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diff --git a/ast/pal/palFk45z.c b/ast/pal/palFk45z.c
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+/*
+*+
+*  Name:
+*     palFk45z
+
+*  Purpose:
+*     Convert B1950.0 FK4 star data to J2000.0 FK5 assuming zero
+*     proper motion in the FK5 frame
+
+*  Language:
+*     Starlink ANSI C
+
+*  Type of Module:
+*     Library routine
+
+*  Invocation:
+*     palFk45z( double r1950, double d1950, double bepoch, double *r2000,
+*               double *d2000 )
+
+*  Arguments:
+*     r1950 = double (Given)
+*        B1950.0 FK4 RA at epoch (radians).
+*     d1950 = double (Given)
+*        B1950.0 FK4 Dec at epoch (radians).
+*     bepoch = double (Given)
+*        Besselian epoch (e.g. 1979.3)
+*     r2000 = double (Returned)
+*        J2000.0 FK5 RA (Radians).
+*     d2000 = double (Returned)
+*        J2000.0 FK5 Dec(Radians).
+
+*  Description:
+*     Convert B1950.0 FK4 star data to J2000.0 FK5 assuming zero
+*     proper motion in the FK5 frame (double precision)
+*
+*     This function converts stars from the Bessel-Newcomb, FK4
+*     system to the IAU 1976, FK5, Fricke system, in such a
+*     way that the FK5 proper motion is zero.  Because such a star
+*     has, in general, a non-zero proper motion in the FK4 system,
+*     the routine requires the epoch at which the position in the
+*     FK4 system was determined.
+*
+*     The method is from Appendix 2 of Ref 1, but using the constants
+*     of Ref 4.
+
+*  Notes:
+*     - The epoch BEPOCH is strictly speaking Besselian, but if a
+*     Julian epoch is supplied the result will be affected only to
+*     a negligible extent.
+*
+*     - Conversion from Besselian epoch 1950.0 to Julian epoch 2000.0
+*     only is provided for.  Conversions involving other epochs will
+*     require use of the appropriate precession, proper motion, and
+*     E-terms routines before and/or after palFk45z is called.
+*
+*     - In the FK4 catalogue the proper motions of stars within 10
+*     degrees of the poles do not embody the differential E-term effect
+*     and should, strictly speaking, be handled in a different manner
+*     from stars outside these regions. However, given the general lack
+*     of homogeneity of the star data available for routine astrometry,
+*     the difficulties of handling positions that may have been
+*     determined from astrometric fields spanning the polar and non-polar
+*     regions, the likelihood that the differential E-terms effect was not
+*     taken into account when allowing for proper motion in past
+*     astrometry, and the undesirability of a discontinuity in the
+*     algorithm, the decision has been made in this routine to include the
+*     effect of differential E-terms on the proper motions for all stars,
+*     whether polar or not.  At epoch 2000, and measuring on the sky rather
+*     than in terms of dRA, the errors resulting from this simplification
+*     are less than 1 milliarcsecond in position and 1 milliarcsecond per
+*     century in proper motion.
+*
+*  References:
+*     - Aoki,S., et al, 1983.  Astron.Astrophys., 128, 263.
+*     - Smith, C.A. et al, 1989.  "The transformation of astrometric
+*       catalog systems to the equinox J2000.0".  Astron.J. 97, 265.
+*     - Yallop, B.D. et al, 1989.  "Transformation of mean star places
+*       from FK4 B1950.0 to FK5 J2000.0 using matrices in 6-space".
+*       Astron.J. 97, 274.
+*     - Seidelmann, P.K. (ed), 1992.  "Explanatory Supplement to
+*       the Astronomical Almanac", ISBN 0-935702-68-7.
+
+*  Authors:
+*     PTW: Pat Wallace (STFC)
+*     DSB: David Berry (JAC, Hawaii)
+*     {enter_new_authors_here}
+
+*  History:
+*     2012-02-10 (DSB):
+*        Initial version with documentation taken from Fortran SLA
+*        Adapted with permission from the Fortran SLALIB library.
+*     {enter_further_changes_here}
+
+*  Copyright:
+*     Copyright (C) 1998 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 "palmac.h"
+#include "pal1sofa.h"
+
+void palFk45z( double r1950, double d1950, double bepoch, double *r2000,
+               double *d2000 ){
+
+/* Local Variables: */
+   double w;
+   int i;
+   int j;
+   double r0[3], a1[3], v1[3], v2[6]; /* Position and position+velocity vectors */
+
+
+/* CANONICAL CONSTANTS  (see references) */
+
+/* Vector A. */
+   double a[3] = { -1.62557E-6, -0.31919E-6, -0.13843E-6 };
+
+/* Vectors Adot. */
+   double ad[3] = { 1.245E-3, -1.580E-3, -0.659E-3 };
+
+/* Matrix M (only half of which is needed here). */
+   double em[6][3] = { {0.9999256782, -0.0111820611, -0.0048579477},
+                       {0.0111820610, 0.9999374784, -0.0000271765},
+                       {0.0048579479, -0.0000271474, 0.9999881997},
+                       {-0.000551, -0.238565, 0.435739},
+                       {0.238514, -0.002667, -0.008541},
+                       {-0.435623, 0.012254, 0.002117} };
+
+
+/* Spherical to Cartesian. */
+   eraS2c( r1950, d1950, r0 );
+
+/* Adjust vector A to give zero proper motion in FK5. */
+   w = ( bepoch - 1950.0 )/PAL__PMF;
+   for( i = 0; i < 3; i++ ) {
+      a1[ i ] = a[ i ] + w*ad[ i ];
+   }
+
+/* Remove e-terms. */
+   w = r0[ 0 ]*a1[ 0 ] + r0[ 1 ]*a1[ 1 ] + r0[ 2 ]*a1[ 2 ];
+   for( i = 0; i < 3; i++ ) {
+      v1[ i ] = r0[ i ] - a1[ i ] + w*r0[ i ];
+   }
+
+/* Convert position vector to Fricke system. */
+   for( i = 0; i < 6; i++ ) {
+      w = 0.0;
+      for( j = 0; j < 3; j++ ) {
+         w += em[ i ][ j ]*v1[ j ];
+      }
+      v2[ i ] = w;
+   }
+
+/* Allow for fictitious proper motion in FK4. */
+   w = ( palEpj( palEpb2d( bepoch ) ) - 2000.0 )/PAL__PMF;
+   for( i = 0; i < 3; i++ ) {
+      v2[ i ] += w*v2[ i + 3 ];
+   }
+
+/* Revert to spherical coordinates. */
+   eraC2s( v2, &w, d2000 );
+   *r2000 = eraAnp( w );
+}
+
+