File Coverage

erfasrc/src/tttai.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 cond sub pod time code
1             #include "erfa.h"
2              
3 0           int eraTttai(double tt1, double tt2, double *tai1, double *tai2)
4             /*
5             ** - - - - - - - - -
6             ** e r a T t t a i
7             ** - - - - - - - - -
8             **
9             ** Time scale transformation: Terrestrial Time, TT, to International
10             ** Atomic Time, TAI.
11             **
12             ** Given:
13             ** tt1,tt2 double TT as a 2-part Julian Date
14             **
15             ** Returned:
16             ** tai1,tai2 double TAI as a 2-part Julian Date
17             **
18             ** Returned (function value):
19             ** int status: 0 = OK
20             **
21             ** Note:
22             **
23             ** tt1+tt2 is Julian Date, apportioned in any convenient way between
24             ** the two arguments, for example where tt1 is the Julian Day Number
25             ** and tt2 is the fraction of a day. The returned tai1,tai2 follow
26             ** suit.
27             **
28             ** References:
29             **
30             ** McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003),
31             ** IERS Technical Note No. 32, BKG (2004)
32             **
33             ** Explanatory Supplement to the Astronomical Almanac,
34             ** P. Kenneth Seidelmann (ed), University Science Books (1992)
35             **
36             ** Copyright (C) 2013-2020, NumFOCUS Foundation.
37             ** Derived, with permission, from the SOFA library. See notes at end of file.
38             */
39             {
40              
41             /* TT minus TAI (days). */
42             static const double dtat = ERFA_TTMTAI/ERFA_DAYSEC;
43              
44              
45             /* Result, safeguarding precision. */
46 0 0         if ( fabs(tt1) > fabs(tt2) ) {
47 0           *tai1 = tt1;
48 0           *tai2 = tt2 - dtat;
49             } else {
50 0           *tai1 = tt1 - dtat;
51 0           *tai2 = tt2;
52             }
53              
54             /* Status (always OK). */
55 0           return 0;
56              
57             }
58             /*----------------------------------------------------------------------
59             **
60             **
61             ** Copyright (C) 2013-2020, NumFOCUS Foundation.
62             ** All rights reserved.
63             **
64             ** This library is derived, with permission, from the International
65             ** Astronomical Union's "Standards of Fundamental Astronomy" library,
66             ** available from http://www.iausofa.org.
67             **
68             ** The ERFA version is intended to retain identical functionality to
69             ** the SOFA library, but made distinct through different function and
70             ** file names, as set out in the SOFA license conditions. The SOFA
71             ** original has a role as a reference standard for the IAU and IERS,
72             ** and consequently redistribution is permitted only in its unaltered
73             ** state. The ERFA version is not subject to this restriction and
74             ** therefore can be included in distributions which do not support the
75             ** concept of "read only" software.
76             **
77             ** Although the intent is to replicate the SOFA API (other than
78             ** replacement of prefix names) and results (with the exception of
79             ** bugs; any that are discovered will be fixed), SOFA is not
80             ** responsible for any errors found in this version of the library.
81             **
82             ** If you wish to acknowledge the SOFA heritage, please acknowledge
83             ** that you are using a library derived from SOFA, rather than SOFA
84             ** itself.
85             **
86             **
87             ** TERMS AND CONDITIONS
88             **
89             ** Redistribution and use in source and binary forms, with or without
90             ** modification, are permitted provided that the following conditions
91             ** are met:
92             **
93             ** 1 Redistributions of source code must retain the above copyright
94             ** notice, this list of conditions and the following disclaimer.
95             **
96             ** 2 Redistributions in binary form must reproduce the above copyright
97             ** notice, this list of conditions and the following disclaimer in
98             ** the documentation and/or other materials provided with the
99             ** distribution.
100             **
101             ** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
102             ** the International Astronomical Union nor the names of its
103             ** contributors may be used to endorse or promote products derived
104             ** from this software without specific prior written permission.
105             **
106             ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
107             ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
108             ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
109             ** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
110             ** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
111             ** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
112             ** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
113             ** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
114             ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
115             ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
116             ** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
117             ** POSSIBILITY OF SUCH DAMAGE.
118             **
119             */