dmxv.f

      SUBROUTINE sla_DMXV (DM, VA, VB)
*+
*     - - - - -
*      D M X V
*     - - - - -
*
*  Performs the 3-D forward unitary transformation:
*
*     vector VB = matrix DM * vector VA
*
*  (double precision)
*
*  Given:
*     DM       dp(3,3)    matrix
*     VA       dp(3)      vector
*
*  Returned:
*     VB       dp(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., 59 Temple Place, Suite 330, 
*    Boston, MA  02111-1307  USA
*
*-

      IMPLICIT NONE

      DOUBLE PRECISION DM(3,3),VA(3),VB(3)

      INTEGER I,J
      DOUBLE PRECISION W,VW(3)


*  Matrix DM * vector VA -> vector VW
      DO J=1,3
         W=0D0
         DO I=1,3
            W=W+DM(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