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+      REAL FUNCTION sla_RVLG (R2000, D2000)
+*+
+*     - - - - -
+*      R V L G
+*     - - - - -
+*
+*  Velocity component in a given direction due to the combination
+*  of the rotation of the Galaxy and the motion of the Galaxy
+*  relative to the mean motion of the local group (single precision)
+*
+*  Given:
+*     R2000,D2000   real    J2000.0 mean RA,Dec (radians)
+*
+*  Result:
+*     Component of SOLAR motion in direction R2000,D2000 (km/s)
+*
+*  Sign convention:
+*     The result is +ve when the Sun is receding from the
+*     given point on the sky.
+*
+*  Reference:
+*     IAU Trans 1976, 168, p201.
+*
+*  Called:
+*     sla_CS2C, sla_VDV
+*
+*  P.T.Wallace   Starlink   June 1985
+*
+*  Copyright (C) 1995 Rutherford Appleton Laboratory
+*-
+
+      IMPLICIT NONE
+
+      REAL R2000,D2000
+
+      REAL VA(3), VB(3)
+
+      REAL sla_VDV
+
+*
+*  Solar velocity due to Galactic rotation and translation
+*
+*  Speed = 300 km/s
+*
+*  Apex  = L2,B2  90deg, 0deg
+*        = RA,Dec  21 12 01.1  +48 19 47  J2000.0
+*
+*  This is expressed in the form of a J2000.0 x,y,z vector:
+*
+*      VA(1) = X = -SPEED*COS(RA)*COS(DEC)
+*      VA(2) = Y = -SPEED*SIN(RA)*COS(DEC)
+*      VA(3) = Z = -SPEED*SIN(DEC)
+
+      DATA VA / -148.23284, +133.44888, -224.09467 /
+
+
+
+*  Convert given J2000 RA,Dec to x,y,z
+      CALL sla_CS2C(R2000,D2000,VB)
+
+*  Compute dot product with Solar motion vector
+      sla_RVLG=sla_VDV(VA,VB)
+
+      END