Beispiel #1
0
def damped_chirp_tmplt(det_data, int_params, ext_params):
    """
    Build a template for the detector in det_data from the intrinsic and
    extrinsic parameteres in int_params and ext_params
    """

    #
    # Compute polarisations for damped chirp
    #

    #   _, hp = damped_chirp(int_params.tmplt_len,
    #           int_params.Amp, int_params.f0, int_params.tau, int_params.df)
    #
    #   _, hc = damped_chirp(int_params.tmplt_len,
    #           int_params.Amp, int_params.f0, int_params.tau, int_params.df,
    #           phi0=90.0)

    # Get the epoch for the start of the time series
    epoch = ext_params.geocent_peak_time  # - \
    #np.argmax(hp)*det_data.td_response.delta_t
    # XXX: why don't we need to subtract this bit...?

    Q = 2.0 * np.pi * int_params.tau * int_params.f0

    hp, hc = lalsim.SimBurstChirplet(Q, int_params.f0, int_params.df,
                                     int_params.Amp, 0, 0, 1.0 / 16384)
    hp.data.data[0:hp.data.length / 2] = 0.0
    hc.data.data[0:hp.data.length / 2] = 0.0

    hplus = lal.CreateREAL8TimeSeries('hplus', epoch, 0,
                                      det_data.td_noise.delta_t,
                                      lal.StrainUnit, hp.data.length)
    hplus.data.data = np.copy(hp.data.data)
    del hp

    hcross = lal.CreateREAL8TimeSeries('hcross', epoch, 0,
                                       det_data.td_noise.delta_t,
                                       lal.StrainUnit, hc.data.length)
    hcross.data.data = np.copy(hc.data.data)
    del hc

    #   try:
    #       time_delay = lal.TimeDelayFromEarthCenter(det_data.det_site.location,
    #               ext_params.ra, ext_params.dec, ext_params.geocent_peak_time)
    #   except RuntimeError:
    #       time_delay = lal.TimeDelayFromEarthCenter(det_data.det_site.location,
    #               ext_params.ra, ext_params.dec, -1e4)

    # --- Put the polarisations into LAL TimeSeries
    #   hplus = lal.CreateREAL8TimeSeries('hplus', epoch, 0,
    #           det_data.td_noise.delta_t, lal.StrainUnit, len(hp))
    #   hplus.data.data=np.copy(hp)
    #   del hp
    #
    #   hcross = lal.CreateREAL8TimeSeries('hcross', epoch, 0,
    #           det_data.td_noise.delta_t, lal.StrainUnit, len(hc))
    #   hcross.data.data=np.copy(hc)
    #   del hc

    #
    # Project polarisations down to detector
    #
    tmplt = lalsim.SimDetectorStrainREAL8TimeSeries(hplus, hcross,
                                                    ext_params.ra,
                                                    ext_params.dec,
                                                    ext_params.polarization,
                                                    det_data.det_site)
    del hplus, hcross

    # Scale for distance (waveforms extracted at 20 Mpc)
    tmplt.data.data *= 20.0 / ext_params.distance

    #
    # Finally make this the same size as the data (useful for fitting)
    #
    #lal.ResizeREAL8TimeSeries(tmplt, 0, len(det_data.td_response.data))
    no_noise = lal.CreateREAL8TimeSeries(
        'blah', det_data.td_noise.start_time, 0, det_data.td_noise.delta_t,
        lal.StrainUnit,
        int(det_data.td_noise.duration / det_data.td_noise.delta_t))
    no_noise.data.data = np.zeros(
        int(det_data.td_noise.duration / det_data.td_noise.delta_t))

    tmplt = lal.AddREAL8TimeSeries(no_noise, tmplt)

    return pycbc.types.timeseries.TimeSeries(\
            initial_array=np.copy(tmplt.data.data), delta_t=tmplt.deltaT,
            epoch=tmplt.epoch)
Beispiel #2
0
    def real_hoft(self, Fp=None, Fc=None):
        """
        Returns the real-valued h(t) that would be produced in a single instrument.
        Translates epoch as needed.
        Based on 'hoft' in lalsimutils.py
        """
        # Create complex timessereis
        htC = self.complex_hoft(
            force_T=1. / self.P.deltaF, deltaT=self.P.deltaT
        )  # note P.tref is NOT used in the low-level code
        TDlen = htC.data.length
        if rosDebug:
            print("Size sanity check ", TDlen,
                  1 / (self.P.deltaF * self.P.deltaT))
            print(" Raw complex magnitude , ", np.max(htC.data.data))

        # Create working buffers to extract data from it -- wasteful.
        hp = lal.CreateREAL8TimeSeries("h(t)", htC.epoch, 0., self.P.deltaT,
                                       lalsimutils.lsu_DimensionlessUnit,
                                       TDlen)
        hc = lal.CreateREAL8TimeSeries("h(t)", htC.epoch, 0., self.P.deltaT,
                                       lalsimutils.lsu_DimensionlessUnit,
                                       TDlen)
        hT = lal.CreateREAL8TimeSeries("h(t)", htC.epoch, 0., self.P.deltaT,
                                       lalsimutils.lsu_DimensionlessUnit,
                                       TDlen)
        # Copy data components over
        hp.data.data = np.real(htC.data.data)
        hc.data.data = np.imag(htC.data.data)
        # transform as in lalsimutils.hoft
        if Fp != None and Fc != None:
            hp.data.data *= Fp
            hc.data.data *= Fc
            hp = lal.AddREAL8TimeSeries(hp, hc)
            hoft = hp
        elif self.P.radec == False:
            fp = lalsimutils.Fplus(self.P.theta, self.P.phi, self.P.psi)
            fc = lalsimutils.Fcross(self.P.theta, self.P.phi, self.P.psi)
            hp.data.data *= fp
            hc.data.data *= fc
            hp.data.data = lal.AddREAL8TimeSeries(hp, hc)
            hoft = hp
        else:
            # Note epoch must be applied FIRST, to make sure the correct event time is being used to construct the modulation functions
            hp.epoch = hp.epoch + self.P.tref
            hc.epoch = hc.epoch + self.P.tref
            if rosDebug:
                print(" Real h(t) before detector weighting, ",
                      np.max(hp.data.data), np.max(hc.data.data))
            hoft = lalsim.SimDetectorStrainREAL8TimeSeries(
                hp,
                hc,  # beware, this MAY alter the series length??
                self.P.phi,
                self.P.theta,
                self.P.psi,
                lalsim.DetectorPrefixToLALDetector(str(self.P.detector)))
            hoft = lal.CutREAL8TimeSeries(
                hoft, 0, hp.data.length)  # force same length as before??
            if rosDebug:
                print("Size before and after detector weighting ",
                      hp.data.length, hoft.data.length)
        if rosDebug:
            print(" Real h_{IFO}(t) generated, pre-taper : max strain =",
                  np.max(hoft.data.data))
        if self.P.taper != lalsimutils.lsu_TAPER_NONE:  # Taper if requested
            lalsim.SimInspiralREAL8WaveTaper(hoft.data, self.P.taper)
        if self.P.deltaF is not None:
            TDlen = int(1. / self.P.deltaF * 1. / self.P.deltaT)
            print("Size sanity check 2 ",
                  int(1. / self.P.deltaF * 1. / self.P.deltaT),
                  hoft.data.length)
            assert TDlen >= hoft.data.length
            npts = hoft.data.length
            hoft = lal.ResizeREAL8TimeSeries(hoft, 0, TDlen)
            # Zero out the last few data elements -- NOT always reliable for all architectures; SHOULD NOT BE NECESSARY
            hoft.data.data[npts:TDlen] = 0

        if rosDebug:
            print(" Real h_{IFO}(t) generated : max strain =",
                  np.max(hoft.data.data))
        return hoft
Beispiel #3
0
    def add_signal_to_noise(self):
        """
        Sum the noise and the signal to get the 'measured' strain in the
        detector
        """

        # noise
        noise = lal.CreateREAL8TimeSeries(
            'blah', self.epoch, 0, self.td_noise.delta_t, lal.StrainUnit,
            int(self.td_noise.duration / self.td_noise.delta_t))
        noise.data.data = self.td_noise.data

        # signal
        signal = lal.CreateREAL8TimeSeries(
            'blah', self.ext_params.geocent_peak_time, 0,
            self.td_signal.delta_t, lal.StrainUnit,
            int(self.td_signal.duration / self.td_signal.delta_t))
        signal.data.data = self.td_signal.data

        win = lal.CreateTukeyREAL8Window(len(signal.data.data), 0.1)
        win.data.data[len(signal.data.data):] = 1.0
        #signal.data.data *= win.data.data

        # --- Scale to a target snr
        print '---'
        if self.target_snr is not None:

            tmp_sig = pycbc.types.TimeSeries(signal.data.data,
                                             delta_t=self.td_signal.delta_t)

            current_snr = pycbc.filter.sigma(tmp_sig,
                                             psd=self.psd,
                                             low_frequency_cutoff=self.f_low,
                                             high_frequency_cutoff=0.5 /
                                             self.delta_t)

            signal.data.data *= self.target_snr / current_snr
        # ----

        # sum
        noise_plus_signal = lal.AddREAL8TimeSeries(noise, signal)

        self.td_response = \
                pycbc.types.timeseries.TimeSeries(\
                initial_array=np.copy(noise_plus_signal.data.data),
                        delta_t=noise_plus_signal.deltaT,
                        epoch=noise_plus_signal.epoch)

        # Finally, zero-pad the signal vector to have the same length as the actual data
        # vector
        no_noise = lal.CreateREAL8TimeSeries(
            'blah', self.epoch, 0, self.td_noise.delta_t, lal.StrainUnit,
            int(self.td_noise.duration / self.td_noise.delta_t))

        no_noise.data.data = np.zeros(\
                int(self.td_noise.duration / self.td_noise.delta_t))

        signal = lal.AddREAL8TimeSeries(no_noise, signal)

        self.td_signal = \
                pycbc.types.timeseries.TimeSeries(initial_array=np.copy(signal.data.data),
                        delta_t=signal.deltaT, epoch=noise_plus_signal.epoch)

        del noise, signal, noise_plus_signal