Python FrequencySeries.chirp_length方法代码示例

# 需要导入模块: from pycbc.types import FrequencySeries [as 别名]
# 或者: from pycbc.types.FrequencySeries import chirp_length [as 别名]
def get_waveform_filter(out, template=None, **kwargs):
    """Return a frequency domain waveform filter for the specified approximant
    """
    n = len(out)

    input_params = props(template, **kwargs)

    if input_params['approximant'] in filter_approximants(_scheme.mgr.state):
        wav_gen = filter_wav[type(_scheme.mgr.state)]
        htilde = wav_gen[input_params['approximant']](out=out, **input_params)
        htilde.resize(n)
        htilde.chirp_length = get_waveform_filter_length_in_time(**input_params)
        htilde.length_in_time = htilde.chirp_length
        return htilde

    if input_params['approximant'] in fd_approximants(_scheme.mgr.state):
        wav_gen = fd_wav[type(_scheme.mgr.state)]
        hp, hc = wav_gen[input_params['approximant']](**input_params)
        hp.resize(n)
        out[0:len(hp)] = hp[:]
        hp = FrequencySeries(out, delta_f=hp.delta_f, copy=False)
        hp.chirp_length = get_waveform_filter_length_in_time(**input_params)
        hp.length_in_time = hp.chirp_length
        return hp

    elif input_params['approximant'] in td_approximants(_scheme.mgr.state):
        # N: number of time samples required
        N = (n-1)*2
        delta_f = 1.0 / (N * input_params['delta_t'])
        wav_gen = td_wav[type(_scheme.mgr.state)]
        hp, hc = wav_gen[input_params['approximant']](**input_params)
        # taper the time series hp if required
        if ('taper' in input_params.keys() and \
            input_params['taper'] is not None):
            hp = wfutils.taper_timeseries(hp, input_params['taper'],
                                          return_lal=False)
        # total duration of the waveform
        tmplt_length = len(hp) * hp.delta_t
        # for IMR templates the zero of time is at max amplitude (merger)
        # thus the start time is minus the duration of the template from
        # lower frequency cutoff to merger, i.e. minus the 'chirp time'
        tChirp = - float( hp.start_time )  # conversion from LIGOTimeGPS
        hp.resize(N)
        k_zero = int(hp.start_time / hp.delta_t)
        hp.roll(k_zero)
        htilde = FrequencySeries(out, delta_f=delta_f, copy=False)
        fft(hp.astype(real_same_precision_as(htilde)), htilde)
        htilde.length_in_time = tmplt_length
        htilde.chirp_length = tChirp
        return htilde

    else:
        raise ValueError("Approximant %s not available" %
                            (input_params['approximant']))

# 需要导入模块: from pycbc.types import FrequencySeries [as 别名]
# 或者: from pycbc.types.FrequencySeries import chirp_length [as 别名]
def td_waveform_to_fd_waveform(waveform, out=None, length=None,
                               buffer_length=100):
    """ Convert a time domain into a frequency domain waveform by FFT.
        As a waveform is assumed to "wrap" in the time domain one must be
        careful to ensure the waveform goes to 0 at both "boundaries". To
        ensure this is done correctly the waveform must have the epoch set such
        the merger time is at t=0 and the length of the waveform should be
        shorter than the desired length of the FrequencySeries (times 2 - 1)
        so that zeroes can be suitably pre- and post-pended before FFTing.
        If given, out is a memory array to be used as the output of the FFT.
        If not given memory is allocated internally.
        If present the length of the returned FrequencySeries is determined
        from the length out. If out is not given the length can be provided
        expicitly, or it will be chosen as the nearest power of 2. If choosing
        length explicitly the waveform length + buffer_length is used when
        choosing the nearest binary number so that some zero padding is always
        added.
    """
    # Figure out lengths and set out if needed
    if out is None:
        if length is None:
            N = pnutils.nearest_larger_binary_number(len(waveform) + \
                                                     buffer_length)
            n = int(N//2) + 1
        else:
            n = length
            N = (n-1)*2
        out = zeros(n, dtype=complex_same_precision_as(waveform))
    else:
        n = len(out)
        N = (n-1)*2
    delta_f =  1. / (N * waveform.delta_t)

    # total duration of the waveform
    tmplt_length = len(waveform) * waveform.delta_t
    if len(waveform) > N:
        err_msg = "The time domain template is longer than the intended "
        err_msg += "duration in the frequency domain. This situation is "
        err_msg += "not supported in this function. Please shorten the "
        err_msg += "waveform appropriately before calling this function or "
        err_msg += "increase the allowed waveform length. "
        err_msg += "Waveform length (in samples): {}".format(len(waveform))
        err_msg += ". Intended length: {}.".format(N)
        raise ValueError(err_msg)
    # for IMR templates the zero of time is at max amplitude (merger)
    # thus the start time is minus the duration of the template from
    # lower frequency cutoff to merger, i.e. minus the 'chirp time'
    tChirp = - float( waveform.start_time )  # conversion from LIGOTimeGPS
    waveform.resize(N)
    k_zero = int(waveform.start_time / waveform.delta_t)
    waveform.roll(k_zero)
    htilde = FrequencySeries(out, delta_f=delta_f, copy=False)
    fft(waveform.astype(real_same_precision_as(htilde)), htilde)
    htilde.length_in_time = tmplt_length
    htilde.chirp_length = tChirp
    return htilde

# 需要导入模块: from pycbc.types import FrequencySeries [as 别名]
# 或者: from pycbc.types.FrequencySeries import chirp_length [as 别名]
def get_waveform_filter(out, template=None, **kwargs):
    """Return a frequency domain waveform filter for the specified approximant
    """
    n = len(out)

    input_params = props(template, **kwargs)

    if input_params['approximant'] in filter_approximants(_scheme.mgr.state):
        wav_gen = filter_wav[type(_scheme.mgr.state)]
        htilde = wav_gen[input_params['approximant']](out=out, **input_params)
        htilde.resize(n)
        htilde.chirp_length = get_waveform_filter_length_in_time(**input_params)
        htilde.length_in_time = htilde.chirp_length
        return htilde

    if input_params['approximant'] in fd_approximants(_scheme.mgr.state):
        wav_gen = fd_wav[type(_scheme.mgr.state)]
        hp, hc = wav_gen[input_params['approximant']](**input_params)
        hp.resize(n)
        out[0:len(hp)] = hp[:]
        hp = FrequencySeries(out, delta_f=hp.delta_f, copy=False)
        hp.chirp_length = get_waveform_filter_length_in_time(**input_params)
        hp.length_in_time = hp.chirp_length
        return hp

    elif input_params['approximant'] in td_approximants(_scheme.mgr.state):
        # N: number of time samples required
        N = (n-1)*2
        delta_f = 1.0 / (N * input_params['delta_t'])
        wav_gen = td_wav[type(_scheme.mgr.state)]
        hp, hc = wav_gen[input_params['approximant']](**input_params)
        # taper the time series hp if required
        if ('taper' in input_params.keys() and \
            input_params['taper'] is not None):
            hp = wfutils.taper_timeseries(hp, input_params['taper'],
                                          return_lal=False)
        return td_waveform_to_fd_waveform(hp, out=out)

    else:
        raise ValueError("Approximant %s not available" %
                            (input_params['approximant']))

# 需要导入模块: from pycbc.types import FrequencySeries [as 别名]
# 或者: from pycbc.types.FrequencySeries import chirp_length [as 别名]
def get_two_pol_waveform_filter(outplus, outcross, template, **kwargs):
    """Return a frequency domain waveform filter for the specified approximant.
    Unlike get_waveform_filter this function returns both h_plus and h_cross
    components of the waveform, which are needed for searches where h_plus
    and h_cross are not related by a simple phase shift.
    """
    n = len(outplus)

    # If we don't have an inclination column alpha3 might be used
    if not hasattr(template, 'inclination') and 'inclination' not in kwargs:
        if hasattr(template, 'alpha3'):
            kwargs['inclination'] = template.alpha3

    input_params = props(template, **kwargs)

    if input_params['approximant'] in fd_approximants(_scheme.mgr.state):
        wav_gen = fd_wav[type(_scheme.mgr.state)]
        hp, hc = wav_gen[input_params['approximant']](**input_params)
        hp.resize(n)
        hc.resize(n)
        outplus[0:len(hp)] = hp[:]
        hp = FrequencySeries(outplus, delta_f=hp.delta_f, copy=False)
        outcross[0:len(hc)] = hc[:]
        hc = FrequencySeries(outcross, delta_f=hc.delta_f, copy=False)
        hp.chirp_length = get_waveform_filter_length_in_time(**input_params)
        hp.length_in_time = hp.chirp_length
        hc.chirp_length = hp.chirp_length
        hc.length_in_time = hp.length_in_time
        return hp, hc
    elif input_params['approximant'] in td_approximants(_scheme.mgr.state):
        # N: number of time samples required
        N = (n-1)*2
        delta_f = 1.0 / (N * input_params['delta_t'])
        wav_gen = td_wav[type(_scheme.mgr.state)]
        hp, hc = wav_gen[input_params['approximant']](**input_params)
        # taper the time series hp if required
        if 'taper' in input_params.keys() and \
                input_params['taper'] is not None:
            hp = wfutils.taper_timeseries(hp, input_params['taper'],
                                          return_lal=False)
            hc = wfutils.taper_timeseries(hc, input_params['taper'],
                                          return_lal=False)
        # total duration of the waveform
        tmplt_length = len(hp) * hp.delta_t
        # for IMR templates the zero of time is at max amplitude (merger)
        # thus the start time is minus the duration of the template from
        # lower frequency cutoff to merger, i.e. minus the 'chirp time'
        tChirp = - float( hp.start_time )  # conversion from LIGOTimeGPS
        hp.resize(N)
        hc.resize(N)
        k_zero = int(hp.start_time / hp.delta_t)
        hp.roll(k_zero)
        hc.roll(k_zero)
        hp_tilde = FrequencySeries(outplus, delta_f=delta_f, copy=False)
        hc_tilde = FrequencySeries(outcross, delta_f=delta_f, copy=False)
        fft(hp.astype(real_same_precision_as(hp_tilde)), hp_tilde)
        fft(hc.astype(real_same_precision_as(hc_tilde)), hc_tilde)
        hp_tilde.length_in_time = tmplt_length
        hp_tilde.chirp_length = tChirp
        hc_tilde.length_in_time = tmplt_length
        hc_tilde.chirp_length = tChirp
        return hp_tilde, hc_tilde
    else:
        raise ValueError("Approximant %s not available" %
                            (input_params['approximant']))