File Coverage

palsrc/palGaleq.c
Criterion Covered Total %
statement 0 8 0.0
branch n/a
condition n/a
subroutine n/a
pod n/a
total 0 8 0.0


line stmt bran cond sub pod time code
1             /*
2             *+
3             * Name:
4             * palGaleq
5              
6             * Purpose:
7             * Convert from galactic to J2000.0 equatorial coordinates
8              
9             * Language:
10             * Starlink ANSI C
11              
12             * Type of Module:
13             * Library routine
14              
15             * Invocation:
16             * void palGaleq ( double dl, double db, double *dr, double *dd );
17              
18             * Arguments:
19             * dl = double (Given)
20             * Galactic longitude (radians).
21             * db = double (Given)
22             * Galactic latitude (radians).
23             * dr = double * (Returned)
24             * J2000.0 RA (radians)
25             * dd = double * (Returned)
26             * J2000.0 Dec (radians)
27              
28             * Description:
29             * Transformation from IAU 1958 galactic coordinates to
30             * J2000.0 equatorial coordinates.
31              
32             * Authors:
33             * PTW: Pat Wallace (STFC)
34             * TIMJ: Tim Jenness (JAC, Hawaii)
35             * {enter_new_authors_here}
36              
37             * Notes:
38             * The equatorial coordinates are J2000.0. Use the routine
39             * palGe50 if conversion to B1950.0 'FK4' coordinates is
40             * required.
41              
42             * See Also:
43             * Blaauw et al, Mon.Not.R.Astron.Soc.,121,123 (1960)
44              
45             * History:
46             * 2012-02-12(TIMJ):
47             * Initial version with documentation taken from Fortran SLA
48             * Adapted with permission from the Fortran SLALIB library.
49             * {enter_further_changes_here}
50              
51             * Copyright:
52             * Copyright (C) 1998 Rutherford Appleton Laboratory
53             * Copyright (C) 2012 Science and Technology Facilities Council.
54             * All Rights Reserved.
55              
56             * Licence:
57             * This program is free software: you can redistribute it and/or
58             * modify it under the terms of the GNU Lesser General Public
59             * License as published by the Free Software Foundation, either
60             * version 3 of the License, or (at your option) any later
61             * version.
62             *
63             * This program is distributed in the hope that it will be useful,
64             * but WITHOUT ANY WARRANTY; without even the implied warranty of
65             * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
66             * GNU Lesser General Public License for more details.
67             *
68             * You should have received a copy of the GNU Lesser General
69             * License along with this program. If not, see
70             * .
71              
72             * Bugs:
73             * {note_any_bugs_here}
74             *-
75             */
76              
77             #include "pal.h"
78             #include "pal1sofa.h"
79              
80 0           void palGaleq ( double dl, double db, double *dr, double *dd ) {
81              
82             double v1[3];
83             double v2[3];
84              
85             /*
86             * L2,B2 system of galactic coordinates
87             *
88             * P = 192.25 RA of galactic north pole (mean B1950.0)
89             * Q = 62.6 inclination of galactic to mean B1950.0 equator
90             * R = 33 longitude of ascending node
91             *
92             * P,Q,R are degrees
93             *
94             * Equatorial to galactic rotation matrix (J2000.0), obtained by
95             * applying the standard FK4 to FK5 transformation, for zero proper
96             * motion in FK5, to the columns of the B1950 equatorial to
97             * galactic rotation matrix:
98             */
99 0           double rmat[3][3] = {
100             { -0.054875539726,-0.873437108010,-0.483834985808 },
101             { +0.494109453312,-0.444829589425,+0.746982251810 },
102             { -0.867666135858,-0.198076386122,+0.455983795705 }
103             };
104              
105             /* Spherical to Cartesian */
106 0           eraS2c( dl, db, v1 );
107              
108             /* Galactic to equatorial */
109 0           eraTrxp( rmat, v1, v2 );
110              
111             /* Cartesian to spherical */
112 0           eraC2s( v2, dr, dd );
113              
114             /* Express in conventional ranges */
115 0           *dr = eraAnp( *dr );
116 0           *dd = eraAnpm( *dd );
117              
118 0           }