File Coverage

erfasrc/src/ee06a.c

Criterion	Covered	Total	%
statement	5	5	100.0
branch			n/a
condition			n/a
subroutine			n/a
pod			n/a
total	5	5	100.0

line	stmt	code
1		#include "erfa.h"
2
3	3	double eraEe06a(double date1, double date2)
4		/*
5		** - - - - - - - - -
6		** e r a E e 0 6 a
7		** - - - - - - - - -
8		**
9		** Equation of the equinoxes, compatible with IAU 2000 resolutions and
10		** IAU 2006/2000A precession-nutation.
11		**
12		** Given:
13		** date1,date2 double TT as a 2-part Julian Date (Note 1)
14		**
15		** Returned (function value):
16		** double equation of the equinoxes (Note 2)
17		**
18		** Notes:
19		**
20		** 1) The TT date date1+date2 is a Julian Date, apportioned in any
21		** convenient way between the two arguments. For example,
22		** JD(TT)=2450123.7 could be expressed in any of these ways,
23		** among others:
24		**
25		** date1 date2
26		**
27		** 2450123.7 0.0 (JD method)
28		** 2451545.0 -1421.3 (J2000 method)
29		** 2400000.5 50123.2 (MJD method)
30		** 2450123.5 0.2 (date & time method)
31		**
32		** The JD method is the most natural and convenient to use in
33		** cases where the loss of several decimal digits of resolution
34		** is acceptable. The J2000 method is best matched to the way
35		** the argument is handled internally and will deliver the
36		** optimum resolution. The MJD method and the date & time methods
37		** are both good compromises between resolution and convenience.
38		**
39		** 2) The result, which is in radians, operates in the following sense:
40		**
41		** Greenwich apparent ST = GMST + equation of the equinoxes
42		**
43		** Called:
44		** eraAnpm normalize angle into range +/- pi
45		** eraGst06a Greenwich apparent sidereal time, IAU 2006/2000A
46		** eraGmst06 Greenwich mean sidereal time, IAU 2006
47		**
48		** Reference:
49		**
50		** McCarthy, D. D., Petit, G. (eds.), 2004, IERS Conventions (2003),
51		** IERS Technical Note No. 32, BKG
52		**
53		** Copyright (C) 2013-2019, NumFOCUS Foundation.
54		** Derived, with permission, from the SOFA library. See notes at end of file.
55		*/
56		{
57		double gst06a, gmst06, ee;
58
59
60		/* Apparent and mean sidereal times. */
61	3	gst06a = eraGst06a(0.0, 0.0, date1, date2);
62	3	gmst06 = eraGmst06(0.0, 0.0, date1, date2);
63
64		/* Equation of the equinoxes. */
65	3	ee = eraAnpm(gst06a - gmst06);
66
67	3	return ee;
68
69		}
70		/*----------------------------------------------------------------------
71		**
72		**
73		** Copyright (C) 2013-2019, 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		*/