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use ;
/// Catalog −> CIRS
///
/// Transform ICRS star data, epoch J2000.0, to CIRS.
///
/// This function is part of the International Astronomical Union's
/// SOFA (Standards of Fundamental Astronomy) software collection.
///
/// Status: support function.
///
/// Given:
/// ```
/// rc double ICRS right ascension at J2000.0 (radians, Note 1)
/// dc double ICRS declination at J2000.0 (radians, Note 1)
/// pr double RA proper motion (radians/year, Note 2)
/// pd double Dec proper motion (radians/year)
/// px double parallax (arcsec)
/// rv double radial velocity (km/s, +ve if receding)
/// date1 double TDB as a 2-part...
/// date2 double ...Julian Date (Note 3)
/// ```
/// Return:
/// ```
/// ri,di double* CIRS geocentric RA,Dec (radians)
/// eo double* equation of the origins (ERA-GST, radians, Note 5)
/// ```
/// Notes:
///
/// 1) Star data for an epoch other than J2000.0 (for example from the
/// Hipparcos catalog, which has an epoch of J1991.25) will require a
/// preliminary call to iauPmsafe before use.
///
/// 2) The proper motion in RA is dRA/dt rather than cos(Dec)*dRA/dt.
///
/// 3) The TDB date date1+date2 is a Julian Date, apportioned in any
/// convenient way between the two arguments. For example,
/// JD(TDB)=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. For most
/// applications of this function the choice will not be at all
/// critical.
///
/// TT can be used instead of TDB without any significant impact on
/// accuracy.
///
/// 4) The available accuracy is better than 1 milliarcsecond, limited
/// mainly by the precession-nutation model that is used, namely
/// IAU 2000A/2006. Very close to solar system bodies, additional
/// errors of up to several milliarcseconds can occur because of
/// unmodeled light deflection; however, the Sun's contribution is
/// taken into account, to first order. The accuracy limitations of
/// the SOFA function iauEpv00 (used to compute Earth position and
/// velocity) can contribute aberration errors of up to
/// 5 microarcseconds. Light deflection at the Sun's limb is
/// uncertain at the 0.4 mas level.
///
/// 5) Should the transformation to (equinox based) apparent place be
/// required rather than (CIO based) intermediate place, subtract the
/// equation of the origins from the returned right ascension:
/// RA = RI - EO. (The iauAnp function can then be applied, as
/// required, to keep the result in the conventional 0-2pi range.)
///
/// Called:
/// ```
/// iauApci13 astrometry parameters, ICRS-CIRS, 2013
/// iauAtciq quick ICRS to CIRS
/// ```