FACT++  1.0
pxp.c
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1 #include "erfa.h"
2 
3 void eraPxp(double a[3], double b[3], double axb[3])
4 /*
5 ** - - - - - - -
6 ** e r a P x p
7 ** - - - - - - -
8 **
9 ** p-vector outer (=vector=cross) product.
10 **
11 ** Given:
12 ** a double[3] first p-vector
13 ** b double[3] second p-vector
14 **
15 ** Returned:
16 ** axb double[3] a x b
17 **
18 ** Note:
19 ** It is permissible to re-use the same array for any of the
20 ** arguments.
21 **
22 ** Copyright (C) 2013-2015, NumFOCUS Foundation.
23 ** Derived, with permission, from the SOFA library. See notes at end of file.
24 */
25 {
26  double xa, ya, za, xb, yb, zb;
27 
28  xa = a[0];
29  ya = a[1];
30  za = a[2];
31  xb = b[0];
32  yb = b[1];
33  zb = b[2];
34  axb[0] = ya*zb - za*yb;
35  axb[1] = za*xb - xa*zb;
36  axb[2] = xa*yb - ya*xb;
37 
38  return;
39 
40 }
41 /*----------------------------------------------------------------------
42 **
43 **
44 ** Copyright (C) 2013-2015, NumFOCUS Foundation.
45 ** All rights reserved.
46 **
47 ** This library is derived, with permission, from the International
48 ** Astronomical Union's "Standards of Fundamental Astronomy" library,
49 ** available from http://www.iausofa.org.
50 **
51 ** The ERFA version is intended to retain identical functionality to
52 ** the SOFA library, but made distinct through different function and
53 ** file names, as set out in the SOFA license conditions. The SOFA
54 ** original has a role as a reference standard for the IAU and IERS,
55 ** and consequently redistribution is permitted only in its unaltered
56 ** state. The ERFA version is not subject to this restriction and
57 ** therefore can be included in distributions which do not support the
58 ** concept of "read only" software.
59 **
60 ** Although the intent is to replicate the SOFA API (other than
61 ** replacement of prefix names) and results (with the exception of
62 ** bugs; any that are discovered will be fixed), SOFA is not
63 ** responsible for any errors found in this version of the library.
64 **
65 ** If you wish to acknowledge the SOFA heritage, please acknowledge
66 ** that you are using a library derived from SOFA, rather than SOFA
67 ** itself.
68 **
69 **
70 ** TERMS AND CONDITIONS
71 **
72 ** Redistribution and use in source and binary forms, with or without
73 ** modification, are permitted provided that the following conditions
74 ** are met:
75 **
76 ** 1 Redistributions of source code must retain the above copyright
77 ** notice, this list of conditions and the following disclaimer.
78 **
79 ** 2 Redistributions in binary form must reproduce the above copyright
80 ** notice, this list of conditions and the following disclaimer in
81 ** the documentation and/or other materials provided with the
82 ** distribution.
83 **
84 ** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
85 ** the International Astronomical Union nor the names of its
86 ** contributors may be used to endorse or promote products derived
87 ** from this software without specific prior written permission.
88 **
89 ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
90 ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
91 ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
92 ** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
93 ** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
94 ** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
95 ** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
96 ** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
97 ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
98 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
99 ** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
100 ** POSSIBILITY OF SUCH DAMAGE.
101 **
102 */
eraPxp
void eraPxp(double a[3], double b[3], double axb[3])
Definition: pxp.c:3