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#include "erfa.h"
void eraBi00(double *dpsibi, double *depsbi, double *dra)
/*
** - - - - - - - -
** e r a B i 0 0
** - - - - - - - -
**
** Frame bias components of IAU 2000 precession-nutation models (part
** of MHB2000 with additions).
**
** Returned:
** dpsibi,depsbi double longitude and obliquity corrections
** dra double the ICRS RA of the J2000.0 mean equinox
**
** Notes:
**
** 1) The frame bias corrections in longitude and obliquity (radians)
** are required in order to correct for the offset between the GCRS
** pole and the mean J2000.0 pole. They define, with respect to the
** GCRS frame, a J2000.0 mean pole that is consistent with the rest
** of the IAU 2000A precession-nutation model.
**
** 2) In addition to the displacement of the pole, the complete
** description of the frame bias requires also an offset in right
** ascension. This is not part of the IAU 2000A model, and is from
** Chapront et al. (2002). It is returned in radians.
**
** 3) This is a supplemented implementation of one aspect of the IAU
** 2000A nutation model, formally adopted by the IAU General
** Assembly in 2000, namely MHB2000 (Mathews et al. 2002).
**
** References:
**
** Chapront, J., Chapront-Touze, M. & Francou, G., Astron.
** Astrophys., 387, 700, 2002.
**
** Mathews, P.M., Herring, T.A., Buffet, B.A., "Modeling of nutation
** and precession New nutation series for nonrigid Earth and
** insights into the Earth's interior", J.Geophys.Res., 107, B4,
** 2002. The MHB2000 code itself was obtained on 9th September 2002
** from ftp://maia.usno.navy.mil/conv2000/chapter5/IAU2000A.
**
** Copyright (C) 2013-2016, NumFOCUS Foundation.
** Derived, with permission, from the SOFA library. See notes at end of file.
*/
{
/* The frame bias corrections in longitude and obliquity */
const double DPBIAS = -0.041775 * ERFA_DAS2R,
DEBIAS = -0.0068192 * ERFA_DAS2R;
/* The ICRS RA of the J2000.0 equinox (Chapront et al., 2002) */
const double DRA0 = -0.0146 * ERFA_DAS2R;
/* Return the results (which are fixed). */
*dpsibi = DPBIAS;
*depsbi = DEBIAS;
*dra = DRA0;
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.
**
*/
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