File Coverage

erfasrc/src/ltpb.c

Criterion	Covered	Total	%
statement	0	7	0.0
branch	0	2	0.0
condition			n/a
subroutine			n/a
pod			n/a
total	0	9	0.0

line	stmt	bran	code
1			#include "erfa.h"
2
3	0		void eraLtpb(double epj, double rpb[3][3])
4			/*
5			** - - - - - - - -
6			** e r a L t p b
7			** - - - - - - - -
8			**
9			** Long-term precession matrix, including ICRS frame bias.
10			**
11			** Given:
12			** epj double Julian epoch (TT)
13			**
14			** Returned:
15			** rpb double[3][3] precession-bias matrix, J2000.0 to date
16			**
17			** Notes:
18			**
19			** 1) The matrix is in the sense
20			**
21			** P_date = rpb x P_ICRS,
22			**
23			** where P_ICRS is a vector in the Geocentric Celestial Reference
24			** System, and P_date is the vector with respect to the Celestial
25			** Intermediate Reference System at that date but with nutation
26			** neglected.
27			**
28			** 2) A first order frame bias formulation is used, of sub-
29			** microarcsecond accuracy compared with a full 3D rotation.
30			**
31			** 3) The Vondrak et al. (2011, 2012) 400 millennia precession model
32			** agrees with the IAU 2006 precession at J2000.0 and stays within
33			** 100 microarcseconds during the 20th and 21st centuries. It is
34			** accurate to a few arcseconds throughout the historical period,
35			** worsening to a few tenths of a degree at the end of the
36			** +/- 200,000 year time span.
37			**
38			** References:
39			**
40			** Vondrak, J., Capitaine, N. and Wallace, P., 2011, New precession
41			** expressions, valid for long time intervals, Astron.Astrophys. 534,
42			** A22
43			**
44			** Vondrak, J., Capitaine, N. and Wallace, P., 2012, New precession
45			** expressions, valid for long time intervals (Corrigendum),
46			** Astron.Astrophys. 541, C1
47			**
48			** Copyright (C) 2013-2019, NumFOCUS Foundation.
49			** Derived, with permission, from the SOFA library. See notes at end of file.
50			*/
51			{
52			/* Frame bias (IERS Conventions 2010, Eqs. 5.21 and 5.33) */
53			const double dx = -0.016617 * ERFA_DAS2R,
54			de = -0.0068192 * ERFA_DAS2R,
55			dr = -0.0146 * ERFA_DAS2R;
56
57			int i;
58			double rp[3][3];
59
60
61			/* Precession matrix. */
62	0		eraLtp(epj, rp);
63
64			/* Apply the bias. */
65	0	0	for ( i = 0; i < 3; i++ ) {
66	0		rpb[i][0] = rp[i][0] - rp[i][1]dr + rp[i][2]dx;
67	0		rpb[i][1] = rp[i][0]dr + rp[i][1] + rp[i][2]de;
68	0		rpb[i][2] = -rp[i][0]dx - rp[i][1]de + rp[i][2];
69			}
70
71	0		}
72			/*----------------------------------------------------------------------
73			**
74			**
75			** Copyright (C) 2013-2019, NumFOCUS Foundation.
76			** All rights reserved.
77			**
78			** This library is derived, with permission, from the International
79			** Astronomical Union's "Standards of Fundamental Astronomy" library,
80			** available from http://www.iausofa.org.
81			**
82			** The ERFA version is intended to retain identical functionality to
83			** the SOFA library, but made distinct through different function and
84			** file names, as set out in the SOFA license conditions. The SOFA
85			** original has a role as a reference standard for the IAU and IERS,
86			** and consequently redistribution is permitted only in its unaltered
87			** state. The ERFA version is not subject to this restriction and
88			** therefore can be included in distributions which do not support the
89			** concept of "read only" software.
90			**
91			** Although the intent is to replicate the SOFA API (other than
92			** replacement of prefix names) and results (with the exception of
93			** bugs; any that are discovered will be fixed), SOFA is not
94			** responsible for any errors found in this version of the library.
95			**
96			** If you wish to acknowledge the SOFA heritage, please acknowledge
97			** that you are using a library derived from SOFA, rather than SOFA
98			** itself.
99			**
100			**
101			** TERMS AND CONDITIONS
102			**
103			** Redistribution and use in source and binary forms, with or without
104			** modification, are permitted provided that the following conditions
105			** are met:
106			**
107			** 1 Redistributions of source code must retain the above copyright
108			** notice, this list of conditions and the following disclaimer.
109			**
110			** 2 Redistributions in binary form must reproduce the above copyright
111			** notice, this list of conditions and the following disclaimer in
112			** the documentation and/or other materials provided with the
113			** distribution.
114			**
115			** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
116			** the International Astronomical Union nor the names of its
117			** contributors may be used to endorse or promote products derived
118			** from this software without specific prior written permission.
119			**
120			** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
121			** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
122			** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
123			** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
124			** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
125			** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
126			** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
127			** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
128			** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
129			** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
130			** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
131			** POSSIBILITY OF SUCH DAMAGE.
132			**
133			*/