File Coverage

erfasrc/src/ee00a.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	double eraEe00a(double date1, double date2)
4		/*
5		** - - - - - - - - -
6		** e r a E e 0 0 a
7		** - - - - - - - - -
8		**
9		** Equation of the equinoxes, compatible with IAU 2000 resolutions.
10		**
11		** Given:
12		** date1,date2 double TT as a 2-part Julian Date (Note 1)
13		**
14		** Returned (function value):
15		** double equation of the equinoxes (Note 2)
16		**
17		** Notes:
18		**
19		** 1) The TT date date1+date2 is a Julian Date, apportioned in any
20		** convenient way between the two arguments. For example,
21		** JD(TT)=2450123.7 could be expressed in any of these ways,
22		** among others:
23		**
24		** date1 date2
25		**
26		** 2450123.7 0.0 (JD method)
27		** 2451545.0 -1421.3 (J2000 method)
28		** 2400000.5 50123.2 (MJD method)
29		** 2450123.5 0.2 (date & time method)
30		**
31		** The JD method is the most natural and convenient to use in
32		** cases where the loss of several decimal digits of resolution
33		** is acceptable. The J2000 method is best matched to the way
34		** the argument is handled internally and will deliver the
35		** optimum resolution. The MJD method and the date & time methods
36		** are both good compromises between resolution and convenience.
37		**
38		** 2) The result, which is in radians, operates in the following sense:
39		**
40		** Greenwich apparent ST = GMST + equation of the equinoxes
41		**
42		** 3) The result is compatible with the IAU 2000 resolutions. For
43		** further details, see IERS Conventions 2003 and Capitaine et al.
44		** (2002).
45		**
46		** Called:
47		** eraPr00 IAU 2000 precession adjustments
48		** eraObl80 mean obliquity, IAU 1980
49		** eraNut00a nutation, IAU 2000A
50		** eraEe00 equation of the equinoxes, IAU 2000
51		**
52		** References:
53		**
54		** Capitaine, N., Wallace, P.T. and McCarthy, D.D., "Expressions to
55		** implement the IAU 2000 definition of UT1", Astronomy &
56		** Astrophysics, 406, 1135-1149 (2003).
57		**
58		** McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003),
59		** IERS Technical Note No. 32, BKG (2004).
60		**
61		** Copyright (C) 2013-2019, NumFOCUS Foundation.
62		** Derived, with permission, from the SOFA library. See notes at end of file.
63		*/
64		{
65		double dpsipr, depspr, epsa, dpsi, deps, ee;
66
67
68		/* IAU 2000 precession-rate adjustments. */
69	0	eraPr00(date1, date2, &dpsipr, &depspr);
70
71		/* Mean obliquity, consistent with IAU 2000 precession-nutation. */
72	0	epsa = eraObl80(date1, date2) + depspr;
73
74		/* Nutation in longitude. */
75	0	eraNut00a(date1, date2, &dpsi, &deps);
76
77		/* Equation of the equinoxes. */
78	0	ee = eraEe00(date1, date2, epsa, dpsi);
79
80	0	return ee;
81
82		}
83		/*----------------------------------------------------------------------
84		**
85		**
86		** Copyright (C) 2013-2019, NumFOCUS Foundation.
87		** All rights reserved.
88		**
89		** This library is derived, with permission, from the International
90		** Astronomical Union's "Standards of Fundamental Astronomy" library,
91		** available from http://www.iausofa.org.
92		**
93		** The ERFA version is intended to retain identical functionality to
94		** the SOFA library, but made distinct through different function and
95		** file names, as set out in the SOFA license conditions. The SOFA
96		** original has a role as a reference standard for the IAU and IERS,
97		** and consequently redistribution is permitted only in its unaltered
98		** state. The ERFA version is not subject to this restriction and
99		** therefore can be included in distributions which do not support the
100		** concept of "read only" software.
101		**
102		** Although the intent is to replicate the SOFA API (other than
103		** replacement of prefix names) and results (with the exception of
104		** bugs; any that are discovered will be fixed), SOFA is not
105		** responsible for any errors found in this version of the library.
106		**
107		** If you wish to acknowledge the SOFA heritage, please acknowledge
108		** that you are using a library derived from SOFA, rather than SOFA
109		** itself.
110		**
111		**
112		** TERMS AND CONDITIONS
113		**
114		** Redistribution and use in source and binary forms, with or without
115		** modification, are permitted provided that the following conditions
116		** are met:
117		**
118		** 1 Redistributions of source code must retain the above copyright
119		** notice, this list of conditions and the following disclaimer.
120		**
121		** 2 Redistributions in binary form must reproduce the above copyright
122		** notice, this list of conditions and the following disclaimer in
123		** the documentation and/or other materials provided with the
124		** distribution.
125		**
126		** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
127		** the International Astronomical Union nor the names of its
128		** contributors may be used to endorse or promote products derived
129		** from this software without specific prior written permission.
130		**
131		** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
132		** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
133		** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
134		** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
135		** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
136		** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
137		** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
138		** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
139		** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
140		** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
141		** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
142		** POSSIBILITY OF SUCH DAMAGE.
143		**
144		*/