#include <math.h>
#include <lal/Date.h>
#include <lal/LALRCSID.h>
Include dependency graph for XLALSiderealTime.c:
Go to the source code of this file.
Functions | |
| NRCSID (XLALSIDEREALTIMEC,"$Id: XLALSiderealTime.c,v 1.11 2008/04/30 18:53:06 kipp Exp $") | |
| REAL8 | XLALGreenwichSiderealTime (const LIGOTimeGPS *gpstime, REAL8 equation_of_equinoxes) |
| Returns the Greenwich mean or aparent sideral time in radians. | |
| REAL8 | XLALGreenwichMeanSiderealTime (const LIGOTimeGPS *gpstime) |
| Returns the Greenwich Mean Sidereal Time in RADIANS for a specified GPS time. | |
| LIGOTimeGPS * | XLALGreenwichMeanSiderealTimeToGPS (REAL8 gmst, LIGOTimeGPS *gps) |
| Returns the GPS time for the given Greenwich mean sidereal time (in radians). | |
| LIGOTimeGPS * | XLALGreenwichSiderealTimeToGPS (REAL8 gmst, REAL8 equation_of_equinoxes, LIGOTimeGPS *gps) |
| Returns the GPS time for the given Greenwich sidereal time (in radians). | |
Definition in file XLALSiderealTime.c.
| NRCSID | ( | XLALSIDEREALTIMEC | , | |
| "$Id: XLALSiderealTime. | c, | |||
| v 1.11 2008/04/30 18:53:06 kipp Exp $" | ||||
| ) |
| REAL8 XLALGreenwichSiderealTime | ( | const LIGOTimeGPS * | gpstime, | |
| REAL8 | equation_of_equinoxes | |||
| ) |
Returns the Greenwich mean or aparent sideral time in radians.
Aparent sidereal time is computed by providing the equation of equinoxes in units of seconds. For mean sidereal time, set this parameter to 0.
This function returns the sidereal time in radians measured from the Julian epoch (current J2000). The result is NOT modulo 2 pi.
Inspired by the function sidereal_time() in the NOVAS-C library, version 2.0.1, which is dated December 10th, 1999, and carries the following references:
Aoki, et al. (1982) Astronomy and Astrophysics 105, 359-361. Kaplan, G. H. "NOVAS: Naval Observatory Vector Astrometry Subroutines"; USNO internal document dated 20 Oct 1988; revised 15 Mar 1990.
See http://aa.usno.navy.mil/software/novas for more information.
Note: rather than maintaining this code separately, it would be a good idea for LAL to simply link to the NOVAS-C library directly. Something to do when we have some spare time.
Definition at line 62 of file XLALSiderealTime.c.
| REAL8 XLALGreenwichMeanSiderealTime | ( | const LIGOTimeGPS * | gpstime | ) |
Returns the Greenwich Mean Sidereal Time in RADIANS for a specified GPS time.
Definition at line 137 of file XLALSiderealTime.c.
| LIGOTimeGPS* XLALGreenwichMeanSiderealTimeToGPS | ( | REAL8 | gmst, | |
| LIGOTimeGPS * | gps | |||
| ) |
Returns the GPS time for the given Greenwich mean sidereal time (in radians).
The input is sidereal time in radians since the Julian epoch (currently J2000 for LAL), and the output is the corresponding GPS time. The algorithm uses a naive iterative root-finder, so it's slow.
Definition at line 153 of file XLALSiderealTime.c.
| LIGOTimeGPS* XLALGreenwichSiderealTimeToGPS | ( | REAL8 | gmst, | |
| REAL8 | equation_of_equinoxes, | |||
| LIGOTimeGPS * | gps | |||
| ) |
Returns the GPS time for the given Greenwich sidereal time (in radians).
Definition at line 182 of file XLALSiderealTime.c.
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