void iauC2txy(double tta, double ttb, double uta, double utb,
double x, double y, double xp, double yp,
double rc2t[3][3])
/*
** - - - - - - - - -
** i a u C 2 t x y
** - - - - - - - - -
**
** Form the celestial to terrestrial matrix given the date, the UT1,
** the CIP coordinates and the polar motion. IAU 2000.
**
** 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)
** x,y double Celestial Intermediate Pole (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 o
** 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 Celestial Intermediate Pole coordinates are the x,y
** components of the unit vector in the Geocentric Celestial
** Reference System.
**
** 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(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.
**
** 5) Although its name does not include "00", This function is in fact
** specific to the IAU 2000 models.
**
** Called:
** iauC2ixy celestial-to-intermediate matrix, given X,Y
** iauEra00 Earth rotation angle, IAU 2000
** iauSp00 the TIO locator s', IERS 2000
** iauPom00 polar motion matrix
** iauC2tcio form CIO-based celestial-to-terrestrial matrix
**
** Reference:
**
** McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003),
** IERS Technical Note No. 32, BKG (2004)
**
** This revision: 2009 April 1
**
** Original version 2012-03-01
**
** Copyright (C) 2013 Naoki Arita. See notes at end.
*/
{
double rc2i[3][3], era, sp, rpom[3][3];
/* Form the celestial-to-intermediate matrix for this TT. */
iauC2ixy(tta, ttb, x, y, rc2i);
/* Predict the Earth rotation angle for this UT1. */
era = iauEra00(uta, utb);
/* Estimate s'. */
sp = iauSp00(tta, ttb);
/* Form the polar motion matrix. */
iauPom00(xp, yp, sp, rpom);
/* Combine to form the celestial-to-terrestrial matrix. */
iauC2tcio(rc2i, era, rpom, rc2t);
return;
/*----------------------------------------------------------------------
**
** Celes is a wrapper of the SOFA Library for Ruby.
**
** This file is redistributed and relicensed in accordance with
** the SOFA Software License (http://www.iausofa.org/tandc.html).
**
** The original library is available from IAU Standards of
** Fundamental Astronomy (http://www.iausofa.org/).
**
**
**
**
**
** Copyright (C) 2013, Naoki Arita
** All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
**
** 1 Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
**
** 2 Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
**
** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
** the International Astronomical Union nor the names of its
** contributors may be used to endorse or promote products derived
** from this software without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
** POSSIBILITY OF SUCH DAMAGE.
**
**--------------------------------------------------------------------*/
}
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];
}
}
}
}
double iauGmst06(double uta, double utb, double tta, double ttb)
/*
** - - - - - - - - - -
** i a u G m s t 0 6
** - - - - - - - - - -
**
** Greenwich mean sidereal time (consistent with IAU 2006 precession).
**
** 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 mean 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. If UT1 is used for
** both purposes, errors of order 100 microarcseconds result.
**
** 3) This GMST is compatible with the IAU 2006 precession and must not
** be used with other precession models.
**
** 4) The result is returned in the range 0 to 2pi.
**
** Called:
** iauEra00 Earth rotation angle, IAU 2000
** iauAnp normalize angle into range 0 to 2pi
**
** Reference:
**
** Capitaine, N., Wallace, P.T. & Chapront, J., 2005,
** Astron.Astrophys. 432, 355
**
** This revision: 2013 June 18
**
** SOFA release 2016-05-03
**
** Copyright (C) 2016 IAU SOFA Board. See notes at end.
*/
{
double t, gmst;
/* TT Julian centuries since J2000.0. */
t = ((tta - DJ00) + ttb) / DJC;
/* Greenwich mean sidereal time, IAU 2006. */
gmst = iauAnp(iauEra00(uta, utb) +
( 0.014506 +
( 4612.156534 +
( 1.3915817 +
( -0.00000044 +
( -0.000029956 +
( -0.0000000368 )
* t) * t) * t) * t) * t) * DAS2R);
return gmst;
/*----------------------------------------------------------------------
**
** 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
**
**--------------------------------------------------------------------*/
}
int iauApio13(double utc1, double utc2, double dut1,
double elong, double phi, double hm, double xp, double yp,
double phpa, double tc, double rh, double wl,
iauASTROM *astrom)
/*
** - - - - - - - - - -
** i a u A p i o 1 3
** - - - - - - - - - -
**
** For a terrestrial observer, prepare star-independent astrometry
** parameters for transformations between CIRS and observed
** coordinates. The caller supplies UTC, site coordinates, ambient air
** conditions and observing wavelength.
**
** This function is part of the International Astronomical Union's
** SOFA (Standards of Fundamental Astronomy) software collection.
**
** Status: support function.
**
** Given:
** utc1 double UTC as a 2-part...
** utc2 double ...quasi Julian Date (Notes 1,2)
** dut1 double UT1-UTC (seconds)
** elong double longitude (radians, east +ve, Note 3)
** phi double geodetic latitude (radians, Note 3)
** hm double height above ellipsoid (m, geodetic Notes 4,6)
** xp,yp double polar motion coordinates (radians, Note 5)
** phpa double pressure at the observer (hPa = mB, Note 6)
** tc double ambient temperature at the observer (deg C)
** rh double relative humidity at the observer (range 0-1)
** wl double wavelength (micrometers, Note 7)
**
** Returned:
** astrom iauASTROM* star-independent astrometry parameters:
** pmt double unchanged
** eb double[3] unchanged
** eh double[3] unchanged
** em double unchanged
** v double[3] unchanged
** bm1 double unchanged
** bpn double[3][3] unchanged
** 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)
**
** Returned (function value):
** int status: +1 = dubious year (Note 2)
** 0 = OK
** -1 = unacceptable date
**
** Notes:
**
** 1) utc1+utc2 is quasi Julian Date (see Note 2), apportioned in any
** convenient way between the two arguments, for example where utc1
** is the Julian Day Number and utc2 is the fraction of a day.
**
** However, JD cannot unambiguously represent UTC during a leap
** second unless special measures are taken. The convention in the
** present function is that the JD day represents UTC days whether
** the length is 86399, 86400 or 86401 SI seconds.
**
** Applications should use the function iauDtf2d to convert from
** calendar date and time of day into 2-part quasi Julian Date, as
** it implements the leap-second-ambiguity convention just
** described.
**
** 2) The warning status "dubious year" flags UTCs that predate the
** introduction of the time scale or that are too far in the future
** to be trusted. See iauDat for further details.
**
** 3) UT1-UTC is tabulated in IERS bulletins. It increases by exactly
** one second at the end of each positive UTC leap second,
** introduced in order to keep UT1-UTC within +/- 0.9s. n.b. This
** practice is under review, and in the future UT1-UTC may grow
** essentially without limit.
**
** 4) The geographical coordinates are with respect to the WGS84
** reference ellipsoid. TAKE CARE WITH THE LONGITUDE SIGN: the
** longitude required by the present function is east-positive
** (i.e. right-handed), in accordance with geographical convention.
**
** 5) The polar motion xp,yp can be obtained from IERS bulletins. The
** values 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 0 and 90 deg west respectively. For many applications,
** xp and yp can be set to zero.
**
** Internally, the polar motion is stored in a form rotated onto
** the local meridian.
**
** 6) If hm, the height above the ellipsoid of the observing station
** in meters, is not known but phpa, the pressure in hPa (=mB), is
** available, an adequate estimate of hm can be obtained from the
** expression
**
** hm = -29.3 * tsl * log ( phpa / 1013.25 );
**
** where tsl is the approximate sea-level air temperature in K
** (See Astrophysical Quantities, C.W.Allen, 3rd edition, section
** 52). Similarly, if the pressure phpa is not known, it can be
** estimated from the height of the observing station, hm, as
** follows:
**
** phpa = 1013.25 * exp ( -hm / ( 29.3 * tsl ) );
**
** Note, however, that the refraction is nearly proportional to the
** pressure and that an accurate phpa value is important for
** precise work.
**
** 7) The argument wl specifies the observing wavelength in
** micrometers. The transition from optical to radio is assumed to
** occur at 100 micrometers (about 3000 GHz).
**
** 8) 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.
**
** 9) In cases where the caller wishes to supply his own Earth
** rotation information and refraction constants, the function
** iauApc can be used instead of the present function.
**
** 10) 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.
**
** 11) The context structure astrom produced by this function is used
** by iauAtioq and iauAtoiq.
**
** Called:
** iauUtctai UTC to TAI
** iauTaitt TAI to TT
** iauUtcut1 UTC to UT1
** iauSp00 the TIO locator s', IERS 2000
** iauEra00 Earth rotation angle, IAU 2000
** iauRefco refraction constants for given ambient conditions
** iauApio astrometry parameters, CIRS-observed
**
** This revision: 2013 October 9
**
** SOFA release 2013-12-02
**
** Copyright (C) 2013 IAU SOFA Board. See notes at end.
*/
{
int j;
double tai1, tai2, tt1, tt2, ut11, ut12, sp, theta, refa, refb;
/* UTC to other time scales. */
j = iauUtctai(utc1, utc2, &tai1, &tai2);
if ( j < 0 ) return -1;
j = iauTaitt(tai1, tai2, &tt1, &tt2);
j = iauUtcut1(utc1, utc2, dut1, &ut11, &ut12);
if ( j < 0 ) return -1;
/* TIO locator s'. */
sp = iauSp00(tt1, tt2);
/* Earth rotation angle. */
theta = iauEra00(ut11, ut12);
/* Refraction constants A and B. */
iauRefco(phpa, tc, rh, wl, &refa, &refb);
/* CIRS <-> observed astrometry parameters. */
iauApio(sp, theta, elong, phi, hm, xp, yp, refa, refb, astrom);
/* Return any warning status. */
return j;
/* 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 iauC2t00b(double tta, double ttb, double uta, double utb,
double xp, double yp, double rc2t[3][3])
/*
** - - - - - - - - - -
** i a u C 2 t 0 0 b
** - - - - - - - - - -
**
** Form the celestial to terrestrial matrix given the date, the UT1 and
** the polar motion, using the IAU 2000B nutation model.
**
** 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)
** xp,yp double coordinates of the pole (radians, Note 2)
**
** Returned:
** rc2t double[3][3] celestial-to-terrestrial matrix (Note 3)
**
** 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 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.
**
** 3) The matrix rc2t transforms 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), RC2I is the
** celestial-to-intermediate matrix, ERA is the Earth rotation
** angle and RPOM is the polar motion matrix.
**
** 4) The present function is faster, but slightly less accurate (about
** 1 mas), than the iauC2t00a function.
**
** Called:
** iauC2i00b celestial-to-intermediate matrix, IAU 2000B
** iauEra00 Earth rotation angle, IAU 2000
** iauPom00 polar motion matrix
** iauC2tcio form CIO-based celestial-to-terrestrial matrix
**
** Reference:
**
** McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003),
** IERS Technical Note No. 32, BKG (2004)
**
** This revision: 2009 April 1
**
** SOFA release 2012-03-01
**
** Copyright (C) 2012 IAU SOFA Board. See notes at end.
*/
{
double rc2i[3][3], era, rpom[3][3];
/* Form the celestial-to-intermediate matrix for this TT (IAU 2000B). */
iauC2i00b(tta, ttb, rc2i);
/* Predict the Earth rotation angle for this UT1. */
era = iauEra00(uta, utb);
/* Form the polar motion matrix (neglecting s'). */
iauPom00(xp, yp, 0.0, rpom);
/* Combine to form the celestial-to-terrestrial matrix. */
iauC2tcio(rc2i, era, rpom, rc2t);
return;
/*----------------------------------------------------------------------
**
** Copyright (C) 2012
** 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 iauAper13(double ut11, double ut12, iauASTROM *astrom)
/*
** - - - - - - - - - -
** i a u A p e r 1 3
** - - - - - - - - - -
**
** In the star-independent astrometry parameters, update only the
** Earth rotation angle. The caller provides UT1, (n.b. not UTC).
**
** This function is part of the International Astronomical Union's
** SOFA (Standards of Fundamental Astronomy) software collection.
**
** Status: support function.
**
** Given:
** ut11 double UT1 as a 2-part...
** ut12 double ...Julian Date (Note 1)
** astrom iauASTROM* star-independent astrometry parameters:
** pmt double not used
** eb double[3] not used
** eh double[3] not used
** em double not used
** v double[3] not used
** bm1 double not used
** bpn double[3][3] not used
** along double longitude + s' (radians)
** xpl double not used
** ypl double not used
** sphi double not used
** cphi double not used
** diurab double not used
** eral double not used
** refa double not used
** refb double not used
**
** Returned:
** astrom iauASTROM* star-independent astrometry parameters:
** pmt double unchanged
** eb double[3] unchanged
** eh double[3] unchanged
** em double unchanged
** v double[3] unchanged
** bm1 double unchanged
** bpn double[3][3] unchanged
** along double unchanged
** xpl double unchanged
** ypl double unchanged
** sphi double unchanged
** cphi double unchanged
** diurab double unchanged
** eral double "local" Earth rotation angle (radians)
** refa double unchanged
** refb double unchanged
**
** Notes:
**
** 1) The UT1 date (n.b. not UTC) ut11+ut12 is a Julian Date,
** apportioned in any convenient way between the arguments ut11 and
** ut12. For example, JD(UT1)=2450123.7 could be expressed in any
** of these ways, among others:
**
** ut11 ut12
**
** 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. The date & time method is
** best matched to the algorithm used: maximum precision is
** delivered when the ut11 argument is for 0hrs UT1 on the day in
** question and the ut12 argument lies in the range 0 to 1, or vice
** versa.
**
** 2) If the caller wishes to provide the Earth rotation angle itself,
** the function iauAper can be used instead. One use of this
** technique is to substitute Greenwich apparent sidereal time and
** thereby to support equinox based transformations directly.
**
** 3) 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.
**
** Called:
** iauAper astrometry parameters: update ERA
** iauEra00 Earth rotation angle, IAU 2000
**
** This revision: 2013 September 25
**
** SOFA release 2015-02-09
**
** Copyright (C) 2015 IAU SOFA Board. See notes at end.
*/
{
iauAper(iauEra00(ut11,ut12), astrom);
/* 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[]) {
double TT1,TT2,*xVec;
double deltaT=0;
double LOD=0;
size_t numRow,numVec;
double CIRS2TIRS[3][3];
double TIRS2CIRS[3][3];
double Omega[3];//The rotation vector in the TIRS
mxArray *retMat;
double *retData;
if(nrhs<3||nrhs>5){
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||mxIsEmpty(prhs[3])||mxIsEmpty(prhs[4])) {
mxArray *retVals[5];
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]);
//We do not need the celestial pole offsets.
mxDestroyArray(retVals[1]);
//This is TT-UT1
deltaT=getDoubleFromMatlab(retVals[3]);
LOD=getDoubleFromMatlab(retVals[4]);
//Free the returned arrays.
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]);
}
//If LOD is given
if(nrhs>4&&!mxIsEmpty(prhs[4])) {
LOD=getDoubleFromMatlab(prhs[4]);
}
//Compute the rotation matrix for going from CIRS to TIRS as well as
//the instantaneous vector angular momentum due to the Earth's rotation
//in GCRS coordinates.
{
double UT11, UT12;
double era, omega;
//Obtain UT1 from terestrial time and deltaT.
iauTtut1(TT1, TT2, deltaT, &UT11, &UT12);
//Find the Earth rotation angle for the given UT1 time.
era = iauEra00(UT11, UT12);
//Construct the rotation matrix.
CIRS2TIRS[0][0]=1;
CIRS2TIRS[0][1]=0;
CIRS2TIRS[0][2]=0;
CIRS2TIRS[1][0]=0;
CIRS2TIRS[1][1]=1;
CIRS2TIRS[1][2]=0;
CIRS2TIRS[2][0]=0;
CIRS2TIRS[2][1]=0;
CIRS2TIRS[2][2]=1;
iauRz(era, CIRS2TIRS);
//To go from the TIRS to the GCRS, we need to use the inverse rotation
//matrix, which is just the transpose of the rotation matrix.
iauTr(CIRS2TIRS, TIRS2CIRS);
//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(TIRS2CIRS, xVec+numRow*curVec, retData+numRow*curVec);
//If a velocity vector was given.
if(numRow>3) {
double *posTIRS=xVec+numRow*curVec;
double *velTIRS=xVec+numRow*curVec+3;//Velocity in GCRS
double *retDataVel=retData+numRow*curVec+3;
double rotVel[3];
//Evaluate the cross product for the angular velocity due
//to the Earth's rotation.
iauPxp(Omega, posTIRS, rotVel);
//Add the instantaneous velocity due to rotation.
iauPpp(velTIRS, rotVel, retDataVel);
//Rotate from TIRS to GCRS
iauRxp(TIRS2CIRS, retDataVel, retDataVel);
}
}
}
plhs[0]=retMat;
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]=TIRS2CIRS[i][j];
}
}
}
}
//! Function to calculate ERA (earth rotation angle)
double calculateEarthRotationAngle( const double ut1, const double julianDaysEpochShift )
{
return iauEra00( julianDaysEpochShift, ut1 / physical_constants::JULIAN_DAY );
}