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author | Joe Hunkeler <jhunkeler@gmail.com> | 2015-08-11 16:51:37 -0400 |
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committer | Joe Hunkeler <jhunkeler@gmail.com> | 2015-08-11 16:51:37 -0400 |
commit | 40e5a5811c6ffce9b0974e93cdd927cbcf60c157 (patch) | |
tree | 4464880c571602d54f6ae114729bf62a89518057 /math/slalib/fk54z.f | |
download | iraf-osx-40e5a5811c6ffce9b0974e93cdd927cbcf60c157.tar.gz |
Repatch (from linux) of OSX IRAF
Diffstat (limited to 'math/slalib/fk54z.f')
-rw-r--r-- | math/slalib/fk54z.f | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/math/slalib/fk54z.f b/math/slalib/fk54z.f new file mode 100644 index 00000000..69a93461 --- /dev/null +++ b/math/slalib/fk54z.f @@ -0,0 +1,87 @@ + SUBROUTINE slF54Z (R2000,D2000,BEPOCH, + : R1950,D1950,DR1950,DD1950) +*+ +* - - - - - - +* F 5 4 Z +* - - - - - - +* +* Convert a J2000.0 FK5 star position to B1950.0 FK4 assuming +* zero proper motion and parallax (double precision) +* +* This routine converts star positions from the new, IAU 1976, +* FK5, Fricke system to the old, Bessel-Newcomb, FK4 system. +* +* Given: +* R2000,D2000 dp J2000.0 FK5 RA,Dec (rad) +* BEPOCH dp Besselian epoch (e.g. 1950D0) +* +* Returned: +* R1950,D1950 dp B1950.0 FK4 RA,Dec (rad) at epoch BEPOCH +* DR1950,DD1950 dp B1950.0 FK4 proper motions (rad/trop.yr) +* +* Notes: +* +* 1) The proper motion in RA is dRA/dt rather than cos(Dec)*dRA/dt. +* +* 2) Conversion from Julian epoch 2000.0 to Besselian epoch 1950.0 +* only is provided for. Conversions involving other epochs will +* require use of the appropriate precession routines before and +* after this routine is called. +* +* 3) Unlike in the slFK54 routine, the FK5 proper motions, the +* parallax and the radial velocity are presumed zero. +* +* 4) It is the intention that FK5 should be a close approximation +* to an inertial frame, so that distant objects have zero proper +* motion; such objects have (in general) non-zero proper motion +* in FK4, and this routine returns those fictitious proper +* motions. +* +* 5) The position returned by this routine is in the B1950 +* reference frame but at Besselian epoch BEPOCH. For +* comparison with catalogues the BEPOCH argument will +* frequently be 1950D0. +* +* Called: slFK54, slPM +* +* P.T.Wallace Starlink 10 April 1990 +* +* Copyright (C) 1995 Rutherford Appleton Laboratory +* +* License: +* This program is free software; you can redistribute it and/or modify +* it under the terms of the GNU General Public License as published by +* the Free Software Foundation; either version 2 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 General Public License for more details. +* +* You should have received a copy of the GNU General Public License +* along with this program (see SLA_CONDITIONS); if not, write to the +* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, +* Boston, MA 02110-1301 USA +* +* Copyright (C) 1995 Association of Universities for Research in Astronomy Inc. +*- + + IMPLICIT NONE + + DOUBLE PRECISION R2000,D2000,BEPOCH, + : R1950,D1950,DR1950,DD1950 + + DOUBLE PRECISION R,D,PX,RV + + + +* FK5 equinox J2000 (any epoch) to FK4 equinox B1950 epoch B1950 + CALL slFK54(R2000,D2000,0D0,0D0,0D0,0D0, + : R,D,DR1950,DD1950,PX,RV) + +* Fictitious proper motion to epoch BEPOCH + CALL slPM(R,D,DR1950,DD1950,0D0,0D0,1950D0,BEPOCH, + : R1950,D1950) + + END |