//! Function to calculate GMST according to requested IAU conventions double calculateGreenwichMeanSiderealTime( const double terrestrialTime, const double universalTime1, const double referenceJulianDay, const basic_astrodynamics::IAUConventions iauConvention ) { // Declare GMST variable double gmst = TUDAT_NAN; // Check for IAU convention and retrieve requested GMST switch( iauConvention ) { case basic_astrodynamics::iau_2000_a: gmst = iauGmst00( referenceJulianDay, universalTime1 / physical_constants::JULIAN_DAY, referenceJulianDay, terrestrialTime / physical_constants::JULIAN_DAY ); break; case basic_astrodynamics::iau_2000_b: gmst = iauGmst00( referenceJulianDay, universalTime1 / physical_constants::JULIAN_DAY, referenceJulianDay, terrestrialTime / physical_constants::JULIAN_DAY ); break; case basic_astrodynamics::iau_2006: gmst = iauGmst06( referenceJulianDay, universalTime1 / physical_constants::JULIAN_DAY, referenceJulianDay, terrestrialTime / physical_constants::JULIAN_DAY ); break; default: throw std::runtime_error( "Warning, iau convention for GMST calculation not recongnized" ); } return gmst; }
double iauGst00a(double uta, double utb, double tta, double ttb) /* ** - - - - - - - - - - ** i a u G s t 0 0 a ** - - - - - - - - - - ** ** Greenwich apparent sidereal time (consistent with IAU 2000 ** resolutions). ** ** This function is part of the International Astronomical Union's ** SOFA (Standards Of Fundamental Astronomy) software collection. ** ** Status: canonical model. ** ** Given: ** uta,utb double UT1 as a 2-part Julian Date (Notes 1,2) ** tta,ttb double TT as a 2-part Julian Date (Notes 1,2) ** ** Returned (function value): ** double Greenwich apparent sidereal time (radians) ** ** Notes: ** ** 1) The UT1 and TT dates uta+utb and tta+ttb respectively, are both ** Julian Dates, apportioned in any convenient way between the ** argument pairs. For example, JD=2450123.7 could be expressed in ** any of these ways, among others: ** ** Part A Part B ** ** 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 (in the case of UT; the TT is not at all critical ** in this respect). The J2000 and MJD methods are good compromises ** between resolution and convenience. For UT, the date & time ** method is best matched to the algorithm that is used by the Earth ** Rotation Angle function, called internally: maximum precision is ** delivered when the uta argument is for 0hrs UT1 on the day in ** question and the utb argument lies in the range 0 to 1, or vice ** versa. ** ** 2) Both UT1 and TT are required, UT1 to predict the Earth rotation ** and TT to predict the effects of precession-nutation. If UT1 is ** used for both purposes, errors of order 100 microarcseconds ** result. ** ** 3) This GAST is compatible with the IAU 2000 resolutions and must be ** used only in conjunction with other IAU 2000 compatible ** components such as precession-nutation. ** ** 4) The result is returned in the range 0 to 2pi. ** ** 5) The algorithm is from Capitaine et al. (2003) and IERS ** Conventions 2003. ** ** Called: ** iauGmst00 Greenwich mean sidereal time, IAU 2000 ** iauEe00a equation of the equinoxes, IAU 2000A ** iauAnp normalize angle into range 0 to 2pi ** ** References: ** ** Capitaine, N., Wallace, P.T. and McCarthy, D.D., "Expressions to ** implement the IAU 2000 definition of UT1", Astronomy & ** Astrophysics, 406, 1135-1149 (2003) ** ** 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. */ { double gmst00, ee00a, gst; gmst00 = iauGmst00(uta, utb, tta, ttb); ee00a = iauEe00a(tta, ttb); gst = iauAnp(gmst00 + ee00a); return gst; /*---------------------------------------------------------------------- ** ** Copyright (C) 2015 ** 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: [email protected] ** By post: IAU SOFA Center ** HM Nautical Almanac Office ** UK Hydrographic Office ** Admiralty Way, Taunton ** Somerset, TA1 2DN ** United Kingdom ** **--------------------------------------------------------------------*/ }
void iauC2tpe(double tta, double ttb, double uta, double utb, double dpsi, double deps, double xp, double yp, double rc2t[3][3]) /* ** - - - - - - - - - ** i a u C 2 t p e ** - - - - - - - - - ** ** Form the celestial to terrestrial matrix given the date, the UT1, ** the nutation and the polar motion. IAU 2000. ** ** This function is part of the International Astronomical Union's ** SOFA (Standards Of Fundamental Astronomy) software collection. ** ** Status: support function. ** ** Given: ** tta,ttb double TT as a 2-part Julian Date (Note 1) ** uta,utb double UT1 as a 2-part Julian Date (Note 1) ** dpsi,deps double nutation (Note 2) ** xp,yp double coordinates of the pole (radians, Note 3) ** ** Returned: ** rc2t double[3][3] celestial-to-terrestrial matrix (Note 4) ** ** Notes: ** ** 1) The TT and UT1 dates tta+ttb and uta+utb are Julian Dates, ** apportioned in any convenient way between the arguments uta and ** utb. For example, JD(UT1)=2450123.7 could be expressed in any of ** these ways, among others: ** ** uta utb ** ** 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 and MJD methods are good compromises ** between resolution and convenience. In the case of uta,utb, the ** date & time method is best matched to the Earth rotation angle ** algorithm used: maximum precision is delivered when the uta ** argument is for 0hrs UT1 on the day in question and the utb ** argument lies in the range 0 to 1, or vice versa. ** ** 2) The caller is responsible for providing the nutation components; ** they are in longitude and obliquity, in radians and are with ** respect to the equinox and ecliptic of date. For high-accuracy ** applications, free core nutation should be included as well as ** any other relevant corrections to the position of the CIP. ** ** 3) 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. ** ** 4) The matrix rc2t transforms from celestial to terrestrial ** coordinates: ** ** [TRS] = RPOM * R_3(GST) * RBPN * [CRS] ** ** = rc2t * [CRS] ** ** where [CRS] is a vector in the Geocentric Celestial Reference ** System and [TRS] is a vector in the International Terrestrial ** Reference System (see IERS Conventions 2003), RBPN is the ** bias-precession-nutation matrix, GST is the Greenwich (apparent) ** Sidereal Time and RPOM is the polar motion matrix. ** ** 5) Although its name does not include "00", This function is in fact ** specific to the IAU 2000 models. ** ** Called: ** iauPn00 bias/precession/nutation results, IAU 2000 ** iauGmst00 Greenwich mean sidereal time, IAU 2000 ** iauSp00 the TIO locator s', IERS 2000 ** iauEe00 equation of the equinoxes, IAU 2000 ** iauPom00 polar motion matrix ** iauC2teqx form equinox-based celestial-to-terrestrial matrix ** ** Reference: ** ** McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003), ** IERS Technical Note No. 32, BKG (2004) ** ** This revision: 2013 June 18 ** ** SOFA release 2017-04-20 ** ** Copyright (C) 2017 IAU SOFA Board. See notes at end. */ { double epsa, rb[3][3], rp[3][3], rbp[3][3], rn[3][3], rbpn[3][3], gmst, ee, sp, rpom[3][3]; /* Form the celestial-to-true matrix for this TT. */ iauPn00(tta, ttb, dpsi, deps, &epsa, rb, rp, rbp, rn, rbpn); /* Predict the Greenwich Mean Sidereal Time for this UT1 and TT. */ gmst = iauGmst00(uta, utb, tta, ttb); /* Predict the equation of the equinoxes given TT and nutation. */ ee = iauEe00(tta, ttb, epsa, dpsi); /* Estimate s'. */ sp = iauSp00(tta, ttb); /* Form the polar motion matrix. */ iauPom00(xp, yp, sp, rpom); /* Combine to form the celestial-to-terrestrial matrix. */ iauC2teqx(rbpn, gmst + ee, rpom, rc2t); return; /*---------------------------------------------------------------------- ** ** 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: [email protected] ** By post: IAU SOFA Center ** HM Nautical Almanac Office ** UK Hydrographic Office ** Admiralty Way, Taunton ** Somerset, TA1 2DN ** United Kingdom ** **--------------------------------------------------------------------*/ }
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[]) { double TT1, TT2, UT11,UT12, deltaT,GMST; int algToUse=2006; int retVal; if(nrhs<2||nrhs>4){ mexErrMsgTxt("Wrong number of inputs."); return; } if(nlhs>1){ mexErrMsgTxt("Wrong number of outputs."); return; } TT1=getDoubleFromMatlab(prhs[0]); TT2=getDoubleFromMatlab(prhs[1]); if(nrhs>2) { algToUse=getIntFromMatlab(prhs[2]); } if(nrhs>3) { deltaT=getDoubleFromMatlab(prhs[3]); } else { mxArray *retVals[4]; mxArray *JulUTCMATLAB[2]; double JulUTC[2]; //Get the time in UTC to look up the parameters by going to TAI and //then UTC. retVal=iauTttai(TT1, TT2, &JulUTC[0], &JulUTC[1]); if(retVal!=0) { mexErrMsgTxt("An error occurred computing TAI."); } retVal=iauTaiutc(JulUTC[0], JulUTC[1], &JulUTC[0], &JulUTC[1]); switch(retVal){ case 1: mexWarnMsgTxt("Dubious Date entered."); break; case -1: mexErrMsgTxt("Unacceptable date entered"); break; default: break; } JulUTCMATLAB[0]=doubleMat2Matlab(&JulUTC[0],1,1); JulUTCMATLAB[1]=doubleMat2Matlab(&JulUTC[1],1,1); //Get the Earth orientation parameters for the given date. mexCallMATLAB(4,retVals,2,JulUTCMATLAB,"getEOP"); //This is TT-UT1 deltaT=getDoubleFromMatlab(retVals[3]); //Free the returned arrays. mxDestroyArray(retVals[0]); mxDestroyArray(retVals[1]); mxDestroyArray(retVals[2]); mxDestroyArray(retVals[3]); mxDestroyArray(JulUTCMATLAB[0]); mxDestroyArray(JulUTCMATLAB[1]); } //Get UT1 retVal=iauTtut1(TT1, TT2, deltaT, &UT11, &UT12); if(retVal!=0) { mexErrMsgTxt("An error occurred computing UT1."); } //Get Greenwhich mean sidereal time in radians using the chosen //algorithm switch(algToUse) { case 1982: GMST=iauGmst82(UT11, UT12); break; case 2000: GMST=iauGmst00(UT11, UT12, TT1, TT2); break; case 2006: GMST=iauGmst06(UT11, UT12, TT1, TT2); break; default: mexErrMsgTxt("An invalid algorithm version was given."); } plhs[0]=doubleMat2Matlab(&GMST,1, 1); }