File Coverage

erfasrc/src/ab.c

Criterion	Covered	Total	%
statement	0	12	0.0
branch	0	4	0.0
condition			n/a
subroutine			n/a
pod			n/a
total	0	16	0.0

line	stmt	bran	code
1			#include "erfa.h"
2
3	0		void eraAb(double pnat[3], double v[3], double s, double bm1,
4			double ppr[3])
5			/*
6			** - - - - - -
7			** e r a A b
8			** - - - - - -
9			**
10			** Apply aberration to transform natural direction into proper
11			** direction.
12			**
13			** Given:
14			** pnat double[3] natural direction to the source (unit vector)
15			** v double[3] observer barycentric velocity in units of c
16			** s double distance between the Sun and the observer (au)
17			** bm1 double sqrt(1-\|v\|^2): reciprocal of Lorenz factor
18			**
19			** Returned:
20			** ppr double[3] proper direction to source (unit vector)
21			**
22			** Notes:
23			**
24			** 1) The algorithm is based on Expr. (7.40) in the Explanatory
25			** Supplement (Urban & Seidelmann 2013), but with the following
26			** changes:
27			**
28			** o Rigorous rather than approximate normalization is applied.
29			**
30			** o The gravitational potential term from Expr. (7) in
31			** Klioner (2003) is added, taking into account only the Sun's
32			** contribution. This has a maximum effect of about
33			** 0.4 microarcsecond.
34			**
35			** 2) In almost all cases, the maximum accuracy will be limited by the
36			** supplied velocity. For example, if the ERFA eraEpv00 function is
37			** used, errors of up to 5 microarcseconds could occur.
38			**
39			** References:
40			**
41			** Urban, S. & Seidelmann, P. K. (eds), Explanatory Supplement to
42			** the Astronomical Almanac, 3rd ed., University Science Books
43			** (2013).
44			**
45			** Klioner, Sergei A., "A practical relativistic model for micro-
46			** arcsecond astrometry in space", Astr. J. 125, 1580-1597 (2003).
47			**
48			** Called:
49			** eraPdp scalar product of two p-vectors
50			**
51			** Copyright (C) 2013-2019, NumFOCUS Foundation.
52			** Derived, with permission, from the SOFA library. See notes at end of file.
53			*/
54			{
55			int i;
56			double pdv, w1, w2, r2, w, p[3], r;
57
58
59	0		pdv = eraPdp(pnat, v);
60	0		w1 = 1.0 + pdv/(1.0 + bm1);
61	0		w2 = ERFA_SRS/s;
62			r2 = 0.0;
63	0	0	for (i = 0; i < 3; i++) {
64	0		w = pnat[i]bm1 + w1v[i] + w2(v[i] - pdvpnat[i]);
65	0		p[i] = w;
66	0		r2 = r2 + w*w;
67			}
68	0		r = sqrt(r2);
69	0	0	for (i = 0; i < 3; i++) {
70	0		ppr[i] = p[i]/r;
71			}
72
73			/* Finished. */
74
75	0		}
76			/*----------------------------------------------------------------------
77			**
78			**
79			** Copyright (C) 2013-2019, NumFOCUS Foundation.
80			** All rights reserved.
81			**
82			** This library is derived, with permission, from the International
83			** Astronomical Union's "Standards of Fundamental Astronomy" library,
84			** available from http://www.iausofa.org.
85			**
86			** The ERFA version is intended to retain identical functionality to
87			** the SOFA library, but made distinct through different function and
88			** file names, as set out in the SOFA license conditions. The SOFA
89			** original has a role as a reference standard for the IAU and IERS,
90			** and consequently redistribution is permitted only in its unaltered
91			** state. The ERFA version is not subject to this restriction and
92			** therefore can be included in distributions which do not support the
93			** concept of "read only" software.
94			**
95			** Although the intent is to replicate the SOFA API (other than
96			** replacement of prefix names) and results (with the exception of
97			** bugs; any that are discovered will be fixed), SOFA is not
98			** responsible for any errors found in this version of the library.
99			**
100			** If you wish to acknowledge the SOFA heritage, please acknowledge
101			** that you are using a library derived from SOFA, rather than SOFA
102			** itself.
103			**
104			**
105			** TERMS AND CONDITIONS
106			**
107			** Redistribution and use in source and binary forms, with or without
108			** modification, are permitted provided that the following conditions
109			** are met:
110			**
111			** 1 Redistributions of source code must retain the above copyright
112			** notice, this list of conditions and the following disclaimer.
113			**
114			** 2 Redistributions in binary form must reproduce the above copyright
115			** notice, this list of conditions and the following disclaimer in
116			** the documentation and/or other materials provided with the
117			** distribution.
118			**
119			** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
120			** the International Astronomical Union nor the names of its
121			** contributors may be used to endorse or promote products derived
122			** from this software without specific prior written permission.
123			**
124			** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
125			** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
126			** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
127			** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
128			** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
129			** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
130			** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
131			** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
132			** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
133			** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
134			** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
135			** POSSIBILITY OF SUCH DAMAGE.
136			**
137			*/