gate.py
# Copyright (C) 2016 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.
""" Functions for applying gates to data.
"""
from scipy import linalg
from . import strain
def _gates_from_cli(opts, gate_opt):
"""Parses the given `gate_opt` into something understandable by
`strain.gate_data`.
"""
gates = {}
if getattr(opts, gate_opt) is None:
return gates
for gate in getattr(opts, gate_opt):
try:
ifo, central_time, half_dur, taper_dur = gate.split(':')
central_time = float(central_time)
half_dur = float(half_dur)
taper_dur = float(taper_dur)
except ValueError:
raise ValueError("--gate {} not formatted correctly; ".format(
gate) + "see help")
try:
gates[ifo].append((central_time, half_dur, taper_dur))
except KeyError:
gates[ifo] = [(central_time, half_dur, taper_dur)]
return gates
def gates_from_cli(opts):
"""Parses the --gate option into something understandable by
`strain.gate_data`.
"""
return _gates_from_cli(opts, 'gate')
def psd_gates_from_cli(opts):
"""Parses the --psd-gate option into something understandable by
`strain.gate_data`.
"""
return _gates_from_cli(opts, 'psd_gate')
def apply_gates_to_td(strain_dict, gates):
"""Applies the given dictionary of gates to the given dictionary of
strain.
Parameters
----------
strain_dict : dict
Dictionary of time-domain strain, keyed by the ifos.
gates : dict
Dictionary of gates. Keys should be the ifo to apply the data to,
values are a tuple giving the central time of the gate, the half
duration, and the taper duration.
Returns
-------
dict
Dictionary of time-domain strain with the gates applied.
"""
# copy data to new dictionary
outdict = dict(strain_dict.items())
for ifo in gates:
outdict[ifo] = strain.gate_data(outdict[ifo], gates[ifo])
return outdict
def apply_gates_to_fd(stilde_dict, gates):
"""Applies the given dictionary of gates to the given dictionary of
strain in the frequency domain.
Gates are applied by IFFT-ing the strain data to the time domain, applying
the gate, then FFT-ing back to the frequency domain.
Parameters
----------
stilde_dict : dict
Dictionary of frequency-domain strain, keyed by the ifos.
gates : dict
Dictionary of gates. Keys should be the ifo to apply the data to,
values are a tuple giving the central time of the gate, the half
duration, and the taper duration.
Returns
-------
dict
Dictionary of frequency-domain strain with the gates applied.
"""
# copy data to new dictionary
outdict = dict(stilde_dict.items())
# create a time-domin strain dictionary to apply the gates to
strain_dict = dict([[ifo, outdict[ifo].to_timeseries()] for ifo in gates])
# apply gates and fft back to the frequency domain
for ifo,d in apply_gates_to_td(strain_dict, gates).items():
outdict[ifo] = d.to_frequencyseries()
return outdict
def add_gate_option_group(parser):
"""Adds the options needed to apply gates to data.
Parameters
----------
parser : object
ArgumentParser instance.
"""
gate_group = parser.add_argument_group("Options for gating data")
gate_group.add_argument("--gate", nargs="+", type=str,
metavar="IFO:CENTRALTIME:HALFDUR:TAPERDUR",
help="Apply one or more gates to the data before "
"filtering.")
gate_group.add_argument("--gate-overwhitened", action="store_true",
help="Overwhiten data first, then apply the "
"gates specified in --gate. Overwhitening "
"allows for sharper tapers to be used, "
"since lines are not blurred.")
gate_group.add_argument("--psd-gate", nargs="+", type=str,
metavar="IFO:CENTRALTIME:HALFDUR:TAPERDUR",
help="Apply one or more gates to the data used "
"for computing the PSD. Gates are applied "
"prior to FFT-ing the data for PSD "
"estimation.")
return gate_group
def gate_and_paint(data, lindex, rindex, invpsd, copy=True):
"""Gates and in-paints data.
Parameters
----------
data : TimeSeries
The data to gate.
lindex : int
The start index of the gate.
rindex : int
The end index of the gate.
invpsd : FrequencySeries
The inverse of the PSD.
copy : bool, optional
Copy the data before applying the gate. Otherwise, the gate will
be applied in-place. Default is True.
Returns
-------
TimeSeries :
The gated and in-painted time series.
"""
# Uses the hole-filling method of
# https://arxiv.org/pdf/1908.05644.pdf
# Copy the data and zero inside the hole
if copy:
data = data.copy()
data[lindex:rindex] = 0
# get the over-whitened gated data
tdfilter = invpsd.astype('complex').to_timeseries() * invpsd.delta_t
owhgated_data = (data.to_frequencyseries() * invpsd).to_timeseries()
# remove the projection into the null space
proj = linalg.solve_toeplitz(tdfilter[:(rindex - lindex)],
owhgated_data[lindex:rindex])
data[lindex:rindex] -= proj
return data
