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Diffstat (limited to 'ast/erfa/eqec06.c')
| -rw-r--r-- | ast/erfa/eqec06.c | 142 |
1 files changed, 0 insertions, 142 deletions
diff --git a/ast/erfa/eqec06.c b/ast/erfa/eqec06.c deleted file mode 100644 index 6a667c9..0000000 --- a/ast/erfa/eqec06.c +++ /dev/null @@ -1,142 +0,0 @@ -#include "erfa.h" - -void eraEqec06(double date1, double date2, double dr, double dd, - double *dl, double *db) -/* -** - - - - - - - - - - -** e r a E q e c 0 6 -** - - - - - - - - - - -** -** Transformation from ICRS equatorial coordinates to ecliptic -** coordinates (mean equinox and ecliptic of date) using IAU 2006 -** precession model. -** -** Given: -** date1,date2 double TT as a 2-part Julian date (Note 1) -** dr,dd double ICRS right ascension and declination (radians) -** -** Returned: -** dl,db double ecliptic longitude and latitude (radians) -** -** 1) The TT date date1+date2 is a Julian Date, apportioned in any -** convenient way between the two arguments. For example, -** JD(TT)=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. -** -** 2) No assumptions are made about whether the coordinates represent -** starlight and embody astrometric effects such as parallax or -** aberration. -** -** 3) The transformation is approximately that from mean J2000.0 right -** ascension and declination to ecliptic longitude and latitude -** (mean equinox and ecliptic of date), with only frame bias (always -** less than 25 mas) to disturb this classical picture. -** -** Called: -** eraS2c spherical coordinates to unit vector -** eraEcm06 J2000.0 to ecliptic rotation matrix, IAU 2006 -** eraRxp product of r-matrix and p-vector -** eraC2s unit vector to spherical coordinates -** eraAnp normalize angle into range 0 to 2pi -** eraAnpm normalize angle into range +/- pi -** -** Copyright (C) 2013-2016, NumFOCUS Foundation. -** Derived, with permission, from the SOFA library. See notes at end of file. -*/ -{ - double rm[3][3], v1[3], v2[3], a, b; - - -/* Spherical to Cartesian. */ - eraS2c(dr, dd, v1); - -/* Rotation matrix, ICRS equatorial to ecliptic. */ - eraEcm06(date1, date2, rm); - -/* The transformation from ICRS to ecliptic. */ - eraRxp(rm, v1, v2); - -/* Cartesian to spherical. */ - eraC2s(v2, &a, &b); - -/* Express in conventional ranges. */ - *dl = eraAnp(a); - *db = eraAnpm(b); - -} -/*---------------------------------------------------------------------- -** -** -** 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. -** -*/ |