FACT++  1.0
pn06a.c
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1 #include "erfa.h"
2 
3 void eraPn06a(double date1, double date2,
4  double *dpsi, double *deps, double *epsa,
5  double rb[3][3], double rp[3][3], double rbp[3][3],
6  double rn[3][3], double rbpn[3][3])
7 /*
8 ** - - - - - - - - -
9 ** e r a P n 0 6 a
10 ** - - - - - - - - -
11 **
12 ** Precession-nutation, IAU 2006/2000A models: a multi-purpose function,
13 ** supporting classical (equinox-based) use directly and CIO-based use
14 ** indirectly.
15 **
16 ** Given:
17 ** date1,date2 double TT as a 2-part Julian Date (Note 1)
18 **
19 ** Returned:
20 ** dpsi,deps double nutation (Note 2)
21 ** epsa double mean obliquity (Note 3)
22 ** rb double[3][3] frame bias matrix (Note 4)
23 ** rp double[3][3] precession matrix (Note 5)
24 ** rbp double[3][3] bias-precession matrix (Note 6)
25 ** rn double[3][3] nutation matrix (Note 7)
26 ** rbpn double[3][3] GCRS-to-true matrix (Notes 8,9)
27 **
28 ** Notes:
29 **
30 ** 1) The TT date date1+date2 is a Julian Date, apportioned in any
31 ** convenient way between the two arguments. For example,
32 ** JD(TT)=2450123.7 could be expressed in any of these ways,
33 ** among others:
34 **
35 ** date1 date2
36 **
37 ** 2450123.7 0.0 (JD method)
38 ** 2451545.0 -1421.3 (J2000 method)
39 ** 2400000.5 50123.2 (MJD method)
40 ** 2450123.5 0.2 (date & time method)
41 **
42 ** The JD method is the most natural and convenient to use in
43 ** cases where the loss of several decimal digits of resolution
44 ** is acceptable. The J2000 method is best matched to the way
45 ** the argument is handled internally and will deliver the
46 ** optimum resolution. The MJD method and the date & time methods
47 ** are both good compromises between resolution and convenience.
48 **
49 ** 2) The nutation components (luni-solar + planetary, IAU 2000A) in
50 ** longitude and obliquity are in radians and with respect to the
51 ** equinox and ecliptic of date. Free core nutation is omitted;
52 ** for the utmost accuracy, use the eraPn06 function, where the
53 ** nutation components are caller-specified.
54 **
55 ** 3) The mean obliquity is consistent with the IAU 2006 precession.
56 **
57 ** 4) The matrix rb transforms vectors from GCRS to mean J2000.0 by
58 ** applying frame bias.
59 **
60 ** 5) The matrix rp transforms vectors from mean J2000.0 to mean of
61 ** date by applying precession.
62 **
63 ** 6) The matrix rbp transforms vectors from GCRS to mean of date by
64 ** applying frame bias then precession. It is the product rp x rb.
65 **
66 ** 7) The matrix rn transforms vectors from mean of date to true of
67 ** date by applying the nutation (luni-solar + planetary).
68 **
69 ** 8) The matrix rbpn transforms vectors from GCRS to true of date
70 ** (CIP/equinox). It is the product rn x rbp, applying frame bias,
71 ** precession and nutation in that order.
72 **
73 ** 9) The X,Y,Z coordinates of the IAU 2006/2000A Celestial
74 ** Intermediate Pole are elements (3,1-3) of the GCRS-to-true
75 ** matrix, i.e. rbpn[2][0-2].
76 **
77 ** 10) It is permissible to re-use the same array in the returned
78 ** arguments. The arrays are filled in the stated order.
79 **
80 ** Called:
81 ** eraNut06a nutation, IAU 2006/2000A
82 ** eraPn06 bias/precession/nutation results, IAU 2006
83 **
84 ** Reference:
85 **
86 ** Capitaine, N. & Wallace, P.T., 2006, Astron.Astrophys. 450, 855
87 **
88 ** Copyright (C) 2013-2015, NumFOCUS Foundation.
89 ** Derived, with permission, from the SOFA library. See notes at end of file.
90 */
91 {
92 /* Nutation. */
93  eraNut06a(date1, date2, dpsi, deps);
94 
95 /* Remaining results. */
96  eraPn06(date1, date2, *dpsi, *deps, epsa, rb, rp, rbp, rn, rbpn);
97 
98  return;
99 
100 }
101 /*----------------------------------------------------------------------
102 **
103 **
104 ** Copyright (C) 2013-2015, NumFOCUS Foundation.
105 ** All rights reserved.
106 **
107 ** This library is derived, with permission, from the International
108 ** Astronomical Union's "Standards of Fundamental Astronomy" library,
109 ** available from http://www.iausofa.org.
110 **
111 ** The ERFA version is intended to retain identical functionality to
112 ** the SOFA library, but made distinct through different function and
113 ** file names, as set out in the SOFA license conditions. The SOFA
114 ** original has a role as a reference standard for the IAU and IERS,
115 ** and consequently redistribution is permitted only in its unaltered
116 ** state. The ERFA version is not subject to this restriction and
117 ** therefore can be included in distributions which do not support the
118 ** concept of "read only" software.
119 **
120 ** Although the intent is to replicate the SOFA API (other than
121 ** replacement of prefix names) and results (with the exception of
122 ** bugs; any that are discovered will be fixed), SOFA is not
123 ** responsible for any errors found in this version of the library.
124 **
125 ** If you wish to acknowledge the SOFA heritage, please acknowledge
126 ** that you are using a library derived from SOFA, rather than SOFA
127 ** itself.
128 **
129 **
130 ** TERMS AND CONDITIONS
131 **
132 ** Redistribution and use in source and binary forms, with or without
133 ** modification, are permitted provided that the following conditions
134 ** are met:
135 **
136 ** 1 Redistributions of source code must retain the above copyright
137 ** notice, this list of conditions and the following disclaimer.
138 **
139 ** 2 Redistributions in binary form must reproduce the above copyright
140 ** notice, this list of conditions and the following disclaimer in
141 ** the documentation and/or other materials provided with the
142 ** distribution.
143 **
144 ** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
145 ** the International Astronomical Union nor the names of its
146 ** contributors may be used to endorse or promote products derived
147 ** from this software without specific prior written permission.
148 **
149 ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
150 ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
151 ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
152 ** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
153 ** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
154 ** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
155 ** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
156 ** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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160 ** POSSIBILITY OF SUCH DAMAGE.
161 **
162 */
eraNut06a
void eraNut06a(double date1, double date2, double *dpsi, double *deps)
Definition: nut06a.c:3
eraPn06a
void eraPn06a(double date1, double date2, double *dpsi, double *deps, double *epsa, double rb[3][3], double rp[3][3], double rbp[3][3], double rn[3][3], double rbpn[3][3])
Definition: pn06a.c:3
eraPn06
void eraPn06(double date1, double date2, double dpsi, double deps, double *epsa, double rb[3][3], double rp[3][3], double rbp[3][3], double rn[3][3], double rbpn[3][3])
Definition: pn06.c:3