FACT++  1.0
s2pv.c
Go to the documentation of this file.
1 #include "erfa.h"
2 
3 void eraS2pv(double theta, double phi, double r,
4  double td, double pd, double rd,
5  double pv[2][3])
6 /*
7 ** - - - - - - - -
8 ** e r a S 2 p v
9 ** - - - - - - - -
10 **
11 ** Convert position/velocity from spherical to Cartesian coordinates.
12 **
13 ** Given:
14 ** theta double longitude angle (radians)
15 ** phi double latitude angle (radians)
16 ** r double radial distance
17 ** td double rate of change of theta
18 ** pd double rate of change of phi
19 ** rd double rate of change of r
20 **
21 ** Returned:
22 ** pv double[2][3] pv-vector
23 **
24 ** Copyright (C) 2013-2015, NumFOCUS Foundation.
25 ** Derived, with permission, from the SOFA library. See notes at end of file.
26 */
27 {
28  double st, ct, sp, cp, rcp, x, y, rpd, w;
29 
30  st = sin(theta);
31  ct = cos(theta);
32  sp = sin(phi);
33  cp = cos(phi);
34  rcp = r * cp;
35  x = rcp * ct;
36  y = rcp * st;
37  rpd = r * pd;
38  w = rpd*sp - cp*rd;
39 
40  pv[0][0] = x;
41  pv[0][1] = y;
42  pv[0][2] = r * sp;
43  pv[1][0] = -y*td - w*ct;
44  pv[1][1] = x*td - w*st;
45  pv[1][2] = rpd*cp + sp*rd;
46 
47  return;
48 
49 }
50 /*----------------------------------------------------------------------
51 **
52 **
53 ** Copyright (C) 2013-2015, NumFOCUS Foundation.
54 ** All rights reserved.
55 **
56 ** This library is derived, with permission, from the International
57 ** Astronomical Union's "Standards of Fundamental Astronomy" library,
58 ** available from http://www.iausofa.org.
59 **
60 ** The ERFA version is intended to retain identical functionality to
61 ** the SOFA library, but made distinct through different function and
62 ** file names, as set out in the SOFA license conditions. The SOFA
63 ** original has a role as a reference standard for the IAU and IERS,
64 ** and consequently redistribution is permitted only in its unaltered
65 ** state. The ERFA version is not subject to this restriction and
66 ** therefore can be included in distributions which do not support the
67 ** concept of "read only" software.
68 **
69 ** Although the intent is to replicate the SOFA API (other than
70 ** replacement of prefix names) and results (with the exception of
71 ** bugs; any that are discovered will be fixed), SOFA is not
72 ** responsible for any errors found in this version of the library.
73 **
74 ** If you wish to acknowledge the SOFA heritage, please acknowledge
75 ** that you are using a library derived from SOFA, rather than SOFA
76 ** itself.
77 **
78 **
79 ** TERMS AND CONDITIONS
80 **
81 ** Redistribution and use in source and binary forms, with or without
82 ** modification, are permitted provided that the following conditions
83 ** are met:
84 **
85 ** 1 Redistributions of source code must retain the above copyright
86 ** notice, this list of conditions and the following disclaimer.
87 **
88 ** 2 Redistributions in binary form must reproduce the above copyright
89 ** notice, this list of conditions and the following disclaimer in
90 ** the documentation and/or other materials provided with the
91 ** distribution.
92 **
93 ** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
94 ** the International Astronomical Union nor the names of its
95 ** contributors may be used to endorse or promote products derived
96 ** from this software without specific prior written permission.
97 **
98 ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
99 ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
100 ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
101 ** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
102 ** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
103 ** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
104 ** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
105 ** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
106 ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
107 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
108 ** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
109 ** POSSIBILITY OF SUCH DAMAGE.
110 **
111 */
eraS2pv
void eraS2pv(double theta, double phi, double r, double td, double pd, double rd, double pv[2][3])
Definition: s2pv.c:3