/** Destroy a DetectorStateSeries (and set it to NULL) */
void
LALDestroyDetectorStateSeries (LALStatus *status, /**< pointer to LALStatus structure */
DetectorStateSeries **detStates ) /**< pointer to vector to be destroyed */
{
INITSTATUS(status);
ASSERT ( detStates, status, DETECTORSTATES_ENULL, DETECTORSTATES_MSGENULL);
XLALDestroyDetectorStateSeries ( (*detStates) );
(*detStates) = NULL;
RETURN (status);
} /* LALDestroyDetectorStateSeries() */
/**
* Helper function to get rid of a multi-IFO DetectorStateSeries
* Note, this is "NULL-robust" in the sense that it will not crash
* on NULL-entries anywhere in this struct, so it can be used
* for failure-cleanup even on incomplete structs.
*/
void
XLALDestroyMultiDetectorStateSeries ( MultiDetectorStateSeries *mdetStates )
{
UINT4 X, numDet;
if ( !mdetStates )
return;
numDet = mdetStates->length;
if ( mdetStates->data )
{
for ( X=0; X < numDet ; X ++ )
XLALDestroyDetectorStateSeries ( mdetStates->data[X] );
LALFree ( mdetStates->data );
}
LALFree ( mdetStates );
return;
} /* XLALDestroyMultiDetectorStateSeries() */
/**
* Get the 'detector state' (ie detector-tensor, position, velocity, etc) for the given
* vector of timestamps, shifted by a common time-shift \a tOffset.
*
* This function just calls XLALBarycenterEarth() and XLALBarycenter() for the
* given vector of timestamps (shifted by tOffset) and returns the positions,
* velocities and LMSTs of the detector, stored in a DetectorStateSeries.
* There is also an entry containing the EarthState at each timestamp, which
* can be used as input for subsequent calls to XLALBarycenter().
*
* \a tOffset allows one to easily use the midpoints of SFT-timestamps, for example.
*
*/
DetectorStateSeries *
XLALGetDetectorStates ( const LIGOTimeGPSVector *timestamps, /**< array of GPS timestamps t_i */
const LALDetector *detector, /**< detector info */
const EphemerisData *edat, /**< ephemeris file data */
REAL8 tOffset /**< compute detector states at timestamps SHIFTED by tOffset */
)
{
/* check input consistency */
if ( !timestamps || !detector || !edat ) {
XLALPrintError ("%s: invalid NULL input, timestamps=%p, detector=%p, edat=%p\n", __func__, timestamps, detector, edat );
XLAL_ERROR_NULL ( XLAL_EINVAL );
}
/* prepare return vector */
UINT4 numSteps = timestamps->length;
DetectorStateSeries *ret = NULL;
if ( ( ret = XLALCreateDetectorStateSeries ( numSteps )) == NULL ) {
XLALPrintError ("%s: XLALCreateDetectorStateSeries(%d) failed.\n", __func__, numSteps );
XLAL_ERROR_NULL ( XLAL_EFUNC );
}
/* enter detector-info into the head of the state-vector */
ret->detector = (*detector);
/* set 'time-span' associated with each timestamp */
ret->deltaT = timestamps->deltaT;
/* set SSB coordinate system used: EQUATORIAL for Earth-based, ECLIPTIC for LISA */
if ( detector->frDetector.prefix[0] == 'Z' ) /* LISA */
ret->system = COORDINATESYSTEM_ECLIPTIC;
else /* Earth-based */
ret->system = COORDINATESYSTEM_EQUATORIAL;
/* now fill all the vector-entries corresponding to different timestamps */
UINT4 i;
for ( i=0; i < numSteps; i++ )
{
BarycenterInput baryinput;
EmissionTime emit;
DetectorState *state = &(ret->data[i]);
EarthState *earth = &(state->earthState);
LIGOTimeGPS tgps;
/* shift timestamp by tOffset */
tgps = timestamps->data[i];
XLALGPSAdd(&tgps, tOffset);
/*----- first get earth-state */
if ( XLALBarycenterEarth ( earth, &tgps, edat ) != XLAL_SUCCESS ) {
XLALDestroyDetectorStateSeries ( ret );
XLALPrintError("%s: XLALBarycenterEarth() failed with xlalErrno=%d\n", __func__, xlalErrno );
XLAL_ERROR_NULL ( XLAL_EFAILED );
}
/*----- then get detector-specific info */
baryinput.tgps = tgps;
baryinput.site = (*detector);
baryinput.site.location[0] /= LAL_C_SI;
baryinput.site.location[1] /= LAL_C_SI;
baryinput.site.location[2] /= LAL_C_SI;
baryinput.alpha = baryinput.delta = 0; /* irrelevant */
baryinput.dInv = 0;
if ( XLALBarycenter ( &emit, &baryinput, earth) != XLAL_SUCCESS ) {
XLALDestroyDetectorStateSeries( ret );
XLALPrintError("%s: XLALBarycenterEarth() failed with xlalErrno=%d\n", __func__, xlalErrno );
XLAL_ERROR_NULL ( XLAL_EFAILED );
}
/*----- extract the output-data from this */
UINT4 j;
for (j=0; j < 3; j++) /* copy detector's position and velocity */
{
state->rDetector[j] = emit.rDetector[j];
state->vDetector[j] = emit.vDetector[j];
} /* for j < 3 */
/* local mean sidereal time = GMST + longitude */
state->LMST = earth->gmstRad + detector->frDetector.vertexLongitudeRadians;
state->LMST = fmod (state->LMST, LAL_TWOPI ); /* normalize */
/* insert timestamp */
state->tGPS = tgps;
/* compute the detector-tensor at this time-stamp in SSB-fixed Cartesian coordinates
* [EQUATORIAL for Earth-based, ECLIPTIC for LISA]
*/
if ( XLALFillDetectorTensor ( state, detector ) != 0 ) {
XLALDestroyDetectorStateSeries(ret);
XLALPrintError ( "%s: XLALFillDetectorTensor() failed ... errno = %d\n\n", __func__, xlalErrno );
XLAL_ERROR_NULL ( XLAL_EFUNC );
}
} /* for i < numSteps */
/* return result */
return ret;
} /* XLALGetDetectorStates() */
/**
* Very simple test: pick random skyposition, compute a_i, b_i using
* once LALComputeAM() and once LALNewGetAMCoeffs(), and look at the errors
* sum_i (a_i - a_i')^2
*/
int main(int argc, char *argv[])
{
LALStatus XLAL_INIT_DECL(status);
int opt; /* Command-line option. */
LIGOTimeGPS startTime = {714180733, 0};
REAL8 duration = 180000; /* 50 hours */
REAL8 Tsft = 1800; /* assume 30min SFTs */
LIGOTimeGPSVector *timestamps = NULL;
DetectorStateSeries *detStates = NULL;
SkyPosition XLAL_INIT_DECL(skypos);
EphemerisData XLAL_INIT_DECL(edat);
BarycenterInput XLAL_INIT_DECL(baryinput);
LALDetector *det = NULL;
AMCoeffs XLAL_INIT_DECL(AMold);
AMCoeffs XLAL_INIT_DECL(AMnew1);
AMCoeffs XLAL_INIT_DECL(AMnew2);
REAL8 alpha, delta;
AMCoeffsParams XLAL_INIT_DECL(amParams);
EarthState earth;
UINT4 i;
REAL8 maxerr01, maxerr02, maxerr12, averr01, averr02, averr12;
REAL8 tolerance = 1e-2; /* be generous: allow 1% error */
struct tms buf;
const CHAR *sites[] = {"H1", "L1", "V2", "G1", "T1" };
REAL8 sinzeta; /* zeta = IFO opening angle */
UINT4 pickedSite;
BOOLEAN ignoreErrors = 0; /* Don't fail if tolerance exceeded */
UINT4 numChecks = 1; /* Number of times to check */
char earthEphem[] = TEST_DATA_DIR "earth00-19-DE405.dat.gz";
char sunEphem[] = TEST_DATA_DIR "sun00-19-DE405.dat.gz";
/* ----- old testing code to use 9 degree earth rotations ----- */
/* startTime.gpsSeconds = 714275242;
duration = 86164;
Tsft = 2154.1; */
while ((opt = LALgetopt( argc, argv, "n:qv:" )) != -1) {
switch (opt) {
case 'v': /* set lalDebugLevel */
break;
case 'q': /* don't fail if tolerance exceeded */
ignoreErrors = 1;
break;
case 'n': /* number of times to check */
numChecks = atoi( LALoptarg );
break;
}
}
/* init random-generator */
srand ( times(&buf) );
/* ----- init ephemeris ----- */
edat.ephiles.earthEphemeris = earthEphem;
edat.ephiles.sunEphemeris = sunEphem;
SUB ( LALInitBarycenter(&status, &edat), &status);
/* ----- get timestamps ----- */
SUB ( LALMakeTimestamps ( &status, ×tamps, startTime, duration, Tsft ), &status );
/* ----- allocate memory for AM-coeffs ----- */
AMold.a = XLALCreateREAL4Vector ( timestamps->length );
AMold.b = XLALCreateREAL4Vector ( timestamps->length );
AMnew1.a = XLALCreateREAL4Vector ( timestamps->length );
AMnew1.b = XLALCreateREAL4Vector ( timestamps->length );
AMnew2.a = XLALCreateREAL4Vector ( timestamps->length );
AMnew2.b = XLALCreateREAL4Vector ( timestamps->length );
while ( numChecks-- )
{
/* ----- pick detector-site at random ----- */
pickedSite = floor( 5 * (1.0 * rand() / (RAND_MAX + 1.0) ) ); /* int in [0,5) */
/* NOTE: contrary to ComputeAM() and LALGetAMCoffs(), the new function LALNewGetAMCoeffs()
* computes 'a * sinzeta' and 'b * sinzeta': for the comparison we therefore need to correct
* for GEO's opening-angle of 94.33degrees [JKS98]: */
if ( ! strcmp ( sites[pickedSite], "G1" ) )
sinzeta = 0.997146;
else
sinzeta = 1;
if ( ( det = XLALGetSiteInfo ( sites[pickedSite] )) == NULL )
{
XLALPrintError ("\nCall to XLALGetSiteInfo() has failed for site = '%s'... \n\n",
sites[pickedSite]);
return NEWGETAMCOEFFSTEST_ESUB;
}
/* ----- pick skyposition at random ----- */
alpha = LAL_TWOPI * (1.0 * rand() / ( RAND_MAX + 1.0 ) ); /* uniform in [0, 2pi) */
delta = LAL_PI_2 - acos ( 1 - 2.0 * rand()/RAND_MAX ); /* sin(delta) uniform in [-1,1] */
/* ----- old testing code to put source overhead ----- */
/* alpha = det->frDetector.vertexLongitudeRadians;
delta = det->frDetector.vertexLatitudeRadians; */
/* ===== compute AM-coeffs the 'old way': ===== */
baryinput.site.location[0] = det->location[0]/LAL_C_SI;
baryinput.site.location[1] = det->location[1]/LAL_C_SI;
baryinput.site.location[2] = det->location[2]/LAL_C_SI;
baryinput.alpha = alpha;
baryinput.delta = delta;
baryinput.dInv = 0.e0;
/* amParams structure to compute a(t) and b(t) */
amParams.das = (LALDetAndSource *)LALMalloc(sizeof(LALDetAndSource));
amParams.das->pSource = (LALSource *)LALMalloc(sizeof(LALSource));
amParams.baryinput = &baryinput;
amParams.earth = &earth;
amParams.edat = &edat;
amParams.das->pDetector = det;
amParams.das->pSource->equatorialCoords.longitude = alpha;
amParams.das->pSource->equatorialCoords.latitude = delta;
amParams.das->pSource->orientation = 0.0;
amParams.das->pSource->equatorialCoords.system = COORDINATESYSTEM_EQUATORIAL;
amParams.polAngle = 0;
SUB (LALComputeAM ( &status, &AMold, timestamps->data, &amParams), &status);
/* ===== compute AM-coeffs the 'new way' using LALNewGetAMCoeffs() */
/* ----- get detector-state series ----- */
SUB ( LALGetDetectorStates (&status, &detStates, timestamps, det, &edat, 0 ), &status );
skypos.system = COORDINATESYSTEM_EQUATORIAL;
skypos.longitude = alpha;
skypos.latitude = delta;
/* the 'new' and the 'newer' way ... */
SUB ( LALGetAMCoeffs ( &status, &AMnew1, detStates, skypos ), &status ); /* 'new1' */
SUB ( LALNewGetAMCoeffs ( &status, &AMnew2, detStates, skypos ), &status ); /* 'new2' */
/* ===== analyse relative errors ===== */
maxerr01 = maxerr02 = maxerr12 = 0; /* errors between 0='old', 1='new1', 2='new2' */
averr01 = averr02 = averr12 = 0;
for ( i=0; i < timestamps->length; i ++ )
{
/* printf("GPS time: %d s %d ns; GMST in radians: %f\n",
detStates->data[i].tGPS.gpsSeconds,
detStates->data[i].tGPS.gpsNanoSeconds,
fmod(detStates->data[i].earthState.gmstRad,LAL_TWOPI));
printf("Old AM coeffs: a=%f, b=%f\nNew AM coeffs: a=%f, b=%f\nNEWER AM coeffs: a=%f b=%f",
AMold.a->data[i], AMold.b->data[i],
AMnew.a->data[i], AMnew.b->data[i],
AMnewer.a->data[i], AMnewer.b->data[i]); */
REAL8 thisErr;
/* compare 0-1 */
thisErr = sqrt( SQ ( AMold.a->data[i] - AMnew1.a->data[i] ) / AMold.A );
averr01 += thisErr;
maxerr01 = MYMAX( thisErr, maxerr01 );
thisErr = sqrt( SQ ( AMold.b->data[i] - AMnew1.b->data[i] ) / AMold.B );
averr01 += thisErr;
maxerr01 = MYMAX( thisErr, maxerr01 );
/* compare 0-2 */
thisErr = sqrt( SQ ( AMold.a->data[i] - AMnew2.a->data[i]/sinzeta ) / AMold.A );
averr02 += thisErr;
maxerr02 = MYMAX( thisErr, maxerr02 );
thisErr = sqrt( SQ ( AMold.b->data[i] - AMnew2.b->data[i]/sinzeta ) / AMold.B );
averr02 += thisErr;
maxerr02 = MYMAX( thisErr, maxerr02 );
/* compare 1-2 */
thisErr = sqrt( SQ ( AMnew1.a->data[i] - AMnew2.a->data[i]/sinzeta ) / AMold.A );
averr12 += thisErr;
maxerr12 = MYMAX( thisErr, maxerr12 );
thisErr = sqrt( SQ ( AMnew1.b->data[i] - AMnew2.b->data[i]/sinzeta ) / AMold.B );
averr12 += thisErr;
maxerr12 = MYMAX( thisErr, maxerr12 );
}
averr01 /= 2.0 * timestamps->length;
averr02 /= 2.0 * timestamps->length;
averr12 /= 2.0 * timestamps->length;
if ( lalDebugLevel )
{
printf ("Parameters: IFO = %s, skypos = [%g, %g]\n", sites[pickedSite], alpha, delta );
printf ("Maximal relative errors: maxerr(0-1) = %g %%, maxerr(0-2) = %g %% maxerr(1-2) = %g %%\n",
100.0 * maxerr01, 100.0 * maxerr02, 100.0 * maxerr12 );
printf ("Average relative errors: averr(0-1) = %g %%, averr(0-2) = %g %% averr(1-2) = %g %%\n",
100.0 * averr01, 100.0 * averr02, 100.0 * averr12 );
}
else
printf ("%d %g %g \t %g %g %g \t %g %g %g\n", pickedSite, alpha, delta, averr01, averr02, averr12, maxerr01, maxerr02, maxerr12);
if ( (averr01 > tolerance) || (averr02 > tolerance) || (averr12 > tolerance)
|| (maxerr01 > tolerance) ||(maxerr02 > tolerance) || (maxerr12 > tolerance) )
{
XLALPrintError ("Maximal error-tolerance of %g %% was exceeded!\n", 100.0 * tolerance );
if (!ignoreErrors)
return 1;
}
if ( lalDebugLevel )
printf("%d checks left\n", numChecks);
/* ---- Clean up things that were created in this loop ---- */
XLALDestroyDetectorStateSeries ( detStates );
detStates = NULL;
LALFree ( det );
LALFree ( amParams.das->pSource );
LALFree ( amParams.das );
}
/* ----- free memory ----- */
XLALDestroyTimestampVector ( timestamps );
XLALDestroyREAL4Vector ( AMold.a );
XLALDestroyREAL4Vector ( AMold.b );
XLALDestroyREAL4Vector ( AMnew1.a );
XLALDestroyREAL4Vector ( AMnew1.b );
XLALDestroyREAL4Vector ( AMnew2.a );
XLALDestroyREAL4Vector ( AMnew2.b );
LALFree(edat.ephemE);
LALFree(edat.ephemS);
LALCheckMemoryLeaks();
return 0; /* OK */
} /* main() */
int
main(int argc, char *argv[])
{
LALStatus status = blank_status;
ConfigVariables XLAL_INIT_DECL(config);
UserVariables_t XLAL_INIT_DECL(uvar);
/* register user-variables */
XLAL_CHECK ( XLALInitUserVars ( &uvar ) == XLAL_SUCCESS, XLAL_EFUNC );
/* read cmdline & cfgfile */
BOOLEAN should_exit = 0;
XLAL_CHECK( XLALUserVarReadAllInput( &should_exit, argc, argv ) == XLAL_SUCCESS, XLAL_EFUNC );
if ( should_exit ) {
exit(1);
}
if ( uvar.version )
{
XLALOutputVersionString ( stdout, lalDebugLevel );
exit(0);
}
/* basic setup and initializations */
XLAL_CHECK ( XLALInitCode( &config, &uvar, argv[0] ) == XLAL_SUCCESS, XLAL_EFUNC );
/* ----- allocate memory for AM-coeffs ----- */
AMCoeffs AMold, AMnew1, AMnew2; /**< containers holding AM-coefs computed by 3 different AM functions */
AMold.a = XLALCreateREAL4Vector ( 1 );
AMold.b = XLALCreateREAL4Vector ( 1 );
AMnew1.a = XLALCreateREAL4Vector ( 1 );
AMnew1.b = XLALCreateREAL4Vector ( 1 );
AMnew2.a = XLALCreateREAL4Vector ( 1 );
AMnew2.b = XLALCreateREAL4Vector ( 1 );
XLAL_CHECK ( AMold.a && AMold.b && AMnew1.a && AMnew1.b && AMnew2.a && AMnew2.a, XLAL_ENOMEM, "Failed to XLALCreateREAL4Vector ( 1 )\n" );
/* ----- get detector-state series ----- */
DetectorStateSeries *detStates = NULL;
XLAL_CHECK ( (detStates = XLALGetDetectorStates ( config.timestamps, config.det, config.edat, 0 )) != NULL, XLAL_EFUNC );
/* ----- compute associated SSB timing info ----- */
SSBtimes *tSSB = XLALGetSSBtimes ( detStates, config.skypos, config.timeGPS, SSBPREC_RELATIVISTIC );
XLAL_CHECK ( tSSB != NULL, XLAL_EFUNC, "XLALGetSSBtimes() failed with xlalErrno = %d\n", xlalErrno );
/* ===== 1) compute AM-coeffs the 'old way': [used in CFSv1] ===== */
BarycenterInput XLAL_INIT_DECL(baryinput);
AMCoeffsParams XLAL_INIT_DECL(amParams);
EarthState earth;
baryinput.site.location[0] = config.det->location[0]/LAL_C_SI;
baryinput.site.location[1] = config.det->location[1]/LAL_C_SI;
baryinput.site.location[2] = config.det->location[2]/LAL_C_SI;
baryinput.alpha = config.skypos.longitude;
baryinput.delta = config.skypos.latitude;
baryinput.dInv = 0.e0;
/* amParams structure to compute a(t) and b(t) */
amParams.das = XLALMalloc(sizeof(*amParams.das));
amParams.das->pSource = XLALMalloc(sizeof(*amParams.das->pSource));
amParams.baryinput = &baryinput;
amParams.earth = &earth;
amParams.edat = config.edat;
amParams.das->pDetector = config.det;
amParams.das->pSource->equatorialCoords.longitude = config.skypos.longitude;
amParams.das->pSource->equatorialCoords.latitude = config.skypos.latitude;
amParams.das->pSource->orientation = 0.0;
amParams.das->pSource->equatorialCoords.system = COORDINATESYSTEM_EQUATORIAL;
amParams.polAngle = 0;
LAL_CALL ( LALComputeAM ( &status, &AMold, config.timestamps->data, &amParams), &status);
XLALFree ( amParams.das->pSource );
XLALFree ( amParams.das );
/* ===== 2) compute AM-coeffs the 'new way' using LALNewGetAMCoeffs() */
LALGetAMCoeffs ( &status, &AMnew1, detStates, config.skypos );
if ( status.statusCode ) {
XLALPrintError ("%s: call to LALGetAMCoeffs() failed, status = %d\n\n", __func__, status.statusCode );
XLAL_ERROR ( status.statusCode & XLAL_EFUNC );
}
/* ===== 3) compute AM-coeffs the 'newer way' using LALNewGetAMCoeffs() [used in CFSv2] */
LALNewGetAMCoeffs ( &status, &AMnew2, detStates, config.skypos );
if ( status.statusCode ) {
XLALPrintError ("%s: call to LALNewGetAMCoeffs() failed, status = %d\n\n", __func__, status.statusCode );
XLAL_ERROR ( status.statusCode & XLAL_EFUNC );
}
/* ===== 4) use standalone version of the above [used in FstatMetric_v2] */
REAL8 a0,b0;
if ( XLALComputeAntennaPatternCoeffs ( &a0, &b0, &config.skypos, &config.timeGPS, config.det, config.edat ) != XLAL_SUCCESS ) {
XLALPrintError ("%s: XLALComputeAntennaPatternCoeffs() failed.\n", __func__ );
XLAL_ERROR ( XLAL_EFUNC );
}
/* ==================== output the results ==================== */
printf ("\n");
printf ("----- Input parameters:\n");
printf ("tGPS = { %d, %d }\n", config.timeGPS.gpsSeconds, config.timeGPS.gpsNanoSeconds );
printf ("Detector = %s\n", config.det->frDetector.name );
printf ("Sky position: longitude = %g rad, latitude = %g rad [equatorial coordinates]\n", config.skypos.longitude, config.skypos.latitude );
printf ("\n");
printf ("----- Antenna pattern functions (a,b):\n");
printf ("LALComputeAM: ( %-12.8g, %-12.8g) [REAL4]\n", AMold.a->data[0], AMold.b->data[0] );
printf ("LALGetAMCoeffs: ( %-12.8g, %-12.8g) [REAL4]\n", AMnew1.a->data[0], AMnew1.b->data[0] );
printf ("LALNewGetAMCoeffs: ( %-12.8g, %-12.8g) [REAL4]\n", AMnew2.a->data[0]/config.sinzeta, AMnew2.b->data[0]/config.sinzeta );
printf ("XLALComputeAntennaPatternCoeffs: ( %-12.8g, %-12.8g) [REAL8]\n", a0/config.sinzeta, b0/config.sinzeta );
printf ("\n");
printf ("----- Detector & Earth state:\n");
REAL8 *pos = detStates->data[0].rDetector;
printf ("Detector position [ICRS J2000. Units=sec]: rDet = {%g, %g, %g}\n", pos[0], pos[1], pos[2] );
REAL8 *vel = detStates->data[0].vDetector;
printf ("Detector velocity [ICRS J2000. Units=c]: vDet = {%g, %g, %g}\n", vel[0], vel[1], vel[2] );
printf ("Local mean sideral time: LMST = %g rad\n", detStates->data[0].LMST);
printf ("\n");
printf ("----- SSB timing data:\n");
printf ("TOA difference tSSB - tDet = %g s\n", tSSB->DeltaT->data[0] );
printf ("TOA rate of change dtSSB/dtDet - 1 = %g\n", tSSB->Tdot->data[0] - 1.0 );
printf ("\n\n");
/* ----- done: free all memory */
XLAL_CHECK ( XLALDestroyConfig( &config ) == XLAL_SUCCESS, XLAL_EFUNC );
XLALDestroyDetectorStateSeries ( detStates );
XLALDestroyREAL4Vector ( AMold.a );
XLALDestroyREAL4Vector ( AMold.b );
XLALDestroyREAL4Vector ( AMnew1.a );
XLALDestroyREAL4Vector ( AMnew1.b );
XLALDestroyREAL4Vector ( AMnew2.a );
XLALDestroyREAL4Vector ( AMnew2.b );
XLALDestroyREAL8Vector ( tSSB->DeltaT );
XLALDestroyREAL8Vector ( tSSB->Tdot );
XLALFree (tSSB);
LALCheckMemoryLeaks();
return 0;
} /* main */
/**
* Very simple test: pick random skyposition, compute a_i, b_i using
* once LALComputeAM() and once LALGetAMCoeffs(), and look at the errors
* sum_i (a_i - a_i')^2
*/
int main(int argc, char *argv[])
{
LALStatus XLAL_INIT_DECL(status);
LIGOTimeGPS startTime = {714180733, 0};
REAL8 duration = 180000; /* 50 hours */
REAL8 Tsft = 1800; /* assume 30min SFTs */
LIGOTimeGPSVector *timestamps = NULL;
DetectorStateSeries *detStates = NULL;
SkyPosition XLAL_INIT_DECL(skypos);
EphemerisData XLAL_INIT_DECL(edat);
BarycenterInput XLAL_INIT_DECL(baryinput);
LALDetector *det = NULL;
AMCoeffs XLAL_INIT_DECL(AMold);
AMCoeffs XLAL_INIT_DECL(AMnew);
REAL8 alpha, delta;
AMCoeffsParams XLAL_INIT_DECL(amParams);
EarthState earth;
UINT4 i;
REAL8 maxerr_a, maxerr_b, averr_a, averr_b;
REAL8 tolerance = 1e-2; /* be generous: allow 1% error */
struct tms buf;
const CHAR *sites[] = {"H1", "L1", "V2", "G1", "T1" };
UINT4 pickedSite;
char earthEphem[] = TEST_DATA_DIR "earth00-19-DE405.dat.gz";
char sunEphem[] = TEST_DATA_DIR "sun00-19-DE405.dat.gz";
if ( argc == 2 && !strcmp(argv[1], "-v1") )
/* init random-generator */
srand ( times(&buf) );
/* ----- init ephemeris ----- */
edat.ephiles.earthEphemeris = earthEphem;
edat.ephiles.sunEphemeris = sunEphem;
SUB ( LALInitBarycenter(&status, &edat), &status);
/* ----- get timestamps ----- */
SUB ( LALMakeTimestamps ( &status, ×tamps, startTime, duration, Tsft ), &status );
/* ----- allocate memory for AM-coeffs ----- */
AMold.a = XLALCreateREAL4Vector ( timestamps->length );
AMold.b = XLALCreateREAL4Vector ( timestamps->length );
AMnew.a = XLALCreateREAL4Vector ( timestamps->length );
AMnew.b = XLALCreateREAL4Vector ( timestamps->length );
/* ----- pick detector-site at random ----- */
pickedSite = floor( 5 * (1.0 * rand() / (RAND_MAX + 1.0) ) ); /* int in [0,5) */
if ( ( det = XLALGetSiteInfo ( sites[pickedSite] )) == NULL )
{
XLALPrintError ("\nCall to XLALGetSiteInfo() has failed for site = '%s'... \n\n",
sites[pickedSite]);
return GETAMCOEFFSTEST_ESUB;
}
/* ----- pick skyposition at random ----- */
alpha = LAL_TWOPI * (1.0 * rand() / ( RAND_MAX + 1.0 ) ); /* uniform in [0, 2pi) */
delta = LAL_PI_2 - acos ( 1 - 2.0 * rand()/RAND_MAX ); /* sin(delta) uniform in [-1,1] */
/* ===== compute AM-coeffs the 'old way': ===== */
baryinput.site.location[0] = det->location[0]/LAL_C_SI;
baryinput.site.location[1] = det->location[1]/LAL_C_SI;
baryinput.site.location[2] = det->location[2]/LAL_C_SI;
baryinput.alpha = alpha;
baryinput.delta = delta;
baryinput.dInv = 0.e0;
/* amParams structure to compute a(t) and b(t) */
amParams.das = (LALDetAndSource *)LALMalloc(sizeof(LALDetAndSource));
amParams.das->pSource = (LALSource *)LALMalloc(sizeof(LALSource));
amParams.baryinput = &baryinput;
amParams.earth = &earth;
amParams.edat = &edat;
amParams.das->pDetector = det;
amParams.das->pSource->equatorialCoords.longitude = alpha;
amParams.das->pSource->equatorialCoords.latitude = delta;
amParams.das->pSource->orientation = 0.0;
amParams.das->pSource->equatorialCoords.system = COORDINATESYSTEM_EQUATORIAL;
amParams.polAngle = 0;
SUB (LALComputeAM ( &status, &AMold, timestamps->data, &amParams), &status);
/* ===== compute AM-coeffs the 'new way' using LALGetAMCoeffs() */
/* ----- get detector-state series ----- */
SUB ( LALGetDetectorStates (&status, &detStates, timestamps, det, &edat, 0 ), &status );
skypos.system = COORDINATESYSTEM_EQUATORIAL;
skypos.longitude = alpha;
skypos.latitude = delta;
SUB ( LALGetAMCoeffs ( &status, &AMnew, detStates, skypos ), &status );
/* ===== analyse relative error ===== */
maxerr_a = maxerr_b = averr_a = averr_b = 0;
for ( i=0; i < timestamps->length; i ++ )
{
REAL8 thisErr;
thisErr = sqrt( SQ ( AMold.a->data[i] - AMnew.a->data[i] ) / AMold.A );
averr_a += thisErr;
maxerr_a = MYMAX( thisErr, maxerr_a );
thisErr = sqrt( SQ ( AMold.b->data[i] - AMnew.b->data[i] ) / AMold.B );
averr_b += thisErr;
maxerr_b = MYMAX( thisErr, maxerr_b );
}
averr_a /= timestamps->length;
averr_b /= timestamps->length;
if ( lalDebugLevel )
{
printf ("Parameters: IFO = %s, skypos = [%g, %g]\n", sites[pickedSite], alpha, delta );
printf ("Maximal relative errors: maxerr(a) = %g %%, maxerr(b) = %g %% \n",
100.0 * maxerr_a, 100.0 * maxerr_b);
printf ("Average relative errors: averr(a) = %g %%, averr(b) = %g %% \n",
100.0 * averr_a, 100.0 * averr_b );
}
else
printf ("%d %g %g %g %g %g %g \n", pickedSite, alpha, delta, averr_a, averr_b, maxerr_a, maxerr_b);
if ( (averr_a > tolerance) || (averr_b > tolerance) || (maxerr_a > tolerance) ||(maxerr_b > tolerance))
{
XLALPrintError ("Maximal error-tolerance of %g %% was exceeded!\n", 100.0 * tolerance );
return 1;
}
/* ----- free memory ----- */
XLALDestroyTimestampVector ( timestamps );
XLALDestroyREAL4Vector ( AMold.a );
XLALDestroyREAL4Vector ( AMold.b );
XLALDestroyREAL4Vector ( AMnew.a );
XLALDestroyREAL4Vector ( AMnew.b );
LALFree ( det );
XLALDestroyDetectorStateSeries ( detStates );
LALFree ( amParams.das->pSource );
LALFree ( amParams.das );
LALFree(edat.ephemE);
LALFree(edat.ephemS);
LALCheckMemoryLeaks();
return 0; /* OK */
} /* main() */
/**
* Simulate a pulsar signal to best accuracy possible.
* \author Reinhard Prix
* \date 2005
*
* The motivation for this function is to provide functions to
* simulate pulsar signals <em>with the best possible accuracy</em>,
* i.e. using no approximations, contrary to LALGeneratePulsarSignal().
*
* Obviously this is not meant as a fast code to be used in a Monte-Carlo
* simulation, but rather as a <em>reference</em> to compare other (faster)
* functions agains, in order to be able to gauge the quality of a given
* signal-generation routine.
*
* We want to calculate \f$h(t)\f$, given by
* \f[
* h(t) = F_+(t)\, h_+(t) + F_\times(t) \,h_\times(t)\,,
* \f]
* where \f$F_+\f$ and \f$F_x\f$ are called the <em>beam-pattern</em> functions,
* which depend of the wave polarization \f$\psi\f$,
* the source position \f$\alpha\f$, \f$\delta\f$ and the detector position and
* orientation (\f$\gamma\f$, \f$\lambda\f$, \f$L\f$ and \f$\xi\f$). The expressions for
* the beam-pattern functions are given in \cite JKS98 , which we write as
* \f{eqnarray}{
* F_+(t) = \sin \zeta \cos 2\psi \, a(t) + \sin \zeta \sin 2\psi \, b(t)\,,\\
* F_\times(t) = \sin\zeta \cos 2\psi \,b(t) - \sin\zeta \sin 2\psi \, a(t) \,,
* \f}
* where \f$\zeta\f$ is the angle between the interferometer arms, and
* \f{eqnarray}{
* a(t) &=& a_1 \cos[ 2 (\alpha - T)) ] + a_2 \sin[ 2(\alpha - T)]
* + a_3 \cos[ \alpha - T ] + a_4 \sin [ \alpha - T ] + a_5\,,\\
* b(t) &=& b_1 \cos[ 2(\alpha - T)] + b_2 \sin[ 2(\alpha - T) ]
* + b_3 \cos[ \alpha - T ] + b_4 \sin[ \alpha - T]\,,
* \f}
* where \f$T\f$ is the local (mean) sidereal time of the detector, and the
* time-independent coefficients \f$a_i\f$ and \f$b_i\f$ are given by
* \f{eqnarray}{
* a_1 &=& \frac{1}{16} \sin 2\gamma \,(3- \cos 2\lambda)\,(3 - \cos 2\delta)\,,\\
* a_2 &=& -\frac{1}{4}\cos 2\gamma \,\sin \lambda \,(3 - \cos 2\delta) \,,\\
* a_3 &=& \frac{1}{4} \sin 2\gamma \,\sin 2\lambda \,\sin 2\delta \,\\
* a_4 &=& -\frac{1}{2} \cos 2\gamma \,\cos \lambda \,\sin 2 \delta\,,\\
* a_5 &=& \frac{3}{4} \sin 2\gamma \, \cos^2 \lambda \,\cos^2 \delta\,,
* \f}
* and
* \f{eqnarray}{
* b_1 &=& \cos 2\gamma \,\sin \lambda \,\sin \delta\,,\\
* b_2 &=& \frac{1}{4} \sin 2\gamma \,(3-\cos 2\lambda)\, \sin \delta\,,\\
* b_3 &=& \cos 2\gamma \,\cos \lambda \,\cos\delta \,, \\
* b_4 &=& \frac{1}{2} \sin2\gamma \,\sin 2\lambda \,\cos\delta\,,
* \f}
*
* The source model considered is a plane-wave
* \f{eqnarray}{
* h_+(t) &=& A_+\, \cos \Psi(t)\,,\\
* h_\times(t) &=& A_\times \, \sin \Psi(t)\,,
* \f}
* where the wave-phase is \f$\Psi(t) = \Phi_0 + \Phi(t)\f$, and for an
* isolated pulsar we have
* \f{equation}{
* \Phi(t) = 2\pi \left[\sum_{s=0} \frac{f^{(s)}(\tau_\mathrm{ref})}{
* (s+1)!} \left( \tau(t) - \tau_\mathrm{ref} \right)^{s+1} \right]\,,
* \f}
* where \f$\tau_\mathrm{ref}\f$ is the "reference time" for the definition
* of the pulsar-parameters \f$f^{(s)}\f$ in the solar-system barycenter
* (SSB), and \f$\tau(t)\f$ is the SSB-time of the phase arriving at the
* detector at UTC-time \f$t\f$, which depends on the source-position
* (\f$\alpha\f$, \f$\delta\f$) and the detector-position, namely
* \f{equation}{
* \tau (t) = t + \frac{ \vec{r}(t)\cdot\vec{n}}{c}\,,
* \f}
* where \f$\vec{r}(t)\f$ is the vector from SSB to the detector, and \f$\vec{n}\f$
* is the unit-vector pointing <em>to</em> the source.
*
* This is a standalone "clean-room" implementation using no other
* outside-functions <em>except</em> for LALGPStoLMST1() to calculate
* the local (mean) sidereal time at the detector for given GPS-time,
* (which I double-checked with an independent Mathematica script),
* and and XLALBarycenter() to calculate \f$\tau(t)\f$.
*
* NOTE: currently only isolated pulsars are supported
*
* NOTE2: we don't really use the highest possible accuracy right now,
* as we blatently neglect all relativistic timing effects (i.e. using dT=v.n/c)
*
* NOTE3: no heterodyning is performed here, the time-series is generated and sampled
* at the given rate, that's all! ==\> the caller needs to make sure about the
* right sampling rate to use (-\>aliasing) and do the proper post-treatment...
*
*/
REAL4TimeSeries *
XLALSimulateExactPulsarSignal ( const PulsarSignalParams *params )
{
XLAL_CHECK_NULL ( params != NULL, XLAL_EINVAL, "Invalid NULL input 'params'\n");
XLAL_CHECK_NULL ( params->samplingRate > 0, XLAL_EDOM, "Sampling rate must be positive, got samplingRate = %g\n", params->samplingRate );
/* don't accept heterodyning frequency */
XLAL_CHECK_NULL ( params->fHeterodyne == 0, XLAL_EINVAL, "Heterodyning frequency must be set to 0, got params->fHeterodyne = %g\n", params->fHeterodyne );
UINT4 numSpins = 3;
/* get timestamps of timeseries plus detector-states */
REAL8 dt = 1.0 / params->samplingRate;
LIGOTimeGPSVector *timestamps;
XLAL_CHECK_NULL ( (timestamps = XLALMakeTimestamps ( params->startTimeGPS, params->duration, dt, 0 )) != NULL, XLAL_EFUNC );
UINT4 numSteps = timestamps->length;
DetectorStateSeries *detStates = XLALGetDetectorStates ( timestamps, params->site, params->ephemerides, 0 );
XLAL_CHECK_NULL ( detStates != NULL, XLAL_EFUNC, "XLALGetDetectorStates() failed.\n");
XLALDestroyTimestampVector ( timestamps );
timestamps = NULL;
AMCoeffs *amcoe = XLALComputeAMCoeffs ( detStates, params->pulsar.position );
XLAL_CHECK_NULL ( amcoe != NULL, XLAL_EFUNC, "XLALComputeAMCoeffs() failed.\n");
/* create output timeseries (FIXME: should really know *detector* here, not just site!!) */
const LALFrDetector *site = &(params->site->frDetector);
CHAR *channel = XLALGetChannelPrefix ( site->name );
XLAL_CHECK_NULL ( channel != NULL, XLAL_EFUNC, "XLALGetChannelPrefix( %s ) failed.\n", site->name );
REAL4TimeSeries *ts = XLALCreateREAL4TimeSeries ( channel, &(detStates->data[0].tGPS), 0, dt, &emptyUnit, numSteps );
XLAL_CHECK_NULL ( ts != NULL, XLAL_EFUNC, "XLALCreateREAL4TimeSeries() failed.\n");
XLALFree ( channel );
channel = NULL;
/* orientation of detector arms */
REAL8 xAzi = site->xArmAzimuthRadians;
REAL8 yAzi = site->yArmAzimuthRadians;
REAL8 Zeta = xAzi - yAzi;
if (Zeta < 0) {
Zeta = -Zeta;
}
if ( params->site->type == LALDETECTORTYPE_CYLBAR ) {
Zeta = LAL_PI_2;
}
REAL8 sinZeta = sin(Zeta);
/* get source skyposition */
REAL8 Alpha = params->pulsar.position.longitude;
REAL8 Delta = params->pulsar.position.latitude;
REAL8 vn[3];
vn[0] = cos(Delta) * cos(Alpha);
vn[1] = cos(Delta) * sin(Alpha);
vn[2] = sin(Delta);
/* get spin-parameters (restricted to maximally 3 spindowns right now) */
REAL8 phi0 = params->pulsar.phi0;
REAL8 f0 = params->pulsar.f0;
REAL8 f1dot = 0, f2dot = 0, f3dot = 0;
if ( params->pulsar.spindown && (params->pulsar.spindown->length > numSpins) ) {
XLAL_ERROR_NULL ( XLAL_EDOM, "Currently only supports up to %d spindowns!\n", numSpins );
}
if ( params->pulsar.spindown && (params->pulsar.spindown->length >= 3 ) ) {
f3dot = params->pulsar.spindown->data[2];
}
if ( params->pulsar.spindown && (params->pulsar.spindown->length >= 2 ) ) {
f2dot = params->pulsar.spindown->data[1];
}
if ( params->pulsar.spindown && (params->pulsar.spindown->length >= 1 ) ) {
f1dot = params->pulsar.spindown->data[0];
}
/* internally we always work with refTime = startTime->SSB, therefore
* we need to translate the pulsar spin-params and initial phase to the
* startTime
*/
REAL8 startTimeSSB = XLALGPSGetREAL8 ( &(detStates->data[0].tGPS) ) + SCALAR ( vn, detStates->data[0].rDetector );
REAL8 refTime;
if ( params->pulsar.refTime.gpsSeconds != 0 )
{
REAL8 refTime0 = XLALGPSGetREAL8 ( &(params->pulsar.refTime) );
REAL8 deltaRef = startTimeSSB - refTime0;
LIGOTimeGPS newEpoch;
PulsarSpins fkdotNew;
XLALGPSSetREAL8( &newEpoch, startTimeSSB );
PulsarSpins XLAL_INIT_DECL(fkdotOld);
fkdotOld[0] = f0;
fkdotOld[1] = f1dot;
fkdotOld[2] = f2dot;
fkdotOld[3] = f3dot;
REAL8 DeltaTau = XLALGPSDiff ( &newEpoch, &(params->pulsar.refTime) );
int ret = XLALExtrapolatePulsarSpins ( fkdotNew, fkdotOld, DeltaTau );
XLAL_CHECK_NULL ( ret == XLAL_SUCCESS, XLAL_EFUNC, "XLALExtrapolatePulsarSpins() failed.\n");
/* Finally, need to propagate phase */
phi0 += LAL_TWOPI * ( f0 * deltaRef
+ (1.0/2.0) * f1dot * deltaRef * deltaRef
+ (1.0/6.0) * f2dot * deltaRef * deltaRef * deltaRef
+ (1.0/24.0)* f3dot * deltaRef * deltaRef * deltaRef * deltaRef
);
f0 = fkdotNew[0];
f1dot = fkdotNew[1];
f2dot = fkdotNew[2];
f3dot = fkdotNew[3];
refTime = startTimeSSB;
} /* if refTime given */
else { /* if not given: use startTime -> SSB */
refTime = startTimeSSB;
}
/* get 4 amplitudes A_\mu */
REAL8 aPlus = sinZeta * params->pulsar.aPlus;
REAL8 aCross = sinZeta * params->pulsar.aCross;
REAL8 twopsi = 2.0 * params->pulsar.psi;
REAL8 A1 = aPlus * cos(phi0) * cos(twopsi) - aCross * sin(phi0) * sin(twopsi);
REAL8 A2 = aPlus * cos(phi0) * sin(twopsi) + aCross * sin(phi0) * cos(twopsi);
REAL8 A3 = -aPlus * sin(phi0) * cos(twopsi) - aCross * cos(phi0) * sin(twopsi);
REAL8 A4 = -aPlus * sin(phi0) * sin(twopsi) + aCross * cos(phi0) * cos(twopsi);
/* main loop: generate time-series */
for ( UINT4 i = 0; i < numSteps; i++)
{
LIGOTimeGPS *tiGPS = &(detStates->data[i].tGPS);
REAL8 ti = XLALGPSGetREAL8 ( tiGPS );
REAL8 deltati = ti - refTime;
REAL8 dT = SCALAR(vn, detStates->data[i].rDetector );
REAL8 taui = deltati + dT;
REAL8 phi_i = LAL_TWOPI * ( f0 * taui
+ (1.0/2.0) * f1dot * taui*taui
+ (1.0/6.0) * f2dot * taui*taui*taui
+ (1.0/24.0)* f3dot * taui*taui*taui*taui
);
REAL8 cosphi_i = cos(phi_i);
REAL8 sinphi_i = sin(phi_i);
REAL8 ai = amcoe->a->data[i];
REAL8 bi = amcoe->b->data[i];
REAL8 hi = A1 * ai * cosphi_i
+ A2 * bi * cosphi_i
+ A3 * ai * sinphi_i
+ A4 * bi * sinphi_i;
ts->data->data[i] = (REAL4)hi;
} /* for i < numSteps */
XLALDestroyDetectorStateSeries( detStates );
XLALDestroyAMCoeffs ( amcoe );
return ts;
} /* XLALSimulateExactPulsarSignal() */
