1 #include "erfa.h"
2
eraRxr(double a[3][3],double b[3][3],double atb[3][3])3 void eraRxr(double a[3][3], double b[3][3], double atb[3][3])
4 /*
5 ** - - - - - - -
6 ** e r a R x r
7 ** - - - - - - -
8 **
9 ** Multiply two r-matrices.
10 **
11 ** Given:
12 ** a double[3][3] first r-matrix
13 ** b double[3][3] second r-matrix
14 **
15 ** Returned:
16 ** atb double[3][3] a * b
17 **
18 ** Note:
19 ** It is permissible to re-use the same array for any of the
20 ** arguments.
21 **
22 ** Called:
23 ** eraCr copy r-matrix
24 **
25 ** Copyright (C) 2013-2014, NumFOCUS Foundation.
26 ** Derived, with permission, from the SOFA library. See notes at end of file.
27 */
28 {
29 int i, j, k;
30 double w, wm[3][3];
31
32
33 for (i = 0; i < 3; i++) {
34 for (j = 0; j < 3; j++) {
35 w = 0.0;
36 for (k = 0; k < 3; k++) {
37 w += a[i][k] * b[k][j];
38 }
39 wm[i][j] = w;
40 }
41 }
42 eraCr(wm, atb);
43
44 return;
45
46 }
47 /*----------------------------------------------------------------------
48 **
49 **
50 ** Copyright (C) 2013-2014, NumFOCUS Foundation.
51 ** All rights reserved.
52 **
53 ** This library is derived, with permission, from the International
54 ** Astronomical Union's "Standards of Fundamental Astronomy" library,
55 ** available from http://www.iausofa.org.
56 **
57 ** The ERFA version is intended to retain identical functionality to
58 ** the SOFA library, but made distinct through different function and
59 ** file names, as set out in the SOFA license conditions. The SOFA
60 ** original has a role as a reference standard for the IAU and IERS,
61 ** and consequently redistribution is permitted only in its unaltered
62 ** state. The ERFA version is not subject to this restriction and
63 ** therefore can be included in distributions which do not support the
64 ** concept of "read only" software.
65 **
66 ** Although the intent is to replicate the SOFA API (other than
67 ** replacement of prefix names) and results (with the exception of
68 ** bugs; any that are discovered will be fixed), SOFA is not
69 ** responsible for any errors found in this version of the library.
70 **
71 ** If you wish to acknowledge the SOFA heritage, please acknowledge
72 ** that you are using a library derived from SOFA, rather than SOFA
73 ** itself.
74 **
75 **
76 ** TERMS AND CONDITIONS
77 **
78 ** Redistribution and use in source and binary forms, with or without
79 ** modification, are permitted provided that the following conditions
80 ** are met:
81 **
82 ** 1 Redistributions of source code must retain the above copyright
83 ** notice, this list of conditions and the following disclaimer.
84 **
85 ** 2 Redistributions in binary form must reproduce the above copyright
86 ** notice, this list of conditions and the following disclaimer in
87 ** the documentation and/or other materials provided with the
88 ** distribution.
89 **
90 ** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
91 ** the International Astronomical Union nor the names of its
92 ** contributors may be used to endorse or promote products derived
93 ** from this software without specific prior written permission.
94 **
95 ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
96 ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
97 ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
98 ** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
99 ** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
100 ** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
101 ** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
102 ** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
103 ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
104 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
105 ** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
106 ** POSSIBILITY OF SUCH DAMAGE.
107 **
108 */
109