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+/*
+*+
+* Name:
+* palRvlg
+
+* Purpose:
+* Velocity component in a given direction due to Galactic rotation
+* and motion of the local group.
+
+* Language:
+* Starlink ANSI C
+
+* Type of Module:
+* Library routine
+
+* Invocation:
+* double palRvlg( double r2000, double d2000 )
+
+* Arguments:
+* r2000 = double (Given)
+* J2000.0 mean RA (radians)
+* d2000 = double (Given)
+* J2000.0 mean Dec (radians)
+
+* Returned Value:
+* Component of SOLAR motion in direction R2000,D2000 (km/s).
+
+* Description:
+* This function returns the 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. The result is +ve when the Sun
+* is receding from the given point on the sky.
+*
+* Reference:
+* - IAU Trans 1976, 168, p201.
+
+* Authors:
+* PTW: Pat Wallace (STFC)
+* DSB: David Berry (JAC, Hawaii)
+* {enter_new_authors_here}
+
+* History:
+* 2012-02-16 (DSB):
+* Initial version.
+* Adapted with permission from the Fortran SLALIB library.
+* {enter_further_changes_here}
+
+* Copyright:
+* Copyright (C) 1995 Rutherford Appleton Laboratory
+* Copyright (C) 2012 Science and Technology Facilities Council.
+* All Rights Reserved.
+
+* Licence:
+* This program is free software: you can redistribute it and/or
+* modify it under the terms of the GNU Lesser General Public
+* License as published by the Free Software Foundation, either
+* version 3 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 Lesser General Public License for more details.
+*
+* You should have received a copy of the GNU Lesser General
+* License along with this program. If not, see
+* <http://www.gnu.org/licenses/>.
+
+* Bugs:
+* {note_any_bugs_here}
+*-
+*/
+
+#include "pal.h"
+#include "pal1sofa.h"
+
+double palRvlg( double r2000, double d2000 ){
+
+/* Local Variables: */
+ double vb[ 3 ];
+
+/*
+*
+* 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)
+*/
+
+ double va[ 3 ] = { -148.23284, +133.44888, -224.09467 };
+
+/* Convert given J2000 RA,Dec to x,y,z. */
+ eraS2c( r2000, d2000, vb );
+
+/* Compute dot product with Solar motion vector. */
+ return eraPdp( va, vb );
+}