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slalib/vxv.f

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+      SUBROUTINE sla_VXV (VA, VB, VC)
+*+
+*     - - - -
+*      V X V
+*     - - - -
+*
+*  Vector product of two 3-vectors (single precision)
+*
+*  Given:
+*      VA      real(3)     first vector
+*      VB      real(3)     second vector
+*
+*  Returned:
+*      VC      real(3)     vector result
+*
+*  P.T.Wallace   Starlink   March 1986
+*
+*  Copyright (C) 1995 Rutherford Appleton Laboratory
+*
+*  License:
+*    This program is free software; you can redistribute it and/or modify
+*    it under the terms of the GNU General Public License as published by
+*    the Free Software Foundation; either version 2 of the License, or
+*    (at your option) any later version.
+*
+*    This program is distributed in the hope that it will be useful,
+*    but WITHOUT ANY WARRANTY; without even the implied warranty of
+*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*    GNU General Public License for more details.
+*
+*    You should have received a copy of the GNU General Public License
+*    along with this program (see SLA_CONDITIONS); if not, write to the 
+*    Free Software Foundation, Inc., 59 Temple Place, Suite 330, 
+*    Boston, MA  02111-1307  USA
+*
+*-
+
+      IMPLICIT NONE
+
+      REAL VA(3),VB(3),VC(3)
+
+      REAL VW(3)
+      INTEGER I
+
+
+*  Form the vector product VA cross VB
+      VW(1)=VA(2)*VB(3)-VA(3)*VB(2)
+      VW(2)=VA(3)*VB(1)-VA(1)*VB(3)
+      VW(3)=VA(1)*VB(2)-VA(2)*VB(1)
+
+*  Return the result
+      DO I=1,3
+         VC(I)=VW(I)
+      END DO
+
+      END