File Coverage

erfasrc/src/pom00.c

Criterion	Covered	Total	%
statement	0	6	0.0
branch			n/a
condition			n/a
subroutine			n/a
pod			n/a
total	0	6	0.0

line	stmt	code
1		#include "erfa.h"
2
3	0	void eraPom00(double xp, double yp, double sp, double rpom[3][3])
4		/*
5		** - - - - - - - - - -
6		** e r a P o m 0 0
7		** - - - - - - - - - -
8		**
9		** Form the matrix of polar motion for a given date, IAU 2000.
10		**
11		** Given:
12		** xp,yp double coordinates of the pole (radians, Note 1)
13		** sp double the TIO locator s' (radians, Note 2)
14		**
15		** Returned:
16		** rpom double[3][3] polar-motion matrix (Note 3)
17		**
18		** Notes:
19		**
20		** 1) The arguments xp and yp are the coordinates (in radians) of the
21		** Celestial Intermediate Pole with respect to the International
22		** Terrestrial Reference System (see IERS Conventions 2003),
23		** measured along the meridians to 0 and 90 deg west respectively.
24		**
25		** 2) The argument sp is the TIO locator s', in radians, which
26		** positions the Terrestrial Intermediate Origin on the equator. It
27		** is obtained from polar motion observations by numerical
28		** integration, and so is in essence unpredictable. However, it is
29		** dominated by a secular drift of about 47 microarcseconds per
30		** century, and so can be taken into account by using s' = -47*t,
31		** where t is centuries since J2000.0. The function eraSp00
32		** implements this approximation.
33		**
34		** 3) The matrix operates in the sense V(TRS) = rpom * V(CIP), meaning
35		** that it is the final rotation when computing the pointing
36		** direction to a celestial source.
37		**
38		** Called:
39		** eraIr initialize r-matrix to identity
40		** eraRz rotate around Z-axis
41		** eraRy rotate around Y-axis
42		** eraRx rotate around X-axis
43		**
44		** Reference:
45		**
46		** McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003),
47		** IERS Technical Note No. 32, BKG (2004)
48		**
49		** Copyright (C) 2013-2019, NumFOCUS Foundation.
50		** Derived, with permission, from the SOFA library. See notes at end of file.
51		*/
52		{
53
54		/* Construct the matrix. */
55	0	eraIr(rpom);
56	0	eraRz(sp, rpom);
57	0	eraRy(-xp, rpom);
58	0	eraRx(-yp, rpom);
59
60	0	return;
61
62		}
63		/*----------------------------------------------------------------------
64		**
65		**
66		** Copyright (C) 2013-2019, NumFOCUS Foundation.
67		** All rights reserved.
68		**
69		** This library is derived, with permission, from the International
70		** Astronomical Union's "Standards of Fundamental Astronomy" library,
71		** available from http://www.iausofa.org.
72		**
73		** The ERFA version is intended to retain identical functionality to
74		** the SOFA library, but made distinct through different function and
75		** file names, as set out in the SOFA license conditions. The SOFA
76		** original has a role as a reference standard for the IAU and IERS,
77		** and consequently redistribution is permitted only in its unaltered
78		** state. The ERFA version is not subject to this restriction and
79		** therefore can be included in distributions which do not support the
80		** concept of "read only" software.
81		**
82		** Although the intent is to replicate the SOFA API (other than
83		** replacement of prefix names) and results (with the exception of
84		** bugs; any that are discovered will be fixed), SOFA is not
85		** responsible for any errors found in this version of the library.
86		**
87		** If you wish to acknowledge the SOFA heritage, please acknowledge
88		** that you are using a library derived from SOFA, rather than SOFA
89		** itself.
90		**
91		**
92		** TERMS AND CONDITIONS
93		**
94		** Redistribution and use in source and binary forms, with or without
95		** modification, are permitted provided that the following conditions
96		** are met:
97		**
98		** 1 Redistributions of source code must retain the above copyright
99		** notice, this list of conditions and the following disclaimer.
100		**
101		** 2 Redistributions in binary form must reproduce the above copyright
102		** notice, this list of conditions and the following disclaimer in
103		** the documentation and/or other materials provided with the
104		** distribution.
105		**
106		** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
107		** the International Astronomical Union nor the names of its
108		** contributors may be used to endorse or promote products derived
109		** from this software without specific prior written permission.
110		**
111		** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
112		** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
113		** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
114		** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
115		** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
116		** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
117		** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
118		** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
119		** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
120		** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
121		** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
122		** POSSIBILITY OF SUCH DAMAGE.
123		**
124		*/