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C $Id: mxvect.f,v 1.3 1993/07/16 22:56:19 gdsjaar Exp $
C $Log: mxvect.f,v $
C Revision 1.3  1993/07/16 22:56:19  gdsjaar
C Unrolled loops for faster execution
C
c Revision 1.2  1993/07/16  19:30:48  gdsjaar
c Restructured to optimize faster
c
c Revision 1.1  1993/07/16  16:47:36  gdsjaar
c Changed plt to library rather than single source file.
c
C=======================================================================
      SUBROUTINE MXVECT(N,VEC,MAT,RES)
      REAL VEC(*),MAT(N,*),RES(*)

      IF (N .EQ. 4) THEN
        RES(1) = MAT(1,1)*VEC(1) + MAT(2,1)*VEC(2) + MAT(3,1)*VEC(3) +
     *    MAT(4,1)*VEC(4)

        RES(2) = MAT(1,2)*VEC(1) + MAT(2,2)*VEC(2) + MAT(3,2)*VEC(3) +
     *    MAT(4,2)*VEC(4)

        RES(3) = MAT(1,3)*VEC(1) + MAT(2,3)*VEC(2) + MAT(3,3)*VEC(3) +
     *    MAT(4,3)*VEC(4)

        RES(4) = MAT(1,4)*VEC(1) + MAT(2,4)*VEC(2) + MAT(3,4)*VEC(3) +
     *    MAT(4,4)*VEC(4)

      ELSE
        DO 2980 J = 1,N
          RES(J) = 0.0
 2980   CONTINUE
        DO 3010 I = 1,N
          DO 2990 J = 1,N
            RES(J) = RES(J) + MAT(I,J)*VEC(I)
 2990     CONTINUE
 3010   CONTINUE
      END IF
      RETURN

      END
