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#include "sofa.h"
void iauPvtob(double elong, double phi, double hm,
double xp, double yp, double sp, double theta,
double pv[2][3])
/*
** - - - - - - - - -
** i a u P v t o b
** - - - - - - - - -
**
** Position and velocity of a terrestrial observing station.
**
** This function is part of the International Astronomical Union's
** SOFA (Standards of Fundamental Astronomy) software collection.
**
** Status: support function.
**
** Given:
** elong double longitude (radians, east +ve, Note 1)
** phi double latitude (geodetic, radians, Note 1)
** hm double height above ref. ellipsoid (geodetic, m)
** xp,yp double coordinates of the pole (radians, Note 2)
** sp double the TIO locator s' (radians, Note 2)
** theta double Earth rotation angle (radians, Note 3)
**
** Returned:
** pv double[2][3] position/velocity vector (m, m/s, CIRS)
**
** Notes:
**
** 1) The terrestrial coordinates are with respect to the WGS84
** reference ellipsoid.
**
** 2) xp and yp are the coordinates (in radians) of the Celestial
** Intermediate Pole with respect to the International Terrestrial
** Reference System (see IERS Conventions), measured along the
** meridians 0 and 90 deg west respectively. sp is the TIO locator
** s', in radians, which positions the Terrestrial Intermediate
** Origin on the equator. For many applications, xp, yp and
** (especially) sp can be set to zero.
**
** 3) If theta is Greenwich apparent sidereal time instead of Earth
** rotation angle, the result is with respect to the true equator
** and equinox of date, i.e. with the x-axis at the equinox rather
** than the celestial intermediate origin.
**
** 4) The velocity units are meters per UT1 second, not per SI second.
** This is unlikely to have any practical consequences in the modern
** era.
**
** 5) No validation is performed on the arguments. Error cases that
** could lead to arithmetic exceptions are trapped by the iauGd2gc
** function, and the result set to zeros.
**
** References:
**
** McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003),
** IERS Technical Note No. 32, BKG (2004)
**
** Urban, S. & Seidelmann, P. K. (eds), Explanatory Supplement to
** the Astronomical Almanac, 3rd ed., University Science Books
** (2013), Section 7.4.3.3.
**
** Called:
** iauGd2gc geodetic to geocentric transformation
** iauPom00 polar motion matrix
** iauTrxp product of transpose of r-matrix and p-vector
**
** This revision: 2013 October 9
**
** SOFA release 2020-07-21
**
** Copyright (C) 2020 IAU SOFA Board. See notes at end.
*/
{
/* Earth rotation rate in radians per UT1 second */
const double OM = 1.00273781191135448 * D2PI / DAYSEC;
double xyzm[3], rpm[3][3], xyz[3], x, y, z, s, c;
/* Geodetic to geocentric transformation (WGS84). */
(void) iauGd2gc(1, elong, phi, hm, xyzm);
/* Polar motion and TIO position. */
iauPom00(xp, yp, sp, rpm);
iauTrxp(rpm, xyzm, xyz);
x = xyz[0];
y = xyz[1];
z = xyz[2];
/* Functions of ERA. */
s = sin(theta);
c = cos(theta);
/* Position. */
pv[0][0] = c*x - s*y;
pv[0][1] = s*x + c*y;
pv[0][2] = z;
/* Velocity. */
pv[1][0] = OM * ( -s*x - c*y );
pv[1][1] = OM * ( c*x - s*y );
pv[1][2] = 0.0;
/* Finished. */
/*----------------------------------------------------------------------
**
** Copyright (C) 2020
** 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
**
**--------------------------------------------------------------------*/
}