Changeset 2551 in Sophya for trunk/SophyaExt/XephemAstroLib/utc_gst.c

Timestamp:

Jun 15, 2004, 6:54:12 PM (21 years ago)

Author:

cmv

Message:

nouvelle version de xephem/libastro (3.6) cmv 15/6/04

File:

• trunk/SophyaExt/XephemAstroLib/utc_gst.c (modified) (6 diffs)

trunk/SophyaExt/XephemAstroLib/utc_gst.c

@@ -1 @@
-#include "P_.h"
 #include "astro.h"
 
-static double gmst0 P_((double mjd));
+static double gmst0 (double mj);
 
-/* given a modified julian date, mjd, and a universally coordinated time, utc,
+/* given a modified julian date, mj, and a universally coordinated time, utc,
  * return greenwich mean siderial time, *gst.
- * N.B. mjd must be at the beginning of the day.
+ * N.B. mj must be at the beginning of the day.
  */
 void
-utc_gst (mjd, utc, gst)
-double mjd;
-double utc;
-double *gst;
+utc_gst (double mj, double utc, double *gst)
 {
-        static double lastmjd = -18981;
+        static double lastmj = -18981;
         static double t0;
 
-        if (mjd != lastmjd) {
-            t0 = gmst0(mjd);
-            lastmjd = mjd;
+        if (mj != lastmj) {
+            t0 = gmst0(mj);
+            lastmj = mj;
         }
         *gst = (1.0/SIDRATE)*utc + t0;
@@ -25 +21 @@
 }
 
-/* given a modified julian date, mjd, and a greenwich mean siderial time, gst,
+/* given a modified julian date, mj, and a greenwich mean siderial time, gst,
  * return universally coordinated time, *utc.
- * N.B. mjd must be at the beginning of the day.
+ * N.B. mj must be at the beginning of the day.
  */
 void
-gst_utc (mjd, gst, utc)
-double mjd;
-double gst;
-double *utc;
+gst_utc (double mj, double gst, double *utc)
 {
-        static double lastmjd = -10000;
+        static double lastmj = -10000;
         static double t0;
 
-        if (mjd != lastmjd) {
-            t0 = gmst0 (mjd);
-            lastmjd = mjd;
+        if (mj != lastmj) {
+            t0 = gmst0 (mj);
+            lastmj = mj;
         }
         *utc = gst - t0;
@@ -50 +43 @@
  */
 static double
-gmst0 (mjd)
-double mjd;     /* date at 0h UT in julian days since MJD0 */
+gmst0 (
+double mj)      /* date at 0h UT in julian days since MJD0 */
 {
         double T, x;
 
-        T = ((int)(mjd - 0.5) + 0.5 - J2000)/36525.0;
+        T = ((int)(mj - 0.5) + 0.5 - J2000)/36525.0;
         x = 24110.54841 +
                 (8640184.812866 + (0.093104 - 6.2e-6 * T) * T) * T;
@@ -67 +60 @@
 /* original routine by elwood; has a secular drift of 0.08s/cty */
 static double
-tnaught (mjd)
-double mjd;     /* julian days since 1900 jan 0.5 */
+tnaught (mj)
+double mj;      /* julian days since 1900 jan 0.5 */
 {
-        double dmjd;
+        double dmj;
         int m, y;
         double d;
         double t, t0;
 
-        mjd_cal (mjd, &m, &d, &y);
-        cal_mjd (1, 0., y, &dmjd);
-        t = dmjd/36525;
-        t0 = 6.57098e-2 * (mjd - dmjd) - 
+        mjd_cal (mj, &m, &d, &y);
+        cal_mjd (1, 0., y, &dmj);
+        t = dmj/36525;
+        t0 = 6.57098e-2 * (mj - dmj) - 
              (24 - (6.6460656 + (5.1262e-2 + (t * 2.581e-5))*t) -
                    (2400 * (t - (((double)y - 1900)/100))));
@@ -90 +83 @@
   char *argv[];
 {
-        double mjd, gst;
-        while (scanf("%lf", &mjd) == 1) {
-                mjd -= MJD0;
-                gst = tnaught(mjd);
-                printf("%17.9f %10.7f %10.7f\n", mjd + MJD0, gst, gmst0(mjd));
+        double mj, gst;
+        while (scanf("%lf", &mj) == 1) {
+                mj -= MJD0;
+                gst = tnaught(mj);
+                printf("%17.9f %10.7f %10.7f\n", mj + MJD0, gst, gmst0(mj));
         }
 }
@@ -100 +93 @@
 
 /* For RCS Only -- Do Not Edit */
-static char *rcsid[2] = {(char *)rcsid, "@(#) $RCSfile: utc_gst.c,v $ $Date: 2001-10-22 12:08:28 $ $Revision: 1.2 $ $Name: not supported by cvs2svn $"};
+static char *rcsid[2] = {(char *)rcsid, "@(#) $RCSfile: utc_gst.c,v $ $Date: 2004-06-15 16:52:41 $ $Revision: 1.3 $ $Name: not supported by cvs2svn $"};