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use ;
use crateCMPS;
use crate;
/// Prepare for CIRS <−> observed, terrestrial, special
///
/// For a terrestrial observer, prepare star-independent astrometry
/// parameters for transformations between CIRS and observed
/// coordinates. The caller supplies the Earth orientation information
/// and the refraction constants as well as the site coordinates.
///
/// This function is part of the International Astronomical Union's
/// SOFA (Standards of Fundamental Astronomy) software collection.
///
/// Status: support function.
///
/// Given:
/// ```
/// sp double the TIO locator s' (radians, Note 1)
/// theta double Earth rotation angle (radians)
/// elong double longitude (radians, east +ve, Note 2)
/// phi double geodetic latitude (radians, Note 2)
/// hm double height above ellipsoid (m, geodetic Note 2)
/// xp,yp double polar motion coordinates (radians, Note 3)
/// refa double refraction constant A (radians, Note 4)
/// refb double refraction constant B (radians, Note 4)
/// ```
/// Returned:
/// ```
/// astrom iauASTROM* star-independent astrometry parameters:
/// pmt double unchanged
/// eb double[3] unchanged
/// eh double[3] unchanged
/// em double unchanged
/// v double[3] unchanged
/// bm1 double unchanged
/// bpn double[3][3] unchanged
/// along double adjusted longitude (radians)
/// xpl double polar motion xp wrt local meridian (radians)
/// ypl double polar motion yp wrt local meridian (radians)
/// sphi double sine of geodetic latitude
/// cphi double cosine of geodetic latitude
/// diurab double magnitude of diurnal aberration vector
/// eral double "local" Earth rotation angle (radians)
/// refa double refraction constant A (radians)
/// refb double refraction constant B (radians)
/// ```
/// Notes:
///
/// 1) sp, the TIO locator s', is a tiny quantity needed only by the
/// most precise applications. It can either be set to zero or
/// predicted using the SOFA function iauSp00.
///
/// 2) The geographical coordinates are with respect to the WGS84
/// reference ellipsoid. TAKE CARE WITH THE LONGITUDE SIGN: the
/// longitude required by the present function is east-positive
/// (i.e. right-handed), in accordance with geographical convention.
///
/// 3) The polar motion xp,yp can be obtained from IERS bulletins. The
/// values are the coordinates (in radians) of the Celestial
/// Intermediate Pole with respect to the International Terrestrial
/// Reference System (see IERS Conventions 2003), measured along the
/// meridians 0 and 90 deg west respectively. For many applications,
/// xp and yp can be set to zero.
///
/// Internally, the polar motion is stored in a form rotated onto the
/// local meridian.
///
/// 4) The refraction constants refa and refb are for use in a
/// dZ = A*tan(Z)+B*tan^3(Z) model, where Z is the observed
/// (i.e. refracted) zenith distance and dZ is the amount of
/// refraction.
///
/// 5) It is advisable to take great care with units, as even unlikely
/// values of the input parameters are accepted and processed in
/// accordance with the models used.
///
/// 6) In cases where the caller does not wish to provide the Earth
/// rotation information and refraction constants, the function
/// iauApio13 can be used instead of the present function. This
/// starts from UTC and weather readings etc. and computes suitable
/// values using other SOFA functions.
///
/// 7) This is one of several functions that inserts into the astrom
/// structure star-independent parameters needed for the chain of
/// astrometric transformations ICRS <-> GCRS <-> CIRS <-> observed.
///
/// The various functions support different classes of observer and
/// portions of the transformation chain:
/// ```
/// functions observer transformation
///
/// iauApcg iauApcg13 geocentric ICRS <-> GCRS
/// iauApci iauApci13 terrestrial ICRS <-> CIRS
/// iauApco iauApco13 terrestrial ICRS <-> observed
/// iauApcs iauApcs13 space ICRS <-> GCRS
/// iauAper iauAper13 terrestrial update Earth rotation
/// iauApio iauApio13 terrestrial CIRS <-> observed
/// ```
/// Those with names ending in "13" use contemporary SOFA models to
/// compute the various ephemerides. The others accept ephemerides
/// supplied by the caller.
///
/// The transformation from ICRS to GCRS covers space motion,
/// parallax, light deflection, and aberration. From GCRS to CIRS
/// comprises frame bias and precession-nutation. From CIRS to
/// observed takes account of Earth rotation, polar motion, diurnal
/// aberration and parallax (unless subsumed into the ICRS <-> GCRS
/// transformation), and atmospheric refraction.
///
/// 8) The context structure astrom produced by this function is used by
/// iauAtioq and iauAtoiq.
///
/// Called:
/// ```
/// iauIr initialize r-matrix to identity
/// iauRz rotate around Z-axis
/// iauRy rotate around Y-axis
/// iauRx rotate around X-axis
/// iauAnpm normalize angle into range +/- pi
/// iauPvtob position/velocity of terrestrial station
/// ```