FACT++  1.0
a2af.c
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1 #include "erfa.h"
2 
3 void eraA2af(int ndp, double angle, char *sign, int idmsf[4])
4 /*
5 ** - - - - - - - -
6 ** e r a A 2 a f
7 ** - - - - - - - -
8 **
9 ** Decompose radians into degrees, arcminutes, arcseconds, fraction.
10 **
11 ** Given:
12 ** ndp int resolution (Note 1)
13 ** angle double angle in radians
14 **
15 ** Returned:
16 ** sign char '+' or '-'
17 ** idmsf int[4] degrees, arcminutes, arcseconds, fraction
18 **
19 ** Called:
20 ** eraD2tf decompose days to hms
21 **
22 ** Notes:
23 **
24 ** 1) The argument ndp is interpreted as follows:
25 **
26 ** ndp resolution
27 ** : ...0000 00 00
28 ** -7 1000 00 00
29 ** -6 100 00 00
30 ** -5 10 00 00
31 ** -4 1 00 00
32 ** -3 0 10 00
33 ** -2 0 01 00
34 ** -1 0 00 10
35 ** 0 0 00 01
36 ** 1 0 00 00.1
37 ** 2 0 00 00.01
38 ** 3 0 00 00.001
39 ** : 0 00 00.000...
40 **
41 ** 2) The largest positive useful value for ndp is determined by the
42 ** size of angle, the format of doubles on the target platform, and
43 ** the risk of overflowing idmsf[3]. On a typical platform, for
44 ** angle up to 2pi, the available floating-point precision might
45 ** correspond to ndp=12. However, the practical limit is typically
46 ** ndp=9, set by the capacity of a 32-bit int, or ndp=4 if int is
47 ** only 16 bits.
48 **
49 ** 3) The absolute value of angle may exceed 2pi. In cases where it
50 ** does not, it is up to the caller to test for and handle the
51 ** case where angle is very nearly 2pi and rounds up to 360 degrees,
52 ** by testing for idmsf[0]=360 and setting idmsf[0-3] to zero.
53 **
54 ** Copyright (C) 2013-2015, NumFOCUS Foundation.
55 ** Derived, with permission, from the SOFA library. See notes at end of file.
56 */
57 {
58 /* Hours to degrees * radians to turns */
59  const double F = 15.0 / ERFA_D2PI;
60 
61 /* Scale then use days to h,m,s function. */
62  eraD2tf(ndp, angle*F, sign, idmsf);
63 
64  return;
65 
66 }
67 /*----------------------------------------------------------------------
68 **
69 **
70 ** Copyright (C) 2013-2015, NumFOCUS Foundation.
71 ** All rights reserved.
72 **
73 ** This library is derived, with permission, from the International
74 ** Astronomical Union's "Standards of Fundamental Astronomy" library,
75 ** available from http://www.iausofa.org.
76 **
77 ** The ERFA version is intended to retain identical functionality to
78 ** the SOFA library, but made distinct through different function and
79 ** file names, as set out in the SOFA license conditions. The SOFA
80 ** original has a role as a reference standard for the IAU and IERS,
81 ** and consequently redistribution is permitted only in its unaltered
82 ** state. The ERFA version is not subject to this restriction and
83 ** therefore can be included in distributions which do not support the
84 ** concept of "read only" software.
85 **
86 ** Although the intent is to replicate the SOFA API (other than
87 ** replacement of prefix names) and results (with the exception of
88 ** bugs; any that are discovered will be fixed), SOFA is not
89 ** responsible for any errors found in this version of the library.
90 **
91 ** If you wish to acknowledge the SOFA heritage, please acknowledge
92 ** that you are using a library derived from SOFA, rather than SOFA
93 ** itself.
94 **
95 **
96 ** TERMS AND CONDITIONS
97 **
98 ** Redistribution and use in source and binary forms, with or without
99 ** modification, are permitted provided that the following conditions
100 ** are met:
101 **
102 ** 1 Redistributions of source code must retain the above copyright
103 ** notice, this list of conditions and the following disclaimer.
104 **
105 ** 2 Redistributions in binary form must reproduce the above copyright
106 ** notice, this list of conditions and the following disclaimer in
107 ** the documentation and/or other materials provided with the
108 ** distribution.
109 **
110 ** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
111 ** the International Astronomical Union nor the names of its
112 ** contributors may be used to endorse or promote products derived
113 ** from this software without specific prior written permission.
114 **
115 ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
116 ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
117 ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
118 ** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
119 ** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
120 ** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
121 ** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
122 ** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
123 ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
124 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
125 ** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
126 ** POSSIBILITY OF SUCH DAMAGE.
127 **
128 */
ERFA_D2PI
#define ERFA_D2PI
Definition: erfam.h:48
eraA2af
void eraA2af(int ndp, double angle, char *sign, int idmsf[4])
Definition: a2af.c:3
eraD2tf
void eraD2tf(int ndp, double days, char *sign, int ihmsf[4])
Definition: d2tf.c:3