of
|
||||
c the interior knots tv(5),...,tv(nv-4) as well as the position
|
||||
c of the additional knots tv(1),...,tv(4) and tv(nv-3),...,
|
||||
c tv(nv) needed for the b-spline representation.
|
||||
c if the computation mode iopt(1)=1 is used, the values of
|
||||
c tv(1),...,tv(nv) should be left unchanged between subsequent
|
||||
c calls. if the computation mode iopt(1)=-1 is used,the values
|
||||
c tv(5),...tv(nv-4) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c u : real array of dimension at least (m).
|
||||
c v : real array of dimension at least (m).
|
||||
c on successful exit, u(i),v(i) contains the co-ordinates of
|
||||
c the i-th data point with respect to the transformed rectan-
|
||||
c gular approximation domain, for i=1,2,...,m.
|
||||
c if the computation mode iopt(1)=1 is used the values of
|
||||
c u(i),v(i) should be left unchanged between subsequent calls.
|
||||
c c : real array of dimension at least (nuest-4)*(nvest-4).
|
||||
c on successful exit, c contains the coefficients of the spline
|
||||
c approximation s(u,v).
|
||||
c fp : real. unless ier=10, fp contains the weighted sum of
|
||||
c squared residuals of the spline approximation returned.
|
||||
c wrk1 : real array of dimension (lwrk1). used as workspace.
|
||||
c if the computation mode iopt(1)=1 is used the value of
|
||||
c wrk1(1) should be left unchanged between subsequent calls.
|
||||
c on exit wrk1(2),wrk1(3),...,wrk1(1+ncof) will contain the
|
||||
c values d(i)/max(d(i)),i=1,...,ncof=1+iopt(2)*(iopt(2)+3)/2+
|
||||
c (nv-7)*(nu-5-iopt(2)-iopt(3)) with d(i) the i-th diagonal el-
|
||||
c ement of the triangular matrix for calculating the b-spline
|
||||
c coefficients.it includes those elements whose square is < eps
|
||||
c which are treated as 0 in the case of rank deficiency(ier=-2)
|
||||
c lwrk1 : integer. on entry lwrk1 must specify the actual dimension of
|
||||
c the array wrk1 as declared in the calling (sub)program.
|
||||
c lwrk1 must not be too small. let
|
||||
c k = nuest-7, l = nvest-7, p = 1+iopt(2)*(iopt(2)+3)/2,
|
||||
c q = k+2-iopt(2)-iopt(3) then
|
||||
c lwrk1 >= 129+10*k+21*l+k*l+(p+l*q)*(1+8*l+p)+8*m
|
||||
c wrk2 : real array of dimension (lwrk2). used as workspace, but
|
||||
c only in the case a rank deficient system is encountered.
|
||||
c lwrk2 : integer. on entry lwrk2 must specify the actual dimension of
|
||||
c the array wrk2 as declared in the calling (sub)program.
|
||||
c lwrk2 > 0 . a save upper bound for lwrk2 = (p+l*q+1)*(4*l+p)
|
||||
c +p+l*q where p,l,q are as above. if there are enough data
|
||||
c points, scattered uniformly over the approximation domain
|
||||
c and if the smoothing factor s is not too small, there is a
|
||||
c good chance that this extra workspace is not needed. a lot
|
||||
c of memory might therefore be saved by setting lwrk2=1.
|
||||
c (see also ier > 10)
|
||||
c iwrk : integer array of dimension (kwrk). used as workspace.
|
||||
c kwrk : integer. on entry kwrk must specify the actual dimension of
|
||||
c the array iwrk as declared in the calling (sub)program.
|
||||
c kwrk >= m+(nuest-7)*(nvest-7).
|
||||
c ier : integer. unless the routine detects an error, ier contains a
|
||||
c non-positive value on exit, i.e.
|
||||
c ier=0 : normal return. the spline returned has a residual sum of
|
||||
c squares fp such that abs(fp-s)/s <= tol with tol a relat-
|
||||
c ive tolerance set to 0.001 by the program.
|
||||
c ier=-1 : normal return. the spline returned is an interpolating
|
||||
c spline (fp=0).
|
||||
c ier=-2 : normal return. the spline returned is the weighted least-
|
||||
c squares constrained polynomial . in this extreme case
|
||||
c fp gives the upper bound for the smoothing factor s.
|
||||
c ier<-2 : warning. the coefficients of the spline returned have been
|
||||
c computed as the minimal norm least-squares solution of a
|
||||
c (numerically) rank deficient system. (-ier) gives the rank.
|
||||
c especially if the rank deficiency which can be computed as
|
||||
c 1+iopt(2)*(iopt(2)+3)/2+(nv-7)*(nu-5-iopt(2)-iopt(3))+ier
|
||||
c is large the results may be inaccurate.
|
||||
c they could also seriously depend on the value of eps.
|
||||
c ier=1 : error. the required storage space exceeds the available
|
||||
c storage space, as specified by the parameters nuest and
|
||||
c nvest.
|
||||
c probably causes : nuest or nvest too small. if these param-
|
||||
c eters are already large, it may also indicate that s is
|
||||
c too small
|
||||
c the approximation returned is the weighted least-squares
|
||||
c polar spline according to the current set of knots.
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=2 : error. a theoretically impossible result was found during
|
||||
c the iteration process for finding a smoothing spline with
|
||||
c fp = s. probably causes : s too small or badly chosen eps.
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=3 : error. the maximal number of iterations maxit (set to 20
|
||||
c by the program) allowed for finding a smoothing spline
|
||||
c with fp=s has been reached. probably causes : s too small
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=4 : error. no more knots can be added because the dimension
|
||||
c of the spline 1+iopt(2)*(iopt(2)+3)/2+(nv-7)*(nu-5-iopt(2)
|
||||
c -iopt(3)) already exceeds the number of data points m.
|
||||
c probably causes : either s or m too small.
|
||||
c the approximation returned is the weighted least-squares
|
||||
c polar spline according to the current set of knots.
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=5 : error. no more knots can be added because the additional
|
||||
c knot would (quasi) coincide with an old one.
|
||||
c probably causes : s too small or too large a weight to an
|
||||
c inaccurate data point.
|
||||
c the approximation returned is the weighted least-squares
|
||||
c polar spline according to the current set of knots.
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=10 : error. on entry, the input data are controlled on validity
|
||||
c the following restrictions must be satisfied.
|
||||
c -1<=iopt(1)<=1 , 0<=iopt(2)<=2 , 0<=iopt(3)<=1 ,
|
||||
c m>=4-iopt(2)-iopt(3) , nuest>=8 ,nvest >=8, 0<eps<1,
|
||||
c 0<=teta(i)<=pi, 0<=phi(i)<=2*pi, w(i)>0, i=1,...,m
|
||||
c lwrk1 >= 129+10*k+21*l+k*l+(p+l*q)*(1+8*l+p)+8*m
|
||||
c kwrk >= m+(nuest-7)*(nvest-7)
|
||||
c if iopt(1)=-1:9<=nu<=nuest,9+iopt(2)*(iopt(2)+1)<=nv<=nvest
|
||||
c 0<tu(5)<tu(6)<...<tu(nu-4)<1
|
||||
c -pi<tv(5)<tv(6)<...<tv(nv-4)<pi
|
||||
c if iopt(1)>=0: s>=0
|
||||
c if one of these conditions is found to be violated,control
|
||||
c is immediately repassed to the calling program. in that
|
||||
c case there is no approximation returned.
|
||||
c ier>10 : error. lwrk2 is too small, i.e. there is not enough work-
|
||||
c space for computing the minimal least-squares solution of
|
||||
c a rank deficient system of linear equations. ier gives the
|
||||
c requested value for lwrk2. there is no approximation re-
|
||||
c turned but, having saved the information contained in nu,
|
||||
c nv,tu,tv,wrk1,u,v and having adjusted the value of lwrk2
|
||||
c and the dimension of the array wrk2 accordingly, the user
|
||||
c can continue at the point the program was left, by calling
|
||||
c polar with iopt(1)=1.
|
||||
c
|
||||
c further comments:
|
||||
c by means of the parameter s, the user can control the tradeoff
|
||||
c between closeness of fit and smoothness of fit of the approximation.
|
||||
c if s is too large, the spline will be too smooth and signal will be
|
||||
c lost ; if s is too small the spline will pick up too much noise. in
|
||||
c the extreme cases the program will return an interpolating spline if
|
||||
c s=0 and the constrained weighted least-squares polynomial if s is
|
||||
c very large. between these extremes, a properly chosen s will result
|
||||
c in a good compromise between closeness of fit and smoothness of fit.
|
||||
c to decide whether an approximation, corresponding to a certain s is
|
||||
c satisfactory the user is highly recommended to inspect the fits
|
||||
c graphically.
|
||||
c recommended values for s depend on the weights w(i). if these are
|
||||
c taken as 1/d(i) with d(i) an estimate of the standard deviation of
|
||||
c z(i), a good s-value should be found in the range (m-sqrt(2*m),m+
|
||||
c sqrt(2*m)). if nothing is known about the statistical error in z(i)
|
||||
c each w(i) can be set equal to one and s determined by trial and
|
||||
c error, taking account of the comments above. the best is then to
|
||||
c start with a very large value of s ( to determine the least-squares
|
||||
c polynomial and the corresponding upper bound fp0 for s) and then to
|
||||
c progressively decrease the value of s ( say by a factor 10 in the
|
||||
c beginning, i.e. s=fp0/10, fp0/100,...and more carefully as the
|
||||
c approximation shows more detail) to obtain closer fits.
|
||||
c to choose s very small is strongly discouraged. this considerably
|
||||
c increases computation time and memory requirements. it may also
|
||||
c cause rank-deficiency (ier<-2) and endager numerical stability.
|
||||
c to economize the search for a good s-value the program provides with
|
||||
c different modes of computation. at the first call of the routine, or
|
||||
c whenever he wants to restart with the initial set of knots the user
|
||||
c must set iopt(1)=0.
|
||||
c if iopt(1)=1 the program will continue with the set of knots found
|
||||
c at the last call of the routine. this will save a lot of computation
|
||||
c time if polar is called repeatedly for different values of s.
|
||||
c the number of knots of the spline returned and their location will
|
||||
c depend on the value of s and on the complexity of the shape of the
|
||||
c function underlying the data. if the computation mode iopt(1)=1
|
||||
c is used, the knots returned may also depend on the s-values at
|
||||
c previous calls (if these were smaller). therefore, if after a number
|
||||
c of trials with different s-values and iopt(1)=1,the user can finally
|
||||
c accept a fit as satisfactory, it may be worthwhile for him to call
|
||||
c polar once more with the selected value for s but now with iopt(1)=0
|
||||
c indeed, polar may then return an approximation of the same quality
|
||||
c of fit but with fewer knots and therefore better if data reduction
|
||||
c is also an important objective for the user.
|
||||
c the number of knots may also depend on the upper bounds nuest and
|
||||
c nvest. indeed, if at a certain stage in polar the number of knots
|
||||
c in one direction (say nu) has reached the value of its upper bound
|
||||
c (nuest), then from that moment on all subsequent knots are added
|
||||
c in the other (v) direction. this may indicate that the value of
|
||||
c nuest is too small. on the other hand, it gives the user the option
|
||||
c of limiting the number of knots the routine locates in any direction
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpback,fpbspl,fppola,fpdisc,fpgivs,fprank,fprati,fprota,fporde,
|
||||
c fprppo
|
||||
c
|
||||
c references:
|
||||
c dierckx p.: an algorithm for fitting data over a circle using tensor
|
||||
c product splines,j.comp.appl.maths 15 (1986) 161-173.
|
||||
c dierckx p.: an algorithm for fitting data on a circle using tensor
|
||||
c product splines, report tw68, dept. computer science,
|
||||
c k.u.leuven, 1984.
|
||||
c dierckx p.: curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u. leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : june 1984
|
||||
c latest update : march 1989
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 s,eps,fp
|
||||
integer m,nuest,nvest,nu,nv,lwrk1,lwrk2,kwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),y(m),z(m),w(m),tu(nuest),tv(nvest),u(m),v(m),
|
||||
* c((nuest-4)*(nvest-4)),wrk1(lwrk1),wrk2(lwrk2)
|
||||
integer iopt(3),iwrk(kwrk)
|
||||
c ..user specified function
|
||||
real*8 rad
|
||||
c ..local scalars..
|
||||
real*8 tol,pi,dist,r,one
|
||||
integer i,ib1,ib3,ki,kn,kwest,la,lbu,lcc,lcs,lro,j,
|
||||
* lbv,lco,lf,lff,lfp,lh,lq,lsu,lsv,lwest,maxit,ncest,ncc,nuu,
|
||||
* nvv,nreg,nrint,nu4,nv4,iopt1,iopt2,iopt3,ipar,nvmin
|
||||
c ..function references..
|
||||
real*8 datan2,sqrt
|
||||
external rad
|
||||
c ..subroutine references..
|
||||
c fppola
|
||||
c ..
|
||||
c set up constants
|
||||
one = 1d0
|
||||
c we set up the parameters tol and maxit.
|
||||
maxit = 20
|
||||
tol = 0.1e-02
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid,control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(eps.le.0. .or. eps.ge.1.) go to 60
|
||||
iopt1 = iopt(1)
|
||||
if(iopt1.lt.(-1) .or. iopt1.gt.1) go to 60
|
||||
iopt2 = iopt(2)
|
||||
if(iopt2.lt.0 .or. iopt2.gt.2) go to 60
|
||||
iopt3 = iopt(3)
|
||||
if(iopt3.lt.0 .or. iopt3.gt.1) go to 60
|
||||
if(m.lt.(4-iopt2-iopt3)) go to 60
|
||||
if(nuest.lt.8 .or. nvest.lt.8) go to 60
|
||||
nu4 = nuest-4
|
||||
nv4 = nvest-4
|
||||
ncest = nu4*nv4
|
||||
nuu = nuest-7
|
||||
nvv = nvest-7
|
||||
ipar = 1+iopt2*(iopt2+3)/2
|
||||
ncc = ipar+nvv*(nuest-5-iopt2-iopt3)
|
||||
nrint = nuu+nvv
|
||||
nreg = nuu*nvv
|
||||
ib1 = 4*nvv
|
||||
ib3 = ib1+ipar
|
||||
lwest = ncc*(1+ib1+ib3)+2*nrint+ncest+m*8+ib3+5*nuest+12*nvest
|
||||
kwest = m+nreg
|
||||
if(lwrk1.lt.lwest .or. kwrk.lt.kwest) go to 60
|
||||
if(iopt1.gt.0) go to 40
|
||||
do 10 i=1,m
|
||||
if(w(i).le.0.) go to 60
|
||||
dist = x(i)**2+y(i)**2
|
||||
u(i) = 0.
|
||||
v(i) = 0.
|
||||
if(dist.le.0.) go to 10
|
||||
v(i) = datan2(y(i),x(i))
|
||||
r = rad(v(i))
|
||||
if(r.le.0.) go to 60
|
||||
u(i) = sqrt(dist)/r
|
||||
if(u(i).gt.one) go to 60
|
||||
10 continue
|
||||
if(iopt1.eq.0) go to 40
|
||||
nuu = nu-8
|
||||
if(nuu.lt.1 .or. nu.gt.nuest) go to 60
|
||||
tu(4) = 0.
|
||||
do 20 i=1,nuu
|
||||
j = i+4
|
||||
if(tu(j).le.tu(j-1) .or. tu(j).ge.one) go to 60
|
||||
20 continue
|
||||
nvv = nv-8
|
||||
nvmin = 9+iopt2*(iopt2+1)
|
||||
if(nv.lt.nvmin .or. nv.gt.nvest) go to 60
|
||||
pi = datan2(0d0,-one)
|
||||
tv(4) = -pi
|
||||
do 30 i=1,nvv
|
||||
j = i+4
|
||||
if(tv(j).le.tv(j-1) .or. tv(j).ge.pi) go to 60
|
||||
30 continue
|
||||
go to 50
|
||||
40 if(s.lt.0.) go to 60
|
||||
50 ier = 0
|
||||
c we partition the working space and determine the spline approximation
|
||||
kn = 1
|
||||
ki = kn+m
|
||||
lq = 2
|
||||
la = lq+ncc*ib3
|
||||
lf = la+ncc*ib1
|
||||
lff = lf+ncc
|
||||
lfp = lff+ncest
|
||||
lco = lfp+nrint
|
||||
lh = lco+nrint
|
||||
lbu = lh+ib3
|
||||
lbv = lbu+5*nuest
|
||||
lro = lbv+5*nvest
|
||||
lcc = lro+nvest
|
||||
lcs = lcc+nvest
|
||||
lsu = lcs+nvest*5
|
||||
lsv = lsu+m*4
|
||||
call fppola(iopt1,iopt2,iopt3,m,u,v,z,w,rad,s,nuest,nvest,eps,tol,
|
||||
*
|
||||
* maxit,ib1,ib3,ncest,ncc,nrint,nreg,nu,tu,nv,tv,c,fp,wrk1(1),
|
||||
* wrk1(lfp),wrk1(lco),wrk1(lf),wrk1(lff),wrk1(lro),wrk1(lcc),
|
||||
* wrk1(lcs),wrk1(la),wrk1(lq),wrk1(lbu),wrk1(lbv),wrk1(lsu),
|
||||
* wrk1(lsv),wrk1(lh),iwrk(ki),iwrk(kn),wrk2,lwrk2,ier)
|
||||
60 return
|
||||
end
|
||||
|
||||
118
cxx/fitpack/profil.f
Normal file
118
cxx/fitpack/profil.f
Normal file
@ -0,0 +1,118 @@
|
||||
recursive subroutine profil(iopt,tx,nx,ty,ny,c,kx,ky,u,nu,cu,ier)
|
||||
implicit none
|
||||
c if iopt=0 subroutine profil calculates the b-spline coefficients of
|
||||
c the univariate spline f(y) = s(u,y) with s(x,y) a bivariate spline of
|
||||
c degrees kx and ky, given in the b-spline representation.
|
||||
c if iopt = 1 it calculates the b-spline coefficients of the univariate
|
||||
c spline g(x) = s(x,u)
|
||||
c
|
||||
c calling sequence:
|
||||
c call profil(iopt,tx,nx,ty,ny,c,kx,ky,u,nu,cu,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c iopt : integer flag, specifying whether the profile f(y) (iopt=0)
|
||||
c or the profile g(x) (iopt=1) must be determined.
|
||||
c tx : real array, length nx, which contains the position of the
|
||||
c knots in the x-direction.
|
||||
c nx : integer, giving the total number of knots in the x-direction
|
||||
c ty : real array, length ny, which contains the position of the
|
||||
c knots in the y-direction.
|
||||
c ny : integer, giving the total number of knots in the y-direction
|
||||
c c : real array, length (nx-kx-1)*(ny-ky-1), which contains the
|
||||
c b-spline coefficients.
|
||||
c kx,ky : integer values, giving the degrees of the spline.
|
||||
c u : real value, specifying the requested profile.
|
||||
c tx(kx+1)<=u<=tx(nx-kx), if iopt=0.
|
||||
c ty(ky+1)<=u<=ty(ny-ky), if iopt=1.
|
||||
c nu : on entry nu must specify the dimension of the array cu.
|
||||
c nu >= ny if iopt=0, nu >= nx if iopt=1.
|
||||
c
|
||||
c output parameters:
|
||||
c cu : real array of dimension (nu).
|
||||
c on successful exit this array contains the b-spline
|
||||
c ier : integer error flag
|
||||
c ier=0 : normal return
|
||||
c ier=10: invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c if iopt=0 : tx(kx+1) <= u <= tx(nx-kx), nu >=ny.
|
||||
c if iopt=1 : ty(ky+1) <= u <= ty(ny-ky), nu >=nx.
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpbspl
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer iopt,nx,ny,kx,ky,nu,ier
|
||||
real*8 u
|
||||
c ..array arguments..
|
||||
real*8 tx(nx),ty(ny),c((nx-kx-1)*(ny-ky-1)),cu(nu)
|
||||
c ..local scalars..
|
||||
integer i,j,kx1,ky1,l,l1,m,m0,nkx1,nky1
|
||||
real*8 sum
|
||||
c ..local array
|
||||
real*8 h(6)
|
||||
c ..
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
kx1 = kx+1
|
||||
ky1 = ky+1
|
||||
nkx1 = nx-kx1
|
||||
nky1 = ny-ky1
|
||||
ier = 10
|
||||
if(iopt.ne.0) go to 200
|
||||
if(nu.lt.ny) go to 300
|
||||
if(u.lt.tx(kx1) .or. u.gt.tx(nkx1+1)) go to 300
|
||||
c the b-splinecoefficients of f(y) = s(u,y).
|
||||
ier = 0
|
||||
l = kx1
|
||||
l1 = l+1
|
||||
110 if(u.lt.tx(l1) .or. l.eq.nkx1) go to 120
|
||||
l = l1
|
||||
l1 = l+1
|
||||
go to 110
|
||||
120 call fpbspl(tx,nx,kx,u,l,h)
|
||||
m0 = (l-kx1)*nky1+1
|
||||
do 140 i=1,nky1
|
||||
m = m0
|
||||
sum = 0.
|
||||
do 130 j=1,kx1
|
||||
sum = sum+h(j)*c(m)
|
||||
m = m+nky1
|
||||
130 continue
|
||||
cu(i) = sum
|
||||
m0 = m0+1
|
||||
140 continue
|
||||
go to 300
|
||||
200 if(nu.lt.nx) go to 300
|
||||
if(u.lt.ty(ky1) .or. u.gt.ty(nky1+1)) go to 300
|
||||
c the b-splinecoefficients of g(x) = s(x,u).
|
||||
ier = 0
|
||||
l = ky1
|
||||
l1 = l+1
|
||||
210 if(u.lt.ty(l1) .or. l.eq.nky1) go to 220
|
||||
l = l1
|
||||
l1 = l+1
|
||||
go to 210
|
||||
220 call fpbspl(ty,ny,ky,u,l,h)
|
||||
m0 = l-ky
|
||||
do 240 i=1,nkx1
|
||||
m = m0
|
||||
sum = 0.
|
||||
do 230 j=1,ky1
|
||||
sum = sum+h(j)*c(m)
|
||||
m = m+1
|
||||
230 continue
|
||||
cu(i) = sum
|
||||
m0 = m0+nky1
|
||||
240 continue
|
||||
300 return
|
||||
end
|
||||
|
||||
354
cxx/fitpack/regrid.f
Normal file
354
cxx/fitpack/regrid.f
Normal file
@ -0,0 +1,354 @@
|
||||
recursive subroutine regrid(iopt,mx,x,my,y,z,xb,xe,yb,ye,kx,ky,s,
|
||||
* nxest,nyest,nx,tx,ny,ty,c,fp,wrk,lwrk,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c given the set of values z(i,j) on the rectangular grid (x(i),y(j)),
|
||||
c i=1,...,mx;j=1,...,my, subroutine regrid determines a smooth bivar-
|
||||
c iate spline approximation s(x,y) of degrees kx and ky on the rect-
|
||||
c angle xb <= x <= xe, yb <= y <= ye.
|
||||
c if iopt = -1 regrid calculates the least-squares spline according
|
||||
c to a given set of knots.
|
||||
c if iopt >= 0 the total numbers nx and ny of these knots and their
|
||||
c position tx(j),j=1,...,nx and ty(j),j=1,...,ny are chosen automatic-
|
||||
c ally by the routine. the smoothness of s(x,y) is then achieved by
|
||||
c minimalizing the discontinuity jumps in the derivatives of s(x,y)
|
||||
c across the boundaries of the subpanels (tx(i),tx(i+1))*(ty(j),ty(j+1).
|
||||
c the amounth of smoothness is determined by the condition that f(p) =
|
||||
c sum ((z(i,j)-s(x(i),y(j))))**2) be <= s, with s a given non-negative
|
||||
c constant, called the smoothing factor.
|
||||
c the fit is given in the b-spline representation (b-spline coefficients
|
||||
c c((ny-ky-1)*(i-1)+j),i=1,...,nx-kx-1;j=1,...,ny-ky-1) and can be eval-
|
||||
c uated by means of subroutine bispev.
|
||||
c
|
||||
c calling sequence:
|
||||
c call regrid(iopt,mx,x,my,y,z,xb,xe,yb,ye,kx,ky,s,nxest,nyest,
|
||||
c * nx,tx,ny,ty,c,fp,wrk,lwrk,iwrk,kwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt : integer flag. on entry iopt must specify whether a least-
|
||||
c squares spline (iopt=-1) or a smoothing spline (iopt=0 or 1)
|
||||
c must be determined.
|
||||
c if iopt=0 the routine will start with an initial set of knots
|
||||
c tx(i)=xb,tx(i+kx+1)=xe,i=1,...,kx+1;ty(i)=yb,ty(i+ky+1)=ye,i=
|
||||
c 1,...,ky+1. if iopt=1 the routine will continue with the set
|
||||
c of knots found at the last call of the routine.
|
||||
c attention: a call with iopt=1 must always be immediately pre-
|
||||
c ceded by another call with iopt=1 or iopt=0 and
|
||||
c s.ne.0.
|
||||
c unchanged on exit.
|
||||
c mx : integer. on entry mx must specify the number of grid points
|
||||
c along the x-axis. mx > kx . unchanged on exit.
|
||||
c x : real array of dimension at least (mx). before entry, x(i)
|
||||
c must be set to the x-co-ordinate of the i-th grid point
|
||||
c along the x-axis, for i=1,2,...,mx. these values must be
|
||||
c supplied in strictly ascending order. unchanged on exit.
|
||||
c my : integer. on entry my must specify the number of grid points
|
||||
c along the y-axis. my > ky . unchanged on exit.
|
||||
c y : real array of dimension at least (my). before entry, y(j)
|
||||
c must be set to the y-co-ordinate of the j-th grid point
|
||||
c along the y-axis, for j=1,2,...,my. these values must be
|
||||
c supplied in strictly ascending order. unchanged on exit.
|
||||
c z : real array of dimension at least (mx*my).
|
||||
c before entry, z(my*(i-1)+j) must be set to the data value at
|
||||
c the grid point (x(i),y(j)) for i=1,...,mx and j=1,...,my.
|
||||
c unchanged on exit.
|
||||
c xb,xe : real values. on entry xb,xe,yb and ye must specify the bound-
|
||||
c yb,ye aries of the rectangular approximation domain.
|
||||
c xb<=x(i)<=xe,i=1,...,mx; yb<=y(j)<=ye,j=1,...,my.
|
||||
c unchanged on exit.
|
||||
c kx,ky : integer values. on entry kx and ky must specify the degrees
|
||||
c of the spline. 1<=kx,ky<=5. it is recommended to use bicubic
|
||||
c (kx=ky=3) splines. unchanged on exit.
|
||||
c s : real. on entry (in case iopt>=0) s must specify the smoothing
|
||||
c factor. s >=0. unchanged on exit.
|
||||
c for advice on the choice of s see further comments
|
||||
c nxest : integer. unchanged on exit.
|
||||
c nyest : integer. unchanged on exit.
|
||||
c on entry, nxest and nyest must specify an upper bound for the
|
||||
c number of knots required in the x- and y-directions respect.
|
||||
c these numbers will also determine the storage space needed by
|
||||
c the routine. nxest >= 2*(kx+1), nyest >= 2*(ky+1).
|
||||
c in most practical situation nxest = mx/2, nyest=my/2, will
|
||||
c be sufficient. always large enough are nxest=mx+kx+1, nyest=
|
||||
c my+ky+1, the number of knots needed for interpolation (s=0).
|
||||
c see also further comments.
|
||||
c nx : integer.
|
||||
c unless ier=10 (in case iopt >=0), nx will contain the total
|
||||
c number of knots with respect to the x-variable, of the spline
|
||||
c approximation returned. if the computation mode iopt=1 is
|
||||
c used, the value of nx should be left unchanged between sub-
|
||||
c sequent calls.
|
||||
c in case iopt=-1, the value of nx should be specified on entry
|
||||
c tx : real array of dimension nmax.
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline with respect to the x-variable, i.e. the position of
|
||||
c the interior knots tx(kx+2),...,tx(nx-kx-1) as well as the
|
||||
c position of the additional knots tx(1)=...=tx(kx+1)=xb and
|
||||
c tx(nx-kx)=...=tx(nx)=xe needed for the b-spline representat.
|
||||
c if the computation mode iopt=1 is used, the values of tx(1),
|
||||
c ...,tx(nx) should be left unchanged between subsequent calls.
|
||||
c if the computation mode iopt=-1 is used, the values tx(kx+2),
|
||||
c ...tx(nx-kx-1) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c ny : integer.
|
||||
c unless ier=10 (in case iopt >=0), ny will contain the total
|
||||
c number of knots with respect to the y-variable, of the spline
|
||||
c approximation returned. if the computation mode iopt=1 is
|
||||
c used, the value of ny should be left unchanged between sub-
|
||||
c sequent calls.
|
||||
c in case iopt=-1, the value of ny should be specified on entry
|
||||
c ty : real array of dimension nmax.
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline with respect to the y-variable, i.e. the position of
|
||||
c the interior knots ty(ky+2),...,ty(ny-ky-1) as well as the
|
||||
c position of the additional knots ty(1)=...=ty(ky+1)=yb and
|
||||
c ty(ny-ky)=...=ty(ny)=ye needed for the b-spline representat.
|
||||
c if the computation mode iopt=1 is used, the values of ty(1),
|
||||
c ...,ty(ny) should be left unchanged between subsequent calls.
|
||||
c if the computation mode iopt=-1 is used, the values ty(ky+2),
|
||||
c ...ty(ny-ky-1) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c c : real array of dimension at least (nxest-kx-1)*(nyest-ky-1).
|
||||
c on successful exit, c contains the coefficients of the spline
|
||||
c approximation s(x,y)
|
||||
c fp : real. unless ier=10, fp contains the sum of squared
|
||||
c residuals of the spline approximation returned.
|
||||
c wrk : real array of dimension (lwrk). used as workspace.
|
||||
c if the computation mode iopt=1 is used the values of wrk(1),
|
||||
c ...,wrk(4) should be left unchanged between subsequent calls.
|
||||
c lwrk : integer. on entry lwrk must specify the actual dimension of
|
||||
c the array wrk as declared in the calling (sub)program.
|
||||
c lwrk must not be too small.
|
||||
c lwrk >= 4+nxest*(my+2*kx+5)+nyest*(2*ky+5)+mx*(kx+1)+
|
||||
c my*(ky+1) +u
|
||||
c where u is the larger of my and nxest.
|
||||
c iwrk : integer array of dimension (kwrk). used as workspace.
|
||||
c if the computation mode iopt=1 is used the values of iwrk(1),
|
||||
c ...,iwrk(3) should be left unchanged between subsequent calls
|
||||
c kwrk : integer. on entry kwrk must specify the actual dimension of
|
||||
c the array iwrk as declared in the calling (sub)program.
|
||||
c kwrk >= 3+mx+my+nxest+nyest.
|
||||
c ier : integer. unless the routine detects an error, ier contains a
|
||||
c non-positive value on exit, i.e.
|
||||
c ier=0 : normal return. the spline returned has a residual sum of
|
||||
c squares fp such that abs(fp-s)/s <= tol with tol a relat-
|
||||
c ive tolerance set to 0.001 by the program.
|
||||
c ier=-1 : normal return. the spline returned is an interpolating
|
||||
c spline (fp=0).
|
||||
c ier=-2 : normal return. the spline returned is the least-squares
|
||||
c polynomial of degrees kx and ky. in this extreme case fp
|
||||
c gives the upper bound for the smoothing factor s.
|
||||
c ier=1 : error. the required storage space exceeds the available
|
||||
c storage space, as specified by the parameters nxest and
|
||||
c nyest.
|
||||
c probably causes : nxest or nyest too small. if these param-
|
||||
c eters are already large, it may also indicate that s is
|
||||
c too small
|
||||
c the approximation returned is the least-squares spline
|
||||
c according to the current set of knots. the parameter fp
|
||||
c gives the corresponding sum of squared residuals (fp>s).
|
||||
c ier=2 : error. a theoretically impossible result was found during
|
||||
c the iteration process for finding a smoothing spline with
|
||||
c fp = s. probably causes : s too small.
|
||||
c there is an approximation returned but the corresponding
|
||||
c sum of squared residuals does not satisfy the condition
|
||||
c abs(fp-s)/s < tol.
|
||||
c ier=3 : error. the maximal number of iterations maxit (set to 20
|
||||
c by the program) allowed for finding a smoothing spline
|
||||
c with fp=s has been reached. probably causes : s too small
|
||||
c there is an approximation returned but the corresponding
|
||||
c sum of squared residuals does not satisfy the condition
|
||||
c abs(fp-s)/s < tol.
|
||||
c ier=10 : error. on entry, the input data are controlled on validity
|
||||
c the following restrictions must be satisfied.
|
||||
c -1<=iopt<=1, 1<=kx,ky<=5, mx>kx, my>ky, nxest>=2*kx+2,
|
||||
c nyest>=2*ky+2, kwrk>=3+mx+my+nxest+nyest,
|
||||
c lwrk >= 4+nxest*(my+2*kx+5)+nyest*(2*ky+5)+mx*(kx+1)+
|
||||
c my*(ky+1) +max(my,nxest),
|
||||
c xb<=x(i-1)<x(i)<=xe,i=2,..,mx,yb<=y(j-1)<y(j)<=ye,j=2,..,my
|
||||
c if iopt=-1: 2*kx+2<=nx<=min(nxest,mx+kx+1)
|
||||
c xb<tx(kx+2)<tx(kx+3)<...<tx(nx-kx-1)<xe
|
||||
c 2*ky+2<=ny<=min(nyest,my+ky+1)
|
||||
c yb<ty(ky+2)<ty(ky+3)<...<ty(ny-ky-1)<ye
|
||||
c the schoenberg-whitney conditions, i.e. there must
|
||||
c be subset of grid co-ordinates xx(p) and yy(q) such
|
||||
c that tx(p) < xx(p) < tx(p+kx+1) ,p=1,...,nx-kx-1
|
||||
c ty(q) < yy(q) < ty(q+ky+1) ,q=1,...,ny-ky-1
|
||||
c if iopt>=0: s>=0
|
||||
c if s=0 : nxest>=mx+kx+1, nyest>=my+ky+1
|
||||
c if one of these conditions is found to be violated,control
|
||||
c is immediately repassed to the calling program. in that
|
||||
c case there is no approximation returned.
|
||||
c
|
||||
c further comments:
|
||||
c regrid does not allow individual weighting of the data-values.
|
||||
c so, if these were determined to widely different accuracies, then
|
||||
c perhaps the general data set routine surfit should rather be used
|
||||
c in spite of efficiency.
|
||||
c by means of the parameter s, the user can control the tradeoff
|
||||
c between closeness of fit and smoothness of fit of the approximation.
|
||||
c if s is too large, the spline will be too smooth and signal will be
|
||||
c lost ; if s is too small the spline will pick up too much noise. in
|
||||
c the extreme cases the program will return an interpolating spline if
|
||||
c s=0 and the least-squares polynomial (degrees kx,ky) if s is
|
||||
c very large. between these extremes, a properly chosen s will result
|
||||
c in a good compromise between closeness of fit and smoothness of fit.
|
||||
c to decide whether an approximation, corresponding to a certain s is
|
||||
c satisfactory the user is highly recommended to inspect the fits
|
||||
c graphically.
|
||||
c recommended values for s depend on the accuracy of the data values.
|
||||
c if the user has an idea of the statistical errors on the data, he
|
||||
c can also find a proper estimate for s. for, by assuming that, if he
|
||||
c specifies the right s, regrid will return a spline s(x,y) which
|
||||
c exactly reproduces the function underlying the data he can evaluate
|
||||
c the sum((z(i,j)-s(x(i),y(j)))**2) to find a good estimate for this s
|
||||
c for example, if he knows that the statistical errors on his z(i,j)-
|
||||
c values is not greater than 0.1, he may expect that a good s should
|
||||
c have a value not larger than mx*my*(0.1)**2.
|
||||
c if nothing is known about the statistical error in z(i,j), s must
|
||||
c be determined by trial and error, taking account of the comments
|
||||
c above. the best is then to start with a very large value of s (to
|
||||
c determine the least-squares polynomial and the corresponding upper
|
||||
c bound fp0 for s) and then to progressively decrease the value of s
|
||||
c ( say by a factor 10 in the beginning, i.e. s=fp0/10,fp0/100,...
|
||||
c and more carefully as the approximation shows more detail) to
|
||||
c obtain closer fits.
|
||||
c to economize the search for a good s-value the program provides with
|
||||
c different modes of computation. at the first call of the routine, or
|
||||
c whenever he wants to restart with the initial set of knots the user
|
||||
c must set iopt=0.
|
||||
c if iopt=1 the program will continue with the set of knots found at
|
||||
c the last call of the routine. this will save a lot of computation
|
||||
c time if regrid is called repeatedly for different values of s.
|
||||
c the number of knots of the spline returned and their location will
|
||||
c depend on the value of s and on the complexity of the shape of the
|
||||
c function underlying the data. if the computation mode iopt=1
|
||||
c is used, the knots returned may also depend on the s-values at
|
||||
c previous calls (if these were smaller). therefore, if after a number
|
||||
c of trials with different s-values and iopt=1, the user can finally
|
||||
c accept a fit as satisfactory, it may be worthwhile for him to call
|
||||
c regrid once more with the selected value for s but now with iopt=0.
|
||||
c indeed, regrid may then return an approximation of the same quality
|
||||
c of fit but with fewer knots and therefore better if data reduction
|
||||
c is also an important objective for the user.
|
||||
c the number of knots may also depend on the upper bounds nxest and
|
||||
c nyest. indeed, if at a certain stage in regrid the number of knots
|
||||
c in one direction (say nx) has reached the value of its upper bound
|
||||
c (nxest), then from that moment on all subsequent knots are added
|
||||
c in the other (y) direction. this may indicate that the value of
|
||||
c nxest is too small. on the other hand, it gives the user the option
|
||||
c of limiting the number of knots the routine locates in any direction
|
||||
c for example, by setting nxest=2*kx+2 (the lowest allowable value for
|
||||
c nxest), the user can indicate that he wants an approximation which
|
||||
c is a simple polynomial of degree kx in the variable x.
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpback,fpbspl,fpregr,fpdisc,fpgivs,fpgrre,fprati,fprota,fpchec,
|
||||
c fpknot
|
||||
c
|
||||
c references:
|
||||
c dierckx p. : a fast algorithm for smoothing data on a rectangular
|
||||
c grid while using spline functions, siam j.numer.anal.
|
||||
c 19 (1982) 1286-1304.
|
||||
c dierckx p. : a fast algorithm for smoothing data on a rectangular
|
||||
c grid while using spline functions, report tw53, dept.
|
||||
c computer science,k.u.leuven, 1980.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u. leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : may 1979
|
||||
c latest update : march 1989
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 xb,xe,yb,ye,s,fp
|
||||
integer iopt,mx,my,kx,ky,nxest,nyest,nx,ny,lwrk,kwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 x(mx),y(my),z(mx*my),tx(nxest),ty(nyest),
|
||||
* c((nxest-kx-1)*(nyest-ky-1)),wrk(lwrk)
|
||||
integer iwrk(kwrk)
|
||||
c ..local scalars..
|
||||
real*8 tol
|
||||
integer i,j,jwrk,kndx,kndy,knrx,knry,kwest,kx1,kx2,ky1,ky2,
|
||||
* lfpx,lfpy,lwest,lww,maxit,nc,nminx,nminy,mz
|
||||
c ..function references..
|
||||
integer max0
|
||||
c ..subroutine references..
|
||||
c fpregr,fpchec
|
||||
c ..
|
||||
c we set up the parameters tol and maxit.
|
||||
maxit = 20
|
||||
tol = 0.1e-02
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(kx.le.0 .or. kx.gt.5) go to 70
|
||||
kx1 = kx+1
|
||||
kx2 = kx1+1
|
||||
if(ky.le.0 .or. ky.gt.5) go to 70
|
||||
ky1 = ky+1
|
||||
ky2 = ky1+1
|
||||
if(iopt.lt.(-1) .or. iopt.gt.1) go to 70
|
||||
nminx = 2*kx1
|
||||
if(mx.lt.kx1 .or. nxest.lt.nminx) go to 70
|
||||
nminy = 2*ky1
|
||||
if(my.lt.ky1 .or. nyest.lt.nminy) go to 70
|
||||
mz = mx*my
|
||||
nc = (nxest-kx1)*(nyest-ky1)
|
||||
lwest = 4+nxest*(my+2*kx2+1)+nyest*(2*ky2+1)+mx*kx1+
|
||||
* my*ky1+max0(nxest,my)
|
||||
kwest = 3+mx+my+nxest+nyest
|
||||
if(lwrk.lt.lwest .or. kwrk.lt.kwest) go to 70
|
||||
if(xb.gt.x(1) .or. xe.lt.x(mx)) go to 70
|
||||
do 10 i=2,mx
|
||||
if(x(i-1).ge.x(i)) go to 70
|
||||
10 continue
|
||||
if(yb.gt.y(1) .or. ye.lt.y(my)) go to 70
|
||||
do 20 i=2,my
|
||||
if(y(i-1).ge.y(i)) go to 70
|
||||
20 continue
|
||||
if(iopt.ge.0) go to 50
|
||||
if(nx.lt.nminx .or. nx.gt.nxest) go to 70
|
||||
j = nx
|
||||
do 30 i=1,kx1
|
||||
tx(i) = xb
|
||||
tx(j) = xe
|
||||
j = j-1
|
||||
30 continue
|
||||
call fpchec(x,mx,tx,nx,kx,ier)
|
||||
if(ier.ne.0) go to 70
|
||||
if(ny.lt.nminy .or. ny.gt.nyest) go to 70
|
||||
j = ny
|
||||
do 40 i=1,ky1
|
||||
ty(i) = yb
|
||||
ty(j) = ye
|
||||
j = j-1
|
||||
40 continue
|
||||
call fpchec(y,my,ty,ny,ky,ier)
|
||||
if (ier.eq.0) go to 60
|
||||
go to 70
|
||||
50 if(s.lt.0.) go to 70
|
||||
if(s.eq.0. .and. (nxest.lt.(mx+kx1) .or. nyest.lt.(my+ky1)) )
|
||||
* go to 70
|
||||
ier = 0
|
||||
c we partition the working space and determine the spline approximation
|
||||
60 lfpx = 5
|
||||
lfpy = lfpx+nxest
|
||||
lww = lfpy+nyest
|
||||
jwrk = lwrk-4-nxest-nyest
|
||||
knrx = 4
|
||||
knry = knrx+mx
|
||||
kndx = knry+my
|
||||
kndy = kndx+nxest
|
||||
call fpregr(iopt,x,mx,y,my,z,mz,xb,xe,yb,ye,kx,ky,s,nxest,nyest,
|
||||
* tol,maxit,nc,nx,tx,ny,ty,c,fp,wrk(1),wrk(2),wrk(3),wrk(4),
|
||||
* wrk(lfpx),wrk(lfpy),iwrk(1),iwrk(2),iwrk(3),iwrk(knrx),
|
||||
* iwrk(knry),iwrk(kndx),iwrk(kndy),wrk(lww),jwrk,ier)
|
||||
70 return
|
||||
end
|
||||
|
||||
75
cxx/fitpack/spalde.f
Normal file
75
cxx/fitpack/spalde.f
Normal file
@ -0,0 +1,75 @@
|
||||
recursive subroutine spalde(t,n,c,nc,k1,x,d,ier)
|
||||
implicit none
|
||||
c subroutine spalde evaluates at a point x all the derivatives
|
||||
c (j-1)
|
||||
c d(j) = s (x) , j=1,2,...,k1
|
||||
c of a spline s(x) of order k1 (degree k=k1-1), given in its b-spline
|
||||
c representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c call spalde(t,n,c,k1,x,d,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c t : array,length n, which contains the position of the knots.
|
||||
c n : integer, giving the total number of knots of s(x).
|
||||
c c : array,length nc, which contains the b-spline coefficients.
|
||||
c nc : integer, giving the total number of coefficients (must be >= n-k1)
|
||||
c k1 : integer, giving the order of s(x) (order=degree+1)
|
||||
c x : real, which contains the point where the derivatives must
|
||||
c be evaluated.
|
||||
c
|
||||
c output parameters:
|
||||
c d : array,length k1, containing the derivative values of s(x).
|
||||
c ier : error flag
|
||||
c ier = 0 : normal return
|
||||
c ier =10 : invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c t(k1) <= x <= t(n-k1+1)
|
||||
c
|
||||
c further comments:
|
||||
c if x coincides with a knot, right derivatives are computed
|
||||
c ( left derivatives if x = t(n-k1+1) ).
|
||||
c
|
||||
c other subroutines required: fpader.
|
||||
c
|
||||
c references :
|
||||
c de boor c : on calculating with b-splines, j. approximation theory
|
||||
c 6 (1972) 50-62.
|
||||
c cox m.g. : the numerical evaluation of b-splines, j. inst. maths
|
||||
c applics 10 (1972) 134-149.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer n,nc,k1,ier
|
||||
real*8 x
|
||||
c ..array arguments..
|
||||
real*8 t(n),c(nc),d(k1)
|
||||
c ..local scalars..
|
||||
integer l,nk1
|
||||
c ..
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
nk1 = n-k1
|
||||
if(x.lt.t(k1) .or. x.gt.t(nk1+1)) go to 300
|
||||
c search for knot interval t(l) <= x < t(l+1)
|
||||
l = k1
|
||||
100 if(x.lt.t(l+1) .or. l.eq.nk1) go to 200
|
||||
l = l+1
|
||||
go to 100
|
||||
200 if(t(l).ge.t(l+1)) go to 300
|
||||
ier = 0
|
||||
c calculate the derivatives.
|
||||
call fpader(t,n,c,k1,x,l,d)
|
||||
300 return
|
||||
end
|
||||
502
cxx/fitpack/spgrid.f
Normal file
502
cxx/fitpack/spgrid.f
Normal file
@ -0,0 +1,502 @@
|
||||
recursive subroutine spgrid(iopt,ider,mu,u,mv,v,r,r0,r1,s,
|
||||
* nuest,nvest,nu,tu,nv,tv,c,fp,wrk,lwrk,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c given the function values r(i,j) on the latitude-longitude grid
|
||||
c (u(i),v(j)), i=1,...,mu ; j=1,...,mv , spgrid determines a smooth
|
||||
c bicubic spline approximation on the rectangular domain 0<=u<=pi,
|
||||
c vb<=v<=ve (vb = v(1), ve=vb+2*pi).
|
||||
c this approximation s(u,v) will satisfy the properties
|
||||
c
|
||||
c (1) s(0,v) = s(0,0) = dr(1)
|
||||
c
|
||||
c d s(0,v) d s(0,0) d s(0,pi/2)
|
||||
c (2) -------- = cos(v)* -------- + sin(v)* -----------
|
||||
c d u d u d u
|
||||
c
|
||||
c = cos(v)*dr(2)+sin(v)*dr(3)
|
||||
c vb <= v <= ve
|
||||
c (3) s(pi,v) = s(pi,0) = dr(4)
|
||||
c
|
||||
c d s(pi,v) d s(pi,0) d s(pi,pi/2)
|
||||
c (4) -------- = cos(v)* --------- + sin(v)* ------------
|
||||
c d u d u d u
|
||||
c
|
||||
c = cos(v)*dr(5)+sin(v)*dr(6)
|
||||
c
|
||||
c and will be periodic in the variable v, i.e.
|
||||
c
|
||||
c j j
|
||||
c d s(u,vb) d s(u,ve)
|
||||
c (5) --------- = --------- 0 <=u<= pi , j=0,1,2
|
||||
c j j
|
||||
c d v d v
|
||||
c
|
||||
c the number of knots of s(u,v) and their position tu(i),i=1,2,...,nu;
|
||||
c tv(j),j=1,2,...,nv, is chosen automatically by the routine. the
|
||||
c smoothness of s(u,v) is achieved by minimalizing the discontinuity
|
||||
c jumps of the derivatives of the spline at the knots. the amount of
|
||||
c smoothness of s(u,v) is determined by the condition that
|
||||
c fp=sumi=1,mu(sumj=1,mv((r(i,j)-s(u(i),v(j)))**2))+(r0-s(0,v))**2
|
||||
c + (r1-s(pi,v))**2 <= s, with s a given non-negative constant.
|
||||
c the fit s(u,v) is given in its b-spline representation and can be
|
||||
c evaluated by means of routine bispev
|
||||
c
|
||||
c calling sequence:
|
||||
c call spgrid(iopt,ider,mu,u,mv,v,r,r0,r1,s,nuest,nvest,nu,tu,
|
||||
c * ,nv,tv,c,fp,wrk,lwrk,iwrk,kwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt : integer array of dimension 3, specifying different options.
|
||||
c unchanged on exit.
|
||||
c iopt(1):on entry iopt(1) must specify whether a least-squares spline
|
||||
c (iopt(1)=-1) or a smoothing spline (iopt(1)=0 or 1) must be
|
||||
c determined.
|
||||
c if iopt(1)=0 the routine will start with an initial set of
|
||||
c knots tu(i)=0,tu(i+4)=pi,i=1,...,4;tv(i)=v(1)+(i-4)*2*pi,
|
||||
c i=1,...,8.
|
||||
c if iopt(1)=1 the routine will continue with the set of knots
|
||||
c found at the last call of the routine.
|
||||
c attention: a call with iopt(1)=1 must always be immediately
|
||||
c preceded by another call with iopt(1) = 1 or iopt(1) = 0.
|
||||
c iopt(2):on entry iopt(2) must specify the requested order of conti-
|
||||
c nuity at the pole u=0.
|
||||
c if iopt(2)=0 only condition (1) must be fulfilled and
|
||||
c if iopt(2)=1 conditions (1)+(2) must be fulfilled.
|
||||
c iopt(3):on entry iopt(3) must specify the requested order of conti-
|
||||
c nuity at the pole u=pi.
|
||||
c if iopt(3)=0 only condition (3) must be fulfilled and
|
||||
c if iopt(3)=1 conditions (3)+(4) must be fulfilled.
|
||||
c ider : integer array of dimension 4, specifying different options.
|
||||
c unchanged on exit.
|
||||
c ider(1):on entry ider(1) must specify whether (ider(1)=0 or 1) or not
|
||||
c (ider(1)=-1) there is a data value r0 at the pole u=0.
|
||||
c if ider(1)=1, r0 will be considered to be the right function
|
||||
c value, and it will be fitted exactly (s(0,v)=r0).
|
||||
c if ider(1)=0, r0 will be considered to be a data value just
|
||||
c like the other data values r(i,j).
|
||||
c ider(2):on entry ider(2) must specify whether (ider(2)=1) or not
|
||||
c (ider(2)=0) the approximation has vanishing derivatives
|
||||
c dr(2) and dr(3) at the pole u=0 (in case iopt(2)=1)
|
||||
c ider(3):on entry ider(3) must specify whether (ider(3)=0 or 1) or not
|
||||
c (ider(3)=-1) there is a data value r1 at the pole u=pi.
|
||||
c if ider(3)=1, r1 will be considered to be the right function
|
||||
c value, and it will be fitted exactly (s(pi,v)=r1).
|
||||
c if ider(3)=0, r1 will be considered to be a data value just
|
||||
c like the other data values r(i,j).
|
||||
c ider(4):on entry ider(4) must specify whether (ider(4)=1) or not
|
||||
c (ider(4)=0) the approximation has vanishing derivatives
|
||||
c dr(5) and dr(6) at the pole u=pi (in case iopt(3)=1)
|
||||
c mu : integer. on entry mu must specify the number of grid points
|
||||
c along the u-axis. unchanged on exit.
|
||||
c mu >= 1, mu >=mumin=4-i0-i1-ider(2)-ider(4) with
|
||||
c i0=min(1,ider(1)+1), i1=min(1,ider(3)+1)
|
||||
c u : real array of dimension at least (mu). before entry, u(i)
|
||||
c must be set to the u-co-ordinate of the i-th grid point
|
||||
c along the u-axis, for i=1,2,...,mu. these values must be
|
||||
c supplied in strictly ascending order. unchanged on exit.
|
||||
c 0 < u(i) < pi.
|
||||
c mv : integer. on entry mv must specify the number of grid points
|
||||
c along the v-axis. mv > 3 . unchanged on exit.
|
||||
c v : real array of dimension at least (mv). before entry, v(j)
|
||||
c must be set to the v-co-ordinate of the j-th grid point
|
||||
c along the v-axis, for j=1,2,...,mv. these values must be
|
||||
c supplied in strictly ascending order. unchanged on exit.
|
||||
c -pi <= v(1) < pi , v(mv) < v(1)+2*pi.
|
||||
c r : real array of dimension at least (mu*mv).
|
||||
c before entry, r(mv*(i-1)+j) must be set to the data value at
|
||||
c the grid point (u(i),v(j)) for i=1,...,mu and j=1,...,mv.
|
||||
c unchanged on exit.
|
||||
c r0 : real value. on entry (if ider(1) >=0 ) r0 must specify the
|
||||
c data value at the pole u=0. unchanged on exit.
|
||||
c r1 : real value. on entry (if ider(1) >=0 ) r1 must specify the
|
||||
c data value at the pole u=pi. unchanged on exit.
|
||||
c s : real. on entry (if iopt(1)>=0) s must specify the smoothing
|
||||
c factor. s >=0. unchanged on exit.
|
||||
c for advice on the choice of s see further comments
|
||||
c nuest : integer. unchanged on exit.
|
||||
c nvest : integer. unchanged on exit.
|
||||
c on entry, nuest and nvest must specify an upper bound for the
|
||||
c number of knots required in the u- and v-directions respect.
|
||||
c these numbers will also determine the storage space needed by
|
||||
c the routine. nuest >= 8, nvest >= 8.
|
||||
c in most practical situation nuest = mu/2, nvest=mv/2, will
|
||||
c be sufficient. always large enough are nuest=mu+6+iopt(2)+
|
||||
c iopt(3), nvest = mv+7, the number of knots needed for
|
||||
c interpolation (s=0). see also further comments.
|
||||
c nu : integer.
|
||||
c unless ier=10 (in case iopt(1)>=0), nu will contain the total
|
||||
c number of knots with respect to the u-variable, of the spline
|
||||
c approximation returned. if the computation mode iopt(1)=1 is
|
||||
c used, the value of nu should be left unchanged between sub-
|
||||
c sequent calls. in case iopt(1)=-1, the value of nu should be
|
||||
c specified on entry.
|
||||
c tu : real array of dimension at least (nuest).
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline with respect to the u-variable, i.e. the position of
|
||||
c the interior knots tu(5),...,tu(nu-4) as well as the position
|
||||
c of the additional knots tu(1)=...=tu(4)=0 and tu(nu-3)=...=
|
||||
c tu(nu)=pi needed for the b-spline representation.
|
||||
c if the computation mode iopt(1)=1 is used,the values of tu(1)
|
||||
c ...,tu(nu) should be left unchanged between subsequent calls.
|
||||
c if the computation mode iopt(1)=-1 is used, the values tu(5),
|
||||
c ...tu(nu-4) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c nv : integer.
|
||||
c unless ier=10 (in case iopt(1)>=0), nv will contain the total
|
||||
c number of knots with respect to the v-variable, of the spline
|
||||
c approximation returned. if the computation mode iopt(1)=1 is
|
||||
c used, the value of nv should be left unchanged between sub-
|
||||
c sequent calls. in case iopt(1) = -1, the value of nv should
|
||||
c be specified on entry.
|
||||
c tv : real array of dimension at least (nvest).
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline with respect to the v-variable, i.e. the position of
|
||||
c the interior knots tv(5),...,tv(nv-4) as well as the position
|
||||
c of the additional knots tv(1),...,tv(4) and tv(nv-3),...,
|
||||
c tv(nv) needed for the b-spline representation.
|
||||
c if the computation mode iopt(1)=1 is used,the values of tv(1)
|
||||
c ...,tv(nv) should be left unchanged between subsequent calls.
|
||||
c if the computation mode iopt(1)=-1 is used, the values tv(5),
|
||||
c ...tv(nv-4) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c c : real array of dimension at least (nuest-4)*(nvest-4).
|
||||
c on successful exit, c contains the coefficients of the spline
|
||||
c approximation s(u,v)
|
||||
c fp : real. unless ier=10, fp contains the sum of squared
|
||||
c residuals of the spline approximation returned.
|
||||
c wrk : real array of dimension (lwrk). used as workspace.
|
||||
c if the computation mode iopt(1)=1 is used the values of
|
||||
c wrk(1),..,wrk(12) should be left unchanged between subsequent
|
||||
c calls.
|
||||
c lwrk : integer. on entry lwrk must specify the actual dimension of
|
||||
c the array wrk as declared in the calling (sub)program.
|
||||
c lwrk must not be too small.
|
||||
c lwrk >= 12+nuest*(mv+nvest+3)+nvest*24+4*mu+8*mv+q
|
||||
c where q is the larger of (mv+nvest) and nuest.
|
||||
c iwrk : integer array of dimension (kwrk). used as workspace.
|
||||
c if the computation mode iopt(1)=1 is used the values of
|
||||
c iwrk(1),.,iwrk(5) should be left unchanged between subsequent
|
||||
c calls.
|
||||
c kwrk : integer. on entry kwrk must specify the actual dimension of
|
||||
c the array iwrk as declared in the calling (sub)program.
|
||||
c kwrk >= 5+mu+mv+nuest+nvest.
|
||||
c ier : integer. unless the routine detects an error, ier contains a
|
||||
c non-positive value on exit, i.e.
|
||||
c ier=0 : normal return. the spline returned has a residual sum of
|
||||
c squares fp such that abs(fp-s)/s <= tol with tol a relat-
|
||||
c ive tolerance set to 0.001 by the program.
|
||||
c ier=-1 : normal return. the spline returned is an interpolating
|
||||
c spline (fp=0).
|
||||
c ier=-2 : normal return. the spline returned is the least-squares
|
||||
c constrained polynomial. in this extreme case fp gives the
|
||||
c upper bound for the smoothing factor s.
|
||||
c ier=1 : error. the required storage space exceeds the available
|
||||
c storage space, as specified by the parameters nuest and
|
||||
c nvest.
|
||||
c probably causes : nuest or nvest too small. if these param-
|
||||
c eters are already large, it may also indicate that s is
|
||||
c too small
|
||||
c the approximation returned is the least-squares spline
|
||||
c according to the current set of knots. the parameter fp
|
||||
c gives the corresponding sum of squared residuals (fp>s).
|
||||
c ier=2 : error. a theoretically impossible result was found during
|
||||
c the iteration process for finding a smoothing spline with
|
||||
c fp = s. probably causes : s too small.
|
||||
c there is an approximation returned but the corresponding
|
||||
c sum of squared residuals does not satisfy the condition
|
||||
c abs(fp-s)/s < tol.
|
||||
c ier=3 : error. the maximal number of iterations maxit (set to 20
|
||||
c by the program) allowed for finding a smoothing spline
|
||||
c with fp=s has been reached. probably causes : s too small
|
||||
c there is an approximation returned but the corresponding
|
||||
c sum of squared residuals does not satisfy the condition
|
||||
c abs(fp-s)/s < tol.
|
||||
c ier=10 : error. on entry, the input data are controlled on validity
|
||||
c the following restrictions must be satisfied.
|
||||
c -1<=iopt(1)<=1, 0<=iopt(2)<=1, 0<=iopt(3)<=1,
|
||||
c -1<=ider(1)<=1, 0<=ider(2)<=1, ider(2)=0 if iopt(2)=0.
|
||||
c -1<=ider(3)<=1, 0<=ider(4)<=1, ider(4)=0 if iopt(3)=0.
|
||||
c mu >= mumin (see above), mv >= 4, nuest >=8, nvest >= 8,
|
||||
c kwrk>=5+mu+mv+nuest+nvest,
|
||||
c lwrk >= 12+nuest*(mv+nvest+3)+nvest*24+4*mu+8*mv+
|
||||
c max(nuest,mv+nvest)
|
||||
c 0< u(i-1)<u(i)< pi,i=2,..,mu,
|
||||
c -pi<=v(1)< pi, v(1)<v(i-1)<v(i)<v(1)+2*pi, i=3,...,mv
|
||||
c if iopt(1)=-1: 8<=nu<=min(nuest,mu+6+iopt(2)+iopt(3))
|
||||
c 0<tu(5)<tu(6)<...<tu(nu-4)< pi
|
||||
c 8<=nv<=min(nvest,mv+7)
|
||||
c v(1)<tv(5)<tv(6)<...<tv(nv-4)<v(1)+2*pi
|
||||
c the schoenberg-whitney conditions, i.e. there must
|
||||
c be subset of grid co-ordinates uu(p) and vv(q) such
|
||||
c that tu(p) < uu(p) < tu(p+4) ,p=1,...,nu-4
|
||||
c (iopt(2)=1 and iopt(3)=1 also count for a uu-value
|
||||
c tv(q) < vv(q) < tv(q+4) ,q=1,...,nv-4
|
||||
c (vv(q) is either a value v(j) or v(j)+2*pi)
|
||||
c if iopt(1)>=0: s>=0
|
||||
c if s=0: nuest>=mu+6+iopt(2)+iopt(3), nvest>=mv+7
|
||||
c if one of these conditions is found to be violated,control
|
||||
c is immediately repassed to the calling program. in that
|
||||
c case there is no approximation returned.
|
||||
c
|
||||
c further comments:
|
||||
c spgrid does not allow individual weighting of the data-values.
|
||||
c so, if these were determined to widely different accuracies, then
|
||||
c perhaps the general data set routine sphere should rather be used
|
||||
c in spite of efficiency.
|
||||
c by means of the parameter s, the user can control the tradeoff
|
||||
c between closeness of fit and smoothness of fit of the approximation.
|
||||
c if s is too large, the spline will be too smooth and signal will be
|
||||
c lost ; if s is too small the spline will pick up too much noise. in
|
||||
c the extreme cases the program will return an interpolating spline if
|
||||
c s=0 and the constrained least-squares polynomial(degrees 3,0)if s is
|
||||
c very large. between these extremes, a properly chosen s will result
|
||||
c in a good compromise between closeness of fit and smoothness of fit.
|
||||
c to decide whether an approximation, corresponding to a certain s is
|
||||
c satisfactory the user is highly recommended to inspect the fits
|
||||
c graphically.
|
||||
c recommended values for s depend on the accuracy of the data values.
|
||||
c if the user has an idea of the statistical errors on the data, he
|
||||
c can also find a proper estimate for s. for, by assuming that, if he
|
||||
c specifies the right s, spgrid will return a spline s(u,v) which
|
||||
c exactly reproduces the function underlying the data he can evaluate
|
||||
c the sum((r(i,j)-s(u(i),v(j)))**2) to find a good estimate for this s
|
||||
c for example, if he knows that the statistical errors on his r(i,j)-
|
||||
c values is not greater than 0.1, he may expect that a good s should
|
||||
c have a value not larger than mu*mv*(0.1)**2.
|
||||
c if nothing is known about the statistical error in r(i,j), s must
|
||||
c be determined by trial and error, taking account of the comments
|
||||
c above. the best is then to start with a very large value of s (to
|
||||
c determine the least-squares polynomial and the corresponding upper
|
||||
c bound fp0 for s) and then to progressively decrease the value of s
|
||||
c ( say by a factor 10 in the beginning, i.e. s=fp0/10,fp0/100,...
|
||||
c and more carefully as the approximation shows more detail) to
|
||||
c obtain closer fits.
|
||||
c to economize the search for a good s-value the program provides with
|
||||
c different modes of computation. at the first call of the routine, or
|
||||
c whenever he wants to restart with the initial set of knots the user
|
||||
c must set iopt(1)=0.
|
||||
c if iopt(1) = 1 the program will continue with the knots found at
|
||||
c the last call of the routine. this will save a lot of computation
|
||||
c time if spgrid is called repeatedly for different values of s.
|
||||
c the number of knots of the spline returned and their location will
|
||||
c depend on the value of s and on the complexity of the shape of the
|
||||
c function underlying the data. if the computation mode iopt(1) = 1
|
||||
c is used, the knots returned may also depend on the s-values at
|
||||
c previous calls (if these were smaller). therefore, if after a number
|
||||
c of trials with different s-values and iopt(1)=1,the user can finally
|
||||
c accept a fit as satisfactory, it may be worthwhile for him to call
|
||||
c spgrid once more with the chosen value for s but now with iopt(1)=0.
|
||||
c indeed, spgrid may then return an approximation of the same quality
|
||||
c of fit but with fewer knots and therefore better if data reduction
|
||||
c is also an important objective for the user.
|
||||
c the number of knots may also depend on the upper bounds nuest and
|
||||
c nvest. indeed, if at a certain stage in spgrid the number of knots
|
||||
c in one direction (say nu) has reached the value of its upper bound
|
||||
c (nuest), then from that moment on all subsequent knots are added
|
||||
c in the other (v) direction. this may indicate that the value of
|
||||
c nuest is too small. on the other hand, it gives the user the option
|
||||
c of limiting the number of knots the routine locates in any direction
|
||||
c for example, by setting nuest=8 (the lowest allowable value for
|
||||
c nuest), the user can indicate that he wants an approximation which
|
||||
c is a simple cubic polynomial in the variable u.
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpspgr,fpchec,fpchep,fpknot,fpopsp,fprati,fpgrsp,fpsysy,fpback,
|
||||
c fpbacp,fpbspl,fpcyt1,fpcyt2,fpdisc,fpgivs,fprota
|
||||
c
|
||||
c references:
|
||||
c dierckx p. : fast algorithms for smoothing data over a disc or a
|
||||
c sphere using tensor product splines, in "algorithms
|
||||
c for approximation", ed. j.c.mason and m.g.cox,
|
||||
c clarendon press oxford, 1987, pp. 51-65
|
||||
c dierckx p. : fast algorithms for smoothing data over a disc or a
|
||||
c sphere using tensor product splines, report tw73, dept.
|
||||
c computer science,k.u.leuven, 1985.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u. leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : july 1985
|
||||
c latest update : march 1989
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 r0,r1,s,fp
|
||||
integer mu,mv,nuest,nvest,nu,nv,lwrk,kwrk,ier
|
||||
c ..array arguments..
|
||||
integer iopt(3),ider(4),iwrk(kwrk)
|
||||
real*8 u(mu),v(mv),r(mu*mv),c((nuest-4)*(nvest-4)),tu(nuest),
|
||||
* tv(nvest),wrk(lwrk)
|
||||
c ..local scalars..
|
||||
real*8 per,pi,tol,uu,ve,rmax,rmin,one,half,rn,rb,re
|
||||
integer i,i1,i2,j,jwrk,j1,j2,kndu,kndv,knru,knrv,kwest,l,
|
||||
* ldr,lfpu,lfpv,lwest,lww,m,maxit,mumin,muu,nc
|
||||
c ..function references..
|
||||
real*8 datan2
|
||||
integer max0
|
||||
c ..subroutine references..
|
||||
c fpchec,fpchep,fpspgr
|
||||
c ..
|
||||
c set constants
|
||||
one = 1d0
|
||||
half = 0.5e0
|
||||
pi = datan2(0d0,-one)
|
||||
per = pi+pi
|
||||
ve = v(1)+per
|
||||
c we set up the parameters tol and maxit.
|
||||
maxit = 20
|
||||
tol = 0.1e-02
|
||||
c before starting computations, a data check is made. if the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(iopt(1).lt.(-1) .or. iopt(1).gt.1) go to 200
|
||||
if(iopt(2).lt.0 .or. iopt(2).gt.1) go to 200
|
||||
if(iopt(3).lt.0 .or. iopt(3).gt.1) go to 200
|
||||
if(ider(1).lt.(-1) .or. ider(1).gt.1) go to 200
|
||||
if(ider(2).lt.0 .or. ider(2).gt.1) go to 200
|
||||
if(ider(2).eq.1 .and. iopt(2).eq.0) go to 200
|
||||
if(ider(3).lt.(-1) .or. ider(3).gt.1) go to 200
|
||||
if(ider(4).lt.0 .or. ider(4).gt.1) go to 200
|
||||
if(ider(4).eq.1 .and. iopt(3).eq.0) go to 200
|
||||
mumin = 4
|
||||
if(ider(1).ge.0) mumin = mumin-1
|
||||
if(iopt(2).eq.1 .and. ider(2).eq.1) mumin = mumin-1
|
||||
if(ider(3).ge.0) mumin = mumin-1
|
||||
if(iopt(3).eq.1 .and. ider(4).eq.1) mumin = mumin-1
|
||||
if(mumin.eq.0) mumin = 1
|
||||
if(mu.lt.mumin .or. mv.lt.4) go to 200
|
||||
if(nuest.lt.8 .or. nvest.lt.8) go to 200
|
||||
m = mu*mv
|
||||
nc = (nuest-4)*(nvest-4)
|
||||
lwest = 12+nuest*(mv+nvest+3)+24*nvest+4*mu+8*mv+
|
||||
* max0(nuest,mv+nvest)
|
||||
kwest = 5+mu+mv+nuest+nvest
|
||||
if(lwrk.lt.lwest .or. kwrk.lt.kwest) go to 200
|
||||
if(u(1).le.0. .or. u(mu).ge.pi) go to 200
|
||||
if(mu.eq.1) go to 30
|
||||
do 20 i=2,mu
|
||||
if(u(i-1).ge.u(i)) go to 200
|
||||
20 continue
|
||||
30 if(v(1).lt. (-pi) .or. v(1).ge.pi ) go to 200
|
||||
if(v(mv).ge.v(1)+per) go to 200
|
||||
do 40 i=2,mv
|
||||
if(v(i-1).ge.v(i)) go to 200
|
||||
40 continue
|
||||
if(iopt(1).gt.0) go to 140
|
||||
c if not given, we compute an estimate for r0.
|
||||
rn = mv
|
||||
if(ider(1).lt.0) go to 45
|
||||
rb = r0
|
||||
go to 55
|
||||
45 rb = 0.
|
||||
do 50 i=1,mv
|
||||
rb = rb+r(i)
|
||||
50 continue
|
||||
rb = rb/rn
|
||||
c if not given, we compute an estimate for r1.
|
||||
55 if(ider(3).lt.0) go to 60
|
||||
re = r1
|
||||
go to 70
|
||||
60 re = 0.
|
||||
j = m
|
||||
do 65 i=1,mv
|
||||
re = re+r(j)
|
||||
j = j-1
|
||||
65 continue
|
||||
re = re/rn
|
||||
c we determine the range of r-values.
|
||||
70 rmin = rb
|
||||
rmax = re
|
||||
do 80 i=1,m
|
||||
if(r(i).lt.rmin) rmin = r(i)
|
||||
if(r(i).gt.rmax) rmax = r(i)
|
||||
80 continue
|
||||
wrk(5) = rb
|
||||
wrk(6) = 0.
|
||||
wrk(7) = 0.
|
||||
wrk(8) = re
|
||||
wrk(9) = 0.
|
||||
wrk(10) = 0.
|
||||
wrk(11) = rmax -rmin
|
||||
wrk(12) = wrk(11)
|
||||
iwrk(4) = mu
|
||||
iwrk(5) = mu
|
||||
if(iopt(1).eq.0) go to 140
|
||||
if(nu.lt.8 .or. nu.gt.nuest) go to 200
|
||||
if(nv.lt.11 .or. nv.gt.nvest) go to 200
|
||||
j = nu
|
||||
do 90 i=1,4
|
||||
tu(i) = 0.
|
||||
tu(j) = pi
|
||||
j = j-1
|
||||
90 continue
|
||||
l = 13
|
||||
wrk(l) = 0.
|
||||
if(iopt(2).eq.0) go to 100
|
||||
l = l+1
|
||||
uu = u(1)
|
||||
if(uu.gt.tu(5)) uu = tu(5)
|
||||
wrk(l) = uu*half
|
||||
100 do 110 i=1,mu
|
||||
l = l+1
|
||||
wrk(l) = u(i)
|
||||
110 continue
|
||||
if(iopt(3).eq.0) go to 120
|
||||
l = l+1
|
||||
uu = u(mu)
|
||||
if(uu.lt.tu(nu-4)) uu = tu(nu-4)
|
||||
wrk(l) = uu+(pi-uu)*half
|
||||
120 l = l+1
|
||||
wrk(l) = pi
|
||||
muu = l-12
|
||||
call fpchec(wrk(13),muu,tu,nu,3,ier)
|
||||
if(ier.ne.0) go to 200
|
||||
j1 = 4
|
||||
tv(j1) = v(1)
|
||||
i1 = nv-3
|
||||
tv(i1) = ve
|
||||
j2 = j1
|
||||
i2 = i1
|
||||
do 130 i=1,3
|
||||
i1 = i1+1
|
||||
i2 = i2-1
|
||||
j1 = j1+1
|
||||
j2 = j2-1
|
||||
tv(j2) = tv(i2)-per
|
||||
tv(i1) = tv(j1)+per
|
||||
130 continue
|
||||
l = 13
|
||||
do 135 i=1,mv
|
||||
wrk(l) = v(i)
|
||||
l = l+1
|
||||
135 continue
|
||||
wrk(l) = ve
|
||||
call fpchep(wrk(13),mv+1,tv,nv,3,ier)
|
||||
if (ier.eq.0) go to 150
|
||||
go to 200
|
||||
140 if(s.lt.0.) go to 200
|
||||
if(s.eq.0. .and. (nuest.lt.(mu+6+iopt(2)+iopt(3)) .or.
|
||||
* nvest.lt.(mv+7)) ) go to 200
|
||||
c we partition the working space and determine the spline approximation
|
||||
150 ldr = 5
|
||||
lfpu = 13
|
||||
lfpv = lfpu+nuest
|
||||
lww = lfpv+nvest
|
||||
jwrk = lwrk-12-nuest-nvest
|
||||
knru = 6
|
||||
knrv = knru+mu
|
||||
kndu = knrv+mv
|
||||
kndv = kndu+nuest
|
||||
call fpspgr(iopt,ider,u,mu,v,mv,r,m,rb,re,s,nuest,nvest,tol,maxit,
|
||||
*
|
||||
* nc,nu,tu,nv,tv,c,fp,wrk(1),wrk(2),wrk(3),wrk(4),wrk(lfpu),
|
||||
* wrk(lfpv),wrk(ldr),wrk(11),iwrk(1),iwrk(2),iwrk(3),iwrk(4),
|
||||
* iwrk(5),iwrk(knru),iwrk(knrv),iwrk(kndu),iwrk(kndv),wrk(lww),
|
||||
* jwrk,ier)
|
||||
200 return
|
||||
end
|
||||
405
cxx/fitpack/sphere.f
Normal file
405
cxx/fitpack/sphere.f
Normal file
@ -0,0 +1,405 @@
|
||||
recursive subroutine sphere(iopt,m,teta,phi,r,w,s,ntest,npest,
|
||||
* eps,nt,tt,np,tp,c,fp,wrk1,lwrk1,wrk2,lwrk2,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c subroutine sphere determines a smooth bicubic spherical spline
|
||||
c approximation s(teta,phi), 0 <= teta <= pi ; 0 <= phi <= 2*pi
|
||||
c to a given set of data points (teta(i),phi(i),r(i)),i=1,2,...,m.
|
||||
c such a spline has the following specific properties
|
||||
c
|
||||
c (1) s(0,phi) = constant 0 <=phi<= 2*pi.
|
||||
c
|
||||
c (2) s(pi,phi) = constant 0 <=phi<= 2*pi
|
||||
c
|
||||
c j j
|
||||
c d s(teta,0) d s(teta,2*pi)
|
||||
c (3) ----------- = ------------ 0 <=teta<=pi, j=0,1,2
|
||||
c j j
|
||||
c d phi d phi
|
||||
c
|
||||
c d s(0,phi) d s(0,0) d s(0,pi/2)
|
||||
c (4) ---------- = -------- *cos(phi) + ----------- *sin(phi)
|
||||
c d teta d teta d teta
|
||||
c
|
||||
c d s(pi,phi) d s(pi,0) d s(pi,pi/2)
|
||||
c (5) ----------- = ---------*cos(phi) + ------------*sin(phi)
|
||||
c d teta d teta d teta
|
||||
c
|
||||
c if iopt =-1 sphere calculates a weighted least-squares spherical
|
||||
c spline according to a given set of knots in teta- and phi- direction.
|
||||
c if iopt >=0, the number of knots in each direction and their position
|
||||
c tt(j),j=1,2,...,nt ; tp(j),j=1,2,...,np are chosen automatically by
|
||||
c the routine. the smoothness of s(teta,phi) is then achieved by mini-
|
||||
c malizing the discontinuity jumps of the derivatives of the spline
|
||||
c at the knots. the amount of smoothness of s(teta,phi) is determined
|
||||
c by the condition that fp = sum((w(i)*(r(i)-s(teta(i),phi(i))))**2)
|
||||
c be <= s, with s a given non-negative constant.
|
||||
c the spherical spline is given in the standard b-spline representation
|
||||
c of bicubic splines and can be evaluated by means of subroutine bispev
|
||||
c
|
||||
c calling sequence:
|
||||
c call sphere(iopt,m,teta,phi,r,w,s,ntest,npest,eps,
|
||||
c * nt,tt,np,tp,c,fp,wrk1,lwrk1,wrk2,lwrk2,iwrk,kwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt : integer flag. on entry iopt must specify whether a weighted
|
||||
c least-squares spherical spline (iopt=-1) or a smoothing
|
||||
c spherical spline (iopt=0 or 1) must be determined.
|
||||
c if iopt=0 the routine will start with an initial set of knots
|
||||
c tt(i)=0,tt(i+4)=pi,i=1,...,4;tp(i)=0,tp(i+4)=2*pi,i=1,...,4.
|
||||
c if iopt=1 the routine will continue with the set of knots
|
||||
c found at the last call of the routine.
|
||||
c attention: a call with iopt=1 must always be immediately pre-
|
||||
c ceded by another call with iopt=1 or iopt=0.
|
||||
c unchanged on exit.
|
||||
c m : integer. on entry m must specify the number of data points.
|
||||
c m >= 2. unchanged on exit.
|
||||
c teta : real array of dimension at least (m).
|
||||
c phi : real array of dimension at least (m).
|
||||
c r : real array of dimension at least (m).
|
||||
c before entry,teta(i),phi(i),r(i) must be set to the spherical
|
||||
c co-ordinates of the i-th data point, for i=1,...,m.the order
|
||||
c of the data points is immaterial. unchanged on exit.
|
||||
c w : real array of dimension at least (m). before entry, w(i) must
|
||||
c be set to the i-th value in the set of weights. the w(i) must
|
||||
c be strictly positive. unchanged on exit.
|
||||
c s : real. on entry (in case iopt>=0) s must specify the smoothing
|
||||
c factor. s >=0. unchanged on exit.
|
||||
c for advice on the choice of s see further comments
|
||||
c ntest : integer. unchanged on exit.
|
||||
c npest : integer. unchanged on exit.
|
||||
c on entry, ntest and npest must specify an upper bound for the
|
||||
c number of knots required in the teta- and phi-directions.
|
||||
c these numbers will also determine the storage space needed by
|
||||
c the routine. ntest >= 8, npest >= 8.
|
||||
c in most practical situation ntest = npest = 8+sqrt(m/2) will
|
||||
c be sufficient. see also further comments.
|
||||
c eps : real.
|
||||
c on entry, eps must specify a threshold for determining the
|
||||
c effective rank of an over-determined linear system of equat-
|
||||
c ions. 0 < eps < 1. if the number of decimal digits in the
|
||||
c computer representation of a real number is q, then 10**(-q)
|
||||
c is a suitable value for eps in most practical applications.
|
||||
c unchanged on exit.
|
||||
c nt : integer.
|
||||
c unless ier=10 (in case iopt >=0), nt will contain the total
|
||||
c number of knots with respect to the teta-variable, of the
|
||||
c spline approximation returned. if the computation mode iopt=1
|
||||
c is used, the value of nt should be left unchanged between
|
||||
c subsequent calls.
|
||||
c in case iopt=-1, the value of nt should be specified on entry
|
||||
c tt : real array of dimension at least ntest.
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline with respect to the teta-variable, i.e. the position
|
||||
c of the interior knots tt(5),...,tt(nt-4) as well as the
|
||||
c position of the additional knots tt(1)=...=tt(4)=0 and
|
||||
c tt(nt-3)=...=tt(nt)=pi needed for the b-spline representation
|
||||
c if the computation mode iopt=1 is used, the values of tt(1),
|
||||
c ...,tt(nt) should be left unchanged between subsequent calls.
|
||||
c if the computation mode iopt=-1 is used, the values tt(5),
|
||||
c ...tt(nt-4) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c np : integer.
|
||||
c unless ier=10 (in case iopt >=0), np will contain the total
|
||||
c number of knots with respect to the phi-variable, of the
|
||||
c spline approximation returned. if the computation mode iopt=1
|
||||
c is used, the value of np should be left unchanged between
|
||||
c subsequent calls.
|
||||
c in case iopt=-1, the value of np (>=9) should be specified
|
||||
c on entry.
|
||||
c tp : real array of dimension at least npest.
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline with respect to the phi-variable, i.e. the position of
|
||||
c the interior knots tp(5),...,tp(np-4) as well as the position
|
||||
c of the additional knots tp(1),...,tp(4) and tp(np-3),...,
|
||||
c tp(np) needed for the b-spline representation.
|
||||
c if the computation mode iopt=1 is used, the values of tp(1),
|
||||
c ...,tp(np) should be left unchanged between subsequent calls.
|
||||
c if the computation mode iopt=-1 is used, the values tp(5),
|
||||
c ...tp(np-4) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c c : real array of dimension at least (ntest-4)*(npest-4).
|
||||
c on successful exit, c contains the coefficients of the spline
|
||||
c approximation s(teta,phi).
|
||||
c fp : real. unless ier=10, fp contains the weighted sum of
|
||||
c squared residuals of the spline approximation returned.
|
||||
c wrk1 : real array of dimension (lwrk1). used as workspace.
|
||||
c if the computation mode iopt=1 is used the value of wrk1(1)
|
||||
c should be left unchanged between subsequent calls.
|
||||
c on exit wrk1(2),wrk1(3),...,wrk1(1+ncof) will contain the
|
||||
c values d(i)/max(d(i)),i=1,...,ncof=6+(np-7)*(nt-8)
|
||||
c with d(i) the i-th diagonal element of the reduced triangular
|
||||
c matrix for calculating the b-spline coefficients. it includes
|
||||
c those elements whose square is less than eps,which are treat-
|
||||
c ed as 0 in the case of presumed rank deficiency (ier<-2).
|
||||
c lwrk1 : integer. on entry lwrk1 must specify the actual dimension of
|
||||
c the array wrk1 as declared in the calling (sub)program.
|
||||
c lwrk1 must not be too small. let
|
||||
c u = ntest-7, v = npest-7, then
|
||||
c lwrk1 >= 185+52*v+10*u+14*u*v+8*(u-1)*v**2+8*m
|
||||
c wrk2 : real array of dimension (lwrk2). used as workspace, but
|
||||
c only in the case a rank deficient system is encountered.
|
||||
c lwrk2 : integer. on entry lwrk2 must specify the actual dimension of
|
||||
c the array wrk2 as declared in the calling (sub)program.
|
||||
c lwrk2 > 0 . a save upper bound for lwrk2 = 48+21*v+7*u*v+
|
||||
c 4*(u-1)*v**2 where u,v are as above. if there are enough data
|
||||
c points, scattered uniformly over the approximation domain
|
||||
c and if the smoothing factor s is not too small, there is a
|
||||
c good chance that this extra workspace is not needed. a lot
|
||||
c of memory might therefore be saved by setting lwrk2=1.
|
||||
c (see also ier > 10)
|
||||
c iwrk : integer array of dimension (kwrk). used as workspace.
|
||||
c kwrk : integer. on entry kwrk must specify the actual dimension of
|
||||
c the array iwrk as declared in the calling (sub)program.
|
||||
c kwrk >= m+(ntest-7)*(npest-7).
|
||||
c ier : integer. unless the routine detects an error, ier contains a
|
||||
c non-positive value on exit, i.e.
|
||||
c ier=0 : normal return. the spline returned has a residual sum of
|
||||
c squares fp such that abs(fp-s)/s <= tol with tol a relat-
|
||||
c ive tolerance set to 0.001 by the program.
|
||||
c ier=-1 : normal return. the spline returned is a spherical
|
||||
c interpolating spline (fp=0).
|
||||
c ier=-2 : normal return. the spline returned is the weighted least-
|
||||
c squares constrained polynomial . in this extreme case
|
||||
c fp gives the upper bound for the smoothing factor s.
|
||||
c ier<-2 : warning. the coefficients of the spline returned have been
|
||||
c computed as the minimal norm least-squares solution of a
|
||||
c (numerically) rank deficient system. (-ier) gives the rank.
|
||||
c especially if the rank deficiency which can be computed as
|
||||
c 6+(nt-8)*(np-7)+ier, is large the results may be inaccurate
|
||||
c they could also seriously depend on the value of eps.
|
||||
c ier=1 : error. the required storage space exceeds the available
|
||||
c storage space, as specified by the parameters ntest and
|
||||
c npest.
|
||||
c probably causes : ntest or npest too small. if these param-
|
||||
c eters are already large, it may also indicate that s is
|
||||
c too small
|
||||
c the approximation returned is the weighted least-squares
|
||||
c spherical spline according to the current set of knots.
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=2 : error. a theoretically impossible result was found during
|
||||
c the iteration process for finding a smoothing spline with
|
||||
c fp = s. probably causes : s too small or badly chosen eps.
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=3 : error. the maximal number of iterations maxit (set to 20
|
||||
c by the program) allowed for finding a smoothing spline
|
||||
c with fp=s has been reached. probably causes : s too small
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=4 : error. no more knots can be added because the dimension
|
||||
c of the spherical spline 6+(nt-8)*(np-7) already exceeds
|
||||
c the number of data points m.
|
||||
c probably causes : either s or m too small.
|
||||
c the approximation returned is the weighted least-squares
|
||||
c spherical spline according to the current set of knots.
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=5 : error. no more knots can be added because the additional
|
||||
c knot would (quasi) coincide with an old one.
|
||||
c probably causes : s too small or too large a weight to an
|
||||
c inaccurate data point.
|
||||
c the approximation returned is the weighted least-squares
|
||||
c spherical spline according to the current set of knots.
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=10 : error. on entry, the input data are controlled on validity
|
||||
c the following restrictions must be satisfied.
|
||||
c -1<=iopt<=1, m>=2, ntest>=8 ,npest >=8, 0<eps<1,
|
||||
c 0<=teta(i)<=pi, 0<=phi(i)<=2*pi, w(i)>0, i=1,...,m
|
||||
c lwrk1 >= 185+52*v+10*u+14*u*v+8*(u-1)*v**2+8*m
|
||||
c kwrk >= m+(ntest-7)*(npest-7)
|
||||
c if iopt=-1: 8<=nt<=ntest , 9<=np<=npest
|
||||
c 0<tt(5)<tt(6)<...<tt(nt-4)<pi
|
||||
c 0<tp(5)<tp(6)<...<tp(np-4)<2*pi
|
||||
c if iopt>=0: s>=0
|
||||
c if one of these conditions is found to be violated,control
|
||||
c is immediately repassed to the calling program. in that
|
||||
c case there is no approximation returned.
|
||||
c ier>10 : error. lwrk2 is too small, i.e. there is not enough work-
|
||||
c space for computing the minimal least-squares solution of
|
||||
c a rank deficient system of linear equations. ier gives the
|
||||
c requested value for lwrk2. there is no approximation re-
|
||||
c turned but, having saved the information contained in nt,
|
||||
c np,tt,tp,wrk1, and having adjusted the value of lwrk2 and
|
||||
c the dimension of the array wrk2 accordingly, the user can
|
||||
c continue at the point the program was left, by calling
|
||||
c sphere with iopt=1.
|
||||
c
|
||||
c further comments:
|
||||
c by means of the parameter s, the user can control the tradeoff
|
||||
c between closeness of fit and smoothness of fit of the approximation.
|
||||
c if s is too large, the spline will be too smooth and signal will be
|
||||
c lost ; if s is too small the spline will pick up too much noise. in
|
||||
c the extreme cases the program will return an interpolating spline if
|
||||
c s=0 and the constrained weighted least-squares polynomial if s is
|
||||
c very large. between these extremes, a properly chosen s will result
|
||||
c in a good compromise between closeness of fit and smoothness of fit.
|
||||
c to decide whether an approximation, corresponding to a certain s is
|
||||
c satisfactory the user is highly recommended to inspect the fits
|
||||
c graphically.
|
||||
c recommended values for s depend on the weights w(i). if these are
|
||||
c taken as 1/d(i) with d(i) an estimate of the standard deviation of
|
||||
c r(i), a good s-value should be found in the range (m-sqrt(2*m),m+
|
||||
c sqrt(2*m)). if nothing is known about the statistical error in r(i)
|
||||
c each w(i) can be set equal to one and s determined by trial and
|
||||
c error, taking account of the comments above. the best is then to
|
||||
c start with a very large value of s ( to determine the least-squares
|
||||
c polynomial and the corresponding upper bound fp0 for s) and then to
|
||||
c progressively decrease the value of s ( say by a factor 10 in the
|
||||
c beginning, i.e. s=fp0/10, fp0/100,...and more carefully as the
|
||||
c approximation shows more detail) to obtain closer fits.
|
||||
c to choose s very small is strongly discouraged. this considerably
|
||||
c increases computation time and memory requirements. it may also
|
||||
c cause rank-deficiency (ier<-2) and endager numerical stability.
|
||||
c to economize the search for a good s-value the program provides with
|
||||
c different modes of computation. at the first call of the routine, or
|
||||
c whenever he wants to restart with the initial set of knots the user
|
||||
c must set iopt=0.
|
||||
c if iopt=1 the program will continue with the set of knots found at
|
||||
c the last call of the routine. this will save a lot of computation
|
||||
c time if sphere is called repeatedly for different values of s.
|
||||
c the number of knots of the spline returned and their location will
|
||||
c depend on the value of s and on the complexity of the shape of the
|
||||
c function underlying the data. if the computation mode iopt=1
|
||||
c is used, the knots returned may also depend on the s-values at
|
||||
c previous calls (if these were smaller). therefore, if after a number
|
||||
c of trials with different s-values and iopt=1, the user can finally
|
||||
c accept a fit as satisfactory, it may be worthwhile for him to call
|
||||
c sphere once more with the selected value for s but now with iopt=0.
|
||||
c indeed, sphere may then return an approximation of the same quality
|
||||
c of fit but with fewer knots and therefore better if data reduction
|
||||
c is also an important objective for the user.
|
||||
c the number of knots may also depend on the upper bounds ntest and
|
||||
c npest. indeed, if at a certain stage in sphere the number of knots
|
||||
c in one direction (say nt) has reached the value of its upper bound
|
||||
c (ntest), then from that moment on all subsequent knots are added
|
||||
c in the other (phi) direction. this may indicate that the value of
|
||||
c ntest is too small. on the other hand, it gives the user the option
|
||||
c of limiting the number of knots the routine locates in any direction
|
||||
c for example, by setting ntest=8 (the lowest allowable value for
|
||||
c ntest), the user can indicate that he wants an approximation which
|
||||
c is a cubic polynomial in the variable teta.
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpback,fpbspl,fpsphe,fpdisc,fpgivs,fprank,fprati,fprota,fporde,
|
||||
c fprpsp
|
||||
c
|
||||
c references:
|
||||
c dierckx p. : algorithms for smoothing data on the sphere with tensor
|
||||
c product splines, computing 32 (1984) 319-342.
|
||||
c dierckx p. : algorithms for smoothing data on the sphere with tensor
|
||||
c product splines, report tw62, dept. computer science,
|
||||
c k.u.leuven, 1983.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u. leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : july 1983
|
||||
c latest update : march 1989
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 s,eps,fp
|
||||
integer iopt,m,ntest,npest,nt,np,lwrk1,lwrk2,kwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 teta(m),phi(m),r(m),w(m),tt(ntest),tp(npest),
|
||||
* c((ntest-4)*(npest-4)),wrk1(lwrk1),wrk2(lwrk2)
|
||||
integer iwrk(kwrk)
|
||||
c ..local scalars..
|
||||
real*8 tol,pi,pi2,one
|
||||
integer i,ib1,ib3,ki,kn,kwest,la,lbt,lcc,lcs,lro,j,
|
||||
* lbp,lco,lf,lff,lfp,lh,lq,lst,lsp,lwest,maxit,ncest,ncc,ntt,
|
||||
* npp,nreg,nrint,ncof,nt4,np4
|
||||
c ..function references..
|
||||
real*8 atan
|
||||
c ..subroutine references..
|
||||
c fpsphe
|
||||
c ..
|
||||
c set constants
|
||||
one = 0.1e+01
|
||||
c we set up the parameters tol and maxit.
|
||||
maxit = 20
|
||||
tol = 0.1e-02
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid,control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(eps.le.0. .or. eps.ge.1.) go to 80
|
||||
if(iopt.lt.(-1) .or. iopt.gt.1) go to 80
|
||||
if(m.lt.2) go to 80
|
||||
if(ntest.lt.8 .or. npest.lt.8) go to 80
|
||||
nt4 = ntest-4
|
||||
np4 = npest-4
|
||||
ncest = nt4*np4
|
||||
ntt = ntest-7
|
||||
npp = npest-7
|
||||
ncc = 6+npp*(ntt-1)
|
||||
nrint = ntt+npp
|
||||
nreg = ntt*npp
|
||||
ncof = 6+3*npp
|
||||
ib1 = 4*npp
|
||||
ib3 = ib1+3
|
||||
if(ncof.gt.ib1) ib1 = ncof
|
||||
if(ncof.gt.ib3) ib3 = ncof
|
||||
lwest = 185+52*npp+10*ntt+14*ntt*npp+8*(m+(ntt-1)*npp**2)
|
||||
kwest = m+nreg
|
||||
if(lwrk1.lt.lwest .or. kwrk.lt.kwest) go to 80
|
||||
if(iopt.gt.0) go to 60
|
||||
pi = atan(one)*4
|
||||
pi2 = pi+pi
|
||||
do 20 i=1,m
|
||||
if(w(i).le.0.) go to 80
|
||||
if(teta(i).lt.0. .or. teta(i).gt.pi) go to 80
|
||||
if(phi(i) .lt.0. .or. phi(i).gt.pi2) go to 80
|
||||
20 continue
|
||||
if(iopt.eq.0) go to 60
|
||||
ntt = nt-8
|
||||
if(ntt.lt.0 .or. nt.gt.ntest) go to 80
|
||||
if(ntt.eq.0) go to 40
|
||||
tt(4) = 0.
|
||||
do 30 i=1,ntt
|
||||
j = i+4
|
||||
if(tt(j).le.tt(j-1) .or. tt(j).ge.pi) go to 80
|
||||
30 continue
|
||||
40 npp = np-8
|
||||
if(npp.lt.1 .or. np.gt.npest) go to 80
|
||||
tp(4) = 0.
|
||||
do 50 i=1,npp
|
||||
j = i+4
|
||||
if(tp(j).le.tp(j-1) .or. tp(j).ge.pi2) go to 80
|
||||
50 continue
|
||||
go to 70
|
||||
60 if(s.lt.0.) go to 80
|
||||
70 ier = 0
|
||||
c we partition the working space and determine the spline approximation
|
||||
kn = 1
|
||||
ki = kn+m
|
||||
lq = 2
|
||||
la = lq+ncc*ib3
|
||||
lf = la+ncc*ib1
|
||||
lff = lf+ncc
|
||||
lfp = lff+ncest
|
||||
lco = lfp+nrint
|
||||
lh = lco+nrint
|
||||
lbt = lh+ib3
|
||||
lbp = lbt+5*ntest
|
||||
lro = lbp+5*npest
|
||||
lcc = lro+npest
|
||||
lcs = lcc+npest
|
||||
lst = lcs+npest
|
||||
lsp = lst+m*4
|
||||
call fpsphe(iopt,m,teta,phi,r,w,s,ntest,npest,eps,tol,maxit,
|
||||
* ib1,ib3,ncest,ncc,nrint,nreg,nt,tt,np,tp,c,fp,wrk1(1),wrk1(lfp),
|
||||
* wrk1(lco),wrk1(lf),wrk1(lff),wrk1(lro),wrk1(lcc),wrk1(lcs),
|
||||
* wrk1(la),wrk1(lq),wrk1(lbt),wrk1(lbp),wrk1(lst),wrk1(lsp),
|
||||
* wrk1(lh),iwrk(ki),iwrk(kn),wrk2,lwrk2,ier)
|
||||
80 return
|
||||
end
|
||||
|
||||
193
cxx/fitpack/splder.f
Normal file
193
cxx/fitpack/splder.f
Normal file
@ -0,0 +1,193 @@
|
||||
recursive subroutine splder(t,n,c,nc,k,nu,x,y,m,e,wrk,ier)
|
||||
implicit none
|
||||
c subroutine splder evaluates in a number of points x(i),i=1,2,...,m
|
||||
c the derivative of order nu of a spline s(x) of degree k,given in
|
||||
c its b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c call splder(t,n,c,nc,k,nu,x,y,m,e,wrk,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c t : array,length n, which contains the position of the knots.
|
||||
c n : integer, giving the total number of knots of s(x).
|
||||
c c : array,length nc, containing the b-spline coefficients.
|
||||
c the length of the array, nc >= n - k -1.
|
||||
c further coefficients are ignored.
|
||||
c k : integer, giving the degree of s(x).
|
||||
c nu : integer, specifying the order of the derivative. 0<=nu<=k
|
||||
c x : array,length m, which contains the points where the deriv-
|
||||
c ative of s(x) must be evaluated.
|
||||
c m : integer, giving the number of points where the derivative
|
||||
c of s(x) must be evaluated
|
||||
c e : integer, if 0 the spline is extrapolated from the end
|
||||
c spans for points not in the support, if 1 the spline
|
||||
c evaluates to zero for those points, and if 2 ier is set to
|
||||
c 1 and the subroutine returns.
|
||||
c wrk : real array of dimension n. used as working space.
|
||||
c
|
||||
c output parameters:
|
||||
c y : array,length m, giving the value of the derivative of s(x)
|
||||
c at the different points.
|
||||
c ier : error flag
|
||||
c ier = 0 : normal return
|
||||
c ier = 1 : argument out of bounds and e == 2
|
||||
c ier =10 : invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c 0 <= nu <= k
|
||||
c m >= 1
|
||||
c t(k+1) <= x(i) <= x(i+1) <= t(n-k) , i=1,2,...,m-1.
|
||||
c
|
||||
c other subroutines required: fpbspl
|
||||
c
|
||||
c references :
|
||||
c de boor c : on calculating with b-splines, j. approximation theory
|
||||
c 6 (1972) 50-62.
|
||||
c cox m.g. : the numerical evaluation of b-splines, j. inst. maths
|
||||
c applics 10 (1972) 134-149.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1987
|
||||
c
|
||||
c++ pearu: 13 aug 20003
|
||||
c++ - disabled cliping x values to interval [min(t),max(t)]
|
||||
c++ - removed the restriction of the orderness of x values
|
||||
c++ - fixed initialization of sp to double precision value
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer n,nc,k,nu,m,e,ier
|
||||
c ..array arguments..
|
||||
real*8 t(n),c(nc),x(m),y(m),wrk(n)
|
||||
c ..local scalars..
|
||||
integer i,j,kk,k1,k2,l,ll,l1,l2,nk1,nk2,nn
|
||||
real*8 ak,arg,fac,sp,tb,te
|
||||
c++..
|
||||
integer k3
|
||||
c..++
|
||||
c ..local arrays ..
|
||||
real*8 h(6)
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(nu.lt.0 .or. nu.gt.k) go to 200
|
||||
c-- if(m-1) 200,30,10
|
||||
c++..
|
||||
if(m.lt.1) go to 200
|
||||
c..++
|
||||
c-- 10 do 20 i=2,m
|
||||
c-- if(x(i).lt.x(i-1)) go to 200
|
||||
c-- 20 continue
|
||||
ier = 0
|
||||
c fetch tb and te, the boundaries of the approximation interval.
|
||||
k1 = k+1
|
||||
k3 = k1+1
|
||||
nk1 = n-k1
|
||||
tb = t(k1)
|
||||
te = t(nk1+1)
|
||||
c the derivative of order nu of a spline of degree k is a spline of
|
||||
c degree k-nu,the b-spline coefficients wrk(i) of which can be found
|
||||
c using the recurrence scheme of de boor.
|
||||
l = 1
|
||||
kk = k
|
||||
nn = n
|
||||
do 40 i=1,nk1
|
||||
wrk(i) = c(i)
|
||||
40 continue
|
||||
if(nu.eq.0) go to 100
|
||||
nk2 = nk1
|
||||
do 60 j=1,nu
|
||||
ak = kk
|
||||
nk2 = nk2-1
|
||||
l1 = l
|
||||
do 50 i=1,nk2
|
||||
l1 = l1+1
|
||||
l2 = l1+kk
|
||||
fac = t(l2)-t(l1)
|
||||
if(fac.le.0.) go to 50
|
||||
wrk(i) = ak*(wrk(i+1)-wrk(i))/fac
|
||||
50 continue
|
||||
l = l+1
|
||||
kk = kk-1
|
||||
60 continue
|
||||
if(kk.ne.0) go to 100
|
||||
c if nu=k the derivative is a piecewise constant function
|
||||
j = 1
|
||||
do 90 i=1,m
|
||||
arg = x(i)
|
||||
c++..
|
||||
c check if arg is in the support
|
||||
if (arg .lt. tb .or. arg .gt. te) then
|
||||
if (e .eq. 0) then
|
||||
goto 65
|
||||
else if (e .eq. 1) then
|
||||
y(i) = 0
|
||||
goto 90
|
||||
else if (e .eq. 2) then
|
||||
ier = 1
|
||||
goto 200
|
||||
endif
|
||||
endif
|
||||
c search for knot interval t(l) <= arg < t(l+1)
|
||||
65 if(arg.ge.t(l) .or. l+1.eq.k3) go to 70
|
||||
l1 = l
|
||||
l = l-1
|
||||
j = j-1
|
||||
go to 65
|
||||
c..++
|
||||
70 if(arg.lt.t(l+1) .or. l.eq.nk1) go to 80
|
||||
l = l+1
|
||||
j = j+1
|
||||
go to 70
|
||||
80 y(i) = wrk(j)
|
||||
90 continue
|
||||
go to 200
|
||||
|
||||
100 l = k1
|
||||
l1 = l+1
|
||||
k2 = k1-nu
|
||||
c main loop for the different points.
|
||||
do 180 i=1,m
|
||||
c fetch a new x-value arg.
|
||||
arg = x(i)
|
||||
c check if arg is in the support
|
||||
if (arg .lt. tb .or. arg .gt. te) then
|
||||
if (e .eq. 0) then
|
||||
goto 135
|
||||
else if (e .eq. 1) then
|
||||
y(i) = 0
|
||||
goto 180
|
||||
else if (e .eq. 2) then
|
||||
ier = 1
|
||||
goto 200
|
||||
endif
|
||||
endif
|
||||
c search for knot interval t(l) <= arg < t(l+1)
|
||||
135 if(arg.ge.t(l) .or. l1.eq.k3) go to 140
|
||||
l1 = l
|
||||
l = l-1
|
||||
go to 135
|
||||
c..++
|
||||
140 if(arg.lt.t(l1) .or. l.eq.nk1) go to 150
|
||||
l = l1
|
||||
l1 = l+1
|
||||
go to 140
|
||||
c evaluate the non-zero b-splines of degree k-nu at arg.
|
||||
150 call fpbspl(t,n,kk,arg,l,h)
|
||||
c find the value of the derivative at x=arg.
|
||||
sp = 0.0d0
|
||||
ll = l-k1
|
||||
do 160 j=1,k2
|
||||
ll = ll+1
|
||||
sp = sp+wrk(ll)*h(j)
|
||||
160 continue
|
||||
y(i) = sp
|
||||
180 continue
|
||||
200 return
|
||||
end
|
||||
139
cxx/fitpack/splev.f
Normal file
139
cxx/fitpack/splev.f
Normal file
@ -0,0 +1,139 @@
|
||||
recursive subroutine splev(t,n,c,nc,k,x,y,m,e,ier)
|
||||
c subroutine splev evaluates in a number of points x(i),i=1,2,...,m
|
||||
c a spline s(x) of degree k, given in its b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c call splev(t,n,c,nc,k,x,y,m,e,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c t : array,length n, which contains the position of the knots.
|
||||
c n : integer, giving the total number of knots of s(x).
|
||||
c c : array,length nc, containing the b-spline coefficients.
|
||||
c the length of the array, nc >= n - k -1.
|
||||
c further coefficients are ignored.
|
||||
c k : integer, giving the degree of s(x).
|
||||
c x : array,length m, which contains the points where s(x) must
|
||||
c be evaluated.
|
||||
c m : integer, giving the number of points where s(x) must be
|
||||
c evaluated.
|
||||
c e : integer, if 0 the spline is extrapolated from the end
|
||||
c spans for points not in the support, if 1 the spline
|
||||
c evaluates to zero for those points, if 2 ier is set to
|
||||
c 1 and the subroutine returns, and if 3 the spline evaluates
|
||||
c to the value of the nearest boundary point.
|
||||
c
|
||||
c output parameter:
|
||||
c y : array,length m, giving the value of s(x) at the different
|
||||
c points.
|
||||
c ier : error flag
|
||||
c ier = 0 : normal return
|
||||
c ier = 1 : argument out of bounds and e == 2
|
||||
c ier =10 : invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c m >= 1
|
||||
c-- t(k+1) <= x(i) <= x(i+1) <= t(n-k) , i=1,2,...,m-1.
|
||||
c
|
||||
c other subroutines required: fpbspl.
|
||||
c
|
||||
c references :
|
||||
c de boor c : on calculating with b-splines, j. approximation theory
|
||||
c 6 (1972) 50-62.
|
||||
c cox m.g. : the numerical evaluation of b-splines, j. inst. maths
|
||||
c applics 10 (1972) 134-149.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1987
|
||||
c
|
||||
c++ pearu: 11 aug 2003
|
||||
c++ - disabled cliping x values to interval [min(t),max(t)]
|
||||
c++ - removed the restriction of the orderness of x values
|
||||
c++ - fixed initialization of sp to double precision value
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer n, k, m, e, ier
|
||||
c ..array arguments..
|
||||
real*8 t(n), c(nc), x(m), y(m)
|
||||
c ..local scalars..
|
||||
integer i, j, k1, l, ll, l1, nk1
|
||||
c++..
|
||||
integer k2
|
||||
c..++
|
||||
real*8 arg, sp, tb, te
|
||||
c ..local array..
|
||||
real*8 h(20)
|
||||
c ..
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
c-- if(m-1) 100,30,10
|
||||
c++..
|
||||
if (m .lt. 1) go to 100
|
||||
c..++
|
||||
c-- 10 do 20 i=2,m
|
||||
c-- if(x(i).lt.x(i-1)) go to 100
|
||||
c-- 20 continue
|
||||
ier = 0
|
||||
c fetch tb and te, the boundaries of the approximation interval.
|
||||
k1 = k + 1
|
||||
c++..
|
||||
k2 = k1 + 1
|
||||
c..++
|
||||
nk1 = n - k1
|
||||
tb = t(k1)
|
||||
te = t(nk1 + 1)
|
||||
l = k1
|
||||
l1 = l + 1
|
||||
c main loop for the different points.
|
||||
do 80 i = 1, m
|
||||
c fetch a new x-value arg.
|
||||
arg = x(i)
|
||||
c check if arg is in the support
|
||||
if (arg .lt. tb .or. arg .gt. te) then
|
||||
if (e .eq. 0) then
|
||||
goto 35
|
||||
else if (e .eq. 1) then
|
||||
y(i) = 0
|
||||
goto 80
|
||||
else if (e .eq. 2) then
|
||||
ier = 1
|
||||
goto 100
|
||||
else if (e .eq. 3) then
|
||||
if (arg .lt. tb) then
|
||||
arg = tb
|
||||
else
|
||||
arg = te
|
||||
endif
|
||||
endif
|
||||
endif
|
||||
c search for knot interval t(l) <= arg < t(l+1)
|
||||
c++..
|
||||
35 if (arg .ge. t(l) .or. l1 .eq. k2) go to 40
|
||||
l1 = l
|
||||
l = l - 1
|
||||
go to 35
|
||||
c..++
|
||||
40 if(arg .lt. t(l1) .or. l .eq. nk1) go to 50
|
||||
l = l1
|
||||
l1 = l + 1
|
||||
go to 40
|
||||
c evaluate the non-zero b-splines at arg.
|
||||
50 call fpbspl(t, n, k, arg, l, h)
|
||||
c find the value of s(x) at x=arg.
|
||||
sp = 0.0d0
|
||||
ll = l - k1
|
||||
do 60 j = 1, k1
|
||||
ll = ll + 1
|
||||
sp = sp + c(ll)*h(j)
|
||||
60 continue
|
||||
y(i) = sp
|
||||
80 continue
|
||||
100 return
|
||||
end
|
||||
62
cxx/fitpack/splint.f
Normal file
62
cxx/fitpack/splint.f
Normal file
@ -0,0 +1,62 @@
|
||||
recursive function splint(t,n,c,nc,k,a,b,wrk) result(splint_res)
|
||||
implicit none
|
||||
real*8 :: splint_res
|
||||
c function splint calculates the integral of a spline function s(x)
|
||||
c of degree k, which is given in its normalized b-spline representation
|
||||
c
|
||||
c calling sequence:
|
||||
c aint = splint(t,n,c,k,a,b,wrk)
|
||||
c
|
||||
c input parameters:
|
||||
c t : array,length n,which contains the position of the knots
|
||||
c of s(x).
|
||||
c n : integer, giving the total number of knots of s(x).
|
||||
c c : array,length nc, containing the b-spline coefficients.
|
||||
c the length of the array, nc >= n - k -1.
|
||||
c further coefficients are ignored.
|
||||
c k : integer, giving the degree of s(x).
|
||||
c a,b : real values, containing the end points of the integration
|
||||
c interval. s(x) is considered to be identically zero outside
|
||||
c the interval (t(k+1),t(n-k)).
|
||||
c
|
||||
c output parameter:
|
||||
c aint : real, containing the integral of s(x) between a and b.
|
||||
c wrk : real array, length n. used as working space
|
||||
c on output, wrk will contain the integrals of the normalized
|
||||
c b-splines defined on the set of knots.
|
||||
c
|
||||
c other subroutines required: fpintb.
|
||||
c
|
||||
c references :
|
||||
c gaffney p.w. : the calculation of indefinite integrals of b-splines
|
||||
c j. inst. maths applics 17 (1976) 37-41.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..scalar arguments..
|
||||
real*8 a,b
|
||||
integer n,k, nc
|
||||
c ..array arguments..
|
||||
real*8 t(n),c(nc),wrk(n)
|
||||
c ..local scalars..
|
||||
integer i,nk1
|
||||
c ..
|
||||
nk1 = n-k-1
|
||||
c calculate the integrals wrk(i) of the normalized b-splines
|
||||
c ni,k+1(x), i=1,2,...nk1.
|
||||
call fpintb(t,n,wrk,nk1,a,b)
|
||||
c calculate the integral of s(x).
|
||||
splint_res = 0.0d0
|
||||
do 10 i=1,nk1
|
||||
splint_res = splint_res+c(i)*wrk(i)
|
||||
10 continue
|
||||
return
|
||||
end
|
||||
186
cxx/fitpack/sproot.f
Normal file
186
cxx/fitpack/sproot.f
Normal file
@ -0,0 +1,186 @@
|
||||
recursive subroutine sproot(t,n,c,nc,zero,mest,m,ier)
|
||||
implicit none
|
||||
c subroutine sproot finds the zeros of a cubic spline s(x),which is
|
||||
c given in its normalized b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c call sproot(t,n,c,nc,zero,mest,m,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c t : real array,length n, containing the knots of s(x).
|
||||
c n : integer, containing the number of knots. n>=8
|
||||
c c : array,length nc, containing the b-spline coefficients.
|
||||
c the length of the array, nc >= n - k -1.
|
||||
c further coefficients are ignored.
|
||||
c mest : integer, specifying the dimension of array zero.
|
||||
c
|
||||
c output parameters:
|
||||
c zero : real array,length mest, containing the zeros of s(x).
|
||||
c m : integer,giving the number of zeros.
|
||||
c ier : error flag:
|
||||
c ier = 0: normal return.
|
||||
c ier = 1: the number of zeros exceeds mest.
|
||||
c ier =10: invalid input data (see restrictions).
|
||||
c
|
||||
c other subroutines required: fpcuro
|
||||
c
|
||||
c restrictions:
|
||||
c 1) n>= 8.
|
||||
c 2) t(4) < t(5) < ... < t(n-4) < t(n-3).
|
||||
c t(1) <= t(2) <= t(3) <= t(4)
|
||||
c t(n-3) <= t(n-2) <= t(n-1) <= t(n)
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
integer n,nc,mest,m,ier
|
||||
c ..array arguments..
|
||||
real*8 t(n),c(nc),zero(mest)
|
||||
c ..local scalars..
|
||||
integer i,j,j1,l,n4
|
||||
real*8 ah,a0,a1,a2,a3,bh,b0,b1,c1,c2,c3,c4,c5,d4,d5,h1,h2,
|
||||
* three,two,t1,t2,t3,t4,t5,zz
|
||||
logical z0,z1,z2,z3,z4,nz0,nz1,nz2,nz3,nz4
|
||||
c ..local array..
|
||||
real*8 y(3)
|
||||
c ..
|
||||
c set some constants
|
||||
two = 0.2d+01
|
||||
three = 0.3d+01
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid, control is immediately repassed to the calling program.
|
||||
n4 = n-4
|
||||
ier = 10
|
||||
if(n.lt.8) go to 800
|
||||
j = n
|
||||
do 10 i=1,3
|
||||
if(t(i).gt.t(i+1)) go to 800
|
||||
if(t(j).lt.t(j-1)) go to 800
|
||||
j = j-1
|
||||
10 continue
|
||||
do 20 i=4,n4
|
||||
if(t(i).ge.t(i+1)) go to 800
|
||||
20 continue
|
||||
c the problem considered reduces to finding the zeros of the cubic
|
||||
c polynomials pl(x) which define the cubic spline in each knot
|
||||
c interval t(l)<=x<=t(l+1). a zero of pl(x) is also a zero of s(x) on
|
||||
c the condition that it belongs to the knot interval.
|
||||
c the cubic polynomial pl(x) is determined by computing s(t(l)),
|
||||
c s'(t(l)),s(t(l+1)) and s'(t(l+1)). in fact we only have to compute
|
||||
c s(t(l+1)) and s'(t(l+1)); because of the continuity conditions of
|
||||
c splines and their derivatives, the value of s(t(l)) and s'(t(l))
|
||||
c is already known from the foregoing knot interval.
|
||||
ier = 0
|
||||
c evaluate some constants for the first knot interval
|
||||
h1 = t(4)-t(3)
|
||||
h2 = t(5)-t(4)
|
||||
t1 = t(4)-t(2)
|
||||
t2 = t(5)-t(3)
|
||||
t3 = t(6)-t(4)
|
||||
t4 = t(5)-t(2)
|
||||
t5 = t(6)-t(3)
|
||||
c calculate a0 = s(t(4)) and ah = s'(t(4)).
|
||||
c1 = c(1)
|
||||
c2 = c(2)
|
||||
c3 = c(3)
|
||||
c4 = (c2-c1)/t4
|
||||
c5 = (c3-c2)/t5
|
||||
d4 = (h2*c1+t1*c2)/t4
|
||||
d5 = (t3*c2+h1*c3)/t5
|
||||
a0 = (h2*d4+h1*d5)/t2
|
||||
ah = three*(h2*c4+h1*c5)/t2
|
||||
z1 = .true.
|
||||
if(ah.lt.0.0d0) z1 = .false.
|
||||
nz1 = .not.z1
|
||||
m = 0
|
||||
c main loop for the different knot intervals.
|
||||
do 300 l=4,n4
|
||||
c evaluate some constants for the knot interval t(l) <= x <= t(l+1).
|
||||
h1 = h2
|
||||
h2 = t(l+2)-t(l+1)
|
||||
t1 = t2
|
||||
t2 = t3
|
||||
t3 = t(l+3)-t(l+1)
|
||||
t4 = t5
|
||||
t5 = t(l+3)-t(l)
|
||||
c find a0 = s(t(l)), ah = s'(t(l)), b0 = s(t(l+1)) and bh = s'(t(l+1)).
|
||||
c1 = c2
|
||||
c2 = c3
|
||||
c3 = c(l)
|
||||
c4 = c5
|
||||
c5 = (c3-c2)/t5
|
||||
d4 = (h2*c1+t1*c2)/t4
|
||||
d5 = (h1*c3+t3*c2)/t5
|
||||
b0 = (h2*d4+h1*d5)/t2
|
||||
bh = three*(h2*c4+h1*c5)/t2
|
||||
c calculate the coefficients a0,a1,a2 and a3 of the cubic polynomial
|
||||
c pl(x) = ql(y) = a0+a1*y+a2*y**2+a3*y**3 ; y = (x-t(l))/(t(l+1)-t(l)).
|
||||
a1 = ah*h1
|
||||
b1 = bh*h1
|
||||
a2 = three*(b0-a0)-b1-two*a1
|
||||
a3 = two*(a0-b0)+b1+a1
|
||||
c test whether or not pl(x) could have a zero in the range
|
||||
c t(l) <= x <= t(l+1).
|
||||
z3 = .true.
|
||||
if(b1.lt.0.0d0) z3 = .false.
|
||||
nz3 = .not.z3
|
||||
if(a0*b0.le.0.0d0) go to 100
|
||||
z0 = .true.
|
||||
if(a0.lt.0.0d0) z0 = .false.
|
||||
nz0 = .not.z0
|
||||
z2 = .true.
|
||||
if(a2.lt.0.) z2 = .false.
|
||||
nz2 = .not.z2
|
||||
z4 = .true.
|
||||
if(3.0d0*a3+a2.lt.0.0d0) z4 = .false.
|
||||
nz4 = .not.z4
|
||||
if(.not.((z0.and.(nz1.and.(z3.or.z2.and.nz4).or.nz2.and.
|
||||
* z3.and.z4).or.nz0.and.(z1.and.(nz3.or.nz2.and.z4).or.z2.and.
|
||||
* nz3.and.nz4))))go to 200
|
||||
c find the zeros of ql(y).
|
||||
100 call fpcuro(a3,a2,a1,a0,y,j)
|
||||
if(j.eq.0) go to 200
|
||||
c find which zeros of pl(x) are zeros of s(x).
|
||||
do 150 i=1,j
|
||||
if(y(i).lt.0.0d0 .or. y(i).gt.1.0d0) go to 150
|
||||
c test whether the number of zeros of s(x) exceeds mest.
|
||||
if(m.ge.mest) go to 700
|
||||
m = m+1
|
||||
zero(m) = t(l)+h1*y(i)
|
||||
150 continue
|
||||
200 a0 = b0
|
||||
ah = bh
|
||||
z1 = z3
|
||||
nz1 = nz3
|
||||
300 continue
|
||||
c the zeros of s(x) are arranged in increasing order.
|
||||
if(m.lt.2) go to 800
|
||||
do 400 i=2,m
|
||||
j = i
|
||||
350 j1 = j-1
|
||||
if(j1.eq.0) go to 400
|
||||
if(zero(j).ge.zero(j1)) go to 400
|
||||
zz = zero(j)
|
||||
zero(j) = zero(j1)
|
||||
zero(j1) = zz
|
||||
j = j1
|
||||
go to 350
|
||||
400 continue
|
||||
j = m
|
||||
m = 1
|
||||
do 500 i=2,j
|
||||
if(zero(i).eq.zero(m)) go to 500
|
||||
m = m+1
|
||||
zero(m) = zero(i)
|
||||
500 continue
|
||||
go to 800
|
||||
700 ier = 1
|
||||
800 return
|
||||
end
|
||||
107
cxx/fitpack/surev.f
Normal file
107
cxx/fitpack/surev.f
Normal file
@ -0,0 +1,107 @@
|
||||
recursive subroutine surev(idim,tu,nu,tv,nv,c,u,mu,v,mv,f,mf,
|
||||
* wrk,lwrk,iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c subroutine surev evaluates on a grid (u(i),v(j)),i=1,...,mu; j=1,...
|
||||
c ,mv a bicubic spline surface of dimension idim, given in the
|
||||
c b-spline representation.
|
||||
c
|
||||
c calling sequence:
|
||||
c call surev(idim,tu,nu,tv,nv,c,u,mu,v,mv,f,mf,wrk,lwrk,
|
||||
c * iwrk,kwrk,ier)
|
||||
c
|
||||
c input parameters:
|
||||
c idim : integer, specifying the dimension of the spline surface.
|
||||
c tu : real array, length nu, which contains the position of the
|
||||
c knots in the u-direction.
|
||||
c nu : integer, giving the total number of knots in the u-direction
|
||||
c tv : real array, length nv, which contains the position of the
|
||||
c knots in the v-direction.
|
||||
c nv : integer, giving the total number of knots in the v-direction
|
||||
c c : real array, length (nu-4)*(nv-4)*idim, which contains the
|
||||
c b-spline coefficients.
|
||||
c u : real array of dimension (mu).
|
||||
c before entry u(i) must be set to the u co-ordinate of the
|
||||
c i-th grid point along the u-axis.
|
||||
c tu(4)<=u(i-1)<=u(i)<=tu(nu-3), i=2,...,mu.
|
||||
c mu : on entry mu must specify the number of grid points along
|
||||
c the u-axis. mu >=1.
|
||||
c v : real array of dimension (mv).
|
||||
c before entry v(j) must be set to the v co-ordinate of the
|
||||
c j-th grid point along the v-axis.
|
||||
c tv(4)<=v(j-1)<=v(j)<=tv(nv-3), j=2,...,mv.
|
||||
c mv : on entry mv must specify the number of grid points along
|
||||
c the v-axis. mv >=1.
|
||||
c mf : on entry, mf must specify the dimension of the array f.
|
||||
c mf >= mu*mv*idim
|
||||
c wrk : real array of dimension lwrk. used as workspace.
|
||||
c lwrk : integer, specifying the dimension of wrk.
|
||||
c lwrk >= 4*(mu+mv)
|
||||
c iwrk : integer array of dimension kwrk. used as workspace.
|
||||
c kwrk : integer, specifying the dimension of iwrk. kwrk >= mu+mv.
|
||||
c
|
||||
c output parameters:
|
||||
c f : real array of dimension (mf).
|
||||
c on successful exit f(mu*mv*(l-1)+mv*(i-1)+j) contains the
|
||||
c l-th co-ordinate of the bicubic spline surface at the
|
||||
c point (u(i),v(j)),l=1,...,idim,i=1,...,mu;j=1,...,mv.
|
||||
c ier : integer error flag
|
||||
c ier=0 : normal return
|
||||
c ier=10: invalid input data (see restrictions)
|
||||
c
|
||||
c restrictions:
|
||||
c mu >=1, mv >=1, lwrk>=4*(mu+mv), kwrk>=mu+mv , mf>=mu*mv*idim
|
||||
c tu(4) <= u(i-1) <= u(i) <= tu(nu-3), i=2,...,mu
|
||||
c tv(4) <= v(j-1) <= v(j) <= tv(nv-3), j=2,...,mv
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpsuev,fpbspl
|
||||
c
|
||||
c references :
|
||||
c de boor c : on calculating with b-splines, j. approximation theory
|
||||
c 6 (1972) 50-62.
|
||||
c cox m.g. : the numerical evaluation of b-splines, j. inst. maths
|
||||
c applics 10 (1972) 134-149.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author :
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u.leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..scalar arguments..
|
||||
integer idim,nu,nv,mu,mv,mf,lwrk,kwrk,ier
|
||||
c ..array arguments..
|
||||
integer iwrk(kwrk)
|
||||
real*8 tu(nu),tv(nv),c((nu-4)*(nv-4)*idim),u(mu),v(mv),f(mf),
|
||||
* wrk(lwrk)
|
||||
c ..local scalars..
|
||||
integer i,muv
|
||||
c ..
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(mf.lt.mu*mv*idim) go to 100
|
||||
muv = mu+mv
|
||||
if(lwrk.lt.4*muv) go to 100
|
||||
if(kwrk.lt.muv) go to 100
|
||||
if (mu.lt.1) go to 100
|
||||
if (mu.eq.1) go to 30
|
||||
go to 10
|
||||
10 do 20 i=2,mu
|
||||
if(u(i).lt.u(i-1)) go to 100
|
||||
20 continue
|
||||
30 if (mv.lt.1) go to 100
|
||||
if (mv.eq.1) go to 60
|
||||
go to 40
|
||||
40 do 50 i=2,mv
|
||||
if(v(i).lt.v(i-1)) go to 100
|
||||
50 continue
|
||||
60 ier = 0
|
||||
call fpsuev(idim,tu,nu,tv,nv,c,u,mu,v,mv,f,wrk(1),wrk(4*mu+1),
|
||||
* iwrk(1),iwrk(mu+1))
|
||||
100 return
|
||||
end
|
||||
414
cxx/fitpack/surfit.f
Normal file
414
cxx/fitpack/surfit.f
Normal file
@ -0,0 +1,414 @@
|
||||
recursive subroutine surfit(iopt,m,x,y,z,w,xb,xe,yb,ye,kx,ky,s,
|
||||
* nxest,nyest,nmax,eps,nx,tx,ny,ty,c,fp,wrk1,lwrk1,wrk2,lwrk2,
|
||||
* iwrk,kwrk,ier)
|
||||
implicit none
|
||||
c given the set of data points (x(i),y(i),z(i)) and the set of positive
|
||||
c numbers w(i),i=1,...,m, subroutine surfit determines a smooth bivar-
|
||||
c iate spline approximation s(x,y) of degrees kx and ky on the rect-
|
||||
c angle xb <= x <= xe, yb <= y <= ye.
|
||||
c if iopt = -1 surfit calculates the weighted least-squares spline
|
||||
c according to a given set of knots.
|
||||
c if iopt >= 0 the total numbers nx and ny of these knots and their
|
||||
c position tx(j),j=1,...,nx and ty(j),j=1,...,ny are chosen automatic-
|
||||
c ally by the routine. the smoothness of s(x,y) is then achieved by
|
||||
c minimalizing the discontinuity jumps in the derivatives of s(x,y)
|
||||
c across the boundaries of the subpanels (tx(i),tx(i+1))*(ty(j),ty(j+1).
|
||||
c the amounth of smoothness is determined by the condition that f(p) =
|
||||
c sum ((w(i)*(z(i)-s(x(i),y(i))))**2) be <= s, with s a given non-neg-
|
||||
c ative constant, called the smoothing factor.
|
||||
c the fit is given in the b-spline representation (b-spline coefficients
|
||||
c c((ny-ky-1)*(i-1)+j),i=1,...,nx-kx-1;j=1,...,ny-ky-1) and can be eval-
|
||||
c uated by means of subroutine bispev.
|
||||
c
|
||||
c calling sequence:
|
||||
c call surfit(iopt,m,x,y,z,w,xb,xe,yb,ye,kx,ky,s,nxest,nyest,
|
||||
c * nmax,eps,nx,tx,ny,ty,c,fp,wrk1,lwrk1,wrk2,lwrk2,iwrk,kwrk,ier)
|
||||
c
|
||||
c parameters:
|
||||
c iopt : integer flag. on entry iopt must specify whether a weighted
|
||||
c least-squares spline (iopt=-1) or a smoothing spline (iopt=0
|
||||
c or 1) must be determined.
|
||||
c if iopt=0 the routine will start with an initial set of knots
|
||||
c tx(i)=xb,tx(i+kx+1)=xe,i=1,...,kx+1;ty(i)=yb,ty(i+ky+1)=ye,i=
|
||||
c 1,...,ky+1. if iopt=1 the routine will continue with the set
|
||||
c of knots found at the last call of the routine.
|
||||
c attention: a call with iopt=1 must always be immediately pre-
|
||||
c ceded by another call with iopt=1 or iopt=0.
|
||||
c unchanged on exit.
|
||||
c m : integer. on entry m must specify the number of data points.
|
||||
c m >= (kx+1)*(ky+1). unchanged on exit.
|
||||
c x : real array of dimension at least (m).
|
||||
c y : real array of dimension at least (m).
|
||||
c z : real array of dimension at least (m).
|
||||
c before entry, x(i),y(i),z(i) must be set to the co-ordinates
|
||||
c of the i-th data point, for i=1,...,m. the order of the data
|
||||
c points is immaterial. unchanged on exit.
|
||||
c w : real array of dimension at least (m). before entry, w(i) must
|
||||
c be set to the i-th value in the set of weights. the w(i) must
|
||||
c be strictly positive. unchanged on exit.
|
||||
c xb,xe : real values. on entry xb,xe,yb and ye must specify the bound-
|
||||
c yb,ye aries of the rectangular approximation domain.
|
||||
c xb<=x(i)<=xe,yb<=y(i)<=ye,i=1,...,m. unchanged on exit.
|
||||
c kx,ky : integer values. on entry kx and ky must specify the degrees
|
||||
c of the spline. 1<=kx,ky<=5. it is recommended to use bicubic
|
||||
c (kx=ky=3) splines. unchanged on exit.
|
||||
c s : real. on entry (in case iopt>=0) s must specify the smoothing
|
||||
c factor. s >=0. unchanged on exit.
|
||||
c for advice on the choice of s see further comments
|
||||
c nxest : integer. unchanged on exit.
|
||||
c nyest : integer. unchanged on exit.
|
||||
c on entry, nxest and nyest must specify an upper bound for the
|
||||
c number of knots required in the x- and y-directions respect.
|
||||
c these numbers will also determine the storage space needed by
|
||||
c the routine. nxest >= 2*(kx+1), nyest >= 2*(ky+1).
|
||||
c in most practical situation nxest = kx+1+sqrt(m/2), nyest =
|
||||
c ky+1+sqrt(m/2) will be sufficient. see also further comments.
|
||||
c nmax : integer. on entry nmax must specify the actual dimension of
|
||||
c the arrays tx and ty. nmax >= nxest, nmax >=nyest.
|
||||
c unchanged on exit.
|
||||
c eps : real.
|
||||
c on entry, eps must specify a threshold for determining the
|
||||
c effective rank of an over-determined linear system of equat-
|
||||
c ions. 0 < eps < 1. if the number of decimal digits in the
|
||||
c computer representation of a real number is q, then 10**(-q)
|
||||
c is a suitable value for eps in most practical applications.
|
||||
c unchanged on exit.
|
||||
c nx : integer.
|
||||
c unless ier=10 (in case iopt >=0), nx will contain the total
|
||||
c number of knots with respect to the x-variable, of the spline
|
||||
c approximation returned. if the computation mode iopt=1 is
|
||||
c used, the value of nx should be left unchanged between sub-
|
||||
c sequent calls.
|
||||
c in case iopt=-1, the value of nx should be specified on entry
|
||||
c tx : real array of dimension nmax.
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline with respect to the x-variable, i.e. the position of
|
||||
c the interior knots tx(kx+2),...,tx(nx-kx-1) as well as the
|
||||
c position of the additional knots tx(1)=...=tx(kx+1)=xb and
|
||||
c tx(nx-kx)=...=tx(nx)=xe needed for the b-spline representat.
|
||||
c if the computation mode iopt=1 is used, the values of tx(1),
|
||||
c ...,tx(nx) should be left unchanged between subsequent calls.
|
||||
c if the computation mode iopt=-1 is used, the values tx(kx+2),
|
||||
c ...tx(nx-kx-1) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c ny : integer.
|
||||
c unless ier=10 (in case iopt >=0), ny will contain the total
|
||||
c number of knots with respect to the y-variable, of the spline
|
||||
c approximation returned. if the computation mode iopt=1 is
|
||||
c used, the value of ny should be left unchanged between sub-
|
||||
c sequent calls.
|
||||
c in case iopt=-1, the value of ny should be specified on entry
|
||||
c ty : real array of dimension nmax.
|
||||
c on successful exit, this array will contain the knots of the
|
||||
c spline with respect to the y-variable, i.e. the position of
|
||||
c the interior knots ty(ky+2),...,ty(ny-ky-1) as well as the
|
||||
c position of the additional knots ty(1)=...=ty(ky+1)=yb and
|
||||
c ty(ny-ky)=...=ty(ny)=ye needed for the b-spline representat.
|
||||
c if the computation mode iopt=1 is used, the values of ty(1),
|
||||
c ...,ty(ny) should be left unchanged between subsequent calls.
|
||||
c if the computation mode iopt=-1 is used, the values ty(ky+2),
|
||||
c ...ty(ny-ky-1) must be supplied by the user, before entry.
|
||||
c see also the restrictions (ier=10).
|
||||
c c : real array of dimension at least (nxest-kx-1)*(nyest-ky-1).
|
||||
c on successful exit, c contains the coefficients of the spline
|
||||
c approximation s(x,y)
|
||||
c fp : real. unless ier=10, fp contains the weighted sum of
|
||||
c squared residuals of the spline approximation returned.
|
||||
c wrk1 : real array of dimension (lwrk1). used as workspace.
|
||||
c if the computation mode iopt=1 is used the value of wrk1(1)
|
||||
c should be left unchanged between subsequent calls.
|
||||
c on exit wrk1(2),wrk1(3),...,wrk1(1+(nx-kx-1)*(ny-ky-1)) will
|
||||
c contain the values d(i)/max(d(i)),i=1,...,(nx-kx-1)*(ny-ky-1)
|
||||
c with d(i) the i-th diagonal element of the reduced triangular
|
||||
c matrix for calculating the b-spline coefficients. it includes
|
||||
c those elements whose square is less than eps,which are treat-
|
||||
c ed as 0 in the case of presumed rank deficiency (ier<-2).
|
||||
c lwrk1 : integer. on entry lwrk1 must specify the actual dimension of
|
||||
c the array wrk1 as declared in the calling (sub)program.
|
||||
c lwrk1 must not be too small. let
|
||||
c u = nxest-kx-1, v = nyest-ky-1, km = max(kx,ky)+1,
|
||||
c ne = max(nxest,nyest), bx = kx*v+ky+1, by = ky*u+kx+1,
|
||||
c if(bx.le.by) b1 = bx, b2 = b1+v-ky
|
||||
c if(bx.gt.by) b1 = by, b2 = b1+u-kx then
|
||||
c lwrk1 >= u*v*(2+b1+b2)+2*(u+v+km*(m+ne)+ne-kx-ky)+b2+1
|
||||
c wrk2 : real array of dimension (lwrk2). used as workspace, but
|
||||
c only in the case a rank deficient system is encountered.
|
||||
c lwrk2 : integer. on entry lwrk2 must specify the actual dimension of
|
||||
c the array wrk2 as declared in the calling (sub)program.
|
||||
c lwrk2 > 0 . a save upper boundfor lwrk2 = u*v*(b2+1)+b2
|
||||
c where u,v and b2 are as above. if there are enough data
|
||||
c points, scattered uniformly over the approximation domain
|
||||
c and if the smoothing factor s is not too small, there is a
|
||||
c good chance that this extra workspace is not needed. a lot
|
||||
c of memory might therefore be saved by setting lwrk2=1.
|
||||
c (see also ier > 10)
|
||||
c iwrk : integer array of dimension (kwrk). used as workspace.
|
||||
c kwrk : integer. on entry kwrk must specify the actual dimension of
|
||||
c the array iwrk as declared in the calling (sub)program.
|
||||
c kwrk >= m+(nxest-2*kx-1)*(nyest-2*ky-1).
|
||||
c ier : integer. unless the routine detects an error, ier contains a
|
||||
c non-positive value on exit, i.e.
|
||||
c ier=0 : normal return. the spline returned has a residual sum of
|
||||
c squares fp such that abs(fp-s)/s <= tol with tol a relat-
|
||||
c ive tolerance set to 0.001 by the program.
|
||||
c ier=-1 : normal return. the spline returned is an interpolating
|
||||
c spline (fp=0).
|
||||
c ier=-2 : normal return. the spline returned is the weighted least-
|
||||
c squares polynomial of degrees kx and ky. in this extreme
|
||||
c case fp gives the upper bound for the smoothing factor s.
|
||||
c ier<-2 : warning. the coefficients of the spline returned have been
|
||||
c computed as the minimal norm least-squares solution of a
|
||||
c (numerically) rank deficient system. (-ier) gives the rank.
|
||||
c especially if the rank deficiency which can be computed as
|
||||
c (nx-kx-1)*(ny-ky-1)+ier, is large the results may be inac-
|
||||
c curate. they could also seriously depend on the value of
|
||||
c eps.
|
||||
c ier=1 : error. the required storage space exceeds the available
|
||||
c storage space, as specified by the parameters nxest and
|
||||
c nyest.
|
||||
c probably causes : nxest or nyest too small. if these param-
|
||||
c eters are already large, it may also indicate that s is
|
||||
c too small
|
||||
c the approximation returned is the weighted least-squares
|
||||
c spline according to the current set of knots.
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=2 : error. a theoretically impossible result was found during
|
||||
c the iteration process for finding a smoothing spline with
|
||||
c fp = s. probably causes : s too small or badly chosen eps.
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=3 : error. the maximal number of iterations maxit (set to 20
|
||||
c by the program) allowed for finding a smoothing spline
|
||||
c with fp=s has been reached. probably causes : s too small
|
||||
c there is an approximation returned but the corresponding
|
||||
c weighted sum of squared residuals does not satisfy the
|
||||
c condition abs(fp-s)/s < tol.
|
||||
c ier=4 : error. no more knots can be added because the number of
|
||||
c b-spline coefficients (nx-kx-1)*(ny-ky-1) already exceeds
|
||||
c the number of data points m.
|
||||
c probably causes : either s or m too small.
|
||||
c the approximation returned is the weighted least-squares
|
||||
c spline according to the current set of knots.
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=5 : error. no more knots can be added because the additional
|
||||
c knot would (quasi) coincide with an old one.
|
||||
c probably causes : s too small or too large a weight to an
|
||||
c inaccurate data point.
|
||||
c the approximation returned is the weighted least-squares
|
||||
c spline according to the current set of knots.
|
||||
c the parameter fp gives the corresponding weighted sum of
|
||||
c squared residuals (fp>s).
|
||||
c ier=10 : error. on entry, the input data are controlled on validity
|
||||
c the following restrictions must be satisfied.
|
||||
c -1<=iopt<=1, 1<=kx,ky<=5, m>=(kx+1)*(ky+1), nxest>=2*kx+2,
|
||||
c nyest>=2*ky+2, 0<eps<1, nmax>=nxest, nmax>=nyest,
|
||||
c xb<=x(i)<=xe, yb<=y(i)<=ye, w(i)>0, i=1,...,m
|
||||
c lwrk1 >= u*v*(2+b1+b2)+2*(u+v+km*(m+ne)+ne-kx-ky)+b2+1
|
||||
c kwrk >= m+(nxest-2*kx-1)*(nyest-2*ky-1)
|
||||
c if iopt=-1: 2*kx+2<=nx<=nxest
|
||||
c xb<tx(kx+2)<tx(kx+3)<...<tx(nx-kx-1)<xe
|
||||
c 2*ky+2<=ny<=nyest
|
||||
c yb<ty(ky+2)<ty(ky+3)<...<ty(ny-ky-1)<ye
|
||||
c if iopt>=0: s>=0
|
||||
c if one of these conditions is found to be violated,control
|
||||
c is immediately repassed to the calling program. in that
|
||||
c case there is no approximation returned.
|
||||
c ier>10 : error. lwrk2 is too small, i.e. there is not enough work-
|
||||
c space for computing the minimal least-squares solution of
|
||||
c a rank deficient system of linear equations. ier gives the
|
||||
c requested value for lwrk2. there is no approximation re-
|
||||
c turned but, having saved the information contained in nx,
|
||||
c ny,tx,ty,wrk1, and having adjusted the value of lwrk2 and
|
||||
c the dimension of the array wrk2 accordingly, the user can
|
||||
c continue at the point the program was left, by calling
|
||||
c surfit with iopt=1.
|
||||
c
|
||||
c further comments:
|
||||
c by means of the parameter s, the user can control the tradeoff
|
||||
c between closeness of fit and smoothness of fit of the approximation.
|
||||
c if s is too large, the spline will be too smooth and signal will be
|
||||
c lost ; if s is too small the spline will pick up too much noise. in
|
||||
c the extreme cases the program will return an interpolating spline if
|
||||
c s=0 and the weighted least-squares polynomial (degrees kx,ky)if s is
|
||||
c very large. between these extremes, a properly chosen s will result
|
||||
c in a good compromise between closeness of fit and smoothness of fit.
|
||||
c to decide whether an approximation, corresponding to a certain s is
|
||||
c satisfactory the user is highly recommended to inspect the fits
|
||||
c graphically.
|
||||
c recommended values for s depend on the weights w(i). if these are
|
||||
c taken as 1/d(i) with d(i) an estimate of the standard deviation of
|
||||
c z(i), a good s-value should be found in the range (m-sqrt(2*m),m+
|
||||
c sqrt(2*m)). if nothing is known about the statistical error in z(i)
|
||||
c each w(i) can be set equal to one and s determined by trial and
|
||||
c error, taking account of the comments above. the best is then to
|
||||
c start with a very large value of s ( to determine the least-squares
|
||||
c polynomial and the corresponding upper bound fp0 for s) and then to
|
||||
c progressively decrease the value of s ( say by a factor 10 in the
|
||||
c beginning, i.e. s=fp0/10, fp0/100,...and more carefully as the
|
||||
c approximation shows more detail) to obtain closer fits.
|
||||
c to choose s very small is strongly discouraged. this considerably
|
||||
c increases computation time and memory requirements. it may also
|
||||
c cause rank-deficiency (ier<-2) and endager numerical stability.
|
||||
c to economize the search for a good s-value the program provides with
|
||||
c different modes of computation. at the first call of the routine, or
|
||||
c whenever he wants to restart with the initial set of knots the user
|
||||
c must set iopt=0.
|
||||
c if iopt=1 the program will continue with the set of knots found at
|
||||
c the last call of the routine. this will save a lot of computation
|
||||
c time if surfit is called repeatedly for different values of s.
|
||||
c the number of knots of the spline returned and their location will
|
||||
c depend on the value of s and on the complexity of the shape of the
|
||||
c function underlying the data. if the computation mode iopt=1
|
||||
c is used, the knots returned may also depend on the s-values at
|
||||
c previous calls (if these were smaller). therefore, if after a number
|
||||
c of trials with different s-values and iopt=1, the user can finally
|
||||
c accept a fit as satisfactory, it may be worthwhile for him to call
|
||||
c surfit once more with the selected value for s but now with iopt=0.
|
||||
c indeed, surfit may then return an approximation of the same quality
|
||||
c of fit but with fewer knots and therefore better if data reduction
|
||||
c is also an important objective for the user.
|
||||
c the number of knots may also depend on the upper bounds nxest and
|
||||
c nyest. indeed, if at a certain stage in surfit the number of knots
|
||||
c in one direction (say nx) has reached the value of its upper bound
|
||||
c (nxest), then from that moment on all subsequent knots are added
|
||||
c in the other (y) direction. this may indicate that the value of
|
||||
c nxest is too small. on the other hand, it gives the user the option
|
||||
c of limiting the number of knots the routine locates in any direction
|
||||
c for example, by setting nxest=2*kx+2 (the lowest allowable value for
|
||||
c nxest), the user can indicate that he wants an approximation which
|
||||
c is a simple polynomial of degree kx in the variable x.
|
||||
c
|
||||
c other subroutines required:
|
||||
c fpback,fpbspl,fpsurf,fpdisc,fpgivs,fprank,fprati,fprota,fporde
|
||||
c
|
||||
c references:
|
||||
c dierckx p. : an algorithm for surface fitting with spline functions
|
||||
c ima j. numer. anal. 1 (1981) 267-283.
|
||||
c dierckx p. : an algorithm for surface fitting with spline functions
|
||||
c report tw50, dept. computer science,k.u.leuven, 1980.
|
||||
c dierckx p. : curve and surface fitting with splines, monographs on
|
||||
c numerical analysis, oxford university press, 1993.
|
||||
c
|
||||
c author:
|
||||
c p.dierckx
|
||||
c dept. computer science, k.u. leuven
|
||||
c celestijnenlaan 200a, b-3001 heverlee, belgium.
|
||||
c e-mail : Paul.Dierckx@cs.kuleuven.ac.be
|
||||
c
|
||||
c creation date : may 1979
|
||||
c latest update : march 1987
|
||||
c
|
||||
c ..
|
||||
c ..scalar arguments..
|
||||
real*8 xb,xe,yb,ye,s,eps,fp
|
||||
integer iopt,m,kx,ky,nxest,nyest,nmax,nx,ny,lwrk1,lwrk2,kwrk,ier
|
||||
c ..array arguments..
|
||||
real*8 x(m),y(m),z(m),w(m),tx(nmax),ty(nmax),
|
||||
* c((nxest-kx-1)*(nyest-ky-1)),wrk1(lwrk1),wrk2(lwrk2)
|
||||
integer iwrk(kwrk)
|
||||
c ..local scalars..
|
||||
real*8 tol
|
||||
integer i,ib1,ib3,jb1,ki,kmax,km1,km2,kn,kwest,kx1,ky1,la,lbx,
|
||||
* lby,lco,lf,lff,lfp,lh,lq,lsx,lsy,lwest,maxit,ncest,nest,nek,
|
||||
* nminx,nminy,nmx,nmy,nreg,nrint,nxk,nyk
|
||||
c ..function references..
|
||||
integer max0
|
||||
c ..subroutine references..
|
||||
c fpsurf
|
||||
c ..
|
||||
c we set up the parameters tol and maxit.
|
||||
maxit = 20
|
||||
tol = 0.1e-02
|
||||
c before starting computations a data check is made. if the input data
|
||||
c are invalid,control is immediately repassed to the calling program.
|
||||
ier = 10
|
||||
if(eps.le.0. .or. eps.ge.1.) go to 71
|
||||
if(kx.le.0 .or. kx.gt.5) go to 71
|
||||
kx1 = kx+1
|
||||
if(ky.le.0 .or. ky.gt.5) go to 71
|
||||
ky1 = ky+1
|
||||
kmax = max0(kx,ky)
|
||||
km1 = kmax+1
|
||||
km2 = km1+1
|
||||
if(iopt.lt.(-1) .or. iopt.gt.1) go to 71
|
||||
if(m.lt.(kx1*ky1)) go to 71
|
||||
nminx = 2*kx1
|
||||
if(nxest.lt.nminx .or. nxest.gt.nmax) go to 71
|
||||
nminy = 2*ky1
|
||||
if(nyest.lt.nminy .or. nyest.gt.nmax) go to 71
|
||||
nest = max0(nxest,nyest)
|
||||
nxk = nxest-kx1
|
||||
nyk = nyest-ky1
|
||||
ncest = nxk*nyk
|
||||
nmx = nxest-nminx+1
|
||||
nmy = nyest-nminy+1
|
||||
nrint = nmx+nmy
|
||||
nreg = nmx*nmy
|
||||
ib1 = kx*nyk+ky1
|
||||
jb1 = ky*nxk+kx1
|
||||
ib3 = kx1*nyk+1
|
||||
if(ib1.le.jb1) go to 10
|
||||
ib1 = jb1
|
||||
ib3 = ky1*nxk+1
|
||||
10 lwest = ncest*(2+ib1+ib3)+2*(nrint+nest*km2+m*km1)+ib3
|
||||
kwest = m+nreg
|
||||
if(lwrk1.lt.lwest .or. kwrk.lt.kwest) go to 71
|
||||
if(xb.ge.xe .or. yb.ge.ye) go to 71
|
||||
do 20 i=1,m
|
||||
if(w(i).le.0.) go to 70
|
||||
if(x(i).lt.xb .or. x(i).gt.xe) go to 71
|
||||
if(y(i).lt.yb .or. y(i).gt.ye) go to 71
|
||||
20 continue
|
||||
if(iopt.ge.0) go to 50
|
||||
if(nx.lt.nminx .or. nx.gt.nxest) go to 71
|
||||
nxk = nx-kx1
|
||||
tx(kx1) = xb
|
||||
tx(nxk+1) = xe
|
||||
do 30 i=kx1,nxk
|
||||
if(tx(i+1).le.tx(i)) go to 72
|
||||
30 continue
|
||||
if(ny.lt.nminy .or. ny.gt.nyest) go to 71
|
||||
nyk = ny-ky1
|
||||
ty(ky1) = yb
|
||||
ty(nyk+1) = ye
|
||||
do 40 i=ky1,nyk
|
||||
if(ty(i+1).le.ty(i)) go to 73
|
||||
40 continue
|
||||
go to 60
|
||||
50 if(s.lt.0.) go to 71
|
||||
60 ier = 0
|
||||
c we partition the working space and determine the spline approximation
|
||||
kn = 1
|
||||
ki = kn+m
|
||||
lq = 2
|
||||
la = lq+ncest*ib3
|
||||
lf = la+ncest*ib1
|
||||
lff = lf+ncest
|
||||
lfp = lff+ncest
|
||||
lco = lfp+nrint
|
||||
lh = lco+nrint
|
||||
lbx = lh+ib3
|
||||
nek = nest*km2
|
||||
lby = lbx+nek
|
||||
lsx = lby+nek
|
||||
lsy = lsx+m*km1
|
||||
call fpsurf(iopt,m,x,y,z,w,xb,xe,yb,ye,kx,ky,s,nxest,nyest,
|
||||
* eps,tol,maxit,nest,km1,km2,ib1,ib3,ncest,nrint,nreg,nx,tx,
|
||||
* ny,ty,c,fp,wrk1(1),wrk1(lfp),wrk1(lco),wrk1(lf),wrk1(lff),
|
||||
* wrk1(la),wrk1(lq),wrk1(lbx),wrk1(lby),wrk1(lsx),wrk1(lsy),
|
||||
* wrk1(lh),iwrk(ki),iwrk(kn),wrk2,lwrk2,ier)
|
||||
70 return
|
||||
71 print*,"iopt,kx,ky,m=",iopt,kx,ky,m
|
||||
print*,"nxest,nyest,nmax=",nxest,nyest,nmax
|
||||
print*,"lwrk1,lwrk2,kwrk=",lwrk1,lwrk2,kwrk
|
||||
print*,"xb,xe,yb,ye=",xb,xe,yb,ye
|
||||
print*,"eps,s",eps,s
|
||||
return
|
||||
72 print*,"tx=",tx
|
||||
return
|
||||
73 print*,"ty=",ty
|
||||
return
|
||||
end
|
||||
@ -78,7 +78,8 @@ int main(int argc, char* argv[])
|
||||
|
||||
logger->set_pattern("%v");
|
||||
int w = 90;
|
||||
const std::string fmt = std::format("{{:*^{}}}", w);
|
||||
// const std::string fmt = std::format("{{:*^{}}}", w);
|
||||
constexpr std::string_view fmt = "{{:*^90}}";
|
||||
logger->info("\n\n\n");
|
||||
logger->info(fmt, "");
|
||||
logger->info(fmt, " ASTROSIB BM700 MOUNT SERVER ");
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user