/** Create a DetectorStateSeries */
void
LALCreateDetectorStateSeries (LALStatus *status, /**< pointer to LALStatus structure */
DetectorStateSeries **vect, /**< output vector */
UINT4 length ) /**< number of entries */
{
DetectorStateSeries *ret = NULL;
INITSTATUS(status);
ASSERT ( vect, status, DETECTORSTATES_ENULL, DETECTORSTATES_MSGENULL);
ASSERT ( *vect == NULL, status, DETECTORSTATES_ENONULL, DETECTORSTATES_MSGENONULL);
if ( (ret = XLALCreateDetectorStateSeries ( length )) == NULL ) {
ABORT ( status, DETECTORSTATES_EXLAL, DETECTORSTATES_MSGEXLAL );
}
/* return result */
(*vect) = ret;
RETURN (status);
} /* LALCreateDetectorStateSeries() */
/**
* 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() */
