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Diffstat (limited to 'ast/erfa/ld.c')
| -rw-r--r-- | ast/erfa/ld.c | 161 |
1 files changed, 0 insertions, 161 deletions
diff --git a/ast/erfa/ld.c b/ast/erfa/ld.c deleted file mode 100644 index c1569fd..0000000 --- a/ast/erfa/ld.c +++ /dev/null @@ -1,161 +0,0 @@ -#include "erfa.h" - -void eraLd(double bm, double p[3], double q[3], double e[3], - double em, double dlim, double p1[3]) -/* -** - - - - - - -** e r a L d -** - - - - - - -** -** Apply light deflection by a solar-system body, as part of -** transforming coordinate direction into natural direction. -** -** Given: -** bm double mass of the gravitating body (solar masses) -** p double[3] direction from observer to source (unit vector) -** q double[3] direction from body to source (unit vector) -** e double[3] direction from body to observer (unit vector) -** em double distance from body to observer (au) -** dlim double deflection limiter (Note 4) -** -** Returned: -** p1 double[3] observer to deflected source (unit vector) -** -** Notes: -** -** 1) The algorithm is based on Expr. (70) in Klioner (2003) and -** Expr. (7.63) in the Explanatory Supplement (Urban & Seidelmann -** 2013), with some rearrangement to minimize the effects of machine -** precision. -** -** 2) The mass parameter bm can, as required, be adjusted in order to -** allow for such effects as quadrupole field. -** -** 3) The barycentric position of the deflecting body should ideally -** correspond to the time of closest approach of the light ray to -** the body. -** -** 4) The deflection limiter parameter dlim is phi^2/2, where phi is -** the angular separation (in radians) between source and body at -** which limiting is applied. As phi shrinks below the chosen -** threshold, the deflection is artificially reduced, reaching zero -** for phi = 0. -** -** 5) The returned vector p1 is not normalized, but the consequential -** departure from unit magnitude is always negligible. -** -** 6) The arguments p and p1 can be the same array. -** -** 7) To accumulate total light deflection taking into account the -** contributions from several bodies, call the present function for -** each body in succession, in decreasing order of distance from the -** observer. -** -** 8) For efficiency, validation is omitted. The supplied vectors must -** be of unit magnitude, and the deflection limiter non-zero and -** positive. -** -** References: -** -** Urban, S. & Seidelmann, P. K. (eds), Explanatory Supplement to -** the Astronomical Almanac, 3rd ed., University Science Books -** (2013). -** -** Klioner, Sergei A., "A practical relativistic model for micro- -** arcsecond astrometry in space", Astr. J. 125, 1580-1597 (2003). -** -** Called: -** eraPdp scalar product of two p-vectors -** eraPxp vector product of two p-vectors -** -** Copyright (C) 2013-2016, NumFOCUS Foundation. -** Derived, with permission, from the SOFA library. See notes at end of file. -*/ -{ - int i; - double qpe[3], qdqpe, w, eq[3], peq[3]; - - -/* q . (q + e). */ - for (i = 0; i < 3; i++) { - qpe[i] = q[i] + e[i]; - } - qdqpe = eraPdp(q, qpe); - -/* 2 x G x bm / ( em x c^2 x ( q . (q + e) ) ). */ - w = bm * ERFA_SRS / em / ERFA_GMAX(qdqpe,dlim); - -/* p x (e x q). */ - eraPxp(e, q, eq); - eraPxp(p, eq, peq); - -/* Apply the deflection. */ - for (i = 0; i < 3; i++) { - p1[i] = p[i] + w*peq[i]; - } - -/* Finished. */ - -} -/*---------------------------------------------------------------------- -** -** -** 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. -** -*/ |