1 | #include "erfa.h"
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2 |
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3 | void eraA2af(int ndp, double angle, char *sign, int idmsf[4])
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4 | /*
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5 | ** - - - - - - - -
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6 | ** e r a A 2 a f
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7 | ** - - - - - - - -
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8 | **
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9 | ** Decompose radians into degrees, arcminutes, arcseconds, fraction.
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10 | **
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11 | ** Given:
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12 | ** ndp int resolution (Note 1)
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13 | ** angle double angle in radians
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14 | **
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15 | ** Returned:
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16 | ** sign char '+' or '-'
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17 | ** idmsf int[4] degrees, arcminutes, arcseconds, fraction
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18 | **
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19 | ** Called:
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20 | ** eraD2tf decompose days to hms
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21 | **
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22 | ** Notes:
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23 | **
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24 | ** 1) The argument ndp is interpreted as follows:
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25 | **
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26 | ** ndp resolution
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27 | ** : ...0000 00 00
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28 | ** -7 1000 00 00
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29 | ** -6 100 00 00
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30 | ** -5 10 00 00
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31 | ** -4 1 00 00
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32 | ** -3 0 10 00
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33 | ** -2 0 01 00
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34 | ** -1 0 00 10
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35 | ** 0 0 00 01
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36 | ** 1 0 00 00.1
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37 | ** 2 0 00 00.01
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38 | ** 3 0 00 00.001
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39 | ** : 0 00 00.000...
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40 | **
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41 | ** 2) The largest positive useful value for ndp is determined by the
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42 | ** size of angle, the format of doubles on the target platform, and
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43 | ** the risk of overflowing idmsf[3]. On a typical platform, for
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44 | ** angle up to 2pi, the available floating-point precision might
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45 | ** correspond to ndp=12. However, the practical limit is typically
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46 | ** ndp=9, set by the capacity of a 32-bit int, or ndp=4 if int is
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47 | ** only 16 bits.
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48 | **
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49 | ** 3) The absolute value of angle may exceed 2pi. In cases where it
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50 | ** does not, it is up to the caller to test for and handle the
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51 | ** case where angle is very nearly 2pi and rounds up to 360 degrees,
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52 | ** by testing for idmsf[0]=360 and setting idmsf[0-3] to zero.
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53 | **
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54 | ** Copyright (C) 2013-2016, NumFOCUS Foundation.
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55 | ** Derived, with permission, from the SOFA library. See notes at end of file.
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56 | */
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57 | {
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58 | /* Hours to degrees * radians to turns */
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59 | const double F = 15.0 / ERFA_D2PI;
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60 |
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61 |
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62 | /* Scale then use days to h,m,s function. */
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63 | eraD2tf(ndp, angle*F, sign, idmsf);
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64 |
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65 | return;
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66 |
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67 | }
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68 | /*----------------------------------------------------------------------
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69 | **
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70 | **
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71 | ** Copyright (C) 2013-2016, NumFOCUS Foundation.
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72 | ** All rights reserved.
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73 | **
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74 | ** This library is derived, with permission, from the International
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75 | ** Astronomical Union's "Standards of Fundamental Astronomy" library,
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76 | ** available from http://www.iausofa.org.
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77 | **
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78 | ** The ERFA version is intended to retain identical functionality to
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79 | ** the SOFA library, but made distinct through different function and
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80 | ** file names, as set out in the SOFA license conditions. The SOFA
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81 | ** original has a role as a reference standard for the IAU and IERS,
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82 | ** and consequently redistribution is permitted only in its unaltered
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83 | ** state. The ERFA version is not subject to this restriction and
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84 | ** therefore can be included in distributions which do not support the
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85 | ** concept of "read only" software.
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86 | **
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87 | ** Although the intent is to replicate the SOFA API (other than
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88 | ** replacement of prefix names) and results (with the exception of
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89 | ** bugs; any that are discovered will be fixed), SOFA is not
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90 | ** responsible for any errors found in this version of the library.
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91 | **
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92 | ** If you wish to acknowledge the SOFA heritage, please acknowledge
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93 | ** that you are using a library derived from SOFA, rather than SOFA
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94 | ** itself.
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95 | **
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96 | **
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97 | ** TERMS AND CONDITIONS
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98 | **
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99 | ** Redistribution and use in source and binary forms, with or without
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100 | ** modification, are permitted provided that the following conditions
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101 | ** are met:
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102 | **
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103 | ** 1 Redistributions of source code must retain the above copyright
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104 | ** notice, this list of conditions and the following disclaimer.
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105 | **
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106 | ** 2 Redistributions in binary form must reproduce the above copyright
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107 | ** notice, this list of conditions and the following disclaimer in
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108 | ** the documentation and/or other materials provided with the
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109 | ** distribution.
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110 | **
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111 | ** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
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112 | ** the International Astronomical Union nor the names of its
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113 | ** contributors may be used to endorse or promote products derived
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114 | ** from this software without specific prior written permission.
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115 | **
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116 | ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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117 | ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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118 | ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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119 | ** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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120 | ** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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121 | ** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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122 | ** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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123 | ** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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124 | ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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125 | ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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126 | ** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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127 | ** POSSIBILITY OF SUCH DAMAGE.
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128 | **
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129 | */
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