int main ( void )
{
const char *fn = __func__;
//LALStatus status = empty_status;
SFTtype *mySFT;
LIGOTimeGPS epoch = { 731210229, 0 };
REAL8 dFreq = 1.0 / 1800.0;
REAL8 f0 = 150.0 - 2.0 * dFreq;
/* init data array */
COMPLEX8 vals[] = {
crectf( -1.249241e-21, 1.194085e-21 ),
crectf( 2.207420e-21, 2.472366e-22 ),
crectf( 1.497939e-21, 6.593609e-22 ),
crectf( 3.544089e-20, -9.365807e-21 ),
crectf( 1.292773e-21, -1.402466e-21 )
};
UINT4 numBins = sizeof ( vals ) / sizeof(vals[0] );
if ( (mySFT = XLALCreateSFT ( numBins )) == NULL ) {
XLALPrintError ("%s: Failed to create test-SFT using XLALCreateSFT(), xlalErrno = %d\n", fn, xlalErrno );
return XLAL_EFAILED;
}
/* init header */
strcpy ( mySFT->name, "H1;testSFTRngmed" );
mySFT->epoch = epoch;
mySFT->f0 = f0;
mySFT->deltaF = dFreq;
/* we simply copy over these data-values into the SFT */
UINT4 iBin;
for ( iBin = 0; iBin < numBins; iBin ++ )
mySFT->data->data[iBin] = vals[iBin];
/* get memory for running-median vector */
REAL8FrequencySeries rngmed;
INIT_MEM ( rngmed );
XLAL_CHECK ( (rngmed.data = XLALCreateREAL8Vector ( numBins )) != NULL, XLAL_EFUNC, "Failed XLALCreateREAL8Vector ( %d )", numBins );
// ---------- Test running-median PSD estimation in simple blocksize cases
// ------------------------------------------------------------
// TEST 1: odd blocksize = 3
// ------------------------------------------------------------
UINT4 blockSize3 = 3;
/* reference result for 3-bin block running-median computed in octave:
octave> sft = [ \
-1.249241e-21 + 1.194085e-21i, \
2.207420e-21 + 2.472366e-22i, \
1.497939e-21 + 6.593609e-22i, \
3.544089e-20 - 9.365807e-21i, \
1.292773e-21 - 1.402466e-21i \
];
octave> periodo = abs(sft).^2;
octave> m1 = median ( periodo(1:3) ); m2 = median ( periodo(2:4) ); m3 = median ( periodo (3:5 ) );
octave> rngmed = [ m1, m1, m2, m3, m3 ];
octave> printf ("rngmedREF3 = { %.16g, %.16g, %.16g, %.16g, %.16g };\n", rngmed );
rngmedREF3[] = { 2.986442063306e-42, 2.986442063306e-42, 4.933828992779561e-42, 3.638172910684999e-42, 3.638172910684999e-42 };
*/
REAL8 rngmedREF3[] = { 2.986442063306e-42, 2.986442063306e-42, 4.933828992779561e-42, 3.638172910684999e-42, 3.638172910684999e-42 };
/* compute running median */
XLAL_CHECK ( XLALSFTtoRngmed ( &rngmed, mySFT, blockSize3 ) == XLAL_SUCCESS, XLAL_EFUNC, "XLALSFTtoRngmed() failed.");
/* get median->mean bias correction, needed for octave-reference results, to make
* them comparable to the bias-corrected results from LALSFTtoRngmed()
*/
REAL8 medianBias3 = XLALRngMedBias ( blockSize3 );
XLAL_CHECK ( xlalErrno == 0, XLAL_EFUNC, "XLALRngMedBias() failed.");
BOOLEAN pass = 1;
const CHAR *passStr;
printf ("%4s %22s %22s %8s <%g\n", "Bin", "rngmed(LAL)", "rngmed(Octave)", "relError", tol);
for (iBin=0; iBin < numBins; iBin ++ )
{
REAL8 rngmedVAL = rngmed.data->data[iBin];
REAL8 rngmedREF = rngmedREF3[iBin] / medianBias3; // apply median-bias correction
REAL8 relErr = REL_ERR ( rngmedREF, rngmedVAL );
if ( relErr > tol ) {
pass = 0;
passStr = "fail";
} else {
passStr = "OK.";
}
printf ("%4d %22.16g %22.16g %8.1g %s\n", iBin, rngmedVAL, rngmedREF, relErr, passStr );
} /* for iBin < numBins */
// ------------------------------------------------------------
// TEST 2: even blocksize = 4
// ------------------------------------------------------------
UINT4 blockSize4 = 4;
/* reference result for 4-bin block running-median computed in octave:
octave> m1 = median ( periodo(1:4) ); m2 = median ( periodo(2:5) );
octave> rngmed = [ m1, m1, m1, m2, m2 ];
octave> printf ("rngmedREF4[] = { %.16g, %.16g, %.16g, %.16g, %.16g };\n", rngmed );
rngmedREF4[] = { 3.96013552804278e-42, 3.96013552804278e-42, 3.96013552804278e-42, 4.28600095173228e-42, 4.28600095173228e-42 };
*/
REAL8 rngmedREF4[] = { 3.96013552804278e-42, 3.96013552804278e-42, 3.96013552804278e-42, 4.28600095173228e-42, 4.28600095173228e-42 };
/* compute running median */
XLAL_CHECK ( XLALSFTtoRngmed ( &rngmed, mySFT, blockSize4 ) == XLAL_SUCCESS, XLAL_EFUNC, "XLALSFTtoRngmed() failed.");
/* get median->mean bias correction, needed for octave-reference results, to make
* them comparable to the bias-corrected results from LALSFTtoRngmed()
*/
REAL8 medianBias4 = XLALRngMedBias ( blockSize4 );
XLAL_CHECK ( xlalErrno == 0, XLAL_EFUNC, "XLALRngMedBias() failed.");
printf ("%4s %22s %22s %8s <%g\n", "Bin", "rngmed(LAL)", "rngmed(Octave)", "relError", tol);
for (iBin=0; iBin < numBins; iBin ++ )
{
REAL8 rngmedVAL = rngmed.data->data[iBin];
REAL8 rngmedREF = rngmedREF4[iBin] / medianBias4; // apply median-bias correction
REAL8 relErr = REL_ERR ( rngmedREF, rngmedVAL );
if ( relErr > tol ) {
pass = 0;
passStr = "fail";
} else {
passStr = "OK.";
}
printf ("%4d %22.16g %22.16g %8.1g %s\n", iBin, rngmedVAL, rngmedREF, relErr, passStr );
} /* for iBin < numBins */
/* free memory */
XLALDestroyREAL8Vector ( rngmed.data );
XLALDestroySFT ( mySFT );
LALCheckMemoryLeaks();
if ( !pass )
{
printf ("Test failed! Difference exceeded tolerance.\n");
return XLAL_EFAILED;
}
else
{
printf ("Test passed.\n");
return XLAL_SUCCESS;
}
} /* main() */
/**
* Unit-Test for function XLALSFTVectorToLFT().
* Generates random data (timeseries + corresponding SFTs),
* then feeds the SFTs into XLALSFTVectorToLFT()
* and checks correctness of output Fourier transform by
* comparing to FT of original real-valued timeseries.
*
* \note This indirectly also checks XLALSFTVectorToCOMPLEX8TimeSeries()
* which is used by XLALSFTVectorToLFT().
*
* returns XLAL_SUCCESS on success, XLAL-error otherwise
*/
int
test_XLALSFTVectorToLFT ( void )
{
// ----- generate real-valued random timeseries and corresponding SFTs
REAL4TimeSeries *tsR4 = NULL;
SFTVector *sfts0 = NULL;
XLAL_CHECK ( XLALgenerateRandomData ( &tsR4, &sfts0 ) == XLAL_SUCCESS, XLAL_EFUNC );
UINT4 numSamplesR4 = tsR4->data->length;
REAL8 dt_R4 = tsR4->deltaT;
REAL8 TspanR4 = numSamplesR4 * dt_R4;
// ----- consider only the frequency band [3Hz, 4Hz]
REAL8 out_fMin = 3;
REAL8 out_Band = 1;
SFTVector *sftsBand;
XLAL_CHECK ( (sftsBand = XLALExtractBandFromSFTVector ( sfts0, out_fMin, out_Band )) != NULL, XLAL_EFUNC );
XLALDestroySFTVector ( sfts0 );
// ----- 1) compute FFT on original REAL4 timeseries -----
REAL4FFTPlan *planR4;
XLAL_CHECK ( (planR4 = XLALCreateForwardREAL4FFTPlan ( numSamplesR4, 0 )) != NULL, XLAL_EFUNC );
SFTtype *lft0;
XLAL_CHECK ( (lft0 = XLALCreateSFT ( numSamplesR4/2+1 )) != NULL, XLAL_EFUNC );
XLAL_CHECK ( XLALREAL4ForwardFFT ( lft0->data, tsR4->data, planR4 ) == XLAL_SUCCESS, XLAL_EFUNC );
strcpy ( lft0->name, tsR4->name );
lft0->f0 = 0;
lft0->epoch = tsR4->epoch;
REAL8 dfLFT = 1.0 / TspanR4;
lft0->deltaF = dfLFT;
// ----- extract frequency band of interest
SFTtype *lftR4 = NULL;
XLAL_CHECK ( XLALExtractBandFromSFT ( &lftR4, lft0, out_fMin, out_Band ) == XLAL_SUCCESS, XLAL_EFUNC );
for ( UINT4 k=0; k < lftR4->data->length; k ++ ) {
lftR4->data->data[k] *= dt_R4;
}
// ----- 2) compute LFT directly from SFTs ----------
SFTtype *lftSFTs0;
XLAL_CHECK ( (lftSFTs0 = XLALSFTVectorToLFT ( sftsBand, 1 )) != NULL, XLAL_EFUNC );
XLALDestroySFTVector ( sftsBand );
// ----- re-extract frequency band of interest
SFTtype *lftSFTs = NULL;
XLAL_CHECK ( XLALExtractBandFromSFT ( &lftSFTs, lftSFTs0, out_fMin, out_Band ) == XLAL_SUCCESS, XLAL_EFUNC );
if ( lalDebugLevel & LALINFO )
{ // ----- write debug output
XLAL_CHECK ( XLALdumpREAL4TimeSeries ( "TS_R4.dat", tsR4 ) == XLAL_SUCCESS, XLAL_EFUNC );
XLAL_CHECK ( write_SFTdata ("LFT_R4T.dat", lftR4 ) == XLAL_SUCCESS, XLAL_EFUNC );
XLAL_CHECK ( write_SFTdata ("LFT_SFTs.dat", lftSFTs ) == XLAL_SUCCESS, XLAL_EFUNC );
} // end: debug output
// ========== compare resulting LFTs ==========
VectorComparison XLAL_INIT_DECL(tol0);
XLALPrintInfo ("Comparing LFT with itself: should give 0 for all measures\n");
XLAL_CHECK ( XLALCompareSFTs ( lftR4, lftR4, &tol0 ) == XLAL_SUCCESS, XLAL_EFUNC );
XLAL_CHECK ( XLALCompareSFTs ( lftSFTs, lftSFTs, &tol0 ) == XLAL_SUCCESS, XLAL_EFUNC );
VectorComparison XLAL_INIT_DECL(tol);
tol.relErr_L1 = 4e-2;
tol.relErr_L2 = 5e-2;
tol.angleV = 5e-2; // rad
tol.relErr_atMaxAbsx = 1.2e-2;
tol.relErr_atMaxAbsy = 1.2e-2;
XLALPrintInfo ("Comparing LFT from REAL4-timeseries, to LFT from heterodyned COMPLEX8-timeseries:\n");
XLAL_CHECK ( XLALCompareSFTs ( lftR4, lftSFTs, &tol ) == XLAL_SUCCESS, XLAL_EFUNC );
// ---------- free memory ----------
XLALDestroyREAL4TimeSeries ( tsR4 );
XLALDestroyREAL4FFTPlan ( planR4 );
XLALDestroySFT ( lft0 );
XLALDestroySFT ( lftR4 );
XLALDestroySFT ( lftSFTs );
XLALDestroySFT ( lftSFTs0 );
return XLAL_SUCCESS;
} // test_XLALSFTVectorToLFT()
/**
* Turn the given multi-IFO SFTvectors into one long Fourier transform (LFT) over the total observation time
*/
SFTtype *
XLALSFTVectorToLFT ( SFTVector *sfts, /**< input SFT vector (gets modified!) */
REAL8 upsampling /**< upsampling factor >= 1 */
)
{
XLAL_CHECK_NULL ( (sfts != NULL) && (sfts->length > 0), XLAL_EINVAL );
XLAL_CHECK_NULL ( upsampling >= 1, XLAL_EDOM, "Upsampling factor (%f) must be >= 1 \n", upsampling );
// ----- some useful SFT infos
SFTtype *firstSFT = &(sfts->data[0]);
UINT4 numBinsSFT = firstSFT->data->length;
REAL8 dfSFT = firstSFT->deltaF;
REAL8 Tsft = 1.0 / dfSFT;
REAL8 f0SFT = firstSFT->f0;
// ----- turn input SFTs into a complex (heterodyned) timeseries
COMPLEX8TimeSeries *lTS;
XLAL_CHECK_NULL ( (lTS = XLALSFTVectorToCOMPLEX8TimeSeries ( sfts )) != NULL, XLAL_EFUNC );
REAL8 dt = lTS->deltaT;
UINT4 numSamples0 = lTS->data->length;
REAL8 Tspan0 = numSamples0 * dt;
// ---------- determine time-span of upsampled time-series
/* NOTE: Tspan MUST be an integer multiple of Tsft,
* in order for the frequency bins of the final FFT
* to be commensurate with the SFT bins.
* This is required so that fHet is an exact
* frequency-bin in both cases
*/
UINT4 numSFTsFit = lround ( (Tspan0 * upsampling) / Tsft );
REAL8 Tspan = numSFTsFit * Tsft;
UINT4 numSamples = lround ( Tspan / dt );
// ----- enlarge TimeSeries container for zero-padding if neccessary
if ( numSamples > numSamples0 )
{
XLAL_CHECK_NULL ( (lTS->data->data = XLALRealloc ( lTS->data->data, numSamples * sizeof(lTS->data->data[0]) )) != NULL, XLAL_ENOMEM );
lTS->data->length = numSamples;
memset ( lTS->data->data + numSamples0, 0, (numSamples - numSamples0) * sizeof(lTS->data->data[0])); /* set all new time-samples to zero */
}
/* translate this back into fmin for the LFT (counting down from DC==fHet) */
/* fHet = DC of our internal DFTs */
UINT4 NnegSFT = NhalfNeg ( numBinsSFT );
REAL8 fHet = f0SFT + 1.0 * NnegSFT * dfSFT;
UINT4 NnegLFT = NhalfNeg ( numSamples );
REAL8 f0LFT = fHet - NnegLFT / Tspan;
// ----- prepare output LFT ----------
SFTtype *outputLFT;
XLAL_CHECK_NULL ( (outputLFT = XLALCreateSFT ( numSamples )) != NULL, XLAL_EFUNC );
// prepare LFT header
strcpy ( outputLFT->name, firstSFT->name );
strncat ( outputLFT->name, ":long Fourier transform", sizeof(outputLFT->name) - 1 - strlen(outputLFT->name));
outputLFT->epoch = firstSFT->epoch;
outputLFT->f0 = f0LFT;
outputLFT->deltaF = 1.0 / Tspan;
outputLFT->sampleUnits = firstSFT->sampleUnits;
// ---------- FFT the long timeseries ----------
COMPLEX8FFTPlan *LFTplan;
XLAL_CHECK_NULL ( (LFTplan = XLALCreateForwardCOMPLEX8FFTPlan( numSamples, 0 )) != NULL, XLAL_EFUNC );
XLAL_CHECK_NULL ( XLALCOMPLEX8VectorFFT( outputLFT->data, lTS->data, LFTplan ) == XLAL_SUCCESS, XLAL_EFUNC );
XLAL_CHECK_NULL ( XLALReorderFFTWtoSFT (outputLFT->data) == XLAL_SUCCESS, XLAL_EFUNC );
// apply proper normalization 'dt'
for ( UINT4 k = 0; k < outputLFT->data->length; k ++ ) {
outputLFT->data->data[k] *= dt;
}
/* cleanup memory */
XLALDestroyCOMPLEX8TimeSeries ( lTS );
XLALDestroyCOMPLEX8FFTPlan ( LFTplan );
return outputLFT;
} // XLALSFTVectorToLFT()
