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SUBROUTINE sla_MXM (A, B, C)
*+
* - - - -
* M X M
* - - - -
*
* Product of two 3x3 matrices:
* matrix C = matrix A x matrix B
*
* (single precision)
*
* Given:
* A real(3,3) matrix
* B real(3,3) matrix
*
* Returned:
* C real(3,3) matrix result
*
* To comply with the ANSI Fortran 77 standard, A, B and C 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
REAL A(3,3),B(3,3),C(3,3)
INTEGER I,J,K
REAL W,WM(3,3)
* Multiply into scratch matrix
DO I=1,3
DO J=1,3
W=0.0
DO K=1,3
W=W+A(I,K)*B(K,J)
END DO
WM(I,J)=W
END DO
END DO
* Return the result
DO J=1,3
DO I=1,3
C(I,J)=WM(I,J)
END DO
END DO
END