File Coverage

erfasrc/src/c2teqx.c

Criterion	Covered	Total	%
statement	0	5	0.0
branch			n/a
condition			n/a
subroutine			n/a
pod			n/a
total	0	5	0.0

line	stmt	code
1		#include "erfa.h"
2
3	0	void eraC2teqx(double rbpn[3][3], double gst, double rpom[3][3],
4		double rc2t[3][3])
5		/*
6		** - - - - - - - - - -
7		** e r a C 2 t e q x
8		** - - - - - - - - - -
9		**
10		** Assemble the celestial to terrestrial matrix from equinox-based
11		** components (the celestial-to-true matrix, the Greenwich Apparent
12		** Sidereal Time and the polar motion matrix).
13		**
14		** Given:
15		** rbpn double[3][3] celestial-to-true matrix
16		** gst double Greenwich (apparent) Sidereal Time (radians)
17		** rpom double[3][3] polar-motion matrix
18		**
19		** Returned:
20		** rc2t double[3][3] celestial-to-terrestrial matrix (Note 2)
21		**
22		** Notes:
23		**
24		** 1) This function constructs the rotation matrix that transforms
25		** vectors in the celestial system into vectors in the terrestrial
26		** system. It does so starting from precomputed components, namely
27		** the matrix which rotates from celestial coordinates to the
28		** true equator and equinox of date, the Greenwich Apparent Sidereal
29		** Time and the polar motion matrix. One use of the present function
30		** is when generating a series of celestial-to-terrestrial matrices
31		** where only the Sidereal Time changes, avoiding the considerable
32		** overhead of recomputing the precession-nutation more often than
33		** necessary to achieve given accuracy objectives.
34		**
35		** 2) The relationship between the arguments is as follows:
36		**
37		** [TRS] = rpom * R_3(gst) * rbpn * [CRS]
38		**
39		** = rc2t * [CRS]
40		**
41		** where [CRS] is a vector in the Geocentric Celestial Reference
42		** System and [TRS] is a vector in the International Terrestrial
43		** Reference System (see IERS Conventions 2003).
44		**
45		** Called:
46		** eraCr copy r-matrix
47		** eraRz rotate around Z-axis
48		** eraRxr product of two r-matrices
49		**
50		** Reference:
51		**
52		** McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003),
53		** IERS Technical Note No. 32, BKG (2004)
54		**
55		** Copyright (C) 2013-2020, NumFOCUS Foundation.
56		** Derived, with permission, from the SOFA library. See notes at end of file.
57		*/
58		{
59		double r[3][3];
60
61
62		/* Construct the matrix. */
63	0	eraCr(rbpn, r);
64	0	eraRz(gst, r);
65	0	eraRxr(rpom, r, rc2t);
66
67	0	return;
68
69		}
70		/*----------------------------------------------------------------------
71		**
72		**
73		** Copyright (C) 2013-2020, NumFOCUS Foundation.
74		** All rights reserved.
75		**
76		** This library is derived, with permission, from the International
77		** Astronomical Union's "Standards of Fundamental Astronomy" library,
78		** available from http://www.iausofa.org.
79		**
80		** The ERFA version is intended to retain identical functionality to
81		** the SOFA library, but made distinct through different function and
82		** file names, as set out in the SOFA license conditions. The SOFA
83		** original has a role as a reference standard for the IAU and IERS,
84		** and consequently redistribution is permitted only in its unaltered
85		** state. The ERFA version is not subject to this restriction and
86		** therefore can be included in distributions which do not support the
87		** concept of "read only" software.
88		**
89		** Although the intent is to replicate the SOFA API (other than
90		** replacement of prefix names) and results (with the exception of
91		** bugs; any that are discovered will be fixed), SOFA is not
92		** responsible for any errors found in this version of the library.
93		**
94		** If you wish to acknowledge the SOFA heritage, please acknowledge
95		** that you are using a library derived from SOFA, rather than SOFA
96		** itself.
97		**
98		**
99		** TERMS AND CONDITIONS
100		**
101		** Redistribution and use in source and binary forms, with or without
102		** modification, are permitted provided that the following conditions
103		** are met:
104		**
105		** 1 Redistributions of source code must retain the above copyright
106		** notice, this list of conditions and the following disclaimer.
107		**
108		** 2 Redistributions in binary form must reproduce the above copyright
109		** notice, this list of conditions and the following disclaimer in
110		** the documentation and/or other materials provided with the
111		** distribution.
112		**
113		** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
114		** the International Astronomical Union nor the names of its
115		** contributors may be used to endorse or promote products derived
116		** from this software without specific prior written permission.
117		**
118		** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
119		** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
120		** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
121		** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
122		** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
123		** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
124		** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
125		** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
126		** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
127		** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
128		** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
129		** POSSIBILITY OF SUCH DAMAGE.
130		**
131		*/