void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[]) {
double TT1, TT2, dX, dY, *xVec;
size_t numRow, numVec;
mxArray *retMat;
double *retData;
double GCRS2CIRS[3][3];
if(nrhs<3||nrhs>4){
mexErrMsgTxt("Wrong number of inputs");
}
if(nlhs>2) {
mexErrMsgTxt("Wrong number of outputs.");
}
checkRealDoubleArray(prhs[0]);
numRow = mxGetM(prhs[0]);
numVec = mxGetN(prhs[0]);
if(!(numRow==3||numRow==6)) {
mexErrMsgTxt("The input vector has a bad dimensionality.");
}
xVec=(double*)mxGetData(prhs[0]);
TT1=getDoubleFromMatlab(prhs[1]);
TT2=getDoubleFromMatlab(prhs[2]);
//If some values from the function getEOP will be needed.
if(nrhs<4||mxGetM(prhs[3])==0) {
mxArray *retVals[2];
double *dXdY;
mxArray *JulUTCMATLAB[2];
double JulUTC[2];
int retVal;
//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(2,retVals,2,JulUTCMATLAB,"getEOP");
mxDestroyArray(JulUTCMATLAB[0]);
mxDestroyArray(JulUTCMATLAB[1]);
//%We do not need the polar motion coordinates.
mxDestroyArray(retVals[0]);
checkRealDoubleArray(retVals[1]);
if(mxGetM(retVals[1])!=2||mxGetN(retVals[1])!=1) {
mxDestroyArray(retVals[1]);
mexErrMsgTxt("Error using the getEOP function.");
return;
}
dXdY=(double*)mxGetData(retVals[1]);
dX=dXdY[0];
dY=dXdY[1];
//Free the returned arrays.
mxDestroyArray(retVals[1]);
} else {//Get the celestial pole offsets
size_t dim1, dim2;
checkRealDoubleArray(prhs[4]);
dim1 = mxGetM(prhs[4]);
dim2 = mxGetN(prhs[4]);
if((dim1==2&&dim2==1)||(dim1==1&&dim2==2)) {
double *dXdY=(double*)mxGetData(prhs[4]);
dX=dXdY[0];
dY=dXdY[1];
} else {
mexErrMsgTxt("The celestial pole offsets have the wrong dimensionality.");
return;
}
}
{
double x, y, s;
double omega;
//Get the X,Y coordinates of the Celestial Intermediate Pole (CIP) and
//the Celestial Intermediate Origin (CIO) locator s, using the IAU 2006
//precession and IAU 2000A nutation models.
iauXys06a(TT1, TT2, &x, &y, &s);
//Add the CIP offsets.
x += dX;
y += dY;
//Get the GCRS-to-CIRS matrix
iauC2ixys(x, y, s, GCRS2CIRS);
}
//Allocate space for the return vectors.
retMat=mxCreateDoubleMatrix(numRow,numVec,mxREAL);
retData=(double*)mxGetData(retMat);
{
size_t curVec;
for(curVec=0;curVec<numVec;curVec++) {
//Multiply the position vector with the rotation matrix.
iauRxp(GCRS2CIRS, xVec+numRow*curVec, retData+numRow*curVec);
//If a velocity vector was given.
if(numRow>3) {
double *velGCRS=xVec+numRow*curVec+3;//Velocity in GCRS
double *retDataVel=retData+numRow*curVec+3;
//Convert velocity from GCRS to CIRS.
iauRxp(GCRS2CIRS, velGCRS, retDataVel);
}
}
}
plhs[0]=retMat;
//If the rotation matrix is desired on the output.
if(nlhs>1) {
double *elPtr;
size_t i,j;
plhs[1]=mxCreateDoubleMatrix(3,3,mxREAL);
elPtr=(double*)mxGetData(plhs[1]);
for (i=0;i<3;i++) {
for(j=0;j<3;j++) {
elPtr[i+3*j]=GCRS2CIRS[i][j];
}
}
}
}
void iauApco(double date1, double date2,
double ebpv[2][3], double ehp[3],
double x, double y, double s, double theta,
double elong, double phi, double hm,
double xp, double yp, double sp,
double refa, double refb,
iauASTROM *astrom)
/*
** - - - - - - - -
** i a u A p c o
** - - - - - - - -
**
** For a terrestrial observer, prepare star-independent astrometry
** parameters for transformations between ICRS and observed
** coordinates. The caller supplies the Earth ephemeris, the Earth
** rotation 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:
** date1 double TDB as a 2-part...
** date2 double ...Julian Date (Note 1)
** ebpv double[2][3] Earth barycentric PV (au, au/day, Note 2)
** ehp double[3] Earth heliocentric P (au, Note 2)
** x,y double CIP X,Y (components of unit vector)
** s double the CIO locator s (radians)
** theta double Earth rotation angle (radians)
** elong double longitude (radians, east +ve, Note 3)
** phi double latitude (geodetic, radians, Note 3)
** hm double height above ellipsoid (m, geodetic, Note 3)
** xp,yp double polar motion coordinates (radians, Note 4)
** sp double the TIO locator s' (radians, Note 4)
** refa double refraction constant A (radians, Note 5)
** refb double refraction constant B (radians, Note 5)
**
** Returned:
** astrom iauASTROM* star-independent astrometry parameters:
** pmt double PM time interval (SSB, Julian years)
** eb double[3] SSB to observer (vector, au)
** eh double[3] Sun to observer (unit vector)
** em double distance from Sun to observer (au)
** v double[3] barycentric observer velocity (vector, c)
** bm1 double sqrt(1-|v|^2): reciprocal of Lorenz factor
** bpn double[3][3] bias-precession-nutation matrix
** along double longitude + s' (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) The TDB date date1+date2 is a Julian Date, apportioned in any
** convenient way between the two arguments. For example,
** JD(TDB)=2450123.7 could be expressed in any of these ways, among
** others:
**
** date1 date2
**
** 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 method is best matched to the way the
** argument is handled internally and will deliver the optimum
** resolution. The MJD method and the date & time methods are both
** good compromises between resolution and convenience. For most
** applications of this function the choice will not be at all
** critical.
**
** TT can be used instead of TDB without any significant impact on
** accuracy.
**
** 2) The vectors eb, eh, and all the astrom vectors, are with respect
** to BCRS axes.
**
** 3) The geographical coordinates are with respect to the WGS84
** reference ellipsoid. TAKE CARE WITH THE LONGITUDE SIGN
** CONVENTION: the longitude required by the present function is
** right-handed, i.e. east-positive, in accordance with geographical
** convention.
**
** 4) 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.
**
** Internally, the polar motion is stored in a form rotated onto the
** local meridian.
**
** 5) 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.
**
** 6) 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.
**
** 7) In cases where the caller does not wish to provide the Earth
** Ephemeris, the Earth rotation information and refraction
** constants, the function iauApco13 can be used instead of the
** present function. This starts from UTC and weather readings etc.
** and computes suitable values using other SOFA functions.
**
** 8) 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.
**
** 9) The context structure astrom produced by this function is used by
** iauAtioq, iauAtoiq, iauAtciq* and iauAticq*.
**
** Called:
** iauAper astrometry parameters: update ERA
** iauC2ixys celestial-to-intermediate matrix, given X,Y and s
** iauPvtob position/velocity of terrestrial station
** iauTrxpv product of transpose of r-matrix and pv-vector
** iauApcs astrometry parameters, ICRS-GCRS, space observer
** iauCr copy r-matrix
**
** This revision: 2013 October 9
**
** SOFA release 2013-12-02
**
** Copyright (C) 2013 IAU SOFA Board. See notes at end.
*/
{
double sl, cl, r[3][3], pvc[2][3], pv[2][3];
/* Longitude with adjustment for TIO locator s'. */
astrom->along = elong + sp;
/* Polar motion, rotated onto the local meridian. */
sl = sin(astrom->along);
cl = cos(astrom->along);
astrom->xpl = xp*cl - yp*sl;
astrom->ypl = xp*sl + yp*cl;
/* Functions of latitude. */
astrom->sphi = sin(phi);
astrom->cphi = cos(phi);
/* Refraction constants. */
astrom->refa = refa;
astrom->refb = refb;
/* Local Earth rotation angle. */
iauAper(theta, astrom);
/* Disable the (redundant) diurnal aberration step. */
astrom->diurab = 0.0;
/* CIO based BPN matrix. */
iauC2ixys(x, y, s, r);
/* Observer's geocentric position and velocity (m, m/s, CIRS). */
iauPvtob(elong, phi, hm, xp, yp, sp, theta, pvc);
/* Rotate into GCRS. */
iauTrxpv(r, pvc, pv);
/* ICRS <-> GCRS parameters. */
iauApcs(date1, date2, pv, ebpv, ehp, astrom);
/* Store the CIO based BPN matrix. */
iauCr(r, astrom->bpn );
/* Finished. */
/*----------------------------------------------------------------------
**
** Copyright (C) 2013
** 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 iauApci(double date1, double date2,
double ebpv[2][3], double ehp[3],
double x, double y, double s,
iauASTROM *astrom)
/*
** - - - - - - - -
** i a u A p c i
** - - - - - - - -
**
** For a terrestrial observer, prepare star-independent astrometry
** parameters for transformations between ICRS and geocentric CIRS
** coordinates. The Earth ephemeris and CIP/CIO are supplied by the
** caller.
**
** The parameters produced by this function are required in the
** parallax, light deflection, aberration, and bias-precession-nutation
** parts of the astrometric transformation chain.
**
** This function is part of the International Astronomical Union's
** SOFA (Standards of Fundamental Astronomy) software collection.
**
** Status: support function.
**
** Given:
** date1 double TDB as a 2-part...
** date2 double ...Julian Date (Note 1)
** ebpv double[2][3] Earth barycentric position/velocity (au, au/day)
** ehp double[3] Earth heliocentric position (au)
** x,y double CIP X,Y (components of unit vector)
** s double the CIO locator s (radians)
**
** Returned:
** astrom iauASTROM* star-independent astrometry parameters:
** pmt double PM time interval (SSB, Julian years)
** eb double[3] SSB to observer (vector, au)
** eh double[3] Sun to observer (unit vector)
** em double distance from Sun to observer (au)
** v double[3] barycentric observer velocity (vector, c)
** bm1 double sqrt(1-|v|^2): reciprocal of Lorenz factor
** bpn double[3][3] bias-precession-nutation matrix
** along double unchanged
** xpl double unchanged
** ypl double unchanged
** sphi double unchanged
** cphi double unchanged
** diurab double unchanged
** eral double unchanged
** refa double unchanged
** refb double unchanged
**
** Notes:
**
** 1) The TDB date date1+date2 is a Julian Date, apportioned in any
** convenient way between the two arguments. For example,
** JD(TDB)=2450123.7 could be expressed in any of these ways, among
** others:
**
** date1 date2
**
** 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 method is best matched to the way the
** argument is handled internally and will deliver the optimum
** resolution. The MJD method and the date & time methods are both
** good compromises between resolution and convenience. For most
** applications of this function the choice will not be at all
** critical.
**
** TT can be used instead of TDB without any significant impact on
** accuracy.
**
** 2) All the vectors are with respect to BCRS axes.
**
** 3) In cases where the caller does not wish to provide the Earth
** ephemeris and CIP/CIO, the function iauApci13 can be used instead
** of the present function. This computes the required quantities
** using other SOFA functions.
**
** 4) 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.
**
** 5) The context structure astrom produced by this function is used by
** iauAtciq* and iauAticq*.
**
** Called:
** iauApcg astrometry parameters, ICRS-GCRS, geocenter
** iauC2ixys celestial-to-intermediate matrix, given X,Y and s
**
** This revision: 2013 September 25
**
** SOFA release 2015-02-09
**
** Copyright (C) 2015 IAU SOFA Board. See notes at end.
*/
{
/* Star-independent astrometry parameters for geocenter. */
iauApcg(date1, date2, ebpv, ehp, astrom);
/* CIO based BPN matrix. */
iauC2ixys(x, y, s, astrom->bpn);
/* Finished. */
/*----------------------------------------------------------------------
**
** 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 mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[]) {
size_t numRow,numVec;
mxArray *retMat;
double *xVec, *retData;
double TT1, TT2, UT11, UT12;
//The if-statements below should properly initialize all of the EOP.
//The following initializations to zero are to suppress warnings when
//compiling with -Wconditional-uninitialized.
double dX=0;
double dY=0;
double deltaT=0;
double LOD=0;
double GCRS2TIRS[3][3];
//Polar motion matrix. ITRS=POM*TIRS. We will just be setting it to the
//identity matrix as polar motion is not taken into account when going
//to the TIRS.
double rident[3][3]={{1,0,0},{0,1,0},{0,0,1}};
double Omega[3];//The rotation vector in the TIRS
if(nrhs<3||nrhs>6){
mexErrMsgTxt("Wrong number of inputs");
}
if(nlhs>2) {
mexErrMsgTxt("Wrong number of outputs.");
}
checkRealDoubleArray(prhs[0]);
numRow = mxGetM(prhs[0]);
numVec = mxGetN(prhs[0]);
if(!(numRow==3||numRow==6)) {
mexErrMsgTxt("The input vector has a bad dimensionality.");
}
xVec=(double*)mxGetData(prhs[0]);
TT1=getDoubleFromMatlab(prhs[1]);
TT2=getDoubleFromMatlab(prhs[2]);
//If some values from the function getEOP will be needed
if(nrhs<=5||mxIsEmpty(prhs[3])||mxIsEmpty(prhs[4])||mxIsEmpty(prhs[5])) {
mxArray *retVals[5];
double *dXdY;
mxArray *JulUTCMATLAB[2];
double JulUTC[2];
int retVal;
//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(5,retVals,2,JulUTCMATLAB,"getEOP");
mxDestroyArray(JulUTCMATLAB[0]);
mxDestroyArray(JulUTCMATLAB[1]);
//%We do not need the polar motion coordinates.
mxDestroyArray(retVals[0]);
checkRealDoubleArray(retVals[1]);
if(mxGetM(retVals[1])!=2||mxGetN(retVals[1])!=1) {
mxDestroyArray(retVals[1]);
mxDestroyArray(retVals[2]);
mxDestroyArray(retVals[3]);
mxDestroyArray(retVals[4]);
mexErrMsgTxt("Error using the getEOP function.");
return;
}
dXdY=(double*)mxGetData(retVals[1]);
dX=dXdY[0];
dY=dXdY[1];
//This is TT-UT1
deltaT=getDoubleFromMatlab(retVals[3]);
LOD=getDoubleFromMatlab(retVals[4]);
//Free the returned arrays.
mxDestroyArray(retVals[1]);
mxDestroyArray(retVals[2]);
mxDestroyArray(retVals[3]);
mxDestroyArray(retVals[4]);
}
//If deltaT=TT-UT1 is given
if(nrhs>3&&!mxIsEmpty(prhs[3])) {
deltaT=getDoubleFromMatlab(prhs[3]);
}
//Obtain UT1 from terestrial time and deltaT.
iauTtut1(TT1, TT2, deltaT, &UT11, &UT12);
//Get celestial pole offsets, if given.
if(nrhs>4&&!mxIsEmpty(prhs[4])) {
size_t dim1, dim2;
checkRealDoubleArray(prhs[4]);
dim1 = mxGetM(prhs[4]);
dim2 = mxGetN(prhs[4]);
if((dim1==2&&dim2==1)||(dim1==1&&dim2==2)) {
double *dXdY=(double*)mxGetData(prhs[4]);
dX=dXdY[0];
dY=dXdY[1];
} else {
mexErrMsgTxt("The celestial pole offsets have the wrong dimensionality.");
return;
}
}
//If LOD is given
if(nrhs>5&&mxIsEmpty(prhs[5])) {
LOD=getDoubleFromMatlab(prhs[5]);
}
//Compute the rotation matrix for going from GCRS to ITRS as well as
//the instantaneous vector angular momentum due to the Earth's rotation
//in TIRS coordinates.
{
double x, y, s, era;
double rc2i[3][3];
double omega;
//Get the X,Y coordinates of the Celestial Intermediate Pole (CIP) and
//the Celestial Intermediate Origin (CIO) locator s, using the IAU 2006
//precession and IAU 2000A nutation models.
iauXys06a(TT1, TT2, &x, &y, &s);
//Add the CIP offsets.
x += dX;
y += dY;
//Get the GCRS-to-CIRS matrix
iauC2ixys(x, y, s, rc2i);
//Find the Earth rotation angle for the given UT1 time.
era = iauEra00(UT11, UT12);
//Set the polar motion matrix to the identity matrix so that the
//conversion stops at the TIRS instead of the ITRS.
//Combine the GCRS-to-CIRS matrix, the Earth rotation angle, and use
//the identity matrix instead of the polar motion matrix to get a
//to get the rotation matrix to go from GCRS to TIRS.
iauC2tcio(rc2i, era, rident,GCRS2TIRS);
//Next, to be able to transform the velocity, the rotation of the Earth
//has to be taken into account.
//The angular velocity vector of the Earth in the TIRS in radians.
omega=getScalarMatlabClassConst("Constants","IERSMeanEarthRotationRate");
//Adjust for LOD
omega=omega*(1-LOD/86400.0);//86400.0 is the number of seconds in a TT
//day.
Omega[0]=0;
Omega[1]=0;
Omega[2]=omega;
}
//Allocate space for the return vectors.
retMat=mxCreateDoubleMatrix(numRow,numVec,mxREAL);
retData=(double*)mxGetData(retMat);
{
size_t curVec;
for(curVec=0;curVec<numVec;curVec++) {
//Multiply the position vector with the rotation matrix.
iauRxp(GCRS2TIRS, xVec+numRow*curVec, retData+numRow*curVec);
//If a velocity vector was given.
if(numRow>3) {
double *posGCRS=xVec+numRow*curVec;
double posTIRS[3];
double *velGCRS=xVec+numRow*curVec+3;//Velocity in GCRS
double velTIRS[3];
double *retDataVel=retData+numRow*curVec+3;
double rotVel[3];
//If a velocity was provided with the position, first
//convert to TIRS coordinates, then account for the
//rotation of the Earth.
//Convert velocity from GCRS to TIRS.
iauRxp(GCRS2TIRS, velGCRS, velTIRS);
//Convert position from GCRS to TIRS
iauRxp(GCRS2TIRS, posGCRS, posTIRS);
//Evaluate the cross product for the angular velocity due
//to the Earth's rotation.
iauPxp(Omega, posTIRS, rotVel);
//Subtract out the instantaneous velocity due to rotation.
iauPmp(velTIRS, rotVel, retDataVel);
}
}
}
plhs[0]=retMat;
//If the rotation matrix is desired on the output.
if(nlhs>1) {
double *elPtr;
size_t i,j;
plhs[1]=mxCreateDoubleMatrix(3,3,mxREAL);
elPtr=(double*)mxGetData(plhs[1]);
for (i=0;i<3;i++) {
for(j=0;j<3;j++) {
elPtr[i+3*j]=GCRS2TIRS[i][j];
}
}
}
}
void iauC2ixy(double date1, double date2, double x, double y,
double rc2i[3][3])
/*
** - - - - - - - - -
** i a u C 2 i x y
** - - - - - - - - -
**
** Form the celestial to intermediate-frame-of-date matrix for a given
** date when the CIP X,Y coordinates are known. IAU 2000.
**
** This function is part of the International Astronomical Union's
** SOFA (Standards Of Fundamental Astronomy) software collection.
**
** Status: support function.
**
** Given:
** date1,date2 double TT as a 2-part Julian Date (Note 1)
** x,y double Celestial Intermediate Pole (Note 2)
**
** Returned:
** rc2i double[3][3] celestial-to-intermediate matrix (Note 3)
**
** Notes:
**
** 1) The TT date date1+date2 is a Julian Date, apportioned in any
** convenient way between the two arguments. For example,
** JD(TT)=2450123.7 could be expressed in any of these ways,
** among others:
**
** date1 date2
**
** 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 method is best matched to the way
** the argument is handled internally and will deliver the
** optimum resolution. The MJD method and the date & time methods
** are both good compromises between resolution and convenience.
**
** 2) The Celestial Intermediate Pole coordinates are the x,y components
** of the unit vector in the Geocentric Celestial Reference System.
**
** 3) The matrix rc2i is the first stage in the transformation from
** celestial to terrestrial coordinates:
**
** [TRS] = RPOM * R_3(ERA) * rc2i * [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), ERA is the Earth
** Rotation Angle and RPOM is the polar motion matrix.
**
** 4) Although its name does not include "00", This function is in fact
** specific to the IAU 2000 models.
**
** Called:
** iauC2ixys celestial-to-intermediate matrix, given X,Y and s
** iauS00 the CIO locator s, given X,Y, IAU 2000A
**
** Reference:
**
** McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003),
** IERS Technical Note No. 32, BKG (2004)
**
** This revision: 2013 June 18
**
** SOFA release 2016-05-03
**
** Copyright (C) 2016 IAU SOFA Board. See notes at end.
*/
{
/* Compute s and then the matrix. */
iauC2ixys(x, y, iauS00(date1, date2, x, y), rc2i);
return;
/*----------------------------------------------------------------------
**
** Copyright (C) 2016
** 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
**
**--------------------------------------------------------------------*/
}
