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authorJoseph Hunkeler <jhunkeler@gmail.com>2015-03-04 21:21:30 -0500
committerJoseph Hunkeler <jhunkeler@gmail.com>2015-03-04 21:21:30 -0500
commitd54fe7c1f704a63824c5bfa0ece65245572e9b27 (patch)
treeafc52015ffc2c74e0266653eecef1c8ef8ba5d91 /src/slalib/map.f
downloadcalfuse-d54fe7c1f704a63824c5bfa0ece65245572e9b27.tar.gz
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+ SUBROUTINE sla_MAP (RM, DM, PR, PD, PX, RV, EQ, DATE, RA, DA)
+*+
+* - - - -
+* M A P
+* - - - -
+*
+* Transform star RA,Dec from mean place to geocentric apparent
+*
+* The reference frames and timescales used are post IAU 1976.
+*
+* References:
+* 1984 Astronomical Almanac, pp B39-B41.
+* (also Lederle & Schwan, Astron. Astrophys. 134,
+* 1-6, 1984)
+*
+* Given:
+* RM,DM dp mean RA,Dec (rad)
+* PR,PD dp proper motions: RA,Dec changes per Julian year
+* PX dp parallax (arcsec)
+* RV dp radial velocity (km/sec, +ve if receding)
+* EQ dp epoch and equinox of star data (Julian)
+* DATE dp TDB for apparent place (JD-2400000.5)
+*
+* Returned:
+* RA,DA dp apparent RA,Dec (rad)
+*
+* Called:
+* sla_MAPPA star-independent parameters
+* sla_MAPQK quick mean to apparent
+*
+* Notes:
+*
+* 1) EQ is the Julian epoch specifying both the reference
+* frame and the epoch of the position - usually 2000.
+* For positions where the epoch and equinox are
+* different, use the routine sla_PM to apply proper
+* motion corrections before using this routine.
+*
+* 2) The distinction between the required TDB and TT is
+* always negligible. Moreover, for all but the most
+* critical applications UTC is adequate.
+*
+* 3) The proper motions in RA are dRA/dt rather than
+* cos(Dec)*dRA/dt.
+*
+* 4) This routine may be wasteful for some applications
+* because it recomputes the Earth position/velocity and
+* the precession/nutation matrix each time, and because
+* it allows for parallax and proper motion. Where
+* multiple transformations are to be carried out for one
+* epoch, a faster method is to call the sla_MAPPA routine
+* once and then either the sla_MAPQK routine (which includes
+* parallax and proper motion) or sla_MAPQKZ (which assumes
+* zero parallax and proper motion).
+*
+* P.T.Wallace Starlink 19 January 1993
+*
+* Copyright (C) 1995 Rutherford Appleton Laboratory
+*-
+
+ IMPLICIT NONE
+
+ DOUBLE PRECISION RM,DM,PR,PD,PX,RV,EQ,DATE,RA,DA
+
+ DOUBLE PRECISION AMPRMS(21)
+
+
+
+* Star-independent parameters
+ CALL sla_MAPPA(EQ,DATE,AMPRMS)
+
+* Mean to apparent
+ CALL sla_MAPQK(RM,DM,PR,PD,PX,RV,AMPRMS,RA,DA)
+
+ END