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author | William Joye <wjoye@cfa.harvard.edu> | 2019-05-10 18:45:23 (GMT) |
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committer | William Joye <wjoye@cfa.harvard.edu> | 2019-05-10 18:45:23 (GMT) |
commit | 0b1addf5643c828955a6add53f2a4f7a7a813e41 (patch) | |
tree | 94fe32a76399be787746c3c403cca2076a253e29 /ast/erfa/pvxpv.c | |
parent | 75fab9d80911f74aaab738fa9ab8a4f9b0f57a6b (diff) | |
download | blt-0b1addf5643c828955a6add53f2a4f7a7a813e41.zip blt-0b1addf5643c828955a6add53f2a4f7a7a813e41.tar.gz blt-0b1addf5643c828955a6add53f2a4f7a7a813e41.tar.bz2 |
upgrade ast 8.7.1
Diffstat (limited to 'ast/erfa/pvxpv.c')
-rw-r--r-- | ast/erfa/pvxpv.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/ast/erfa/pvxpv.c b/ast/erfa/pvxpv.c new file mode 100644 index 0000000..0d87479 --- /dev/null +++ b/ast/erfa/pvxpv.c @@ -0,0 +1,116 @@ +#include "erfa.h" + +void eraPvxpv(double a[2][3], double b[2][3], double axb[2][3]) +/* +** - - - - - - - - - +** e r a P v x p v +** - - - - - - - - - +** +** Outer (=vector=cross) product of two pv-vectors. +** +** Given: +** a double[2][3] first pv-vector +** b double[2][3] second pv-vector +** +** Returned: +** axb double[2][3] a x b +** +** Notes: +** +** 1) If the position and velocity components of the two pv-vectors are +** ( ap, av ) and ( bp, bv ), the result, a x b, is the pair of +** vectors ( ap x bp, ap x bv + av x bp ). The two vectors are the +** cross-product of the two p-vectors and its derivative. +** +** 2) It is permissible to re-use the same array for any of the +** arguments. +** +** Called: +** eraCpv copy pv-vector +** eraPxp vector product of two p-vectors +** eraPpp p-vector plus p-vector +** +** Copyright (C) 2013-2016, NumFOCUS Foundation. +** Derived, with permission, from the SOFA library. See notes at end of file. +*/ +{ + double wa[2][3], wb[2][3], axbd[3], adxb[3]; + + +/* Make copies of the inputs. */ + eraCpv(a, wa); + eraCpv(b, wb); + +/* a x b = position part of result. */ + eraPxp(wa[0], wb[0], axb[0]); + +/* a x bdot + adot x b = velocity part of result. */ + eraPxp(wa[0], wb[1], axbd); + eraPxp(wa[1], wb[0], adxb); + eraPpp(axbd, adxb, axb[1]); + + return; + +} +/*---------------------------------------------------------------------- +** +** +** Copyright (C) 2013-2016, NumFOCUS Foundation. +** All rights reserved. +** +** This library is derived, with permission, from the International +** Astronomical Union's "Standards of Fundamental Astronomy" library, +** available from http://www.iausofa.org. +** +** The ERFA version is intended to retain identical functionality to +** the SOFA library, but made distinct through different function and +** file names, as set out in the SOFA license conditions. The SOFA +** original has a role as a reference standard for the IAU and IERS, +** and consequently redistribution is permitted only in its unaltered +** state. The ERFA version is not subject to this restriction and +** therefore can be included in distributions which do not support the +** concept of "read only" software. +** +** Although the intent is to replicate the SOFA API (other than +** replacement of prefix names) and results (with the exception of +** bugs; any that are discovered will be fixed), SOFA is not +** responsible for any errors found in this version of the library. +** +** If you wish to acknowledge the SOFA heritage, please acknowledge +** that you are using a library derived from SOFA, rather than SOFA +** itself. +** +** +** TERMS AND CONDITIONS +** +** Redistribution and use in source and binary forms, with or without +** modification, are permitted provided that the following conditions +** are met: +** +** 1 Redistributions of source code must retain the above copyright +** notice, this list of conditions and the following disclaimer. +** +** 2 Redistributions in binary form must reproduce the above copyright +** notice, this list of conditions and the following disclaimer in +** the documentation and/or other materials provided with the +** distribution. +** +** 3 Neither the name of the Standards Of Fundamental Astronomy Board, +** the International Astronomical Union nor the names of its +** contributors may be used to endorse or promote products derived +** from this software without specific prior written permission. +** +** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS +** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE +** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, +** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, +** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN +** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +** POSSIBILITY OF SUCH DAMAGE. +** +*/ |