source: trunk/FACT++/erfa/src/bp06.c@ 18679

Last change on this file since 18679 was 18348, checked in by tbretz, 9 years ago
File size: 5.7 KB
Line 
1#include "erfa.h"
2
3void eraBp06(double date1, double date2,
4 double rb[3][3], double rp[3][3], double rbp[3][3])
5/*
6** - - - - - - - -
7** e r a B p 0 6
8** - - - - - - - -
9**
10** Frame bias and precession, IAU 2006.
11**
12** Given:
13** date1,date2 double TT as a 2-part Julian Date (Note 1)
14**
15** Returned:
16** rb double[3][3] frame bias matrix (Note 2)
17** rp double[3][3] precession matrix (Note 3)
18** rbp double[3][3] bias-precession matrix (Note 4)
19**
20** Notes:
21**
22** 1) The TT date date1+date2 is a Julian Date, apportioned in any
23** convenient way between the two arguments. For example,
24** JD(TT)=2450123.7 could be expressed in any of these ways,
25** among others:
26**
27** date1 date2
28**
29** 2450123.7 0.0 (JD method)
30** 2451545.0 -1421.3 (J2000 method)
31** 2400000.5 50123.2 (MJD method)
32** 2450123.5 0.2 (date & time method)
33**
34** The JD method is the most natural and convenient to use in
35** cases where the loss of several decimal digits of resolution
36** is acceptable. The J2000 method is best matched to the way
37** the argument is handled internally and will deliver the
38** optimum resolution. The MJD method and the date & time methods
39** are both good compromises between resolution and convenience.
40**
41** 2) The matrix rb transforms vectors from GCRS to mean J2000.0 by
42** applying frame bias.
43**
44** 3) The matrix rp transforms vectors from mean J2000.0 to mean of
45** date by applying precession.
46**
47** 4) The matrix rbp transforms vectors from GCRS to mean of date by
48** applying frame bias then precession. It is the product rp x rb.
49**
50** 5) It is permissible to re-use the same array in the returned
51** arguments. The arrays are filled in the order given.
52**
53** Called:
54** eraPfw06 bias-precession F-W angles, IAU 2006
55** eraFw2m F-W angles to r-matrix
56** eraPmat06 PB matrix, IAU 2006
57** eraTr transpose r-matrix
58** eraRxr product of two r-matrices
59** eraCr copy r-matrix
60**
61** References:
62**
63** Capitaine, N. & Wallace, P.T., 2006, Astron.Astrophys. 450, 855
64**
65** Wallace, P.T. & Capitaine, N., 2006, Astron.Astrophys. 459, 981
66**
67** Copyright (C) 2013-2015, NumFOCUS Foundation.
68** Derived, with permission, from the SOFA library. See notes at end of file.
69*/
70{
71 double gamb, phib, psib, epsa, rbpw[3][3], rbt[3][3];
72
73/* B matrix. */
74 eraPfw06(ERFA_DJM0, ERFA_DJM00, &gamb, &phib, &psib, &epsa);
75 eraFw2m(gamb, phib, psib, epsa, rb);
76
77/* PxB matrix (temporary). */
78 eraPmat06(date1, date2, rbpw);
79
80/* P matrix. */
81 eraTr(rb, rbt);
82 eraRxr(rbpw, rbt, rp);
83
84/* PxB matrix. */
85 eraCr(rbpw, rbp);
86
87 return;
88
89}
90/*----------------------------------------------------------------------
91**
92**
93** Copyright (C) 2013-2015, NumFOCUS Foundation.
94** All rights reserved.
95**
96** This library is derived, with permission, from the International
97** Astronomical Union's "Standards of Fundamental Astronomy" library,
98** available from http://www.iausofa.org.
99**
100** The ERFA version is intended to retain identical functionality to
101** the SOFA library, but made distinct through different function and
102** file names, as set out in the SOFA license conditions. The SOFA
103** original has a role as a reference standard for the IAU and IERS,
104** and consequently redistribution is permitted only in its unaltered
105** state. The ERFA version is not subject to this restriction and
106** therefore can be included in distributions which do not support the
107** concept of "read only" software.
108**
109** Although the intent is to replicate the SOFA API (other than
110** replacement of prefix names) and results (with the exception of
111** bugs; any that are discovered will be fixed), SOFA is not
112** responsible for any errors found in this version of the library.
113**
114** If you wish to acknowledge the SOFA heritage, please acknowledge
115** that you are using a library derived from SOFA, rather than SOFA
116** itself.
117**
118**
119** TERMS AND CONDITIONS
120**
121** Redistribution and use in source and binary forms, with or without
122** modification, are permitted provided that the following conditions
123** are met:
124**
125** 1 Redistributions of source code must retain the above copyright
126** notice, this list of conditions and the following disclaimer.
127**
128** 2 Redistributions in binary form must reproduce the above copyright
129** notice, this list of conditions and the following disclaimer in
130** the documentation and/or other materials provided with the
131** distribution.
132**
133** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
134** the International Astronomical Union nor the names of its
135** contributors may be used to endorse or promote products derived
136** from this software without specific prior written permission.
137**
138** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
139** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
140** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
141** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
142** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
143** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
144** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
145** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
146** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
147** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
148** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
149** POSSIBILITY OF SUCH DAMAGE.
150**
151*/
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