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diff --git a/src/libcf/solar_ang.c b/src/libcf/solar_ang.c
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+/******************************************************************************
+ *              Johns Hopkins University
+ *              Center For Astrophysical Sciences
+ *              FUSE
+ ******************************************************************************
+ *
+ * Synopsis:    double solar_ang(double mjdate, double ra, double dec)
+ *
+ * Description: Computes the angle between the Sun and J2000.0 RA and DEC
+ *              for a given date.
+ *
+ * Arguments:   double mjdate         Modified Julian date of observation
+ *              double ra             (deg) J2000.0 right ascension
+ *              double dec            (deg) J2000.0 declination 
+ *
+ * Returns:     double                (deg) angle between Sun and RA,DEC
+ *                    
+ * Calls:       slaDcc2s              dcc2s.f
+ *              slaDsep               dsep.f
+ *              slaDranrm             dranrm.f
+ *              slaEvp                evp.f
+ *
+ * History:     03/10/98  E. Murphy   Begin work.
+ *              03/10/98  E. Murphy   Initial version working
+ *              05/31/00        peb   Implemented cfortran.h calls for slalib
+ *                                    functions.
+ *              12/18/03    bjg       Change calfusettag.h to calfuse.h
+ *		07/21/04  1.4   wvd   Comment out variable vect; unused.
+ *
+ * References:  This routine makes use of the Starlink set of astronomical
+ *              subroutines (SLALIB).  More information can be found at
+ *              http://star-www.rl.ac.uk.
+ *****************************************************************************/
+ 
+#include <stdio.h>
+#include <math.h>
+
+#ifdef CFORTRAN
+#include "cfortran.h"
+PROTOCCALLSFSUB3(SLA_DCC2S, sla_dcc2s, DOUBLEV, PDOUBLE, PDOUBLE)
+#define slaDcc2s(V, A, B) \
+     CCALLSFSUB3(SLA_DCC2S, sla_dcc2s, DOUBLEV, PDOUBLE, PDOUBLE, V, A, B)
+PROTOCCALLSFFUN1(DOUBLE, SLA_DRANRM, sla_dranrm, DOUBLE)
+#define slaDranrm(ANGLE) \
+     CCALLSFFUN1(SLA_DRANRM, sla_dranrm, DOUBLE, ANGLE)
+PROTOCCALLSFFUN4(DOUBLE, SLA_DSEP, sla_dsep, DOUBLE, DOUBLE, DOUBLE, DOUBLE)
+#define slaDsep(A1, B1, A2, B2) \
+     CCALLSFFUN4(SLA_DSEP, sla_dsep, DOUBLE, DOUBLE, DOUBLE, DOUBLE, \
+		 A1, B1, A2, B2)
+PROTOCCALLSFSUB6(SLA_EVP, sla_evp, DOUBLE, DOUBLE, DOUBLEV, DOUBLEV, DOUBLEV, \
+		 DOUBLEV)
+#define slaEvp(DATE, DEQX, DVB, DPB, DVH, DPH) \
+     CCALLSFSUB6(SLA_EVP, sla_evp, DOUBLE, DOUBLE, DOUBLEV, DOUBLEV, DOUBLEV, \
+		 DOUBLEV, DATE, DEQX, DVB, DPB, DVH, DPH)
+#else
+#include "slalib.h"
+#include "slamac.h"
+#endif
+
+#include "calfuse.h"
+ 
+double solar_ang(double mjdate, double ra, double dec)
+{
+    /* Define variables. */
+    int i;
+    /* double dvb[3], dpb[3], dvh[3], dph[3], vect[3], ra_sun, dec_sun; */
+    double dvb[3], dpb[3], dvh[3], dph[3], ra_sun, dec_sun;
+    /*
+     *  Evp returns four 3-vectors containing the barycentric velocity and
+     *  position (dvb,dpv) and the heliocentric velocity and position 
+     *  (dvh,dph) of the Earth on the date mjdate.  It requires a modified 
+     *  Julian date as input.  Output has units of AU for positions and 
+     *  AU/s for velocities.
+     */
+    slaEvp(mjdate, 2000.0, dvb, dpb, dvh, dph);
+
+    /*  Convert the 3-vector position of the Sun into a J2000.0 RA and DEC */
+
+    for (i=0; i<3; i++) dph[i]*=-1.0;
+
+#ifdef CFORTRAN
+    slaDcc2s(dph, ra_sun, dec_sun);
+#else
+    slaDcc2s(dph, &ra_sun, &dec_sun);
+#endif
+
+    /*  Compute the angular separation of RA,DEC and RA_SUN and DEC_SUN */
+
+    return slaDsep(ra*RADIAN, dec*RADIAN, slaDranrm(ra_sun), dec_sun)/RADIAN;
+}