From fa080de7afc95aa1c19a6e6fc0e0708ced2eadc4 Mon Sep 17 00:00:00 2001 From: Joseph Hunkeler Date: Wed, 8 Jul 2015 20:46:52 -0400 Subject: Initial commit --- math/slalib/mxv.f | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) create mode 100644 math/slalib/mxv.f (limited to 'math/slalib/mxv.f') diff --git a/math/slalib/mxv.f b/math/slalib/mxv.f new file mode 100644 index 00000000..266c1f85 --- /dev/null +++ b/math/slalib/mxv.f @@ -0,0 +1,69 @@ + SUBROUTINE slMXV (RM, VA, VB) +*+ +* - - - - +* M X V +* - - - - +* +* Performs the 3-D forward unitary transformation: +* +* vector VB = matrix RM * vector VA +* +* (single precision) +* +* Given: +* RM real(3,3) matrix +* VA real(3) vector +* +* Returned: +* VB real(3) result vector +* +* To comply with the ANSI Fortran 77 standard, VA and VB must be +* different arrays. However, the routine is coded so as to work +* properly on many platforms even if this rule is violated. +* +* Last revision: 26 December 2004 +* +* Copyright P.T.Wallace. All rights reserved. +* +* 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., 51 Franklin Street, Fifth Floor, +* Boston, MA 02110-1301 USA +* +* Copyright (C) 1995 Association of Universities for Research in Astronomy Inc. +*- + + IMPLICIT NONE + + REAL RM(3,3),VA(3),VB(3) + + INTEGER I,J + REAL W,VW(3) + + +* Matrix RM * vector VA -> vector VW + DO J=1,3 + W=0.0 + DO I=1,3 + W=W+RM(J,I)*VA(I) + END DO + VW(J)=W + END DO + +* Vector VW -> vector VB + DO J=1,3 + VB(J)=VW(J) + END DO + + END -- cgit