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Diffstat (limited to 'ast/erfa/apcs.c')
| -rw-r--r-- | ast/erfa/apcs.c | 233 |
1 files changed, 0 insertions, 233 deletions
diff --git a/ast/erfa/apcs.c b/ast/erfa/apcs.c deleted file mode 100644 index 0a34f14..0000000 --- a/ast/erfa/apcs.c +++ /dev/null @@ -1,233 +0,0 @@ -#include "erfa.h" - -void eraApcs(double date1, double date2, double pv[2][3], - double ebpv[2][3], double ehp[3], - eraASTROM *astrom) -/* -** - - - - - - - - -** e r a A p c s -** - - - - - - - - -** -** For an observer whose geocentric position and velocity are known, -** prepare star-independent astrometry parameters for transformations -** between ICRS and GCRS. The Earth ephemeris is supplied by the -** caller. -** -** The parameters produced by this function are required in the space -** motion, parallax, light deflection and aberration parts of the -** astrometric transformation chain. -** -** Given: -** date1 double TDB as a 2-part... -** date2 double ...Julian Date (Note 1) -** pv double[2][3] observer's geocentric pos/vel (m, m/s) -** ebpv double[2][3] Earth barycentric PV (au, au/day) -** ehp double[3] Earth heliocentric P (au) -** -** Returned: -** astrom eraASTROM* star-independent astrometry parameters: -** pmt double PM time interval (SSB, Julian years) -** eb double[3] SSB to observer (vector, au) -** eh double[3] Sun to observer (unit vector) -** em double distance from Sun to observer (au) -** v double[3] barycentric observer velocity (vector, c) -** bm1 double sqrt(1-|v|^2): reciprocal of Lorenz factor -** bpn double[3][3] bias-precession-nutation matrix -** along double unchanged -** xpl double unchanged -** ypl double unchanged -** sphi double unchanged -** cphi double unchanged -** diurab double unchanged -** eral double unchanged -** refa double unchanged -** refb double unchanged -** -** Notes: -** -** 1) The TDB date date1+date2 is a Julian Date, apportioned in any -** convenient way between the two arguments. For example, -** JD(TDB)=2450123.7 could be expressed in any of these ways, among -** others: -** -** date1 date2 -** -** 2450123.7 0.0 (JD method) -** 2451545.0 -1421.3 (J2000 method) -** 2400000.5 50123.2 (MJD method) -** 2450123.5 0.2 (date & time method) -** -** The JD method is the most natural and convenient to use in cases -** where the loss of several decimal digits of resolution is -** acceptable. The J2000 method is best matched to the way the -** argument is handled internally and will deliver the optimum -** resolution. The MJD method and the date & time methods are both -** good compromises between resolution and convenience. For most -** applications of this function the choice will not be at all -** critical. -** -** TT can be used instead of TDB without any significant impact on -** accuracy. -** -** 2) All the vectors are with respect to BCRS axes. -** -** 3) Providing separate arguments for (i) the observer's geocentric -** position and velocity and (ii) the Earth ephemeris is done for -** convenience in the geocentric, terrestrial and Earth orbit cases. -** For deep space applications it maybe more convenient to specify -** zero geocentric position and velocity and to supply the -** observer's position and velocity information directly instead of -** with respect to the Earth. However, note the different units: -** m and m/s for the geocentric vectors, au and au/day for the -** heliocentric and barycentric vectors. -** -** 4) In cases where the caller does not wish to provide the Earth -** ephemeris, the function eraApcs13 can be used instead of the -** present function. This computes the Earth ephemeris using the -** ERFA function eraEpv00. -** -** 5) This is one of several functions that inserts into the astrom -** structure star-independent parameters needed for the chain of -** astrometric transformations ICRS <-> GCRS <-> CIRS <-> observed. -** -** The various functions support different classes of observer and -** portions of the transformation chain: -** -** functions observer transformation -** -** eraApcg eraApcg13 geocentric ICRS <-> GCRS -** eraApci eraApci13 terrestrial ICRS <-> CIRS -** eraApco eraApco13 terrestrial ICRS <-> observed -** eraApcs eraApcs13 space ICRS <-> GCRS -** eraAper eraAper13 terrestrial update Earth rotation -** eraApio eraApio13 terrestrial CIRS <-> observed -** -** Those with names ending in "13" use contemporary ERFA models to -** compute the various ephemerides. The others accept ephemerides -** supplied by the caller. -** -** The transformation from ICRS to GCRS covers space motion, -** parallax, light deflection, and aberration. From GCRS to CIRS -** comprises frame bias and precession-nutation. From CIRS to -** observed takes account of Earth rotation, polar motion, diurnal -** aberration and parallax (unless subsumed into the ICRS <-> GCRS -** transformation), and atmospheric refraction. -** -** 6) The context structure astrom produced by this function is used by -** eraAtciq* and eraAticq*. -** -** Called: -** eraCp copy p-vector -** eraPm modulus of p-vector -** eraPn decompose p-vector into modulus and direction -** eraIr initialize r-matrix to identity -** -** Copyright (C) 2013-2016, NumFOCUS Foundation. -** Derived, with permission, from the SOFA library. See notes at end of file. -*/ -{ -/* au/d to m/s */ - const double AUDMS = ERFA_DAU/ERFA_DAYSEC; - -/* Light time for 1 AU (day) */ - const double CR = ERFA_AULT/ERFA_DAYSEC; - - int i; - double dp, dv, pb[3], vb[3], ph[3], v2, w; - - -/* Time since reference epoch, years (for proper motion calculation). */ - astrom->pmt = ( (date1 - ERFA_DJ00) + date2 ) / ERFA_DJY; - -/* Adjust Earth ephemeris to observer. */ - for (i = 0; i < 3; i++) { - dp = pv[0][i] / ERFA_DAU; - dv = pv[1][i] / AUDMS; - pb[i] = ebpv[0][i] + dp; - vb[i] = ebpv[1][i] + dv; - ph[i] = ehp[i] + dp; - } - -/* Barycentric position of observer (au). */ - eraCp(pb, astrom->eb); - -/* Heliocentric direction and distance (unit vector and au). */ - eraPn(ph, &astrom->em, astrom->eh); - -/* Barycentric vel. in units of c, and reciprocal of Lorenz factor. */ - v2 = 0.0; - for (i = 0; i < 3; i++) { - w = vb[i] * CR; - astrom->v[i] = w; - v2 += w*w; - } - astrom->bm1 = sqrt(1.0 - v2); - -/* Reset the NPB matrix. */ - eraIr(astrom->bpn); - -/* 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. -** -*/ |