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#include "erfa.h"
#include "erfam.h"
void eraFk5hip(double r5h[3][3], double s5h[3])
/*
** - - - - - - - - - -
** e r a F k 5 h i p
** - - - - - - - - - -
**
** FK5 to Hipparcos rotation and spin.
**
** Returned:
** r5h double[3][3] r-matrix: FK5 rotation wrt Hipparcos (Note 2)
** s5h double[3] r-vector: FK5 spin wrt Hipparcos (Note 3)
**
** Notes:
**
** 1) This function models the FK5 to Hipparcos transformation as a
** pure rotation and spin; zonal errors in the FK5 catalogue are
** not taken into account.
**
** 2) The r-matrix r5h operates in the sense:
**
** P_Hipparcos = r5h x P_FK5
**
** where P_FK5 is a p-vector in the FK5 frame, and P_Hipparcos is
** the equivalent Hipparcos p-vector.
**
** 3) The r-vector s5h represents the time derivative of the FK5 to
** Hipparcos rotation. The units are radians per year (Julian,
** TDB).
**
** Called:
** eraRv2m r-vector to r-matrix
**
** Reference:
**
** F.Mignard & M.Froeschle, Astron.Astrophys., 354, 732-739 (2000).
**
** This revision: 2021 May 11
**
** Copyright (C) 2013-2021, NumFOCUS Foundation.
** Derived, with permission, from the SOFA library. See notes at end of file.
*/
{
double v[3];
/* FK5 wrt Hipparcos orientation and spin (radians, radians/year) */
double epx, epy, epz;
double omx, omy, omz;
epx = -19.9e-3 * ERFA_DAS2R;
epy = -9.1e-3 * ERFA_DAS2R;
epz = 22.9e-3 * ERFA_DAS2R;
omx = -0.30e-3 * ERFA_DAS2R;
omy = 0.60e-3 * ERFA_DAS2R;
omz = 0.70e-3 * ERFA_DAS2R;
/* FK5 to Hipparcos orientation expressed as an r-vector. */
v[0] = epx;
v[1] = epy;
v[2] = epz;
/* Re-express as an r-matrix. */
eraRv2m(v, r5h);
/* Hipparcos wrt FK5 spin expressed as an r-vector. */
s5h[0] = omx;
s5h[1] = omy;
s5h[2] = omz;
/* Finished. */
}
/*----------------------------------------------------------------------
**
**
** Copyright (C) 2013-2021, 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.
**
*/