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Diffstat (limited to 'ast/erfa/starpm.c')
| -rw-r--r-- | ast/erfa/starpm.c | 214 |
1 files changed, 0 insertions, 214 deletions
diff --git a/ast/erfa/starpm.c b/ast/erfa/starpm.c deleted file mode 100644 index 69b7708..0000000 --- a/ast/erfa/starpm.c +++ /dev/null @@ -1,214 +0,0 @@ -#include "erfa.h" - -int eraStarpm(double ra1, double dec1, - double pmr1, double pmd1, double px1, double rv1, - double ep1a, double ep1b, double ep2a, double ep2b, - double *ra2, double *dec2, - double *pmr2, double *pmd2, double *px2, double *rv2) -/* -** - - - - - - - - - - -** e r a S t a r p m -** - - - - - - - - - - -** -** Star proper motion: update star catalog data for space motion. -** -** Given: -** ra1 double right ascension (radians), before -** dec1 double declination (radians), before -** pmr1 double RA proper motion (radians/year), before -** pmd1 double Dec proper motion (radians/year), before -** px1 double parallax (arcseconds), before -** rv1 double radial velocity (km/s, +ve = receding), before -** ep1a double "before" epoch, part A (Note 1) -** ep1b double "before" epoch, part B (Note 1) -** ep2a double "after" epoch, part A (Note 1) -** ep2b double "after" epoch, part B (Note 1) -** -** Returned: -** ra2 double right ascension (radians), after -** dec2 double declination (radians), after -** pmr2 double RA proper motion (radians/year), after -** pmd2 double Dec proper motion (radians/year), after -** px2 double parallax (arcseconds), after -** rv2 double radial velocity (km/s, +ve = receding), after -** -** Returned (function value): -** int status: -** -1 = system error (should not occur) -** 0 = no warnings or errors -** 1 = distance overridden (Note 6) -** 2 = excessive velocity (Note 7) -** 4 = solution didn't converge (Note 8) -** else = binary logical OR of the above warnings -** -** Notes: -** -** 1) The starting and ending TDB dates ep1a+ep1b and ep2a+ep2b are -** Julian Dates, apportioned in any convenient way between the two -** parts (A and B). For example, JD(TDB)=2450123.7 could be -** expressed in any of these ways, among others: -** -** epna epnb -** -** 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. -** -** 2) In accordance with normal star-catalog conventions, the object's -** right ascension and declination are freed from the effects of -** secular aberration. The frame, which is aligned to the catalog -** equator and equinox, is Lorentzian and centered on the SSB. -** -** The proper motions are the rate of change of the right ascension -** and declination at the catalog epoch and are in radians per TDB -** Julian year. -** -** The parallax and radial velocity are in the same frame. -** -** 3) Care is needed with units. The star coordinates are in radians -** and the proper motions in radians per Julian year, but the -** parallax is in arcseconds. -** -** 4) The RA proper motion is in terms of coordinate angle, not true -** angle. If the catalog uses arcseconds for both RA and Dec proper -** motions, the RA proper motion will need to be divided by cos(Dec) -** before use. -** -** 5) Straight-line motion at constant speed, in the inertial frame, -** is assumed. -** -** 6) An extremely small (or zero or negative) parallax is interpreted -** to mean that the object is on the "celestial sphere", the radius -** of which is an arbitrary (large) value (see the eraStarpv -** function for the value used). When the distance is overridden in -** this way, the status, initially zero, has 1 added to it. -** -** 7) If the space velocity is a significant fraction of c (see the -** constant VMAX in the function eraStarpv), it is arbitrarily set -** to zero. When this action occurs, 2 is added to the status. -** -** 8) The relativistic adjustment carried out in the eraStarpv function -** involves an iterative calculation. If the process fails to -** converge within a set number of iterations, 4 is added to the -** status. -** -** Called: -** eraStarpv star catalog data to space motion pv-vector -** eraPvu update a pv-vector -** eraPdp scalar product of two p-vectors -** eraPvstar space motion pv-vector to star catalog data -** -** Copyright (C) 2013-2016, NumFOCUS Foundation. -** Derived, with permission, from the SOFA library. See notes at end of file. -*/ -{ - double pv1[2][3], tl1, dt, pv[2][3], r2, rdv, v2, c2mv2, tl2, - pv2[2][3]; - int j1, j2, j; - - -/* RA,Dec etc. at the "before" epoch to space motion pv-vector. */ - j1 = eraStarpv(ra1, dec1, pmr1, pmd1, px1, rv1, pv1); - -/* Light time when observed (days). */ - tl1 = eraPm(pv1[0]) / ERFA_DC; - -/* Time interval, "before" to "after" (days). */ - dt = (ep2a - ep1a) + (ep2b - ep1b); - -/* Move star along track from the "before" observed position to the */ -/* "after" geometric position. */ - eraPvu(dt + tl1, pv1, pv); - -/* From this geometric position, deduce the observed light time (days) */ -/* at the "after" epoch (with theoretically unneccessary error check). */ - r2 = eraPdp(pv[0], pv[0]); - rdv = eraPdp(pv[0], pv[1]); - v2 = eraPdp(pv[1], pv[1]); - c2mv2 = ERFA_DC*ERFA_DC - v2; - if (c2mv2 <= 0) return -1; - tl2 = (-rdv + sqrt(rdv*rdv + c2mv2*r2)) / c2mv2; - -/* Move the position along track from the observed place at the */ -/* "before" epoch to the observed place at the "after" epoch. */ - eraPvu(dt + (tl1 - tl2), pv1, pv2); - -/* Space motion pv-vector to RA,Dec etc. at the "after" epoch. */ - j2 = eraPvstar(pv2, ra2, dec2, pmr2, pmd2, px2, rv2); - -/* Final status. */ - j = (j2 == 0) ? j1 : -1; - - return j; - -} -/*---------------------------------------------------------------------- -** -** -** 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. -** -*/ |