Timur A. Fatkhullin
5279d1c41a
start developing of FITPACK C++ bindings mount_server.cpp: fix compilation error with GCC15
33 lines
748 B
Fortran
33 lines
748 B
Fortran
recursive subroutine fpback(a,z,n,k,c,nest)
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implicit none
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c subroutine fpback calculates the solution of the system of
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c equations a*c = z with a a n x n upper triangular matrix
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c of bandwidth k.
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c ..
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c ..scalar arguments..
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integer n,k,nest
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c ..array arguments..
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real*8 a(nest,k),z(n),c(n)
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c ..local scalars..
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real*8 store
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integer i,i1,j,k1,l,m
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c ..
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k1 = k-1
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c(n) = z(n)/a(n,1)
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i = n-1
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if(i.eq.0) go to 30
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do 20 j=2,n
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store = z(i)
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i1 = k1
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if(j.le.k1) i1 = j-1
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m = i
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do 10 l=1,i1
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m = m+1
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store = store-c(m)*a(i,l+1)
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10 continue
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c(i) = store/a(i,1)
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i = i-1
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20 continue
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30 return
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end
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