text: #include "sofa.h"
  
  double iauEe00b(double date1, double date2)
  /*
  **  - - - - - - - - -
  **   i a u E e 0 0 b
  **  - - - - - - - - -
  **
  **  Equation of the equinoxes, compatible with IAU 2000 resolutions but
  **  using the truncated nutation model IAU 2000B.
  **
  **  This function is part of the International Astronomical Union's
  **  SOFA (Standards Of Fundamental Astronomy) software collection.
  **
  **  Status:  support function.
  **
  **  Given:
  **     date1,date2  double    TT as a 2-part Julian Date (Note 1)
  **
  **  Returned (function value):
  **                  double    equation of the equinoxes (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 result, which is in radians, operates in the following sense:
  **
  **        Greenwich apparent ST = GMST + equation of the equinoxes
  **
  **  3) The result is compatible with the IAU 2000 resolutions except
  **     that accuracy has been compromised for the sake of speed.  For
  **     further details, see McCarthy & Luzum (2001), IERS Conventions
  **     2003 and Capitaine et al. (2003).
  **
  **  Called:
  **     iauPr00      IAU 2000 precession adjustments
  **     iauObl80     mean obliquity, IAU 1980
  **     iauNut00b    nutation, IAU 2000B
  **     iauEe00      equation of the equinoxes, IAU 2000
  **
  **  References:
  **
  **     Capitaine, N., Wallace, P.T. and McCarthy, D.D., "Expressions to
  **     implement the IAU 2000 definition of UT1", Astronomy &
  **     Astrophysics, 406, 1135-1149 (2003)
  **
  **     McCarthy, D.D. & Luzum, B.J., "An abridged model of the
  **     precession-nutation of the celestial pole", Celestial Mechanics &
  **     Dynamical Astronomy, 85, 37-49 (2003)
  **
  **     McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003),
  **     IERS Technical Note No. 32, BKG (2004)
  **
  **  This revision:  2008 May 18
  **
  **  SOFA release 2013-12-02
  **
  **  Copyright (C) 2013 IAU SOFA Board.  See notes at end.
  */
  {
     double dpsipr, depspr, epsa, dpsi, deps, ee;
  
  
  /* IAU 2000 precession-rate adjustments. */
     iauPr00(date1, date2, &dpsipr, &depspr);
  
  /* Mean obliquity, consistent with IAU 2000 precession-nutation. */
     epsa = iauObl80(date1, date2) + depspr;
  
  /* Nutation in longitude. */
     iauNut00b(date1, date2, &dpsi, &deps);
  
  /* Equation of the equinoxes. */
     ee = iauEe00(date1, date2, epsa, dpsi);
  
     return ee;
  
  /*----------------------------------------------------------------------
  **
  **  Copyright (C) 2013
  **  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
  **
  **--------------------------------------------------------------------*/
  }
  