src/Marando/IAU/iauPom00.php
public static function Pom00($xp, $yp, $sp, array &$rpom) {
    /* Construct the matrix. */
    IAU::Ir($rpom);
    IAU::Rz($sp, $rpom);
    IAU::Ry(-$xp, $rpom);
    IAU::Rx(-$yp, $rpom);

    return;
  }
public static function Pom00($xp, $yp, $sp, array &$rpom) {
    /* Construct the matrix. */
    IAU::Ir($rpom);
    IAU::Rz($sp, $rpom);
    IAU::Ry(-$xp, $rpom);
    IAU::Rx(-$yp, $rpom);

    return;
  }
public static function Pom00 ( $ xp , $ yp , $ sp , array & $ rpom ) { /* Construct the matrix. */ IAU :: Ir ( $ rpom ) ; IAU :: Rz ( $ sp , $ rpom ) ; IAU :: Ry ( - $ xp , $ rpom ) ; IAU :: Rx ( - $ yp , $ rpom ) ; return ; }
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i a u P o m 0 0
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Form the matrix of polar motion for a given date, IAU 2000.

This function is part of the International Astronomical Union's
SOFA (Standards Of Fundamental Astronomy) software collection.

Status:  support function.

Given:
xp,yp    double    coordinates of the pole (radians, Note 1)
sp       double    the TIO locator s' (radians, Note 2)

Returned:
rpom     double[3][3]   polar-motion matrix (Note 3)

Notes:

1) The arguments xp and yp 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 to 0 and 90 deg west respectively.

2) The argument sp is the TIO locator s', in radians, which
positions the Terrestrial Intermediate Origin on the equator.  It
is obtained from polar motion observations by numerical
integration, and so is in essence unpredictable.  However, it is
dominated by a secular drift of about 47 microarcseconds per
century, and so can be taken into account by using s' = -47*t,
where t is centuries since J2000.0.  The function iauSp00
implements this approximation.

3) The matrix operates in the sense V(TRS) = rpom * V(CIP), meaning
that it is the final rotation when computing the pointing
direction to a celestial source.

Called:
iauIr        initialize r-matrix to identity
iauRz        rotate around Z-axis
iauRy        rotate around Y-axis
iauRx        rotate around X-axis

Reference:

McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003),
IERS Technical Note No. 32, BKG (2004)

This revision:  2013 June 18

SOFA release 2015-02-09

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