public static function Bi00(&$dpsibi, &$depsbi, &$dra) {
    /* The frame bias corrections in longitude and obliquity */
    $DPBIAS = -0.041775 * DAS2R;
    $DEBIAS = -0.0068192 * DAS2R;

    /* The ICRS RA of the J2000.0 equinox (Chapront et al., 2002) */
    $DRA0 = -0.0146 * DAS2R;

    /* Return the results (which are fixed). */
    $dpsibi = $DPBIAS;
    $depsbi = $DEBIAS;
    $dra    = $DRA0;

    return;
  }
public static function Bi00(&$dpsibi, &$depsbi, &$dra) {
    /* The frame bias corrections in longitude and obliquity */
    $DPBIAS = -0.041775 * DAS2R;
    $DEBIAS = -0.0068192 * DAS2R;

    /* The ICRS RA of the J2000.0 equinox (Chapront et al., 2002) */
    $DRA0 = -0.0146 * DAS2R;

    /* Return the results (which are fixed). */
    $dpsibi = $DPBIAS;
    $depsbi = $DEBIAS;
    $dra    = $DRA0;

    return;
  }
public static function Bi00 ( & $ dpsibi , & $ depsbi , & $ dra ) { /* The frame bias corrections in longitude and obliquity */ $ DPBIAS = - 0.041775 * DAS2R ; $ DEBIAS = - 0.0068192 * DAS2R ; /* The ICRS RA of the J2000.0 equinox (Chapront et al., 2002) */ $ DRA0 = - 0.0146 * DAS2R ; /* Return the results (which are fixed). */ $ dpsibi = $ DPBIAS ; $ depsbi = $ DEBIAS ; $ dra = $ DRA0 ; return ; }
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i a u B i 0 0
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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 2015-02-09

Copyright (C) 2015 IAU SOFA Board.  See notes at end.
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