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+ SUBROUTINE sla_MXV (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
+*
+* P.T.Wallace Starlink March 1986
+*
+* Copyright (C) 1995 Rutherford Appleton Laboratory
+*-
+
+ 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