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#include "sofa.h"
void iauBi00(double *dpsibi, double *depsbi, double *dra)
/*
** - - - - - - - -
** i a u B i 0 0
** - - - - - - - -
**
** Frame bias components of IAU 2000 precession-nutation models (part
** of MHB2000 with additions).
**
** This function is part of the International Astronomical Union's
** SOFA (Standards Of Fundamental Astronomy) software collection.
**
** Status: canonical model.
**
** 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.
**
** This revision: 2013 June 18
**
** SOFA release 2020-07-21
**
** Copyright (C) 2020 IAU SOFA Board. See notes at end.
*/
{
/* The frame bias corrections in longitude and obliquity */
const double DPBIAS = -0.041775 * DAS2R,
DEBIAS = -0.0068192 * DAS2R;
/* The ICRS RA of the J2000.0 equinox (Chapront et al., 2002) */
const double DRA0 = -0.0146 * DAS2R;
/* Return the results (which are fixed). */
*dpsibi = DPBIAS;
*depsbi = DEBIAS;
*dra = DRA0;
return;
/*----------------------------------------------------------------------
**
** Copyright (C) 2020
** Standards Of Fundamental Astronomy Board
** of the International Astronomical Union.
**
** =====================
** SOFA Software License
** =====================
**
** NOTICE TO USER:
**
** BY USING THIS SOFTWARE YOU ACCEPT THE FOLLOWING SIX TERMS AND
** CONDITIONS WHICH APPLY TO ITS USE.
**
** 1. The Software is owned by the IAU SOFA Board ("SOFA").
**
** 2. Permission is granted to anyone to use the SOFA software for any
** purpose, including commercial applications, free of charge and
** without payment of royalties, subject to the conditions and
** restrictions listed below.
**
** 3. You (the user) may copy and distribute SOFA source code to others,
** and use and adapt its code and algorithms in your own software,
** on a world-wide, royalty-free basis. That portion of your
** distribution that does not consist of intact and unchanged copies
** of SOFA source code files is a "derived work" that must comply
** with the following requirements:
**
** a) Your work shall be marked or carry a statement that it
** (i) uses routines and computations derived by you from
** software provided by SOFA under license to you; and
** (ii) does not itself constitute software provided by and/or
** endorsed by SOFA.
**
** b) The source code of your derived work must contain descriptions
** of how the derived work is based upon, contains and/or differs
** from the original SOFA software.
**
** c) The names of all routines in your derived work shall not
** include the prefix "iau" or "sofa" or trivial modifications
** thereof such as changes of case.
**
** d) The origin of the SOFA components of your derived work must
** not be misrepresented; you must not claim that you wrote the
** original software, nor file a patent application for SOFA
** software or algorithms embedded in the SOFA software.
**
** e) These requirements must be reproduced intact in any source
** distribution and shall apply to anyone to whom you have
** granted a further right to modify the source code of your
** derived work.
**
** Note that, as originally distributed, the SOFA software is
** intended to be a definitive implementation of the IAU standards,
** and consequently third-party modifications are discouraged. All
** variations, no matter how minor, must be explicitly marked as
** such, as explained above.
**
** 4. You shall not cause the SOFA software to be brought into
** disrepute, either by misuse, or use for inappropriate tasks, or
** by inappropriate modification.
**
** 5. The SOFA software is provided "as is" and SOFA makes no warranty
** as to its use or performance. SOFA does not and cannot warrant
** the performance or results which the user may obtain by using the
** SOFA software. SOFA makes no warranties, express or implied, as
** to non-infringement of third party rights, merchantability, or
** fitness for any particular purpose. In no event will SOFA be
** liable to the user for any consequential, incidental, or special
** damages, including any lost profits or lost savings, even if a
** SOFA representative has been advised of such damages, or for any
** claim by any third party.
**
** 6. The provision of any version of the SOFA software under the terms
** and conditions specified herein does not imply that future
** versions will also be made available under the same terms and
** conditions.
*
** In any published work or commercial product which uses the SOFA
** software directly, acknowledgement (see www.iausofa.org) is
** appreciated.
**
** Correspondence concerning SOFA software should be addressed as
** follows:
**
** By email: sofa@ukho.gov.uk
** By post: IAU SOFA Center
** HM Nautical Almanac Office
** UK Hydrographic Office
** Admiralty Way, Taunton
** Somerset, TA1 2DN
** United Kingdom
**
**--------------------------------------------------------------------*/
}