From 234ff4cd7c4ef5acd7353ea4d1aabcd0574e83e3 Mon Sep 17 00:00:00 2001
From: Gregory Ashton <gregory.ashton@ligo.org>
Date: Mon, 2 Jul 2018 14:21:05 +1000
Subject: [PATCH] Update from using alpha to a time of roll off
---
tupak/gw/detector.py | 44 +++++++++++++++++++++++++-------------------
1 file changed, 25 insertions(+), 19 deletions(-)
diff --git a/tupak/gw/detector.py b/tupak/gw/detector.py
index 7a3d1abc2..b6fec6528 100644
--- a/tupak/gw/detector.py
+++ b/tupak/gw/detector.py
@@ -320,12 +320,18 @@ class InterferometerStrainData(object):
strain = strain.filter(bp, filtfilt=True)
self._time_domain_strain = strain.value
- def apply_tukey_window(self, alpha):
+ def get_tukey_window(self, N, roll_off):
+ alpha = 2 * roll_off / self.duration
+ window = signal.windows.tukey(N, alpha=alpha)
+ return window
+
+ def apply_tukey_window(self, roll_off):
N = len(self.time_domain_strain)
- self._time_domain_strain *= signal.windows.tukey(N, alpha=alpha)
+ window = self.get_tukey_window(N, roll_off=roll_off)
+ self._time_domain_strain *= window
def create_power_spectral_density(
- self, name, analysis_segment_duration, alpha, outdir='outdir'):
+ self, name, analysis_segment_duration, roll_off, outdir='outdir'):
""" Use the time domain strain to generate a power spectral density
This create a Tukey-windowed power spectral density and writes it to a
@@ -337,8 +343,8 @@ class InterferometerStrainData(object):
The name of the detector, used in storing the PSD
analysis_segment_duration: float
Duration of the analysis segment.
- alpha: float
- The tukey window shape parameter passed to `scipy.signal.tukey`.
+ roll_off: float
+ The roll-off (in seconds) used in the Tukey window.
outdir: str
The output directory to write the PSD file too
@@ -349,7 +355,7 @@ class InterferometerStrainData(object):
"""
NFFT = int(self.sampling_frequency * analysis_segment_duration)
- window = signal.windows.tukey(NFFT, alpha=alpha)
+ window = self.get_tukey_window(N=NFFT, roll_off=roll_off)
strain = gwpy.timeseries.TimeSeries(
self.time_domain_strain, sample_rate=self.sampling_frequency)
psd = strain.psd(fftlength=analysis_segment_duration, window=window)
@@ -674,8 +680,8 @@ class Interferometer(object):
buffer_time: float
Read in data with `start_time-buffer_time` and
`start_time+duration+buffer_time`
- alpha: float
- The tukey window shape parameter passed to `scipy.signal.tukey`.
+ roll_off: float
+ The roll-off (in seconds) used in the Tukey window.
filter_freq: float
Low pass filter frequency. If None, defaults to the maximum
frequency given to InterferometerStrainData.
@@ -1234,8 +1240,8 @@ class PowerSpectralDensity(object):
Offset of data from beginning of analysed segment.
channel_name: str, optional
Name of channel to use to generate PSD.
- alpha: float, optional
- Parameter for Tukey window.
+ roll_off: float
+ The roll-off (in seconds) used in the Tukey window.
fft_length: float, optional
Number of seconds in a single fft.
@@ -1442,7 +1448,7 @@ def load_interferometer(filename):
def get_interferometer_with_open_data(
- name, trigger_time, time_duration=4, start_time=None, alpha=0.25, psd_offset=-1024,
+ name, trigger_time, time_duration=4, start_time=None, roll_off=0.4, psd_offset=-1024,
psd_duration=100, cache=True, outdir='outdir', label=None, plot=True, filter_freq=1024,
raw_data_file=None, **kwargs):
"""
@@ -1461,8 +1467,8 @@ def get_interferometer_with_open_data(
start_time: float, optional
Beginning of the segment, if None, the trigger is placed 2s before the end
of the segment.
- alpha: float, optional
- The tukey window shape parameter passed to `scipy.signal.tukey`.
+ roll_off: float
+ The roll-off (in seconds) used in the Tukey window.
psd_offset, psd_duration: float
The power spectral density (psd) is estimated using data from
`center_time+psd_offset` to `center_time+psd_offset + psd_duration`.
@@ -1514,10 +1520,10 @@ def get_interferometer_with_open_data(
# Create and save PSDs
psd_file = strain_psd.create_power_spectral_density(
- name=name, alpha=alpha, outdir=outdir,
+ name=name, roll_off=roll_off, outdir=outdir,
analysis_segment_duration=strain.duration)
- strain.apply_tukey_window(alpha=alpha)
+ strain.apply_tukey_window(roll_off=roll_off)
interferometer = get_empty_interferometer(name)
interferometer.power_spectral_density = PowerSpectralDensity(
@@ -1610,7 +1616,7 @@ def get_interferometer_with_fake_noise_and_injection(
def get_event_data(
- event, interferometer_names=None, time_duration=4, alpha=0.25,
+ event, interferometer_names=None, time_duration=4, roll_off=0.4,
psd_offset=-1024, psd_duration=100, cache=True, outdir='outdir',
label=None, plot=True, filter_freq=1024, raw_data_file=None, **kwargs):
"""
@@ -1626,8 +1632,8 @@ def get_event_data(
If None will look for data in 'H1', 'V1', 'L1'
time_duration: float
Time duration to search for.
- alpha: float
- The tukey window shape parameter passed to `scipy.signal.tukey`.
+ roll_off: float
+ The roll-off (in seconds) used in the Tukey window.
psd_offset, psd_duration: float
The power spectral density (psd) is estimated using data from
`center_time+psd_offset` to `center_time+psd_offset + psd_duration`.
@@ -1664,7 +1670,7 @@ def get_event_data(
for name in interferometer_names:
try:
interferometers.append(get_interferometer_with_open_data(
- name, trigger_time=event_time, time_duration=time_duration, alpha=alpha,
+ name, trigger_time=event_time, time_duration=time_duration, roll_off=roll_off,
psd_offset=psd_offset, psd_duration=psd_duration, cache=cache,
outdir=outdir, label=label, plot=plot, filter_freq=filter_freq,
raw_data_file=raw_data_file, **kwargs))
--
GitLab