sofam.h

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#ifndef SOFAMHDEF
#define SOFAMHDEF

/*
**  - - - - - - - -
**   s o f a m . h
**  - - - - - - - -
**
**  Macros used by SOFA library.
**
**  This file is part of the International Astronomical Union's
**  SOFA (Standards Of Fundamental Astronomy) software collection.
**
**  Please note that the constants defined below are to be used only in
**  the context of the SOFA software, and have no other official IAU
**  status.  In addition, self consistency is not guaranteed.
**
**  This revision:   2017 March 16
**
**  SOFA release 2017-04-20
**
**  Copyright (C) 2017 IAU SOFA Board.  See notes at end.
*/

/* Star-independent astrometry parameters */
typedef struct {
    double pmt;       /* PM time interval (SSB, Julian years) */
    double eb[3];     /* SSB to observer (vector, au) */
    double eh[3];     /* Sun to observer (unit vector) */
    double em;        /* distance from Sun to observer (au) */
    double v[3];      /* barycentric observer velocity (vector, c) */
    double bm1;       /* sqrt(1-|v|^2): reciprocal of Lorenz factor */
    double bpn[3][3]; /* bias-precession-nutation matrix */
    double along;     /* longitude + s' + dERA(DUT) (radians) */
    double phi;       /* geodetic latitude (radians) */
    double xpl;       /* polar motion xp wrt local meridian (radians) */
    double ypl;       /* polar motion yp wrt local meridian (radians) */
    double sphi;      /* sine of geodetic latitude */
    double cphi;      /* cosine of geodetic latitude */
    double diurab;    /* magnitude of diurnal aberration vector */
    double eral;      /* "local" Earth rotation angle (radians) */
    double refa;      /* refraction constant A (radians) */
    double refb;      /* refraction constant B (radians) */
} iauASTROM;
/* (Vectors eb, eh, em and v are all with respect to BCRS axes.) */

/* Body parameters for light deflection */
typedef struct {
    double bm;       /* mass of the body (solar masses) */
    double dl;       /* deflection limiter (radians^2/2) */
    double pv[2][3]; /* barycentric PV of the body (au, au/day) */
} iauLDBODY;

/* Pi */
#define DPI ( 3.141592653589793238462643 )

/* 2Pi */
#define D2PI ( 6.283185307179586476925287 )

/* Radians to degrees */
#define DR2D ( 57.29577951308232087679815 )

/* Degrees to radians */
#define DD2R ( 1.745329251994329576923691e-2 )

/* Radians to arcseconds */
#define DR2AS ( 206264.8062470963551564734 )

/* Arcseconds to radians */
#define DAS2R ( 4.848136811095359935899141e-6 )

/* Seconds of time to radians */
#define DS2R ( 7.272205216643039903848712e-5 )

/* Arcseconds in a full circle */
#define TURNAS ( 1296000.0 )

/* Milliarcseconds to radians */
#define DMAS2R ( DAS2R / 1e3 )

/* Length of tropical year B1900 (days) */
#define DTY ( 365.242198781 )

/* Seconds per day. */
#define DAYSEC ( 86400.0 )

/* Days per Julian year */
#define DJY ( 365.25 )

/* Days per Julian century */
#define DJC ( 36525.0 )

/* Days per Julian millennium */
#define DJM ( 365250.0 )

/* Reference epoch (J2000.0), Julian Date */
#define DJ00 ( 2451545.0 )

/* Julian Date of Modified Julian Date zero */
#define DJM0 ( 2400000.5 )

/* Reference epoch (J2000.0), Modified Julian Date */
#define DJM00 ( 51544.5 )

/* 1977 Jan 1.0 as MJD */
#define DJM77 ( 43144.0 )

/* TT minus TAI (s) */
#define TTMTAI ( 32.184 )

/* Astronomical unit (m, IAU 2012) */
#define DAU ( 149597870.7e3 )

/* Speed of light (m/s) */
#define CMPS 299792458.0

/* Light time for 1 au (s) */
#define AULT ( DAU / CMPS )

/* Speed of light (au per day) */
#define DC ( DAYSEC / AULT )

/* L_G = 1 - d(TT)/d(TCG) */
#define ELG ( 6.969290134e-10 )

/* L_B = 1 - d(TDB)/d(TCB), and TDB (s) at TAI 1977/1/1.0 */
#define ELB ( 1.550519768e-8 )
#define TDB0 ( -6.55e-5 )

/* Schwarzschild radius of the Sun (au) */
/* = 2 * 1.32712440041e20 / (2.99792458e8)^2 / 1.49597870700e11 */
#define SRS 1.97412574336e-8

/* dint(A) - truncate to nearest whole number towards zero (double) */
#define dint( A ) ( ( A ) < 0.0 ? ceil( A ) : floor( A ) )

/* dnint(A) - round to nearest whole number (double) */
#define dnint( A ) ( ( A ) < 0.0 ? ceil( (A)-0.5 ) : floor( ( A ) + 0.5 ) )

/* dsign(A,B) - magnitude of A with sign of B (double) */
#define dsign( A, B ) ( ( B ) < 0.0 ? -fabs( A ) : fabs( A ) )

/* max(A,B) - larger (most +ve) of two numbers (generic) */
#define gmax( A, B ) ( ( ( A ) > ( B ) ) ? ( A ) : ( B ) )

/* min(A,B) - smaller (least +ve) of two numbers (generic) */
#define gmin( A, B ) ( ( ( A ) < ( B ) ) ? ( A ) : ( B ) )

/* Reference ellipsoids */
#define WGS84 1
#define GRS80 2
#define WGS72 3

#endif

/*----------------------------------------------------------------------
**
**  Copyright (C) 2017
**  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
**
**--------------------------------------------------------------------*/