diff options
Diffstat (limited to 'ast/erfa/xys00a.c')
| -rw-r--r-- | ast/erfa/xys00a.c | 142 |
1 files changed, 0 insertions, 142 deletions
diff --git a/ast/erfa/xys00a.c b/ast/erfa/xys00a.c deleted file mode 100644 index 41a0723..0000000 --- a/ast/erfa/xys00a.c +++ /dev/null @@ -1,142 +0,0 @@ -#include "erfa.h" - -void eraXys00a(double date1, double date2, - double *x, double *y, double *s) -/* -** - - - - - - - - - - -** e r a X y s 0 0 a -** - - - - - - - - - - -** -** For a given TT date, compute the X,Y coordinates of the Celestial -** Intermediate Pole and the CIO locator s, using the IAU 2000A -** precession-nutation model. -** -** Given: -** date1,date2 double TT as a 2-part Julian Date (Note 1) -** -** Returned: -** x,y double Celestial Intermediate Pole (Note 2) -** s double the CIO locator s (Note 2) -** -** Notes: -** -** 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) The Celestial Intermediate Pole coordinates are the x,y -** components of the unit vector in the Geocentric Celestial -** Reference System. -** -** 3) The CIO locator s (in radians) positions the Celestial -** Intermediate Origin on the equator of the CIP. -** -** 4) A faster, but slightly less accurate result (about 1 mas for -** X,Y), can be obtained by using instead the eraXys00b function. -** -** Called: -** eraPnm00a classical NPB matrix, IAU 2000A -** eraBpn2xy extract CIP X,Y coordinates from NPB matrix -** eraS00 the CIO locator s, given X,Y, IAU 2000A -** -** Reference: -** -** McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003), -** IERS Technical Note No. 32, BKG (2004) -** -** Copyright (C) 2013-2016, NumFOCUS Foundation. -** Derived, with permission, from the SOFA library. See notes at end of file. -*/ -{ - double rbpn[3][3]; - - -/* Form the bias-precession-nutation matrix, IAU 2000A. */ - eraPnm00a(date1, date2, rbpn); - -/* Extract X,Y. */ - eraBpn2xy(rbpn, x, y); - -/* Obtain s. */ - *s = eraS00(date1, date2, *x, *y); - - 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. -** -*/ |