1 files changed, 99 insertions, 0 deletions
diff --git a/ast/pal/palCaldj.c b/ast/pal/palCaldj.c
new file mode 100644
index 0000000..03c6b97
--- /dev/null
+++ b/ast/pal/palCaldj.c
@@ -0,0 +1,99 @@
+/*
+*+
+*  Name:
+*     palCaldj
+
+*  Purpose:
+*     Gregorian Calendar to Modified Julian Date
+
+*  Language:
+*     Starlink ANSI C
+
+*  Type of Module:
+*     Library routine
+
+*  Invocation:
+*     void palCaldj ( int iy, int im, int id, double *djm, int *j );
+
+*  Arguments:
+*     iy = int (Given)
+*        Year in the Gregorian calendar
+*     im = int (Given)
+*        Month in the Gergorian calendar
+*     id = int (Given)
+*        Day in the Gregorian calendar
+*     djm = double * (Returned)
+*        Modified Julian Date (JD-2400000.5) for 0 hrs
+*     j = status (Returned)
+*       0 = OK. See eraCal2jd for other values.
+
+*  Description:
+*     Modified Julian Date to Gregorian Calendar with special
+*     behaviour for 2-digit years relating to 1950 to 2049.
+
+*  Authors:
+*     PTW: Pat Wallace (STFC)
+*     TIMJ: Tim Jenness (JAC, Hawaii)
+*     {enter_new_authors_here}
+
+*  History:
+*     2012-02-11 (TIMJ):
+*        Initial version with documentation taken from Fortran SLA
+*        Adapted with permission from the Fortran SLALIB library.
+*     {enter_further_changes_here}
+
+*  Notes:
+*     - Uses eraCal2jd
+*     - Unlike eraCal2jd this routine treats the years 0-100 as
+*       referring to the end of the 20th Century and beginning of
+*       the 21st Century. If this behaviour is not acceptable
+*       use the SOFA/ERFA routine directly or palCldj.
+*       Acceptable years are 00-49, interpreted as 2000-2049,
+*                            50-99,     "       "  1950-1999,
+*                            all others, interpreted literally.
+*     - Unlike SLA this routine will work with negative years.
+
+
+*  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 "palmac.h"
+#include "pal1sofa.h"
+
+void palCaldj ( int iy, int im, int id, double *djm, int *j ) {
+  int adj = 0;   /* Year adjustment */
+  double djm0;
+
+  if (iy >= 0 && iy <= 49) {
+    adj = 2000;
+  } else if (iy >= 50 && iy <= 99) {
+    adj = 1900;
+  }
+  iy += adj;
+
+  *j = eraCal2jd( iy, im, id, &djm0, djm );
+}