# Copyright (C) 2018 Charlie Hoy, Collin Capano
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
# Free Software Foundation; either version 3 of the License, or (at your
# option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
# Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
"""This module provides model classes that assume the noise is Gaussian and
allows for the likelihood to be marginalized over phase and/or time and/or
distance.
"""
import itertools
import logging
import numpy
from scipy import special
from pycbc.waveform import generator
from pycbc.waveform import (NoWaveformError, FailedWaveformError)
from pycbc.detector import Detector
from .gaussian_noise import (BaseGaussianNoise,
create_waveform_generator,
GaussianNoise)
from .tools import marginalize_likelihood, DistMarg
[docs]
class MarginalizedPhaseGaussianNoise(GaussianNoise):
r"""The likelihood is analytically marginalized over phase.
This class can be used with signal models that can be written as:
.. math::
\tilde{h}(f; \Theta, \phi) = A(f; \Theta)e^{i\Psi(f; \Theta) + i \phi},
where :math:`\phi` is an arbitrary phase constant. This phase constant
can be analytically marginalized over with a uniform prior as follows:
assuming the noise is stationary and Gaussian (see `GaussianNoise`
for details), the posterior is:
.. math::
p(\Theta,\phi|d)
&\propto p(\Theta)p(\phi)p(d|\Theta,\phi) \\
&\propto p(\Theta)\frac{1}{2\pi}\exp\left[
-\frac{1}{2}\sum_{i}^{N_D} \left<
h_i(\Theta,\phi) - d_i, h_i(\Theta,\phi) - d_i
\right>\right].
Here, the sum is over the number of detectors :math:`N_D`, :math:`d_i`
and :math:`h_i` are the data and signal in detector :math:`i`,
respectively, and we have assumed a uniform prior on :math:`\phi \in [0,
2\pi)`. With the form of the signal model given above, the inner product
in the exponent can be written as:
.. math::
-\frac{1}{2}\left<h_i - d_i, h_i- d_i\right>
&= \left<h_i, d_i\right> -
\frac{1}{2}\left<h_i, h_i\right> -
\frac{1}{2}\left<d_i, d_i\right> \\
&= \Re\left\{O(h^0_i, d_i)e^{-i\phi}\right\} -
\frac{1}{2}\left<h^0_i, h^0_i\right> -
\frac{1}{2}\left<d_i, d_i\right>,
where:
.. math::
h_i^0 &\equiv \tilde{h}_i(f; \Theta, \phi=0); \\
O(h^0_i, d_i) &\equiv 4 \int_0^\infty
\frac{\tilde{h}_i^*(f; \Theta,0)\tilde{d}_i(f)}{S_n(f)}\mathrm{d}f.
Gathering all of the terms that are not dependent on :math:`\phi` together:
.. math::
\alpha(\Theta, d) \equiv \exp\left[-\frac{1}{2}\sum_i
\left<h^0_i, h^0_i\right> + \left<d_i, d_i\right>\right],
we can marginalize the posterior over :math:`\phi`:
.. math::
p(\Theta|d)
&\propto p(\Theta)\alpha(\Theta,d)\frac{1}{2\pi}
\int_{0}^{2\pi}\exp\left[\Re \left\{
e^{-i\phi} \sum_i O(h^0_i, d_i)
\right\}\right]\mathrm{d}\phi \\
&\propto p(\Theta)\alpha(\Theta, d)\frac{1}{2\pi}
\int_{0}^{2\pi}\exp\left[
x(\Theta,d)\cos(\phi) + y(\Theta, d)\sin(\phi)
\right]\mathrm{d}\phi.
The integral in the last line is equal to :math:`2\pi I_0(\sqrt{x^2+y^2})`,
where :math:`I_0` is the modified Bessel function of the first kind. Thus
the marginalized posterior is:
.. math::
p(\Theta|d) \propto
I_0\left(\left|\sum_i O(h^0_i, d_i)\right|\right)
p(\Theta)\exp\left[\frac{1}{2}\sum_i\left( \left<h^0_i, h^0_i\right> -
\left<d_i, d_i\right> \right)\right]
"""
name = 'marginalized_phase'
def __init__(self, variable_params, data, low_frequency_cutoff, psds=None,
high_frequency_cutoff=None, normalize=False,
static_params=None, **kwargs):
# set up the boiler-plate attributes
super(MarginalizedPhaseGaussianNoise, self).__init__(
variable_params, data, low_frequency_cutoff, psds=psds,
high_frequency_cutoff=high_frequency_cutoff, normalize=normalize,
static_params=static_params, **kwargs)
@property
def _extra_stats(self):
"""Adds ``loglr``, plus ``cplx_loglr`` and ``optimal_snrsq`` in each
detector."""
return ['loglr', 'maxl_phase'] + \
['{}_optimal_snrsq'.format(det) for det in self._data]
def _nowaveform_loglr(self):
"""Convenience function to set loglr values if no waveform generated.
"""
setattr(self._current_stats, 'loglikelihood', -numpy.inf)
# maxl phase doesn't exist, so set it to nan
setattr(self._current_stats, 'maxl_phase', numpy.nan)
for det in self._data:
# snr can't be < 0 by definition, so return 0
setattr(self._current_stats, '{}_optimal_snrsq'.format(det), 0.)
return -numpy.inf
def _loglr(self):
r"""Computes the log likelihood ratio,
.. math::
\log \mathcal{L}(\Theta) =
I_0 \left(\left|\sum_i O(h^0_i, d_i)\right|\right) -
\frac{1}{2}\left<h^0_i, h^0_i\right>,
at the current point in parameter space :math:`\Theta`.
Returns
-------
float
The value of the log likelihood ratio evaluated at the given point.
"""
params = self.current_params
try:
if self.all_ifodata_same_rate_length:
wfs = self.waveform_generator.generate(**params)
else:
wfs = {}
for det in self.data:
wfs.update(self.waveform_generator[det].generate(**params))
except NoWaveformError:
return self._nowaveform_loglr()
except FailedWaveformError as e:
if self.ignore_failed_waveforms:
return self._nowaveform_loglr()
else:
raise e
hh = 0.
hd = 0j
for det, h in wfs.items():
# the kmax of the waveforms may be different than internal kmax
kmax = min(len(h), self._kmax[det])
if self._kmin[det] >= kmax:
# if the waveform terminates before the filtering low frequency
# cutoff, then the loglr is just 0 for this detector
hh_i = 0.
hd_i = 0j
else:
# whiten the waveform
h[self._kmin[det]:kmax] *= \
self._weight[det][self._kmin[det]:kmax]
# calculate inner products
hh_i = h[self._kmin[det]:kmax].inner(
h[self._kmin[det]:kmax]).real
hd_i = h[self._kmin[det]:kmax].inner(
self._whitened_data[det][self._kmin[det]:kmax])
# store
setattr(self._current_stats, '{}_optimal_snrsq'.format(det), hh_i)
hh += hh_i
hd += hd_i
self._current_stats.maxl_phase = numpy.angle(hd)
return marginalize_likelihood(hd, hh, phase=True)
[docs]
class MarginalizedTime(DistMarg, BaseGaussianNoise):
r""" This likelihood numerically marginalizes over time
This likelihood is optimized for marginalizing over time, but can also
handle marginalization over polarization, phase (where appropriate),
and sky location. The time series is interpolated using a
quadratic apparoximation for sub-sample times.
"""
name = 'marginalized_time'
def __init__(self, variable_params,
data, low_frequency_cutoff, psds=None,
high_frequency_cutoff=None, normalize=False,
sample_rate=None,
**kwargs):
# the flag used in `_loglr`
self.return_sh_hh = False
self.sample_rate = float(sample_rate)
self.kwargs = kwargs
variable_params, kwargs = self.setup_marginalization(
variable_params,
**kwargs)
# set up the boiler-plate attributes
super(MarginalizedTime, self).__init__(
variable_params, data, low_frequency_cutoff, psds=psds,
high_frequency_cutoff=high_frequency_cutoff, normalize=normalize,
**kwargs)
# Determine if all data have the same sampling rate and segment length
if self.all_ifodata_same_rate_length:
# create a waveform generator for all ifos
self.waveform_generator = create_waveform_generator(
self.variable_params, self.data,
waveform_transforms=self.waveform_transforms,
recalibration=self.recalibration,
generator_class=generator.FDomainDetFrameTwoPolNoRespGenerator,
gates=self.gates, **kwargs['static_params'])
else:
# create a waveform generator for each ifo respectively
self.waveform_generator = {}
for det in self.data:
self.waveform_generator[det] = create_waveform_generator(
self.variable_params, {det: self.data[det]},
waveform_transforms=self.waveform_transforms,
recalibration=self.recalibration,
generator_class=generator.FDomainDetFrameTwoPolNoRespGenerator,
gates=self.gates, **kwargs['static_params'])
self.dets = {}
if sample_rate is not None:
for ifo in self.data:
if self.sample_rate < self.data[ifo].sample_rate:
raise ValueError("Model sample rate was set less than the"
" data. ")
logging.info("Using %s sample rate for marginalization",
sample_rate)
def _nowaveform_loglr(self):
"""Convenience function to set loglr values if no waveform generated.
"""
return -numpy.inf
def _loglr(self):
r"""Computes the log likelihood ratio,
or inner product <s|h> and <h|h> if `self.return_sh_hh` is True.
.. math::
\log \mathcal{L}(\Theta) = \sum_i
\left<h_i(\Theta)|d_i\right> -
\frac{1}{2}\left<h_i(\Theta)|h_i(\Theta)\right>,
at the current parameter values :math:`\Theta`.
Returns
-------
float
The value of the log likelihood ratio.
"""
from pycbc.filter import matched_filter_core
params = self.current_params
try:
if self.all_ifodata_same_rate_length:
wfs = self.waveform_generator.generate(**params)
else:
wfs = {}
for det in self.data:
wfs.update(self.waveform_generator[det].generate(**params))
except NoWaveformError:
return self._nowaveform_loglr()
except FailedWaveformError as e:
if self.ignore_failed_waveforms:
return self._nowaveform_loglr()
else:
raise e
sh_total = hh_total = 0.
snr_estimate = {}
cplx_hpd = {}
cplx_hcd = {}
hphp = {}
hchc = {}
hphc = {}
for det, (hp, hc) in wfs.items():
# the kmax of the waveforms may be different than internal kmax
kmax = min(max(len(hp), len(hc)), self._kmax[det])
slc = slice(self._kmin[det], kmax)
# whiten both polarizations
hp[self._kmin[det]:kmax] *= self._weight[det][slc]
hc[self._kmin[det]:kmax] *= self._weight[det][slc]
# Use a higher sample rate if requested
if self.sample_rate is not None:
tlen = int(round(self.sample_rate *
self.whitened_data[det].duration))
flen = tlen // 2 + 1
hp.resize(flen)
hc.resize(flen)
self._whitened_data[det].resize(flen)
cplx_hpd[det], _, _ = matched_filter_core(
hp,
self._whitened_data[det],
low_frequency_cutoff=self._f_lower[det],
high_frequency_cutoff=self._f_upper[det],
h_norm=1)
cplx_hcd[det], _, _ = matched_filter_core(
hc,
self._whitened_data[det],
low_frequency_cutoff=self._f_lower[det],
high_frequency_cutoff=self._f_upper[det],
h_norm=1)
hphp[det] = hp[slc].inner(hp[slc]).real
hchc[det] = hc[slc].inner(hc[slc]).real
hphc[det] = hp[slc].inner(hc[slc]).real
snr_proxy = ((cplx_hpd[det] / hphp[det] ** 0.5).squared_norm() +
(cplx_hcd[det] / hchc[det] ** 0.5).squared_norm())
snr_estimate[det] = (0.5 * snr_proxy) ** 0.5
self.draw_ifos(snr_estimate, log=False, **self.kwargs)
self.snr_draw(snrs=snr_estimate)
for det in wfs:
if det not in self.dets:
self.dets[det] = Detector(det)
if self.precalc_antenna_factors:
fp, fc, dt = self.get_precalc_antenna_factors(det)
else:
fp, fc = self.dets[det].antenna_pattern(
params['ra'],
params['dec'],
params['polarization'],
params['tc'])
dt = self.dets[det].time_delay_from_earth_center(params['ra'],
params['dec'],
params['tc'])
dtc = params['tc'] + dt
cplx_hd = fp * cplx_hpd[det].at_time(dtc,
interpolate='quadratic')
cplx_hd += fc * cplx_hcd[det].at_time(dtc,
interpolate='quadratic')
hh = (fp * fp * hphp[det] +
fc * fc * hchc[det] +
2.0 * fp * fc * hphc[det])
sh_total += cplx_hd
hh_total += hh
loglr = self.marginalize_loglr(sh_total, hh_total)
if self.return_sh_hh:
results = (sh_total, hh_total)
else:
results = loglr
return results
[docs]
class MarginalizedPolarization(DistMarg, BaseGaussianNoise):
r""" This likelihood numerically marginalizes over polarization angle
This class implements the Gaussian likelihood with an explicit numerical
marginalization over polarization angle. This is accomplished using
a fixed set of integration points distribution uniformation between
0 and 2pi. By default, 1000 integration points are used.
The 'polarization_samples' argument can be passed to set an alternate
number of integration points.
"""
name = 'marginalized_polarization'
def __init__(self, variable_params, data, low_frequency_cutoff, psds=None,
high_frequency_cutoff=None, normalize=False,
polarization_samples=1000,
**kwargs):
variable_params, kwargs = self.setup_marginalization(
variable_params,
polarization_samples=polarization_samples,
**kwargs)
# set up the boiler-plate attributes
super(MarginalizedPolarization, self).__init__(
variable_params, data, low_frequency_cutoff, psds=psds,
high_frequency_cutoff=high_frequency_cutoff, normalize=normalize,
**kwargs)
# Determine if all data have the same sampling rate and segment length
if self.all_ifodata_same_rate_length:
# create a waveform generator for all ifos
self.waveform_generator = create_waveform_generator(
self.variable_params, self.data,
waveform_transforms=self.waveform_transforms,
recalibration=self.recalibration,
generator_class=generator.FDomainDetFrameTwoPolGenerator,
gates=self.gates, **kwargs['static_params'])
else:
# create a waveform generator for each ifo respectively
self.waveform_generator = {}
for det in self.data:
self.waveform_generator[det] = create_waveform_generator(
self.variable_params, {det: self.data[det]},
waveform_transforms=self.waveform_transforms,
recalibration=self.recalibration,
generator_class=generator.FDomainDetFrameTwoPolGenerator,
gates=self.gates, **kwargs['static_params'])
self.dets = {}
@property
def _extra_stats(self):
"""Adds ``loglr``, ``maxl_polarization``, and the ``optimal_snrsq`` in
each detector.
"""
return ['loglr', 'maxl_polarization', 'maxl_loglr'] + \
['{}_optimal_snrsq'.format(det) for det in self._data]
def _nowaveform_loglr(self):
"""Convenience function to set loglr values if no waveform generated.
"""
setattr(self._current_stats, 'loglr', -numpy.inf)
# maxl phase doesn't exist, so set it to nan
setattr(self._current_stats, 'maxl_polarization', numpy.nan)
for det in self._data:
# snr can't be < 0 by definition, so return 0
setattr(self._current_stats, '{}_optimal_snrsq'.format(det), 0.)
return -numpy.inf
def _loglr(self):
r"""Computes the log likelihood ratio,
.. math::
\log \mathcal{L}(\Theta) = \sum_i
\left<h_i(\Theta)|d_i\right> -
\frac{1}{2}\left<h_i(\Theta)|h_i(\Theta)\right>,
at the current parameter values :math:`\Theta`.
Returns
-------
float
The value of the log likelihood ratio.
"""
params = self.current_params
try:
if self.all_ifodata_same_rate_length:
wfs = self.waveform_generator.generate(**params)
else:
wfs = {}
for det in self.data:
wfs.update(self.waveform_generator[det].generate(**params))
except NoWaveformError:
return self._nowaveform_loglr()
except FailedWaveformError as e:
if self.ignore_failed_waveforms:
return self._nowaveform_loglr()
else:
raise e
lr = sh_total = hh_total = 0.
for det, (hp, hc) in wfs.items():
if det not in self.dets:
self.dets[det] = Detector(det)
fp, fc = self.dets[det].antenna_pattern(
params['ra'],
params['dec'],
params['polarization'],
params['tc'])
# the kmax of the waveforms may be different than internal kmax
kmax = min(max(len(hp), len(hc)), self._kmax[det])
slc = slice(self._kmin[det], kmax)
# whiten both polarizations
hp[self._kmin[det]:kmax] *= self._weight[det][slc]
hc[self._kmin[det]:kmax] *= self._weight[det][slc]
# h = fp * hp + hc * hc
# <h, d> = fp * <hp,d> + fc * <hc,d>
# the inner products
cplx_hpd = hp[slc].inner(self._whitened_data[det][slc]) # <hp, d>
cplx_hcd = hc[slc].inner(self._whitened_data[det][slc]) # <hc, d>
cplx_hd = fp * cplx_hpd + fc * cplx_hcd
# <h, h> = <fp * hp + fc * hc, fp * hp + fc * hc>
# = Real(fpfp * <hp,hp> + fcfc * <hc,hc> + \
# fphc * (<hp, hc> + <hc, hp>))
hphp = hp[slc].inner(hp[slc]).real # < hp, hp>
hchc = hc[slc].inner(hc[slc]).real # <hc, hc>
# Below could be combined, but too tired to figure out
# if there should be a sign applied if so
hphc = hp[slc].inner(hc[slc]).real # <hp, hc>
hchp = hc[slc].inner(hp[slc]).real # <hc, hp>
hh = fp * fp * hphp + fc * fc * hchc + fp * fc * (hphc + hchp)
# store
setattr(self._current_stats, '{}_optimal_snrsq'.format(det), hh)
sh_total += cplx_hd
hh_total += hh
lr, idx, maxl = self.marginalize_loglr(sh_total, hh_total,
return_peak=True)
# store the maxl polarization
setattr(self._current_stats,
'maxl_polarization',
params['polarization'])
setattr(self._current_stats, 'maxl_loglr', maxl)
# just store the maxl optimal snrsq
for det in wfs:
p = '{}_optimal_snrsq'.format(det)
setattr(self._current_stats, p,
getattr(self._current_stats, p)[idx])
return lr
[docs]
class MarginalizedHMPolPhase(BaseGaussianNoise):
r"""Numerically marginalizes waveforms with higher modes over polarization
`and` phase.
This class implements the Gaussian likelihood with an explicit numerical
marginalization over polarization angle and orbital phase. This is
accomplished using a fixed set of integration points distributed uniformly
between 0 and 2:math:`\pi` for both the polarization and phase. By default,
100 integration points are used for each parameter, giving :math:`10^4`
evaluation points in total. This can be modified using the
``polarization_samples`` and ``coa_phase_samples`` arguments.
This only works with waveforms that return separate spherical harmonic
modes for each waveform. For a list of currently supported approximants,
see :py:func:`pycbc.waveform.waveform_modes.fd_waveform_mode_approximants`
and :py:func:`pycbc.waveform.waveform_modes.td_waveform_mode_approximants`.
Parameters
----------
variable_params : (tuple of) string(s)
A tuple of parameter names that will be varied.
data : dict
A dictionary of data, in which the keys are the detector names and the
values are the data (assumed to be unwhitened). All data must have the
same frequency resolution.
low_frequency_cutoff : dict
A dictionary of starting frequencies, in which the keys are the
detector names and the values are the starting frequencies for the
respective detectors to be used for computing inner products.
psds : dict, optional
A dictionary of FrequencySeries keyed by the detector names. The
dictionary must have a psd for each detector specified in the data
dictionary. If provided, the inner products in each detector will be
weighted by 1/psd of that detector.
high_frequency_cutoff : dict, optional
A dictionary of ending frequencies, in which the keys are the
detector names and the values are the ending frequencies for the
respective detectors to be used for computing inner products. If not
provided, the minimum of the largest frequency stored in the data
and a given waveform will be used.
normalize : bool, optional
If True, the normalization factor :math:`alpha` will be included in the
log likelihood. See :py:class:`GaussianNoise` for details. Default is
to not include it.
polarization_samples : int, optional
How many points to use in polarization. Default is 100.
coa_phase_samples : int, optional
How many points to use in phase. Defaults is 100.
\**kwargs :
All other keyword arguments are passed to
:py:class:`BaseGaussianNoise
<pycbc.inference.models.gaussian_noise.BaseGaussianNoise>`.
"""
name = 'marginalized_hmpolphase'
def __init__(self, variable_params, data, low_frequency_cutoff, psds=None,
high_frequency_cutoff=None, normalize=False,
polarization_samples=100,
coa_phase_samples=100,
static_params=None, **kwargs):
# set up the boiler-plate attributes
super(MarginalizedHMPolPhase, self).__init__(
variable_params, data, low_frequency_cutoff, psds=psds,
high_frequency_cutoff=high_frequency_cutoff, normalize=normalize,
static_params=static_params, **kwargs)
# create the waveform generator
self.waveform_generator = create_waveform_generator(
self.variable_params, self.data,
waveform_transforms=self.waveform_transforms,
recalibration=self.recalibration,
generator_class=generator.FDomainDetFrameModesGenerator,
gates=self.gates, **self.static_params)
pol = numpy.linspace(0, 2*numpy.pi, polarization_samples)
phase = numpy.linspace(0, 2*numpy.pi, coa_phase_samples)
# remap to every combination of the parameters
# this gets every combination by mappin them to an NxM grid
# one needs to be transposed so that they run allong opposite
# dimensions
n = coa_phase_samples * polarization_samples
self.nsamples = n
self.pol = numpy.resize(pol, n)
phase = numpy.resize(phase, n)
phase = phase.reshape(coa_phase_samples, polarization_samples)
self.phase = phase.T.flatten()
self._phase_fac = {}
self.dets = {}
[docs]
def phase_fac(self, m):
r"""The phase :math:`\exp[i m \phi]`."""
try:
return self._phase_fac[m]
except KeyError:
# hasn't been computed yet, calculate it
self._phase_fac[m] = numpy.exp(1.0j * m * self.phase)
return self._phase_fac[m]
@property
def _extra_stats(self):
"""Adds ``maxl_polarization`` and the ``maxl_phase``
"""
return ['maxl_polarization', 'maxl_phase', ]
def _nowaveform_loglr(self):
"""Convenience function to set loglr values if no waveform generated.
"""
# maxl phase doesn't exist, so set it to nan
setattr(self._current_stats, 'maxl_polarization', numpy.nan)
setattr(self._current_stats, 'maxl_phase', numpy.nan)
return -numpy.inf
def _loglr(self, return_unmarginalized=False):
r"""Computes the log likelihood ratio,
.. math::
\log \mathcal{L}(\Theta) = \sum_i
\left<h_i(\Theta)|d_i\right> -
\frac{1}{2}\left<h_i(\Theta)|h_i(\Theta)\right>,
at the current parameter values :math:`\Theta`.
Returns
-------
float
The value of the log likelihood ratio.
"""
params = self.current_params
try:
wfs = self.waveform_generator.generate(**params)
except NoWaveformError:
return self._nowaveform_loglr()
except FailedWaveformError as e:
if self.ignore_failed_waveforms:
return self._nowaveform_loglr()
else:
raise e
# ---------------------------------------------------------------------
# Some optimizations not yet taken:
# * higher m calculations could have a lot of redundancy
# * fp/fc need not be calculated except where polarization is different
# * may be possible to simplify this by making smarter use of real/imag
# ---------------------------------------------------------------------
lr = 0.
hds = {}
hhs = {}
for det, modes in wfs.items():
if det not in self.dets:
self.dets[det] = Detector(det)
fp, fc = self.dets[det].antenna_pattern(params['ra'],
params['dec'],
self.pol,
params['tc'])
# loop over modes and prepare the waveform modes
# we will sum up zetalm = glm <ulm, d> + i glm <vlm, d>
# over all common m so that we can apply the phase once
zetas = {}
rlms = {}
slms = {}
for mode in modes:
l, m = mode
ulm, vlm = modes[mode]
# whiten the waveforms
# the kmax of the waveforms may be different than internal kmax
kmax = min(max(len(ulm), len(vlm)), self._kmax[det])
slc = slice(self._kmin[det], kmax)
ulm[self._kmin[det]:kmax] *= self._weight[det][slc]
vlm[self._kmin[det]:kmax] *= self._weight[det][slc]
# the inner products
# <ulm, d>
ulmd = ulm[slc].inner(self._whitened_data[det][slc]).real
# <vlm, d>
vlmd = vlm[slc].inner(self._whitened_data[det][slc]).real
# add inclination, and pack into a complex number
import lal
glm = lal.SpinWeightedSphericalHarmonic(
params['inclination'], 0, -2, l, m).real
if m not in zetas:
zetas[m] = 0j
zetas[m] += glm * (ulmd + 1j*vlmd)
# Get condense set of the parts of the waveform that only diff
# by m, this is used next to help calculate <h, h>
r = glm * ulm
s = glm * vlm
if m not in rlms:
rlms[m] = r
slms[m] = s
else:
rlms[m] += r
slms[m] += s
# now compute all possible <hlm, hlm>
rr_m = {}
ss_m = {}
rs_m = {}
sr_m = {}
combos = itertools.combinations_with_replacement(rlms.keys(), 2)
for m, mprime in combos:
r = rlms[m]
s = slms[m]
rprime = rlms[mprime]
sprime = slms[mprime]
rr_m[mprime, m] = r[slc].inner(rprime[slc]).real
ss_m[mprime, m] = s[slc].inner(sprime[slc]).real
rs_m[mprime, m] = s[slc].inner(rprime[slc]).real
sr_m[mprime, m] = r[slc].inner(sprime[slc]).real
# store the conjugate for easy retrieval later
rr_m[m, mprime] = rr_m[mprime, m]
ss_m[m, mprime] = ss_m[mprime, m]
rs_m[m, mprime] = sr_m[mprime, m]
sr_m[m, mprime] = rs_m[mprime, m]
# now apply the phase to all the common ms
hpd = 0.
hcd = 0.
hphp = 0.
hchc = 0.
hphc = 0.
for m, zeta in zetas.items():
phase_coeff = self.phase_fac(m)
# <h+, d> = (exp[i m phi] * zeta).real()
# <hx, d> = -(exp[i m phi] * zeta).imag()
z = phase_coeff * zeta
hpd += z.real
hcd -= z.imag
# now calculate the contribution to <h, h>
cosm = phase_coeff.real
sinm = phase_coeff.imag
for mprime in zetas:
pcprime = self.phase_fac(mprime)
cosmprime = pcprime.real
sinmprime = pcprime.imag
# needed components
rr = rr_m[m, mprime]
ss = ss_m[m, mprime]
rs = rs_m[m, mprime]
sr = sr_m[m, mprime]
# <hp, hp>
hphp += rr * cosm * cosmprime \
+ ss * sinm * sinmprime \
- rs * cosm * sinmprime \
- sr * sinm * cosmprime
# <hc, hc>
hchc += rr * sinm * sinmprime \
+ ss * cosm * cosmprime \
+ rs * sinm * cosmprime \
+ sr * cosm * sinmprime
# <hp, hc>
hphc += -rr * cosm * sinmprime \
+ ss * sinm * cosmprime \
+ sr * sinm * sinmprime \
- rs * cosm * cosmprime
# Now apply the polarizations and calculate the loglr
# We have h = Fp * hp + Fc * hc
# loglr = <h, d> - <h, h>/2
# = Fp*<hp, d> + Fc*<hc, d>
# - (1/2)*(Fp*Fp*<hp, hp> + Fc*Fc*<hc, hc>
# + 2*Fp*Fc<hp, hc>)
# (in the last line we have made use of the time series being
# real, so that <a, b> = <b, a>).
hd = fp * hpd + fc * hcd
hh = fp * fp * hphp + fc * fc * hchc + 2 * fp * fc * hphc
hds[det] = hd
hhs[det] = hh
lr += hd - 0.5 * hh
if return_unmarginalized:
return self.pol, self.phase, lr, hds, hhs
lr_total = special.logsumexp(lr) - numpy.log(self.nsamples)
# store the maxl values
idx = lr.argmax()
setattr(self._current_stats, 'maxl_polarization', self.pol[idx])
setattr(self._current_stats, 'maxl_phase', self.phase[idx])
return float(lr_total)