def normal(start, end, seed=0):
""" Generate data with a white Gaussian (normal) distribution
Parameters
----------
start_time : int
Start time in GPS seconds to generate noise
end_time : int
End time in GPS seconds to generate nosie
seed : {None, int}
The seed to generate the noise.
Returns
--------
noise : TimeSeries
A TimeSeries containing gaussian noise
"""
# This is reproduceable because we used fixed seeds from known values
s = int(start / BLOCK_SIZE)
e = int(end / BLOCK_SIZE)
# The data evenly divides so the last block would be superfluous
if end % BLOCK_SIZE == 0:
e -= 1
sv = RandomState(seed).randint(-2**50, 2**50)
data = numpy.concatenate([block(i + sv) for i in numpy.arange(s, e + 1, 1)])
ts = TimeSeries(data, delta_t=1.0 / SAMPLE_RATE, epoch=start)
return ts.time_slice(start, end)
def line_model(freq, data, tref, amp=1, phi=0):
""" Simple time-domain model for a frequency line.
Parameters
----------
freq: float
Frequency of the line.
data: pycbc.types.TimeSeries
Reference data, to get delta_t, start_time, duration and sample_times.
tref: float
Reference time for the line model.
amp: {1., float}, optional
Amplitude of the frequency line.
phi: {0. float}, optional
Phase of the frequency line (radians).
Returns
-------
freq_line: pycbc.types.TimeSeries
A timeseries of the line model with frequency 'freq'. The returned
data are complex to allow measuring the amplitude and phase of the
corresponding frequency line in the strain data. For extraction, use
only the real part of the data.
"""
freq_line = TimeSeries(zeros(len(data)), delta_t=data.delta_t,
epoch=data.start_time)
times = data.sample_times - float(tref)
alpha = 2 * numpy.pi * freq * times + phi
freq_line.data = amp * numpy.exp(1.j * alpha)
return freq_line
def noise_from_psd(length, delta_t, psd, seed=None):
""" Create noise with a given psd.
Return noise with a given psd. Note that if unique noise is desired
a unique seed should be provided.
Parameters
----------
length : int
The length of noise to generate in samples.
delta_t : float
The time step of the noise.
psd : FrequencySeries
The noise weighting to color the noise.
seed : {0, int}
The seed to generate the noise.
Returns
--------
noise : TimeSeries
A TimeSeries containing gaussian noise colored by the given psd.
"""
noise_ts = TimeSeries(zeros(length), delta_t=delta_t)
if seed is None:
seed = numpy.random.randint(2**32)
randomness = lal.gsl_rng("ranlux", seed)
N = int (1.0 / delta_t / psd.delta_f)
n = N/2+1
stride = N/2
if n > len(psd):
raise ValueError("PSD not compatible with requested delta_t")
psd = (psd[0:n]).lal()
psd.data.data[n-1] = 0
segment = TimeSeries(zeros(N), delta_t=delta_t).lal()
length_generated = 0
SimNoise(segment, 0, psd, randomness)
while (length_generated < length):
if (length_generated + stride) < length:
noise_ts.data[length_generated:length_generated+stride] = segment.data.data[0:stride]
else:
noise_ts.data[length_generated:length] = segment.data.data[0:length-length_generated]
length_generated += stride
SimNoise(segment, stride, psd, randomness)
return noise_ts
def test_injection_presence(self):
"""Verify presence of signals at expected times"""
injections = InjectionSet(self.inj_file.name)
for det in self.detectors:
for inj in self.injections:
ts = TimeSeries(numpy.zeros(10 * self.sample_rate),
delta_t=1/self.sample_rate,
epoch=lal.LIGOTimeGPS(inj.end_time - 5),
dtype=numpy.float64)
injections.apply(ts, det.name)
max_amp, max_loc = ts.abs_max_loc()
# FIXME could test amplitude and time more precisely
self.assertTrue(max_amp > 0 and max_amp < 1e-10)
time_error = ts.sample_times.numpy()[max_loc] - inj.end_time
self.assertTrue(abs(time_error) < 1.5 * self.earth_time)
def test_injection_absence(self):
"""Verify absence of signals outside known injection times"""
clear_times = [
self.injections[0].end_time - 86400,
self.injections[-1].end_time + 86400
]
injections = InjectionSet(self.inj_file.name)
for det in self.detectors:
for epoch in clear_times:
ts = TimeSeries(numpy.zeros(10 * self.sample_rate),
delta_t=1/self.sample_rate,
epoch=lal.LIGOTimeGPS(epoch),
dtype=numpy.float64)
injections.apply(ts, det.name)
max_amp, max_loc = ts.abs_max_loc()
self.assertEqual(max_amp, 0)
def __init__(self, frame_src,
channel_name,
start_time,
max_buffer=2048,
force_update_cache=True,
increment_update_cache=None):
""" Create a rolling buffer of frame data
Parameters
---------
frame_src: str of list of strings
Strings that indicate where to read from files from. This can be a
list of frame files, a glob, etc.
channel_name: str
Name of the channel to read from the frame files
start_time:
Time to start reading from.
max_buffer: {int, 2048}, Optional
Length of the buffer in seconds
"""
self.frame_src = frame_src
self.channel_name = channel_name
self.read_pos = start_time
self.force_update_cache = force_update_cache
self.increment_update_cache = increment_update_cache
self.update_cache()
self.channel_type, self.raw_sample_rate = self._retrieve_metadata(self.stream, self.channel_name)
raw_size = self.raw_sample_rate * max_buffer
self.raw_buffer = TimeSeries(zeros(raw_size, dtype=numpy.float64),
copy=False,
epoch=start_time - max_buffer,
delta_t=1.0/self.raw_sample_rate)
def interpolate_complex_frequency(series, delta_f, zeros_offset=0, side='right'):
"""Interpolate complex frequency series to desired delta_f.
Return a new complex frequency series that has been interpolated to the
desired delta_f.
Parameters
----------
series : FrequencySeries
Frequency series to be interpolated.
delta_f : float
The desired delta_f of the output
zeros_offset : optional, {0, int}
Number of sample to delay the start of the zero padding
side : optional, {'right', str}
The side of the vector to zero pad
Returns
-------
interpolated series : FrequencySeries
A new FrequencySeries that has been interpolated.
"""
new_n = int( (len(series)-1) * series.delta_f / delta_f + 1)
samples = numpy.arange(0, new_n) * delta_f
old_N = int( (len(series)-1) * 2 )
new_N = int( (new_n - 1) * 2 )
time_series = TimeSeries(zeros(old_N), delta_t =1.0/(series.delta_f*old_N),
dtype=real_same_precision_as(series))
ifft(series, time_series)
time_series.roll(-zeros_offset)
time_series.resize(new_N)
if side == 'left':
time_series.roll(zeros_offset + new_N - old_N)
elif side == 'right':
time_series.roll(zeros_offset)
out_series = FrequencySeries(zeros(new_n), epoch=series.epoch,
delta_f=delta_f, dtype=series.dtype)
fft(time_series, out_series)
return out_series
def phase_from_polarizations(h_plus, h_cross, remove_start_phase=True):
"""Return gravitational wave phase
Return the gravitation-wave phase from the h_plus and h_cross
polarizations of the waveform. The returned phase is always
positive and increasing with an initial phase of 0.
Parameters
----------
h_plus : TimeSeries
An PyCBC TmeSeries vector that contains the plus polarization of the
gravitational waveform.
h_cross : TimeSeries
A PyCBC TmeSeries vector that contains the cross polarization of the
gravitational waveform.
Returns
-------
GWPhase : TimeSeries
A TimeSeries containing the gravitational wave phase.
Examples
--------s
>>> from pycbc.waveform import get_td_waveform, phase_from_polarizations
>>> hp, hc = get_td_waveform(approximant="TaylorT4", mass1=10, mass2=10,
f_lower=30, delta_t=1.0/4096)
>>> phase = phase_from_polarizations(hp, hc)
"""
p = numpy.unwrap(numpy.arctan2(h_cross.data, h_plus.data)).astype(
real_same_precision_as(h_plus))
if remove_start_phase:
p += -p[0]
return TimeSeries(p,
delta_t=h_plus.delta_t,
epoch=h_plus.start_time,
copy=False)
def test_chirp(self):
### use a chirp as a signal
sigt = TimeSeries(self.sig1, self.del_t)
sig_tilde = make_frequency_series(sigt)
del_f = sig_tilde.get_delta_f()
psd = FrequencySeries(self.Psd, del_f)
flow = self.low_frequency_cutoff
with _context:
hautocor, hacorfr, hnrm = matched_filter_core(self.htilde, self.htilde, psd=psd, \
low_frequency_cutoff=flow, high_frequency_cutoff=self.fmax)
hautocor = hautocor * float(np.real(1./hautocor[0]))
snr, cor, nrm = matched_filter_core(self.htilde, sig_tilde, psd=psd, \
low_frequency_cutoff=flow, high_frequency_cutoff=self.fmax)
hacor = Array(hautocor, copy=True)
indx = np.array([352250, 352256, 352260])
snr = snr*nrm
with _context:
dof, achisq, indices= \
autochisq_from_precomputed(snr, snr, hacor, indx, stride=3,
num_points=20)
obt_snr = abs(snr[indices[1]])
obt_ach = achisq[1]
self.assertTrue(obt_snr > 10.0 and obt_snr < 12.0)
self.assertTrue(obt_ach < 3.e-3)
self.assertTrue(achisq[0] > 20.0)
self.assertTrue(achisq[2] > 20.0)
def frequency_from_polarizations(h_plus, h_cross):
"""Return gravitational wave frequency
Return the gravitation-wave frequency as a function of time
from the h_plus and h_cross polarizations of the waveform.
It is 1 bin shorter than the input vectors and the sample times
are advanced half a bin.
Parameters
----------
h_plus : TimeSeries
A PyCBC TimeSeries vector that contains the plus polarization of the
gravitational waveform.
h_cross : TimeSeries
A PyCBC TimeSeries vector that contains the cross polarization of the
gravitational waveform.
Returns
-------
GWFrequency : TimeSeries
A TimeSeries containing the gravitational wave frequency as a function
of time.
Examples
--------
>>> from pycbc.waveform import get_td_waveform, phase_from_polarizations
>>> hp, hc = get_td_waveform(approximant="TaylorT4", mass1=10, mass2=10,
f_lower=30, delta_t=1.0/4096)
>>> freq = frequency_from_polarizations(hp, hc)
"""
phase = phase_from_polarizations(h_plus, h_cross)
freq = numpy.diff(phase) / (2 * lal.PI * phase.delta_t)
start_time = phase.start_time + phase.delta_t / 2
return TimeSeries(freq.astype(real_same_precision_as(h_plus)),
delta_t=phase.delta_t,
epoch=start_time)
def taper_timeseries(tsdata, tapermethod=None, return_lal=False):
"""
Taper either or both ends of a time series using wrapped
LALSimulation functions
Parameters
----------
tsdata : TimeSeries
Series to be tapered, dtype must be either float32 or float64
tapermethod : string
Should be one of ('TAPER_NONE', 'TAPER_START', 'TAPER_END',
'TAPER_STARTEND', 'start', 'end', 'startend') - NB 'TAPER_NONE' will
not change the series!
return_lal : Boolean
If True, return a wrapped LAL time series object, else return a
PyCBC time series.
"""
if tapermethod is None:
raise ValueError("Must specify a tapering method (function was called"
"with tapermethod=None)")
if tapermethod not in taper_map.keys():
raise ValueError("Unknown tapering method %s, valid methods are %s" % \
(tapermethod, ", ".join(taper_map.keys())))
if tsdata.dtype not in (float32, float64):
raise TypeError("Strain dtype must be float32 or float64, not " +
str(tsdata.dtype))
taper_func = taper_func_map[tsdata.dtype]
# make a LAL TimeSeries to pass to the LALSim function
ts_lal = tsdata.astype(tsdata.dtype).lal()
if taper_map[tapermethod] is not None:
taper_func(ts_lal.data, taper_map[tapermethod])
if return_lal:
return ts_lal
else:
return TimeSeries(ts_lal.data.data[:],
delta_t=ts_lal.deltaT,
epoch=ts_lal.epoch)
def highpass_fir(timeseries, frequency, order, beta=5.0):
""" Highpass filter the time series using an FIR filtered generated from
the ideal response passed through a kaiser window (beta = 5.0)
Parameters
----------
Time Series: TimeSeries
The time series to be high-passed.
frequency: float
The frequency below which is suppressed.
order: int
Number of corrupted samples on each side of the time series
beta: float
Beta parameter of the kaiser window that sets the side lobe attenuation.
"""
k = frequency / float((int(1.0 / timeseries.delta_t) / 2))
coeff = scipy.signal.firwin(order * 2 + 1,
k,
window=('kaiser', beta),
pass_zero=False)
data = fir_zero_filter(coeff, timeseries)
return TimeSeries(data,
epoch=timeseries.start_time,
delta_t=timeseries.delta_t)
class DataBuffer(object):
"""A linear buffer that acts as a FILO for reading in frame data
"""
def __init__(self, frame_src,
channel_name,
start_time,
max_buffer=2048,
force_update_cache=True,
increment_update_cache=None,
dtype=numpy.float64):
""" Create a rolling buffer of frame data
Parameters
---------
frame_src: str of list of strings
Strings that indicate where to read from files from. This can be a
list of frame files, a glob, etc.
channel_name: str
Name of the channel to read from the frame files
start_time:
Time to start reading from.
max_buffer: {int, 2048}, Optional
Length of the buffer in seconds
dtype: {dtype, numpy.float32}, Optional
Data type to use for the interal buffer
"""
self.frame_src = frame_src
self.channel_name = channel_name
self.read_pos = start_time
self.force_update_cache = force_update_cache
self.increment_update_cache = increment_update_cache
self.detector = channel_name.split(':')[0]
self.update_cache()
self.channel_type, self.raw_sample_rate = self._retrieve_metadata(self.stream, self.channel_name)
raw_size = self.raw_sample_rate * max_buffer
self.raw_buffer = TimeSeries(zeros(raw_size, dtype=dtype),
copy=False,
epoch=start_time - max_buffer,
delta_t=1.0/self.raw_sample_rate)
def update_cache(self):
"""Reset the lal cache. This can be used to update the cache if the
result may change due to more files being added to the filesystem,
for example.
"""
cache = locations_to_cache(self.frame_src)
stream = lalframe.FrStreamCacheOpen(cache)
self.stream = stream
@staticmethod
def _retrieve_metadata(stream, channel_name):
"""Retrieve basic metadata by reading the first file in the cache
Parameters
----------
stream: lal stream object
Stream containing a channel we want to learn about
channel_name: str
The name of the channel we want to know the dtype and sample rate of
Returns
-------
channel_type: lal type enum
Enum value which indicates the dtype of the channel
sample_rate: int
The sample rate of the data within this channel
"""
lalframe.FrStreamGetVectorLength(channel_name, stream)
channel_type = lalframe.FrStreamGetTimeSeriesType(channel_name, stream)
create_series_func = _fr_type_map[channel_type][2]
get_series_metadata_func = _fr_type_map[channel_type][3]
series = create_series_func(channel_name, stream.epoch, 0, 0,
lal.ADCCountUnit, 0)
get_series_metadata_func(series, stream)
return channel_type, int(1.0/series.deltaT)
def _read_frame(self, blocksize):
"""Try to read the block of data blocksize seconds long
Parameters
----------
blocksize: int
The number of seconds to attempt to read from the channel
Returns
-------
data: TimeSeries
TimeSeries containg 'blocksize' seconds of frame data
Raises
------
RuntimeError:
If data cannot be read for any reason
"""
try:
read_func = _fr_type_map[self.channel_type][0]
dtype = _fr_type_map[self.channel_type][1]
data = read_func(self.stream, self.channel_name,
self.read_pos, int(blocksize), 0)
return TimeSeries(data.data.data, delta_t=data.deltaT,
epoch=self.read_pos,
dtype=dtype)
except Exception:
raise RuntimeError('Cannot read {0} frame data'.format(self.channel_name))
def null_advance(self, blocksize):
"""Advance and insert zeros
Parameters
----------
blocksize: int
The number of seconds to attempt to read from the channel
"""
self.raw_buffer.roll(-int(blocksize * self.raw_sample_rate))
self.read_pos += blocksize
self.raw_buffer.start_time += blocksize
def advance(self, blocksize):
"""Add blocksize seconds more to the buffer, push blocksize seconds
from the beginning.
Parameters
----------
blocksize: int
The number of seconds to attempt to read from the channel
"""
ts = self._read_frame(blocksize)
self.raw_buffer.roll(-len(ts))
self.raw_buffer[-len(ts):] = ts[:]
self.read_pos += blocksize
self.raw_buffer.start_time += blocksize
return ts
def update_cache_by_increment(self, blocksize):
"""Update the internal cache by starting from the first frame
and incrementing.
Guess the next frame file name by incrementing from the first found
one. This allows a pattern to be used for the GPS folder of the file,
which is indicated by `GPSX` where x is the number of digits to use.
Parameters
----------
blocksize: int
Number of seconds to increment the next frame file.
"""
start = float(self.raw_buffer.end_time)
end = float(start + blocksize)
if not hasattr(self, 'dur'):
fname = glob.glob(self.frame_src[0])[0]
fname = os.path.splitext(os.path.basename(fname))[0].split('-')
self.beg = '-'.join([fname[0], fname[1]])
self.ref = int(fname[2])
self.dur = int(fname[3])
fstart = int(self.ref + numpy.floor((start - self.ref) / float(self.dur)) * self.dur)
starts = numpy.arange(fstart, end, self.dur).astype(numpy.int)
keys = []
for s in starts:
pattern = self.increment_update_cache
if 'GPS' in pattern:
n = int(pattern[int(pattern.index('GPS') + 3)])
pattern = pattern.replace('GPS%s' % n, str(s)[0:n])
name = '%s/%s-%s-%s.gwf' % (pattern, self.beg, s, self.dur)
# check that file actually exists, else abort now
if not os.path.exists(name):
logging.info("%s does not seem to exist yet" % name)
raise RuntimeError
keys.append(name)
cache = locations_to_cache(keys)
stream = lalframe.FrStreamCacheOpen(cache)
self.stream = stream
self.channel_type, self.raw_sample_rate = \
self._retrieve_metadata(self.stream, self.channel_name)
def attempt_advance(self, blocksize, timeout=10):
""" Attempt to advance the frame buffer. Retry upon failure, except
if the frame file is beyond the timeout limit.
Parameters
----------
blocksize: int
The number of seconds to attempt to read from the channel
timeout: {int, 10}, Optional
Number of seconds before giving up on reading a frame
Returns
-------
data: TimeSeries
TimeSeries containg 'blocksize' seconds of frame data
"""
if self.force_update_cache:
self.update_cache()
try:
if self.increment_update_cache:
self.update_cache_by_increment(blocksize)
return DataBuffer.advance(self, blocksize)
except RuntimeError:
if lal.GPSTimeNow() > timeout + self.raw_buffer.end_time:
# The frame is not there and it should be by now, so we give up
# and treat it as zeros
DataBuffer.null_advance(self, blocksize)
return None
else:
# I am too early to give up on this frame, so we should try again
time.sleep(1)
return self.attempt_advance(blocksize, timeout=timeout)
def get_td_lm_allmodes(template=None, taper=None, **kwargs):
"""Return time domain ringdown with all the modes specified.
Parameters
----------
template: object
An object that has attached properties. This can be used to substitute
for keyword arguments. A common example would be a row in an xml table.
taper: {None, float}, optional
Tapering at the beginning of the waveform with duration taper * tau.
This option is recommended with timescales taper=1./2 or 1. for
time-domain ringdown-only injections.
The abrupt turn on of the ringdown can cause issues on the waveform
when doing the fourier transform to the frequency domain. Setting
taper will add a rapid ringup with timescale tau/10.
Each mode and overtone will have a different taper depending on its tau,
the final taper being the superposition of all the tapers.
final_mass : float
Mass of the final black hole.
final_spin : float
Spin of the final black hole.
lmns : list
Desired lmn modes as strings (lm modes available: 22, 21, 33, 44, 55).
The n specifies the number of overtones desired for the corresponding
lm pair (maximum n=8).
Example: lmns = ['223','331'] are the modes 220, 221, 222, and 330
amp220 : float
Amplitude of the fundamental 220 mode.
amplmn : float
Fraction of the amplitude of the lmn overtone relative to the
fundamental mode, as many as the number of subdominant modes.
philmn : float
Phase of the lmn overtone, as many as the number of modes.
delta_t : {None, float}, optional
The time step used to generate the ringdown.
If None, it will be set to the inverse of the frequency at which the
amplitude is 1/1000 of the peak amplitude (the minimum of all modes).
t_final : {None, float}, optional
The ending time of the output frequency series.
If None, it will be set to the time at which the amplitude
is 1/1000 of the peak amplitude (the maximum of all modes).
Returns
-------
hplustilde: FrequencySeries
The plus phase of a ringdown with the lm modes specified and
n overtones in frequency domain.
hcrosstilde: FrequencySeries
The cross phase of a ringdown with the lm modes specified and
n overtones in frequency domain.
"""
input_params = props(template, lm_allmodes_required_args, **kwargs)
# Get required args
final_mass = input_params['final_mass']
final_spin = input_params['final_spin']
lmns = input_params['lmns']
for lmn in lmns:
if int(lmn[2]) == 0:
raise ValueError('Number of overtones (nmodes) must be greater '
'than zero.')
# following may not be in input_params
delta_t = input_params.pop('delta_t', None)
t_final = input_params.pop('t_final', None)
if delta_t is None:
delta_t = lm_deltat(final_mass, final_spin, lmns)
if t_final is None:
t_final = lm_tfinal(final_mass, final_spin, lmns)
kmax = int(t_final / delta_t) + 1
_, tau = get_lm_f0tau_allmodes(final_mass, final_spin, lmns)
# Different overtones will have different tapering window-size
# Find maximum window size to create long enough output vector
if taper is not None:
taper_window = int(taper * max(tau.values()) / delta_t)
kmax += taper_window
outplus = TimeSeries(zeros(kmax, dtype=float64), delta_t=delta_t)
outcross = TimeSeries(zeros(kmax, dtype=float64), delta_t=delta_t)
for lmn in lmns:
l, m, nmodes = int(lmn[0]), int(lmn[1]), int(lmn[2])
hplus, hcross = get_td_lm(taper=taper,
l=l,
m=m,
nmodes=nmodes,
delta_t=delta_t,
t_final=t_final,
**input_params)
if taper is None:
outplus.data += hplus.data
outcross.data += hcross.data
else:
outplus = taper_shift(hplus, outplus)
outcross = taper_shift(hcross, outcross)
return outplus, outcross
def get_td_qnm(template=None, taper=None, **kwargs):
"""Return a time domain damped sinusoid.
Parameters
----------
template: object
An object that has attached properties. This can be used to substitute
for keyword arguments. A common example would be a row in an xml table.
taper: {None, float}, optional
Tapering at the beginning of the waveform with duration taper * tau.
This option is recommended with timescales taper=1./2 or 1. for
time-domain ringdown-only injections.
The abrupt turn on of the ringdown can cause issues on the waveform
when doing the fourier transform to the frequency domain. Setting
taper will add a rapid ringup with timescale tau/10.
f_0 : float
The ringdown-frequency.
tau : float
The damping time of the sinusoid.
phi : float
The initial phase of the ringdown.
amp : float
The amplitude of the ringdown (constant for now).
delta_t : {None, float}, optional
The time step used to generate the ringdown.
If None, it will be set to the inverse of the frequency at which the
amplitude is 1/1000 of the peak amplitude.
t_final : {None, float}, optional
The ending time of the output time series.
If None, it will be set to the time at which the amplitude is
1/1000 of the peak amplitude.
Returns
-------
hplus: TimeSeries
The plus phase of the ringdown in time domain.
hcross: TimeSeries
The cross phase of the ringdown in time domain.
"""
input_params = props(template, qnm_required_args, **kwargs)
f_0 = input_params.pop('f_0')
tau = input_params.pop('tau')
amp = input_params.pop('amp')
phi = input_params.pop('phi')
# the following may not be in input_params
delta_t = input_params.pop('delta_t', None)
t_final = input_params.pop('t_final', None)
if delta_t is None:
delta_t = 1. / qnm_freq_decay(f_0, tau, 1. / 1000)
if delta_t < min_dt:
delta_t = min_dt
if t_final is None:
t_final = qnm_time_decay(tau, 1. / 1000)
kmax = int(t_final / delta_t) + 1
times = numpy.arange(kmax) * delta_t
hp = amp * numpy.exp(-times / tau) * numpy.cos(two_pi * f_0 * times + phi)
hc = amp * numpy.exp(-times / tau) * numpy.sin(two_pi * f_0 * times + phi)
# If size of tapering window is less than delta_t, do not apply taper.
if taper is None or delta_t > taper * tau:
hplus = TimeSeries(zeros(kmax), delta_t=delta_t)
hcross = TimeSeries(zeros(kmax), delta_t=delta_t)
hplus.data[:kmax] = hp
hcross.data[:kmax] = hc
return hplus, hcross
else:
taper_hp, taper_hc, taper_window, start = apply_taper(
delta_t, taper, f_0, tau, amp, phi)
hplus = TimeSeries(zeros(taper_window + kmax), delta_t=delta_t)
hcross = TimeSeries(zeros(taper_window + kmax), delta_t=delta_t)
hplus.data[:taper_window] = taper_hp
hplus.data[taper_window:] = hp
hplus._epoch = start
hcross.data[:taper_window] = taper_hc
hcross.data[taper_window:] = hc
hcross._epoch = start
return hplus, hcross
def get_td_lm(template=None, taper=None, **kwargs):
"""Return time domain lm mode with the given number of overtones.
Parameters
----------
template: object
An object that has attached properties. This can be used to substitute
for keyword arguments. A common example would be a row in an xml table.
taper: {None, float}, optional
Tapering at the beginning of the waveform with duration taper * tau.
This option is recommended with timescales taper=1./2 or 1. for
time-domain ringdown-only injections.
The abrupt turn on of the ringdown can cause issues on the waveform
when doing the fourier transform to the frequency domain. Setting
taper will add a rapid ringup with timescale tau/10.
Each overtone will have a different taper depending on its tau, the
final taper being the superposition of all the tapers.
freqs : dict
{lmn:f_lmn} Dictionary of the central frequencies for each overtone,
as many as number of modes.
taus : dict
{lmn:tau_lmn} Dictionary of the damping times for each overtone,
as many as number of modes.
l : int
l mode (lm modes available: 22, 21, 33, 44, 55).
m : int
m mode (lm modes available: 22, 21, 33, 44, 55).
nmodes: int
Number of overtones desired (maximum n=8)
amp220 : float
Amplitude of the fundamental 220 mode, needed for any lm.
amplmn : float
Fraction of the amplitude of the lmn overtone relative to the
fundamental mode, as many as the number of subdominant modes.
philmn : float
Phase of the lmn overtone, as many as the number of modes. Should also
include the information from the azimuthal angle (phi + m*Phi).
inclination : {None, float}, optional
Inclination of the system in radians for the spherical harmonics.
delta_t : {None, float}, optional
The time step used to generate the ringdown.
If None, it will be set to the inverse of the frequency at which the
amplitude is 1/1000 of the peak amplitude (the minimum of all modes).
t_final : {None, float}, optional
The ending time of the output time series.
If None, it will be set to the time at which the amplitude is
1/1000 of the peak amplitude (the maximum of all modes).
Returns
-------
hplus: TimeSeries
The plus phase of a lm mode with overtones (n) in time domain.
hcross: TimeSeries
The cross phase of a lm mode with overtones (n) in time domain.
"""
input_params = props(template, lm_required_args, **kwargs)
# Get required args
amps, phis = lm_amps_phases(**input_params)
f_0 = input_params.pop('freqs')
tau = input_params.pop('taus')
inc = input_params.pop('inclination', None)
l, m = input_params.pop('l'), input_params.pop('m')
nmodes = input_params.pop('nmodes')
if int(nmodes) == 0:
raise ValueError('Number of overtones (nmodes) must be greater '
'than zero.')
# The following may not be in input_params
delta_t = input_params.pop('delta_t', None)
t_final = input_params.pop('t_final', None)
if not delta_t:
delta_t = lm_deltat(f_0, tau, ['%d%d%d' %(l,m,nmodes)])
if not t_final:
t_final = lm_tfinal(tau, ['%d%d%d' %(l, m, nmodes)])
kmax = int(t_final / delta_t) + 1
# Different overtones will have different tapering window-size
# Find maximum window size to create long enough output vector
if taper:
taper_window = int(taper*max(tau.values())/delta_t)
kmax += taper_window
outplus = TimeSeries(zeros(kmax, dtype=float64), delta_t=delta_t)
outcross = TimeSeries(zeros(kmax, dtype=float64), delta_t=delta_t)
if taper:
start = - taper * max(tau.values())
outplus._epoch, outcross._epoch = start, start
for n in range(nmodes):
hplus, hcross = get_td_qnm(template=None, taper=taper,
f_0=f_0['%d%d%d' %(l,m,n)],
tau=tau['%d%d%d' %(l,m,n)],
phi=phis['%d%d%d' %(l,m,n)],
amp=amps['%d%d%d' %(l,m,n)],
inclination=inc, l=l, m=m,
delta_t=delta_t, t_final=t_final)
if not taper:
outplus.data += hplus.data
outcross.data += hcross.data
else:
outplus = taper_shift(hplus, outplus)
outcross = taper_shift(hcross, outcross)
return outplus, outcross
def calc_psd_variation(strain, psd_short_segment, psd_long_segment, overlap,
low_freq, high_freq):
"""Calculates time series of PSD variability
This function first splits the segment up in to 512 second chunks. It
then calculates the PSD over this 512 second period as well as in 4
second chunks throughout each 512 second period. Next the function
estimates how different the 4 second PSD is to the 512 second PSD and
produces a timeseries of this variability.
Parameters
----------
strain : TimeSeries
Input strain time series to estimate PSDs
psd_short_segment : {float, 4}
Duration of the short segments for PSD estimation in seconds.
psd_long_segment : {float, 512}
Duration of the long segments for PSD estimation in seconds.
overlap : {float, 0.5}
Duration in seconds to use for each sample of the PSD.
low_freq : {float, 20}
Minimum frequency to consider the comparison between PSDs.
high_freq : {float, 512}
Maximum frequency to consider the comparison between PSDs.
Returns
-------
psd_var : TimeSeries
Time series of the variability in the PSD estimation
"""
# Calculate strain precision
if strain.precision == 'single':
fs_dtype = numpy.float32
elif strain.precision == 'double':
fs_dtype = numpy.float64
# Convert start and end times immediately to floats
start_time = numpy.float(strain.start_time)
end_time = numpy.float(strain.end_time)
# Find the times of the long segments
times_long = numpy.arange(start_time, end_time, psd_long_segment)
# Set up the empty time series for the PSD variation estimate
psd_var = TimeSeries(zeros(
int(numpy.ceil((end_time - start_time) / psd_short_segment))),
delta_t=psd_short_segment,
copy=False,
epoch=start_time)
ind = 0
for tlong in times_long:
# Calculate PSD for long segment and separate the long segment in to
# overlapping shorter segments
if tlong + psd_long_segment <= end_time:
psd_long = strain.time_slice(tlong,
tlong + psd_long_segment).psd(overlap)
times_short = numpy.arange(tlong, tlong + psd_long_segment,
psd_short_segment)
else:
psd_long = strain.time_slice(end_time - psd_long_segment,
end_time).psd(overlap)
times_short = numpy.arange(tlong, end_time, psd_short_segment)
# Calculate the PSD of the shorter segments
psd_short = []
for tshort in times_short:
if tshort + psd_short_segment * 2 <= end_time:
pshort = strain.time_slice(tshort, tshort +
psd_short_segment * 2).psd(overlap)
else:
pshort = strain.time_slice(tshort - psd_short_segment,
end_time).psd(overlap)
psd_short.append(pshort)
# Estimate the range of the PSD to compare
kmin = int(low_freq / psd_long.delta_f)
kmax = int(high_freq / psd_long.delta_f)
# Comapre the PSD of the short segment to the long segment
# The weight factor gives the rough response of a cbc template across
# the defined frequency range given the expected PSD (i.e. long PSD)
# Then integrate the weighted ratio of the actual PSD (i.e. short PSD)
# with the expected PSD (i.e. long PSD) over the specified frequency
# range
freqs = FrequencySeries(psd_long.sample_frequencies,
delta_f=psd_long.delta_f,
epoch=psd_long.epoch,
dtype=fs_dtype)
weight = numpy.array(freqs[kmin:kmax]**(-7. / 3.) /
psd_long[kmin:kmax])
weight /= weight.sum()
diff = numpy.array([
(weight *
numpy.array(p_short[kmin:kmax] / psd_long[kmin:kmax])).sum()
for p_short in psd_short
])
# Store variation value
for i, val in enumerate(diff):
psd_var[ind + i] = val
ind = ind + len(diff)
return psd_var
def power_chisq_from_precomputed(corr,
snr,
snr_norm,
bins,
indices=None,
return_bins=False):
"""Calculate the chisq timeseries from precomputed values.
This function calculates the chisq at all times by performing an
inverse FFT of each bin.
Parameters
----------
corr: FrequencySeries
The produce of the template and data in the frequency domain.
snr: TimeSeries
The unnormalized snr time series.
snr_norm:
The snr normalization factor (true snr = snr * snr_norm) EXPLAINME - define 'true snr'?
bins: List of integers
The edges of the chisq bins.
indices: {Array, None}, optional
Index values into snr that indicate where to calculate
chisq values. If none, calculate chisq for all possible indices.
return_bins: {boolean, False}, optional
Return a list of the SNRs for each chisq bin.
Returns
-------
chisq: TimeSeries
"""
# Get workspace memory
global _q_l, _qtilde_l, _chisq_l
bin_snrs = []
if _q_l is None or len(_q_l) != len(snr):
q = zeros(len(snr), dtype=complex_same_precision_as(snr))
qtilde = zeros(len(snr), dtype=complex_same_precision_as(snr))
_q_l = q
_qtilde_l = qtilde
else:
q = _q_l
qtilde = _qtilde_l
if indices is not None:
snr = snr.take(indices)
if _chisq_l is None or len(_chisq_l) < len(snr):
chisq = zeros(len(snr), dtype=real_same_precision_as(snr))
_chisq_l = chisq
else:
chisq = _chisq_l[0:len(snr)]
chisq.clear()
num_bins = len(bins) - 1
for j in range(num_bins):
k_min = int(bins[j])
k_max = int(bins[j + 1])
qtilde[k_min:k_max] = corr[k_min:k_max]
pycbc.fft.ifft(qtilde, q)
qtilde[k_min:k_max].clear()
if return_bins:
bin_snrs.append(
TimeSeries(q * snr_norm * num_bins**0.5,
delta_t=snr.delta_t,
epoch=snr.start_time))
if indices is not None:
chisq_accum_bin(chisq, q.take(indices))
else:
chisq_accum_bin(chisq, q)
chisq = (chisq * num_bins - snr.squared_norm()) * (snr_norm**2.0)
if indices is None:
chisq = TimeSeries(chisq,
delta_t=snr.delta_t,
epoch=snr.start_time,
copy=False)
if return_bins:
return chisq, bin_snrs
else:
return chisq
from pycbc.psd import welch, interpolate
from pycbc.types import TimeSeries
try:
from urllib.request import urlretrieve
except ImportError: # python < 3
from urllib import urlretrieve
# Read data and remove low frequency content
fname = 'H-H1_LOSC_4_V2-1126259446-32.gwf'
url = "https://www.gw-openscience.org/GW150914data/" + fname
urlretrieve(url, filename=fname)
h1 = highpass_fir(read_frame(fname, 'H1:LOSC-STRAIN'), 15.0, 8)
# Calculate the noise spectrum and whiten
psd = interpolate(welch(h1), 1.0 / 32)
white_strain = (h1.to_frequencyseries() / psd ** 0.5 * psd.delta_f).to_timeseries()
# remove some of the high and low frequencies
smooth = highpass_fir(white_strain, 25, 8)
smooth = lowpass_fir(white_strain, 250, 8)
#strech out and shift the frequency upwards to aid human hearing
fdata = smooth.to_frequencyseries()
fdata.roll(int(1200 / fdata.delta_f))
smooth = TimeSeries(fdata.to_timeseries(), delta_t=1.0/1024)
#Take slice around signal
smooth = smooth[len(smooth)/2 - 1500:len(smooth)/2 + 3000]
smooth.save_to_wav('gw150914_h1_chirp.wav')
def __init__(self, filename=None, filetype='HDF5', wavetype='Auto', \
ex_order=3, group_name=None,\
modeLmin=2, modeLmax=8, skipM0=True, \
sample_rate=8192, time_length=32, rawdelta_t=-1, \
totalmass=None, inclination=0, phi=0, distance=1.e6, \
verbose=False, debug=False):
"""
#### Assumptions:
### 1. The nr waveform file is uniformly sampled
### 2. wavetypes passed should be :
### CCE , Extrapolated , FiniteRadius , NoGroup, Auto
### Auto : from filename figure out the file type
### 3. filetypes passed should be : ASCII , HDF5 , DataSet
###### About conventions:
### 1. Modes themselves are not amplitude-scaled. Only their time-axis is
### rescaled.
### 2. ...
"""
#{{{
##################################################################
# 0. Ensure inputs are correct
##################################################################
if 'dataset' not in filetype:
if filename is not None and not os.path.exists(filename):
raise IOError("Please provide data file!")
if verbose:
print >>sys.stderr, "\n Reading From Filename=%s" % filename
# Datafile details
self.verbose = verbose
self.debug = debug
self.filename = filename
self.filetype = filetype
self.modeLmax = modeLmax
self.modeLmin = modeLmin
self.skipM0 = skipM0
# Extraction parameters
self.ex_order = ex_order
self.group_name = group_name
# Data analysis parameters
self.sample_rate = sample_rate
self.time_length = time_length
self.dt = 1./self.sample_rate
self.df = 1./self.time_length
self.n = int(self.sample_rate * self.time_length)
if self.verbose:
print >>sys.stderr, "self.sample-rate & time_len = ", \
self.sample_rate, self.time_length
if self.verbose: print >>sys.stderr, "self.n = ", self.n
# Binary parameters
self.totalmass = None
self.inclination = inclination
self.phi = phi
self.distance = distance
if self.verbose:
print >>sys.stderr, " >> Input mass, inc, phi, dist = ", totalmass,\
self.inclination, self.phi, self.distance
sys.stderr.flush()
##################################################################
# 1. Figure out what the data-storage type (wavetype) is
##################################################################
self.wavetype = None
if str(wavetype) in ['CCE', 'Extrapolated', 'FiniteRadius', 'NoGroup']:
self.wavetype = wavetype
elif str(wavetype) == 'Auto':
# Decide from filename the wavetype
fname = self.filename.split('/')[-1]
if 'rhOverM_Asymptotic_GeometricUnits' in fname:
self.wavetype = 'Extrapolated'
elif 'Cce' in fname: self.wavetype = 'CCE'
elif 'FiniteRadii' in fname: self.wavetype = 'FiniteRadius'
elif 'HDF' in self.filetype:
ftmp = h5py.File(self.filename, 'r')
fgrps = [str(grptmp) for grptmp in fgrpstmp]
if 'Y_l2_m2.dat' in fgrps: self.wavetype = 'NoGroup'
#
if self.wavetype == None: raise IOError("Could not figure out wavetype")
if self.verbose: print >>sys.stderr, self.wavetype
sys.stderr.flush()
##################################################################
# 2. Read the data from the file. Read all modes.
##################################################################
#
if 'HDF' in self.filetype:
if self.verbose:
print >>sys.stderr, " > Reading NR data in HDF5 from %s" % self.filename
# Read data file
self.fin = h5py.File(self.filename,'r')
if self.wavetype != 'NoGroup':
grp = self.get_groupname()
print "FOUND GROUP = ", grp, type(grp)
if self.verbose:
print >>sys.stderr, ("From %s out of " % grp), self.fin.keys()
wavedata = self.fin[grp]
else: wavedata = self.fin
# Read modes
self.rawtsamples, self.rawmodes_real, self.rawmodes_imag = {}, {}, {}
for modeL in np.arange( 2, self.modeLmax+1 ):
self.rawtsamples[modeL] = {}
self.rawmodes_real[modeL], self.rawmodes_imag[modeL] = {}, {}
for modeM in np.arange( modeL, -1*modeL-1, -1 ):
if self.skipM0 and modeM==0: continue
mdata = wavedata['Y_l%d_m%d.dat' % (modeL, modeM)].value
if self.verbose: print >> sys.stderr, "Reading %d,%d mode" % (modeL, modeM)
#
ts = mdata[:,0]
hp_int = InterpolatedUnivariateSpline(ts, mdata[:,1])
hc_int = InterpolatedUnivariateSpline(ts, mdata[:,2])
# Hard-coded to re-sample at initial dt
if rawdelta_t <= 0: self.rawdelta_t = ts[1] - ts[0]
else: self.rawdelta_t = rawdelta_t
#
self.rawtsamples[modeL][modeM] = TimeSeries(\
np.arange(ts.min(), ts.max(), self.rawdelta_t),\
delta_t=self.rawdelta_t, epoch=0)
self.rawmodes_real[modeL][modeM] = TimeSeries(\
hp_int( self.rawtsamples[2][2] ),\
delta_t=self.rawdelta_t, epoch=0)
self.rawmodes_imag[modeL][modeM] = TimeSeries(\
hc_int( self.rawtsamples[2][2] ),\
delta_t=self.rawdelta_t, epoch=0)
#
elif 'dataset' in self.filetype:
raise IOError("datasets not supported yet!")
data = self.filename
ts = data[:,0] - data[0,0]
hp_int = InterpolatedUnivariateSpline(ts, data[:,1])
hc_int = InterpolatedUnivariateSpline(ts, data[:,2])
# Hard-coded to re-sample at dt = 1M
if rawdelta_t <= 0: self.rawdelta_t = 1.
else: self.rawdelta_t = rawdelta_t
self.rawtsamples = TimeSeries(arange(0, ts.max()),\
delta_t=self.rawdelta_t, epoch=0)
self.rawhp = TimeSeries(array([hp_int(t) for t in self.rawtsamples]),\
delta_t=self.rawdelta_t, epoch=0)
self.rawhc = TimeSeries(array([hc_int(t) for t in self.rawtsamples]),\
delta_t=self.rawdelta_t, epoch=0)
if self.verbose:
print >>sys.stderr, "times go from %f to %f" % (min(ts), max(ts))
print >>sys.stderr, "rawhp Min = %e, Max = %e" % (min(self.rawhp), max(self.rawhp))
#
elif 'ASCII' in self.filetype:
raise IOError("ASCII datafile not accepted yet!")
if self.verbose: print >>sys.stderr, "Reading NR data in ASCII from %s" % \
self.filename
# Read modes
self.rawtsamples, self.rawmodes_real, self.rawmodes_imag = {}, {}, {}
for modeL in np.arange( 2, self.modeLmax+1 ):
self.rawtsamples[modeL] = {}
self.rawmodes_real[modeL], self.rawmodes_imag[modeL] = {}, {}
for modeM in np.arange( -1*modeL, modeL+1 ):
if self.skipM0 and modeM==0: continue
mdata = np.loadtxt(self.filename % (modeL, modeM))
if self.verbose: print >> sys.stderr, np.shape(mdata)
#
ts = mdata[:,0]
hp_int = InterpolatedUnivariateSpline(ts, mdata[:,1])
hc_int = InterpolatedUnivariateSpline(ts, mdata[:,2])
# Hard-coded to re-sample at initial dt
if rawdelta_t <= 0: self.rawdelta_t = ts[1] - ts[0]
else: self.rawdelta_t = rawdelta_t
#
self.rawtsamples[modeL][modeM] = TimeSeries(\
np.arange(ts.min(), ts.max(), self.rawdelta_t),\
delta_t=self.rawdelta_t, epoch=0)
self.rawmodes_real[modeL][modeM] = TimeSeries(\
array([hp_int(t) for t in self.rawtsamples]),\
delta_t=self.rawdelta_t, epoch=0)
self.rawmodes_imag[modeL][modeM] = TimeSeries(\
array([hc_int(t) for t in self.rawtsamples]),\
delta_t=self.rawdelta_t, epoch=0)
#
self.rescaled_hp = None
self.rescaled_hc = None
if totalmass:
self.rescale_to_totalmass(totalmass)
self.totalmass = totalmass
try: self.fin.close()
except: pass
def get_td_qnm(template=None, delta_t=None, t_lower=None, t_final=None, **kwargs):
"""Return a time domain damped sinusoid.
Parameters
----------
template: object
An object that has attached properties. This can be used to substitute
for keyword arguments. A common example would be a row in an xml table.
f_0 : float
The ringdown-frequency.
tau : float
The damping time of the sinusoid.
t_0 : {0, float}, optional
The starting time of the ringdown.
phi_0 : {0, float}, optional
The initial phase of the ringdown.
Amp : {1, float}, optional
The amplitude of the ringdown (constant for now).
delta_t : {None, float}, optional
The time step used to generate the ringdown.
If None, it will be set to the inverse of the frequency at which the
amplitude is 1/100 of the peak amplitude.
t_lower: {None, float}, optional
The starting time of the output time series.
If None, it will be set to delta_t.
t_final : {None, float}, optional
The ending time of the output time series.
If None, it will be set to the time at which the amplitude is
1/1000 of the peak amplitude.
Returns
-------
hplus: TimeSeries
The plus phase of the ringdown in time domain.
hcross: TimeSeries
The cross phase of the ringdown in time domain.
"""
input_params = props_ringdown(template,**kwargs)
f_0 = input_params['f_0']
tau = input_params['tau']
t_0 = input_params['t_0']
phi_0 = input_params['phi_0']
Amp = input_params['Amp']
if delta_t is None:
delta_t = 1. / qnm_freq_decay(f_0, tau, 1./100)
if t_lower is None:
t_lower = delta_t
kmin = 0
else:
kmin=int(t_lower / delta_t)
if t_final is None:
t_final = qnm_time_decay(tau, 1./1000)
kmax = int(t_final / delta_t)
n = int(t_final / delta_t) + 1
two_pi = 2 * numpy.pi
times = numpy.arange(t_lower, t_final, delta_t)
hp = Amp * numpy.exp(-times/tau) * numpy.cos(two_pi*f_0*times + phi_0)
hc = Amp * numpy.exp(-times/tau) * numpy.sin(two_pi*f_0*times + phi_0)
hplus = TimeSeries(zeros(n), delta_t=delta_t)
hcross = TimeSeries(zeros(n), delta_t=delta_t)
hplus.data[kmin:kmax] = hp
hcross.data[kmin:kmax] = hc
return hplus, hcross
def _get_waveform_from_inspiral(**p):
import lalmetaio
# prefix with 'Inspiral-'
name = p['approximant'][9:]
if name.startswith('EOB'):
p['phase_order'] = -8
params = lalmetaio.SimInspiralTable()
params.waveform = name + string_from_order[p['phase_order']]
params.mass1= p['mass1']
params.mass2= p['mass2']
params.f_lower = p['f_lower']
params.spin1x = p['spin1x']
params.spin1y = p['spin1y']
params.spin1z = p['spin1z']
params.spin2x = p['spin2x']
params.spin2y = p['spin2y']
params.spin2z = p['spin2z']
params.inclination = p['inclination']
params.distance = p['distance']
params.coa_phase = p['coa_phase']
import lalinspiral
guess_length = lalinspiral.FindChirpChirpTime(params.mass1, params.mass2,
params.f_lower, 7)
guess_length = max(guess_length, 3)
params.geocent_end_time = guess_length * 1.5
params.taper = 'TAPER_NONE' #FIXME - either explain or don't hardcode this
bufferl = guess_length * 2
dt = p['delta_t']
df = 1.0 / bufferl
sample_rate = int(1.0 / dt)
epoch = lal.LIGOTimeGPS(0, 0)
N = bufferl * sample_rate
n = N / 2 + 1
resp = FrequencySeries(zeros(n), delta_f=df, epoch=epoch,
dtype=complex64) + 1
out = TimeSeries(zeros(N), delta_t=dt, epoch=epoch, dtype=float32)
outl = out.lal()
outl.sampleUnits = lal.ADCCountUnit
out2 = TimeSeries(zeros(N), delta_t=dt, epoch=epoch, dtype=float32)
outl2 = out.lal()
outl2.sampleUnits = lal.ADCCountUnit
respl = resp.lal()
respl.sampleUnits = lal.DimensionlessUnit
lalinspiral.FindChirpInjectSignals(outl, params, respl)
params.coa_phase -= lal.PI / 4
lalinspiral.FindChirpInjectSignals(outl2, params, respl)
seriesp = TimeSeries(outl.data.data, delta_t=dt,
epoch=epoch - params.geocent_end_time)
seriesc = TimeSeries(outl2.data.data, delta_t=dt,
epoch=epoch - params.geocent_end_time)
return seriesp, seriesc
from pycbc.frame import read_frame
from pycbc.filter import highpass_fir, lowpass_fir
from pycbc.psd import welch, interpolate
from pycbc.types import TimeSeries
import urllib
# Read data and remove low frequency content
fname = 'H-H1_LOSC_4_V2-1126259446-32.gwf'
url = "https://losc.ligo.org/s/events/GW150914/" + fname
urllib.urlretrieve(url, filename=fname)
h1 = highpass_fir(read_frame(fname, 'H1:LOSC-STRAIN'), 15.0, 8)
# Calculate the noise spectrum and whiten
psd = interpolate(welch(h1), 1.0 / 32)
white_strain = (h1.to_frequencyseries() / psd ** 0.5 * psd.delta_f).to_timeseries()
# remove some of the high and low frequencies
smooth = highpass_fir(white_strain, 25, 8)
smooth = lowpass_fir(white_strain, 250, 8)
#strech out and shift the frequency upwards to aid human hearing
fdata = smooth.to_frequencyseries()
fdata.roll(int(1200 / fdata.delta_f))
smooth = TimeSeries(fdata.to_timeseries(), delta_t=1.0/1024)
#Take slice around signal
smooth = smooth[len(smooth)/2 - 1500:len(smooth)/2 + 3000]
smooth.save_to_wav('gw150914_h1_chirp.wav')
def resample_to_delta_t(timeseries, delta_t, method='butterworth'):
"""Resmple the time_series to delta_t
Resamples the TimeSeries instance time_series to the given time step,
delta_t. Only powers of two and real valued time series are supported
at this time. Additional restrictions may apply to particular filter
methods.
Parameters
----------
time_series: TimeSeries
The time series to be resampled
delta_t: float
The desired time step
Returns
-------
Time Series: TimeSeries
A TimeSeries that has been resampled to delta_t.
Raises
------
TypeError:
time_series is not an instance of TimeSeries.
TypeError:
time_series is not real valued
Examples
--------
>>> h_plus_sampled = resample_to_delta_t(h_plus, 1.0/2048)
"""
if not isinstance(timeseries,TimeSeries):
raise TypeError("Can only resample time series")
if timeseries.kind is not 'real':
raise TypeError("Time series must be real")
if timeseries.delta_t == delta_t:
return timeseries * 1
if method == 'butterworth':
lal_data = timeseries.lal()
_resample_func[timeseries.dtype](lal_data, delta_t)
data = lal_data.data.data
elif method == 'ldas':
factor = int(delta_t / timeseries.delta_t)
numtaps = factor * 20 + 1
# The kaiser window has been testing using the LDAS implementation
# and is in the same configuration as used in the original lalinspiral
filter_coefficients = scipy.signal.firwin(numtaps, 1.0 / factor,
window=('kaiser', 5))
# apply the filter and decimate
data = fir_zero_filter(filter_coefficients, timeseries)[::factor]
else:
raise ValueError('Invalid resampling method: %s' % method)
ts = TimeSeries(data, delta_t = delta_t,
dtype=timeseries.dtype,
epoch=timeseries._epoch)
# From the construction of the LDAS FIR filter there will be 10 corrupted samples
# explanation here http://software.ligo.org/docs/lalsuite/lal/group___resample_time_series__c.html
ts.corrupted_samples = 10
return ts
def get_td_qnm(template=None, taper=None, **kwargs):
"""Return a time domain damped sinusoid.
Parameters
----------
template: object
An object that has attached properties. This can be used to substitute
for keyword arguments. A common example would be a row in an xml table.
taper: {None, float}, optional
Tapering at the beginning of the waveform with duration taper * tau.
This option is recommended with timescales taper=1./2 or 1. for
time-domain ringdown-only injections.
The abrupt turn on of the ringdown can cause issues on the waveform
when doing the fourier transform to the frequency domain. Setting
taper will add a rapid ringup with timescale tau/10.
f_0 : float
The ringdown-frequency.
tau : float
The damping time of the sinusoid.
phi : float
The initial phase of the ringdown.
amp : float
The amplitude of the ringdown (constant for now).
delta_t : {None, float}, optional
The time step used to generate the ringdown.
If None, it will be set to the inverse of the frequency at which the
amplitude is 1/1000 of the peak amplitude.
t_final : {None, float}, optional
The ending time of the output time series.
If None, it will be set to the time at which the amplitude is
1/1000 of the peak amplitude.
Returns
-------
hplus: TimeSeries
The plus phase of the ringdown in time domain.
hcross: TimeSeries
The cross phase of the ringdown in time domain.
"""
input_params = props(template, qnm_required_args, **kwargs)
f_0 = input_params.pop('f_0')
tau = input_params.pop('tau')
amp = input_params.pop('amp')
phi = input_params.pop('phi')
# the following may not be in input_params
delta_t = input_params.pop('delta_t', None)
t_final = input_params.pop('t_final', None)
if delta_t is None:
delta_t = 1. / qnm_freq_decay(f_0, tau, 1./1000)
if delta_t < min_dt:
delta_t = min_dt
if t_final is None:
t_final = qnm_time_decay(tau, 1./1000)
kmax = int(t_final / delta_t) + 1
times = numpy.arange(kmax) * delta_t
hp = amp * numpy.exp(-times/tau) * numpy.cos(two_pi*f_0*times + phi)
hc = amp * numpy.exp(-times/tau) * numpy.sin(two_pi*f_0*times + phi)
# If size of tapering window is less than delta_t, do not apply taper.
if taper is None or delta_t > taper*tau:
hplus = TimeSeries(zeros(kmax), delta_t=delta_t)
hcross = TimeSeries(zeros(kmax), delta_t=delta_t)
hplus.data[:kmax] = hp
hcross.data[:kmax] = hc
return hplus, hcross
else:
taper_hp, taper_hc, taper_window, start = apply_taper(delta_t, taper,
f_0, tau, amp, phi)
hplus = TimeSeries(zeros(taper_window+kmax), delta_t=delta_t)
hcross = TimeSeries(zeros(taper_window+kmax), delta_t=delta_t)
hplus.data[:taper_window] = taper_hp
hplus.data[taper_window:] = hp
hplus._epoch = start
hcross.data[:taper_window] = taper_hc
hcross.data[taper_window:] = hc
hcross._epoch = start
return hplus, hcross
def main():
parser = argparse.ArgumentParser()
parser.add_argument('--start',
default=0,
type=int,
help='The index of the first template to generate.')
parser.add_argument('--number-samples',
default=1000,
type=int,
help='The number of samples to generate.')
parser.add_argument(
'--workers',
help=
'The number of processes to spwan. (default: number processes = number available cores)'
)
parser.add_argument('--name',
required=True,
help='The base-name for the output file.')
parser.add_argument(
'--params-config-file',
required=True,
help='The configuration file from which the templates are generated.')
parser.add_argument(
'--network-config-file',
required=True,
help='The config-file specifying the network to use for training.')
parser.add_argument(
'--file-name',
default='{name}-{start}-{stop}-{samples}.hdf',
type=str,
help=
'A formatting string from which the file names are constructed. Available keys are "name", "start", "stop", "samples".'
)
parser.add_argument(
'--detectors',
nargs='+',
default=['H1', 'L1', 'V1'],
help=
'The detectors for which to generate the waveforms. (Detector names as understood by PyCBC)'
)
parser.add_argument(
'--verbose',
default=False,
type=str2bool,
help='Whether or not to print a progress bar. (default: false)')
parser.add_argument(
'--psd-names',
action=MultiDetOptionAction,
help=
'The names (as understood by PyCBC) to use for whitening and noise generation. (Add as det_name1:psd_name1 det_name2:psd_name2)'
)
parser.add_argument(
'--time-shift-name',
default='tc',
help=
'The name of the variable that gives the length of the time-shift to apply to every template'
)
parser.add_argument('--final-duration',
default=1.0,
type=float,
help='The duration of the final template in seconds.')
parser.add_argument(
'--translation',
nargs='+',
action=TranslationAction,
default={},
help=
'Translate the parameter names. (Input as par1:par1new par2:par2new ...)'
)
parser.add_argument(
'--training-data',
type=str2bool,
default=True,
help=
'If true it uses the directory for the training data to store the results. Otherwise the testing data directory will be used.'
)
parser.add_argument(
'--output-vitaminb-params-files',
type=str2bool,
default=False,
help=
'Whether or not to generate the params, bounds and fixed-vals files that are required by VItaminB.'
)
parser.add_argument('--seed',
help='The seed to use to draw waveform-parameters.')
args = parser.parse_args()
stop = args.start + args.number_samples
file_name = args.file_name.format(name=args.name,
start=args.start,
stop=stop,
samples=args.number_samples)
######################
#Convert config files#
######################
#Create .ini-file for PyCBC
config_file = 'tmp_parameter_config.ini'
vitaminb_params_to_pycbc_params(args.params_config_file, config_file)
#Convert .ini-files to vitaminb understandable .json files.
params_file = 'tmp_params.json'
bounds_file = 'tmp_bounds.json'
fixed_vals_file = 'tmp_fixed_vals.json'
tmp_params, tmp_bounds, tmp_fixed = params_files_from_config(
args.params_config_file,
args.network_config_file,
translation=args.translation)
if args.output_vitaminb_params_files:
with open(params_file, 'w') as fp:
json.dump(tmp_params, fp, indent=4)
with open(bounds_file, 'w') as fp:
json.dump(tmp_bounds, fp, indent=4)
with open(fixed_vals_file, 'w') as fp:
json.dump(tmp_fixed, fp, indent=4)
####################
#Generate waveforms#
####################
if args.seed is None:
seed = int(time.time())
else:
seed = int(args.seed)
param_gen = WFParamGenerator(config_file, seed=seed)
params = param_gen.draw_multiple(args.number_samples)
params = field_array_to_dict(params)
try:
params['tc'] = params.pop(args.time_shift_name)
except:
pass
getter = WaveformGetter(variable_params=params,
static_params=param_gen.static,
detectors=args.detectors)
wavs = getter.generate_mp(workers=args.workers, verbose=args.verbose)
try:
params[args.time_shift_name] = params.pop('tc')
except:
pass
#############
#Whiten data#
#############
#TODO: Make this use multiprocessing
psd_names = {key: val for (key, val) in args.psd_names.items()}
for key in wavs.keys():
if key not in psd_names:
if key == 'H1' or key == 'L1':
psd_names[key] = 'aLIGOZeroDetHighPower'
elif key == 'V1':
#psd_names[key] = 'AdVDesignSensitivityP1200087'
psd_names[key] = 'Virgo'
elif key == 'K1':
psd_names[key] = 'KAGRADesignSensitivityT1600593'
flow = getter.static_params['f_lower']
if args.verbose:
bar = progress_tracker(len(wavs) * len(getter),
name='Whitening samples')
white_wavs = {}
psd_cache = NamedPSDCache(list(set(psd_names.values())))
for key in wavs.keys():
white_wavs[key] = []
psd_name = psd_names.get(key)
for wav in wavs[key]:
tmp = TimeSeries(np.zeros(int(8 * wav.sample_rate + len(wav))),
delta_t=wav.delta_t,
epoch=wav.start_time - 4)
tmp.data[int(4 *
wav.sample_rate):int(-4 *
wav.sample_rate)] = wav.data[:]
psd = psd_cache.get_from_timeseries(tmp,
max(flow - 2, 0),
psd_name=psd_names[key])
white_wavs[key].append(
whiten(tmp,
low_freq_cutoff=flow,
max_filter_duration=4.,
psd=psd))
if args.verbose:
bar.iterate()
#############################
#Crop data to correct length#
#############################
time_shifted = {}
final_len = int(args.final_duration / getter.static_params['delta_t'])
if args.verbose:
bar = progress_tracker(len(white_wavs) * len(getter),
name='Applying time shifts')
for key in white_wavs.keys():
time_shifted[key] = []
for i, wav in enumerate(white_wavs[key]):
t0_idx = int((args.final_duration / 2 - float(wav.start_time)) *
wav.sample_rate)
#Pad too short waveforms
if t0_idx < 0:
wav.prepend_zeros(-t0_idx)
t0_idx = 0
time_shifted[key].append(wav[t0_idx:t0_idx + final_len])
if args.verbose:
bar.iterate()
################
#Store the data#
################
#Set the output file location
if args.training_data:
file_loc = os.path.join(tmp_params['train_set_dir'], file_name)
else:
file_loc = os.path.join(tmp_params['test_set_dir'], file_name)
#Ensure that a translation is given for every parameter
translation = args.translation
keys = list(getter.variable_params)
for key in keys:
if key not in translation:
translation[key] = key
#Format the data to store it properly
store_array = np.zeros((len(time_shifted), len(getter), final_len))
for i, key in enumerate(time_shifted.keys()):
for j, dat in enumerate(time_shifted[key]):
store_array[i][j][:] = np.array(dat)[:]
store_array = store_array.transpose(1, 0, 2)
#print(f"Store array shape: {store_array.shape}")
x_data = np.vstack([np.array(params[key]) for key in keys])
x_data = x_data.transpose()
#x_data = x_data.reshape((len(getter), 1, len(keys)))
#Calculate the optimal SNR of all signals
if args.verbose:
bar = progress_tracker(len(time_shifted) * len(getter),
name='Calculating SNRs')
snrs = []
for key in time_shifted.keys():
tmp = []
for wav in time_shifted[key]:
tmp.append(sigma(wav, low_frequency_cutoff=flow))
snrs.append(tmp)
snrs = np.array(snrs)
snrs = snrs.transpose()
#Set some auxiliary data
y_normscale = tmp_params['y_normscale']
tmpkeys = [translation[key] for key in keys]
#Store the data
if args.training_data:
with h5py.File(file_loc, 'w') as fp:
fp.create_dataset('x_data', data=x_data)
fp.create_dataset('y_data_noisefree',
data=store_array *
np.sqrt(getter.static_params['delta_t']))
# fp.create_dataset('y_data_noisefree', data=store_array)
fp.create_dataset('y_data_noisy',
data=store_array +
np.random.normal(size=store_array.shape))
# fp.create_dataset('y_data_noisy', data=store_array+np.random.normal(scale=np.sqrt(1. / getter.static_params['delta_t']), size=store_array.shape))
fp.create_dataset('rand_pars', data=np.array(tmpkeys, dtype='S'))
fp.create_dataset('snrs', data=snrs)
fp.create_dataset('y_normscale', data=y_normscale)
for key, val in tmp_bounds.items():
fp.create_dataset(key, data=val)
else:
for i in range(args.number_samples):
file_loc = os.path.join(
tmp_params['test_set_dir'],
args.file_name.format(name=args.name,
start=args.start + i,
stop=args.start + i + 1,
samples=args.number_samples))
with h5py.File(file_loc, 'w') as fp:
fp.create_dataset('x_data',
data=np.expand_dims(x_data[i], axis=0))
fp.create_dataset('y_data_noisefree',
data=store_array[i] *
np.sqrt(getter.static_params['delta_t']))
# fp.create_dataset('y_data_noisefree', data=store_array[i])
fp.create_dataset('y_data_noisy',
data=store_array[i] +
np.random.normal(size=store_array[i].shape))
# fp.create_dataset('y_data_noisy', data=store_array[i]+np.random.normal(scale=np.sqrt(1. / getter.static_params['delta_t']), size=store_array[i].shape))
fp.create_dataset('rand_pars',
data=np.array(tmpkeys, dtype='S'))
fp.create_dataset('snrs', data=snrs[i])
fp.create_dataset('y_normscale', data=y_normscale)
for key, val in tmp_bounds.items():
fp.create_dataset(key, data=val)
if args.output_vitaminb_params_files:
return params_file, bounds_file, fixed_vals_file
else:
return None
def resample_to_delta_t(timeseries, delta_t, method='butterworth'):
"""Resmple the time_series to delta_t
Resamples the TimeSeries instance time_series to the given time step,
delta_t. Only powers of two and real valued time series are supported
at this time. Additional restrictions may apply to particular filter
methods.
Parameters
----------
time_series: TimeSeries
The time series to be resampled
delta_t: float
The desired time step
Returns
-------
Time Series: TimeSeries
A TimeSeries that has been resampled to delta_t.
Raises
------
TypeError:
time_series is not an instance of TimeSeries.
TypeError:
time_series is not real valued
Examples
--------
>>> h_plus_sampled = resample_to_delta_t(h_plus, 1.0/2048)
"""
if not isinstance(timeseries, TimeSeries):
raise TypeError("Can only resample time series")
if timeseries.kind is not 'real':
raise TypeError("Time series must be real")
if timeseries.delta_t == delta_t:
return timeseries * 1
if method == 'butterworth':
lal_data = timeseries.lal()
_resample_func[timeseries.dtype](lal_data, delta_t)
data = lal_data.data.data
elif method == 'ldas':
factor = int(delta_t / timeseries.delta_t)
if factor == 8:
timeseries = resample_to_delta_t(timeseries,
timeseries.delta_t * 4.0,
method='ldas')
factor = 2
elif factor == 16:
timeseries = resample_to_delta_t(timeseries,
timeseries.delta_t * 4.0,
method='ldas')
factor = 4
elif factor == 32:
timeseries = resample_to_delta_t(timeseries,
timeseries.delta_t * 8.0,
method='ldas')
factor = 4
elif factor == 64:
timeseries = resample_to_delta_t(timeseries,
timeseries.delta_t * 16.0,
method='ldas')
factor = 4
try:
filter_coefficients = LDAS_FIR_LP[factor]
except:
raise ValueError('Unsupported resample factor, %s, given' % factor)
# apply the filter
series = scipy.signal.lfilter(filter_coefficients, 1.0,
timeseries.numpy())
# reverse the time shift caused by the filter
corruption_length = len(filter_coefficients)
data = numpy.zeros(len(timeseries))
data[:len(data) - corruption_length / 2] = series[corruption_length /
2:]
# zero out corrupted region
data[0:corruption_length / 2] = 0
data[len(data) - corruption_length / 2:] = 0
# Decimate the time series
data = data[::factor] * 1
else:
raise ValueError('Invalid resampling method: %s' % method)
return TimeSeries(data,
delta_t=delta_t,
dtype=timeseries.dtype,
epoch=timeseries._epoch)
def setUp(self):
self.Msun = 4.92549095e-6
self.sample_rate = 4096
self.segment_length = 256
self.low_frequency_cutoff = 30.0
# chirp params
self.m1 = 2.0
self.m2 = 2.5
self.del_t = 1.0/self.sample_rate
self.Dl = 40.0
self.iota = 1.0
self.phi_c = 2.0
self.tc_indx = 86*self.sample_rate ## offset from the beginnig of a segment
self.fmax = 1.0/(6.**1.5 *pi *(self.m1+self.m2)*self.Msun)
self.zeta = 1.0
self.thetaS = 0.5
self.phiS = 2.781
self.Fp = 0.5*cos(2.0*self.zeta)*(1.0 + cos(self.thetaS)*cos(self.thetaS))*cos(2.0*self.phiS) - \
sin(2.*self.zeta)*cos(self.thetaS)*sin(2.*self.phiS)
self.Fc = 0.5*sin(2.0*self.zeta)*(1.0 + cos(self.thetaS)*cos(self.thetaS))*cos(2.0*self.phiS) + \
cos(2.*self.zeta)*sin(self.thetaS)*sin(2.*self.phiS)
# params of sin-gaussian
self.Q = 1.e-1
self.om = 200.0*pi*2.0
# use flat psd
self.seg_len_idx = self.segment_length * self.sample_rate
self.psd_len = int(self.seg_len_idx/2+1)
self.Psd = np.ones(self.psd_len)*2.0e-46
# generate waveform and chirp signal
hp, hc = get_td_waveform(approximant="SpinTaylorT5", mass1=self.m1, mass2=self.m2, \
delta_t=self.del_t, f_lower=self.low_frequency_cutoff, distance=self.Dl, \
inclination=self.iota, coa_phase=self.phi_c)
# signal which is a noiseless data
thp = np.zeros(self.seg_len_idx)
thp[self.tc_indx:len(hp)+self.tc_indx] = hp
thc = np.zeros(self.seg_len_idx)
thc[self.tc_indx:len(hc)+self.tc_indx] = hc
fct = 10.0/15.21377
self.sig1 = fct*(self.Fp*thp + self.Fc*thc)
#### template
h = np.zeros(self.seg_len_idx)
h[0:len(hp)] = hp
hpt = TimeSeries(h, self.del_t)
self.htilde = make_frequency_series(hpt)
# generate sin-gaussian signal
time = np.arange(0, len(hp))*self.del_t
Nby2 = int(len(hp)/2)
sngt = np.zeros(len(hp))
for i in range(len(hp)):
sngt[i] = 9.0e-21*exp(-(time[i]-time[Nby2])**2/self.Q)*sin(self.om*time[i])
self.sig2 = np.zeros(self.seg_len_idx)
self.sig2[self.tc_indx:len(sngt)+self.tc_indx] = sngt
def calc_filt_psd_variation(strain, segment, short_segment, psd_long_segment,
psd_duration, psd_stride, psd_avg_method, low_freq,
high_freq):
""" Calculates time series of PSD variability
This function first splits the segment up into 512 second chunks. It
then calculates the PSD over this 512 second. The PSD is used to
to create a filter that is the composition of three filters:
1. Bandpass filter between f_low and f_high.
2. Weighting filter which gives the rough response of a CBC template.
3. Whitening filter.
Next it makes the convolution of this filter with the stretch of data.
This new time series is given to the "mean_square" function, which
computes the mean square of the timeseries within an 8 seconds window,
once per second.
The result, which is the variance of the S/N in that stride for the
Parseval theorem, is then stored in a timeseries.
Parameters
----------
strain : TimeSeries
Input strain time series to estimate PSDs
segment : {float, 8}
Duration of the segments for the mean square estimation in seconds.
short_segment : {float, 0.25}
Duration of the short segments for the outliers removal.
psd_long_segment : {float, 512}
Duration of the long segments for PSD estimation in seconds.
psd_duration : {float, 8}
Duration of FFT segments for long term PSD estimation, in seconds.
psd_stride : {float, 4}
Separation between FFT segments for long term PSD estimation, in
seconds.
psd_avg_method : {string, 'median'}
Method for averaging PSD estimation segments.
low_freq : {float, 20}
Minimum frequency to consider the comparison between PSDs.
high_freq : {float, 480}
Maximum frequency to consider the comparison between PSDs.
Returns
-------
psd_var : TimeSeries
Time series of the variability in the PSD estimation
"""
# Calculate strain precision
if strain.precision == 'single':
fs_dtype = numpy.float32
elif strain.precision == 'double':
fs_dtype = numpy.float64
# Convert start and end times immediately to floats
start_time = numpy.float(strain.start_time)
end_time = numpy.float(strain.end_time)
# Resample the data
strain = resample_to_delta_t(strain, 1.0 / 2048)
srate = int(strain.sample_rate)
# Fix the step for the PSD estimation and the time to remove at the
# edge of the time series.
step = 1.0
strain_crop = 8.0
# Find the times of the long segments
times_long = numpy.arange(
start_time, end_time,
psd_long_segment - 2 * strain_crop - segment + step)
# Set up the empty time series for the PSD variation estimate
ts_duration = end_time - start_time - 2 * strain_crop - segment + 1
psd_var = TimeSeries(zeros(int(numpy.floor(ts_duration / step))),
delta_t=step,
copy=False,
epoch=start_time + strain_crop + segment)
# Create a bandpass filter between low_freq and high_freq
filt = sig.firwin(4 * srate, [low_freq, high_freq],
pass_zero=False,
window='hann',
nyq=srate / 2)
filt.resize(int(psd_duration * srate))
# Fourier transform the filter and take the absolute value to get
# rid of the phase. Save the filter as a frequency series.
filt = abs(rfft(filt))
my_filter = FrequencySeries(filt,
delta_f=1. / psd_duration,
dtype=fs_dtype)
ind = 0
for tlong in times_long:
# Calculate PSD for long segment
if tlong + psd_long_segment <= float(end_time):
astrain = strain.time_slice(tlong, tlong + psd_long_segment)
plong = pycbc.psd.welch(
astrain,
seg_len=int(psd_duration * strain.sample_rate),
seg_stride=int(psd_stride * strain.sample_rate),
avg_method=psd_avg_method)
else:
astrain = strain.time_slice(tlong, end_time)
plong = pycbc.psd.welch(
strain.time_slice(end_time - psd_long_segment, end_time),
seg_len=int(psd_duration * strain.sample_rate),
seg_stride=int(psd_stride * strain.sample_rate),
avg_method=psd_avg_method)
# Make the weighting filter - bandpass, which weight by f^-7/6,
# and whiten. The normalization is chosen so that the variance
# will be one if this filter is applied to white noise which
# already has a variance of one.
freqs = FrequencySeries(plong.sample_frequencies,
delta_f=plong.delta_f,
epoch=plong.epoch,
dtype=fs_dtype)
fweight = freqs**(-7. / 6.) * my_filter / numpy.sqrt(plong)
fweight[0] = 0.
norm = (sum(abs(fweight)**2) / (len(fweight) - 1.))**-0.5
fweight = norm * fweight
fwhiten = numpy.sqrt(2. / srate) / numpy.sqrt(plong)
fwhiten[0] = 0.
full_filt = sig.hann(int(psd_duration * srate)) * numpy.roll(
irfft(fwhiten * fweight),
int(psd_duration / 2) * srate)
# Convolve the filter with long segment of data
wstrain = TimeSeries(sig.fftconvolve(astrain, full_filt, mode='same'),
delta_t=strain.delta_t,
epoch=astrain.start_time)
wstrain = wstrain[int(strain_crop * srate):-int(strain_crop * srate)]
# compute the mean square of the chunk of data
delta_t = wstrain.end_time.gpsSeconds - wstrain.start_time.gpsSeconds
variation = mean_square(wstrain, delta_t, short_segment, segment)
# Store variation value
for i, val in enumerate(variation):
psd_var[ind + i] = val
ind = ind + len(variation)
return psd_var
def bank_chisq_from_filters(tmplt_snr,
tmplt_norm,
bank_snrs,
bank_norms,
tmplt_bank_matches,
indices=None):
""" This function calculates and returns a TimeSeries object containing the
bank veto calculated over a segment.
Parameters
----------
tmplt_snr: TimeSeries
The SNR time series from filtering the segment against the current
search template
tmplt_norm: float
The normalization factor for the search template
bank_snrs: list of TimeSeries
The precomputed list of SNR time series between each of the bank veto
templates and the segment
bank_norms: list of floats
The normalization factors for the list of bank veto templates
(usually this will be the same for all bank veto templates)
tmplt_bank_matches: list of floats
The complex overlap between the search template and each
of the bank templates
indices: {None, Array}, optional
Array of indices into the snr time series. If given, the bank chisq
will only be calculated at these values.
Returns
-------
bank_chisq: TimeSeries of the bank vetos
"""
if indices is not None:
tmplt_snr = Array(tmplt_snr, copy=False)
bank_snrs_tmp = []
for bank_snr in bank_snrs:
bank_snrs_tmp.append(bank_snr.take(indices))
bank_snrs = bank_snrs_tmp
# Initialise bank_chisq as 0s everywhere
bank_chisq = zeros(len(tmplt_snr), dtype=real_same_precision_as(tmplt_snr))
# Loop over all the bank templates
for i in range(len(bank_snrs)):
bank_match = tmplt_bank_matches[i]
if (abs(bank_match) > 0.99):
# Not much point calculating bank_chisquared if the bank template
# is very close to the filter template. Can also hit numerical
# error due to approximations made in this calculation.
# The value of 2 is the expected addition to the chisq for this
# template
bank_chisq += 2.
continue
bank_norm = sqrt((1 - bank_match * bank_match.conj()).real)
bank_SNR = bank_snrs[i] * (bank_norms[i] / bank_norm)
tmplt_SNR = tmplt_snr * (bank_match.conj() * tmplt_norm / bank_norm)
bank_SNR = Array(bank_SNR, copy=False)
tmplt_SNR = Array(tmplt_SNR, copy=False)
bank_chisq += (bank_SNR - tmplt_SNR).squared_norm()
if indices is not None:
return bank_chisq
else:
return TimeSeries(bank_chisq,
delta_t=tmplt_snr.delta_t,
epoch=tmplt_snr.start_time,
copy=False)
def matched_filter_core(template,
data,
psd=None,
low_frequency_cutoff=None,
high_frequency_cutoff=None,
h_norm=None,
out=None,
corr_out=None):
""" Return the complex snr and normalization.
Return the complex snr, along with its associated normalization of the template,
matched filtered against the data.
Parameters
----------
template : TimeSeries or FrequencySeries
The template waveform
data : TimeSeries or FrequencySeries
The strain data to be filtered.
psd : {FrequencySeries}, optional
The noise weighting of the filter.
low_frequency_cutoff : {None, float}, optional
The frequency to begin the filter calculation. If None, begin at the
first frequency after DC.
high_frequency_cutoff : {None, float}, optional
The frequency to stop the filter calculation. If None, continue to the
the nyquist frequency.
h_norm : {None, float}, optional
The template normalization. If none, this value is calculated internally.
out : {None, Array}, optional
An array to use as memory for snr storage. If None, memory is allocated
internally.
corr_out : {None, Array}, optional
An array to use as memory for correlation storage. If None, memory is allocated
internally. If provided, management of the vector is handled externally by the
caller. No zero'ing is done internally.
Returns
-------
snr : TimeSeries
A time series containing the complex snr.
corrrelation: FrequencySeries
A frequency series containing the correlation vector.
norm : float
The normalization of the complex snr.
"""
if corr_out is not None:
_qtilde = corr_out
else:
global _qtilde_t
_qtilde = _qtilde_t
htilde = make_frequency_series(template)
stilde = make_frequency_series(data)
if len(htilde) != len(stilde):
raise ValueError("Length of template and data must match")
N = (len(stilde) - 1) * 2
kmin, kmax = get_cutoff_indices(low_frequency_cutoff,
high_frequency_cutoff, stilde.delta_f, N)
if out is None:
_q = zeros(N, dtype=complex_same_precision_as(data))
elif (len(out) == N) and type(out) is Array and out.kind == 'complex':
_q = out
else:
raise TypeError('Invalid Output Vector: wrong length or dtype')
if corr_out:
pass
elif (_qtilde is None) or (len(_qtilde) !=
N) or _qtilde.dtype != data.dtype:
_qtilde_t = _qtilde = zeros(N, dtype=complex_same_precision_as(data))
else:
_qtilde.clear()
correlate(htilde[kmin:kmax], stilde[kmin:kmax], _qtilde[kmin:kmax])
if psd is not None:
if isinstance(psd, FrequencySeries):
if psd.delta_f == stilde.delta_f:
_qtilde[kmin:kmax] /= psd[kmin:kmax]
else:
raise TypeError("PSD delta_f does not match data")
else:
raise TypeError("PSD must be a FrequencySeries")
ifft(_qtilde, _q)
if h_norm is None:
h_norm = sigmasq(htilde, psd, low_frequency_cutoff,
high_frequency_cutoff)
norm = (4.0 * stilde.delta_f) / sqrt(h_norm)
delta_t = 1.0 / (N * stilde.delta_f)
return (TimeSeries(_q, epoch=stilde._epoch, delta_t=delta_t, copy=False),
FrequencySeries(_qtilde,
epoch=stilde._epoch,
delta_f=htilde.delta_f,
copy=False), norm)
def do_test(self, n_ifos, n_ifos_followup):
# choose a random selection of interferometers
# n_ifos will be used to generate the simulated trigger
# n_ifos_followup will be used as followup-only
all_ifos = random.sample(self.possible_ifos, n_ifos + n_ifos_followup)
trig_ifos = all_ifos[0:n_ifos]
results = {
'foreground/stat': np.random.uniform(4, 20),
'foreground/ifar': np.random.uniform(0.01, 1000)
}
followup_data = {}
for ifo in all_ifos:
offset = 10000 + np.random.uniform(-0.02, 0.02)
amplitude = np.random.uniform(4, 20)
# generate a mock SNR time series with a peak
n = 201
dt = 1. / 2048.
t = np.arange(n) * dt
t_peak = dt * n / 2
snr = np.exp(-(t - t_peak)**2 * 3e-3**-2) * amplitude
snr_series = TimeSeries((snr + 1j * 0).astype(np.complex64),
delta_t=dt,
epoch=offset)
# generate a mock PSD
psd_samples = np.random.exponential(size=1024)
psd = FrequencySeries(psd_samples, delta_f=1.)
# fill in the various fields
if ifo in trig_ifos:
base = 'foreground/' + ifo + '/'
results[base + 'end_time'] = t_peak + offset
results[base + 'snr'] = amplitude
results[base + 'sigmasq'] = np.random.uniform(1e6, 2e6)
followup_data[ifo] = {'snr_series': snr_series, 'psd': psd}
for ifo, k in itertools.product(trig_ifos, self.template):
results['foreground/' + ifo + '/' + k] = self.template[k]
kwargs = {
'psds': {ifo: followup_data[ifo]['psd']
for ifo in all_ifos},
'low_frequency_cutoff': 20.,
'followup_data': followup_data
}
coinc = SingleCoincForGraceDB(trig_ifos, results, **kwargs)
tempdir = tempfile.mkdtemp()
coinc_file_name = os.path.join(tempdir, 'coinc.xml.gz')
if GraceDb is not None:
# pretend to upload the event to GraceDB.
# The upload will fail, but it should not raise an exception
# and it should still leave the event file around
coinc.upload(coinc_file_name,
gracedb_server='localhost',
testing=True)
else:
# no GraceDb module, so just save the coinc file
coinc.save(coinc_file_name)
# read back and check the coinc document
read_coinc = ligolw_utils.load_filename(coinc_file_name,
verbose=False,
contenthandler=ContentHandler)
single_table = table.get_table(read_coinc,
lsctables.SnglInspiralTable.tableName)
self.assertEqual(len(single_table), len(all_ifos))
coinc_table = table.get_table(read_coinc,
lsctables.CoincInspiralTable.tableName)
self.assertEqual(len(coinc_table), 1)
# make sure lalseries can read the PSDs
psd_doc = ligolw_utils.load_filename(
coinc_file_name,
verbose=False,
contenthandler=lalseries.PSDContentHandler)
psd_dict = lalseries.read_psd_xmldoc(psd_doc)
self.assertEqual(set(psd_dict.keys()), set(all_ifos))
shutil.rmtree(tempdir)
def apply(self, strain, detector_name, f_lower=None, distance_scale=1):
"""Add injections (as seen by a particular detector) to a time series.
Parameters
----------
strain : TimeSeries
Time series to inject signals into, of type float32 or float64.
detector_name : string
Name of the detector used for projecting injections.
f_lower : {None, float}, optional
Low-frequency cutoff for injected signals. If None, use value
provided by each injection.
distance_scale: {1, foat}, optional
Factor to scale the distance of an injection with. The default is
no scaling.
Returns
-------
None
Raises
------
TypeError
For invalid types of `strain`.
"""
if not strain.dtype in (float32, float64):
raise TypeError("Strain dtype must be float32 or float64, not " \
+ str(strain.dtype))
lalstrain = strain.lal()
detector = Detector(detector_name)
earth_travel_time = lal.REARTH_SI / lal.C_SI
t0 = float(strain.start_time) - earth_travel_time
t1 = float(strain.end_time) + earth_travel_time
# pick lalsimulation tapering function
taper = taper_func_map[strain.dtype]
# pick lalsimulation injection function
add_injection = injection_func_map[strain.dtype]
for inj in self.table:
# roughly estimate if the injection may overlap with the segment
end_time = inj.get_time_geocent()
#CHECK: This is a hack (10.0s); replace with an accurate estimate
inj_length = 10.0
eccentricity = 0.0
polarization = 0.0
start_time = end_time - 2 * inj_length
if end_time < t0 or start_time > t1:
continue
# compute the waveform time series
hp, hc = sim.SimBurstSineGaussian(float(inj.q),
float(inj.frequency),float(inj.hrss),float(eccentricity),
float(polarization),float(strain.delta_t))
hp = TimeSeries(hp.data.data[:], delta_t=hp.deltaT, epoch=hp.epoch)
hc = TimeSeries(hc.data.data[:], delta_t=hc.deltaT, epoch=hc.epoch)
hp._epoch += float(end_time)
hc._epoch += float(end_time)
if float(hp.start_time) > t1:
continue
# compute the detector response, taper it if requested
# and add it to the strain
#signal = detector.project_wave(
# hp, hc, inj.longitude, inj.latitude, inj.polarization)
signal_lal = hp.astype(strain.dtype).lal()
if taper_map['TAPER_NONE'] is not None:
taper(signal_lal.data, taper_map['TAPER_NONE'])
add_injection(lalstrain, signal_lal, None)
strain.data[:] = lalstrain.data.data[:]
def get_waveform(approximant,
phase_order,
amplitude_order,
spin_order,
template_params,
start_frequency,
sample_rate,
length,
datafile=None,
verbose=False):
#{{{
print("IN hERE")
delta_t = 1. / sample_rate
delta_f = 1. / length
filter_N = int(length)
filter_n = filter_N / 2 + 1
if approximant in fd_approximants() and 'Eccentric' not in approximant:
print("NORMAL FD WAVEFORM for", approximant)
delta_f = sample_rate / length
hplus, hcross = get_fd_waveform(template_params,
approximant=approximant,
spin_order=spin_order,
phase_order=phase_order,
delta_f=delta_f,
f_lower=start_frequency,
amplitude_order=amplitude_order)
elif approximant in td_approximants() and 'Eccentric' not in approximant:
print("NORMAL TD WAVEFORM for", approximant)
hplus, hcross = get_td_waveform(template_params,
approximant=approximant,
spin_order=spin_order,
phase_order=phase_order,
delta_t=1.0 / sample_rate,
f_lower=start_frequency,
amplitude_order=amplitude_order)
elif 'EccentricIMR' in approximant:
#{{{
# Legacy support
import sys
sys.path.append('/home/kuma/grav/kuma/src/Eccentric_IMR/Codes/Python/')
import EccentricIMR as Ecc
try:
mass1 = getattr(template_params, 'mass1')
mass2 = getattr(template_params, 'mass2')
except:
raise RuntimeError("template_params does not have mass1 or mass2!")
try:
ecc = getattr(template_params, 'alpha1')
if 'E0' in approximant: ecc = 0
anom = getattr(template_params, 'alpha2')
inc = getattr(template_params, 'inclination')
rtrans = getattr(template_params, 'alpha')
beta = 0
except:
raise RuntimeError(\
"template_params does not have alpha{,1,2} or inclination")
tol = 1.e-16
fmin = start_frequency
sample_rate = sample_rate
#
print(" Using phase order: %d" % phase_order, file=sys.stdout)
sys.stdout.flush()
hplus, hcross = Ecc.generate_eccentric_waveform(mass1, mass2,\
ecc, anom, inc, beta,\
tol,\
r_transition=rtrans,\
phase_order=phase_order,\
fmin=fmin,\
sample_rate=sample_rate,\
inspiral_only=False)
#}}}
elif 'EccentricInspiral' in approximant:
#{{{
# Legacy support
import sys
sys.path.append('/home/kuma/grav/kuma/src/Eccentric_IMR/Codes/Python/')
import EccentricIMR as Ecc
try:
mass1 = getattr(template_params, 'mass1')
mass2 = getattr(template_params, 'mass2')
except:
raise RuntimeError("template_params does not have mass1 or mass2!")
try:
ecc = getattr(template_params, 'alpha1')
if 'E0' in approximant: ecc = 0
anom = getattr(template_params, 'alpha2')
inc = getattr(template_params, 'inclination')
beta = getattr(template_params, 'alpha')
except:
raise RuntimeError(\
"template_params does not have alpha{,1,2} or inclination")
tol = 1.e-16
fmin = start_frequency
sample_rate = sample_rate
#
hplus, hcross = Ecc.generate_eccentric_waveform(mass1, mass2,\
ecc, anom, inc, beta,\
tol,\
phase_order=phase_order,\
fmin=fmin,\
sample_rate=sample_rate,\
inspiral_only=True)
#}}}
elif 'EccentricFD' in approximant:
#{{{
# Legacy support
import lalsimulation as ls
import lal
delta_f = sample_rate / length
try:
mass1 = getattr(template_params, 'mass1')
mass2 = getattr(template_params, 'mass2')
except:
raise RuntimeError("template_params does not have mass1 or mass2!")
try:
ecc = getattr(template_params, 'alpha1')
if 'E0' in approximant: ecc = 0
anom = getattr(template_params, 'alpha2')
inc = getattr(template_params, 'inclination')
except:
raise RuntimeError(\
"template_params does not have alpha{1,2} or inclination")
eccPar = ls.SimInspiralCreateTestGRParam("inclination_azimuth", inc)
ls.SimInspiralAddTestGRParam(eccPar, "e_min", ecc)
fmin = start_frequency
fmax = sample_rate / 2
#
thp, thc = ls.SimInspiralChooseFDWaveform(0, delta_f,\
mass1*lal.MSUN_SI, mass2*lal.MSUN_SI,\
0,0,0,0,0,0,\
fmin, fmax, 0, 1.e6 * lal.PC_SI,\
inc, 0, 0, None, eccPar, -1, 7, ls.EccentricFD)
hplus = FrequencySeries(thp.data.data[:],
delta_f=thp.deltaF,
epoch=thp.epoch)
hcross = FrequencySeries(thc.data.data[:],
delta_f=thc.deltaF,
epoch=thc.epoch)
#}}}
elif 'FromDataFile' in approximant:
#{{{
# Legacy support
if not os.path.exists(datafile):
raise IOError("File %s not found!" % datafile)
if verbose:
print("Reading from data file %s" % datafile)
# Figure out waveform parameters from filename
#q_value, M_value, w_value, _, _ = EA.get_q_m_e_pn_o_from_filename(datafile)
q_value, M_value, w_value = EA.get_q_m_e_from_filename(datafile)
# Read data, down-sample (assume data file is more finely sampled than
# needed, i.e. interpolation is NOT supported, nor will be)
data = np.loadtxt(datafile)
dt = data[1, 0] - data[0, 0]
delta_t = 1. / sample_rate
downsample_ratio = delta_t / dt
if not approx_equal(downsample_ratio, np.int(downsample_ratio)):
raise RuntimeError(
"Cannot handling resampling at a fractional factor = %e" %
downsample_ratio)
elif verbose:
print("Downsampling by a factor of %d" % int(downsample_ratio))
h_real = TimeSeries(data[::int(downsample_ratio), 1] / DYN_RANGE_FAC,
delta_t=delta_t)
h_imag = TimeSeries(data[::int(downsample_ratio), 2] / DYN_RANGE_FAC,
delta_t=delta_t)
if verbose:
print("max, min,len of h_real = ", max(h_real.data),
min(h_real.data), len(h_real.data))
# Compute Strain
tmplt_pars = template_params
wav = generate_detector_strain(tmplt_pars, h_real, h_imag)
wav = extend_waveform_TimeSeries(wav, filter_N)
# Return TimeSeries with (m1, m2, w_value)
m1, m2 = mtotal_eta_to_mass1_mass2(M_value,
q_value / (1. + q_value)**2)
htilde = make_frequency_series(wav)
htilde = extend_waveform_FrequencySeries(htilde, filter_n)
if verbose:
print("ISNAN(htilde from file) = ", np.any(np.isnan(htilde.data)))
return htilde, [m1, m2, w_value, dt]
#}}}
else:
raise IOError(".. APPROXIMANT %s not found.." % approximant)
##
hvec = hplus
htilde = make_frequency_series(hvec)
htilde = extend_waveform_FrequencySeries(htilde, filter_n)
#
print("type of hplus, hcross = ", type(hplus.data), type(hcross.data))
if any(isnan(hplus.data)) or any(isnan(hcross.data)):
print("..### %s hplus or hcross have NANS!!" % approximant)
#
if any(isinf(hplus.data)) or any(isinf(hcross.data)):
print("..### %s hplus or hcross have INFS!!" % approximant)
#
if any(isnan(htilde.data)):
print("..### %s Fourier transform htilde has NANS!!" % approximant)
#
if any(isinf(htilde.data)):
print("..### %s Fourier transform htilde has INFS!!" % approximant)
#
return htilde
def resample_to_delta_t(timeseries, delta_t, method='butterworth'):
"""Resmple the time_series to delta_t
Resamples the TimeSeries instance time_series to the given time step,
delta_t. Only powers of two and real valued time series are supported
at this time. Additional restrictions may apply to particular filter
methods.
Parameters
----------
time_series: TimeSeries
The time series to be resampled
delta_t: float
The desired time step
Returns
-------
Time Series: TimeSeries
A TimeSeries that has been resampled to delta_t.
Raises
------
TypeError:
time_series is not an instance of TimeSeries.
TypeError:
time_series is not real valued
Examples
--------
>>> h_plus_sampled = resample_to_delta_t(h_plus, 1.0/2048)
"""
if not isinstance(timeseries,TimeSeries):
raise TypeError("Can only resample time series")
if timeseries.kind is not 'real':
raise TypeError("Time series must be real")
if timeseries.delta_t == delta_t:
return timeseries * 1
if method == 'butterworth':
lal_data = timeseries.lal()
_resample_func[timeseries.dtype](lal_data, delta_t)
data = lal_data.data.data
elif method == 'ldas':
factor = int(delta_t / timeseries.delta_t)
numtaps = factor * 20 + 1
# The kaiser window has been testing using the LDAS implementation
# and is in the same configuration as used in the original lalinspiral
filter_coefficients = scipy.signal.firwin(numtaps, 1.0 / factor,
window=('kaiser', 5))
# apply the filter and decimate
data = fir_zero_filter(filter_coefficients, timeseries)[::factor]
else:
raise ValueError('Invalid resampling method: %s' % method)
ts = TimeSeries(data, delta_t = delta_t,
dtype=timeseries.dtype,
epoch=timeseries._epoch)
# From the construction of the LDAS FIR filter there will be 10 corrupted samples
# explanation here http://software.ligo.org/docs/lalsuite/lal/group___resample_time_series__c.html
ts.corrupted_samples = 10
return ts
def blend(hin, mm, sample, time, t_opt, WinID=-1):
# Only dealing with real part, don't do hc calculations
# t_opt is length-5 array describing multiples of mm
# Returns length-5 array of TimeSeries (1 per blending)
#{{{
hp0, hc0 = hin.rescale_to_totalmass(mm)
hp0._epoch = hc0._epoch = 0
amp = TimeSeries(np.sqrt(hp0**2 + hc0**2), copy=True, delta_t=hp0.delta_t)
max_a, max_a_index = amp.abs_max_loc()
print("\n\n In blend:\nTotal Mass = %f, len(hp0,hc0) = %d, %d = %f s" %\
(mm, len(hp0), len(hc0), hp0.sample_times[-1]-hp0.sample_times[0]))
print("Waveform max = %e, located at %d" % (max_a, max_a_index))
#amp_after_peak = amp
#amp_after_peak[:max_a_index] = 0
mtsun = lal.MTSUN_SI
amp_after_peak = amp[max_a_index:]
iA, vA = min(enumerate(amp_after_peak),
key=lambda x: abs(x[1] - 0.01 * max_a))
iA += max_a_index
#iA, vA = min(enumerate(amp_after_peak),key=lambda x:abs(x[1]-0.01*max_a))
iB, vB = min(enumerate(amp_after_peak),
key=lambda x: abs(x[1] - 0.1 * max_a))
iB += max_a_index
if iA <= max_a_index:
print("iA = %d, iB = %d, vA = %e, vB = %e" % (iA, iB, vA, vB),
file=sys.stdout)
sys.stdout.flush()
raise RuntimeError("Couldnt find amplitude threshold time iA")
# do something
#fout = open('hpdump.dat','w+')
#for i in range( len(amp) ):
# if i > max_a_index and amp[i] == 0: break
# fout.write('%e\t%e\n' % (amp.sample_times[i],amp[i]))
#fout.close()
# Find the point the hard way
target_amp = max_a * 0.01
tmp_data = amp.data
for idx in range(max_a_index, len(amp)):
if tmp_data[idx] < target_amp: break
iA = idx
print("Newfound iA = %d" % iA)
# Yet another way
amp_after_peak = amp[max_a_index:]
iA, vA = min(enumerate(amp_after_peak),
key=lambda x: abs(x[1] - 0.01 * max_a))
iA += max_a_index
print("Newfound iA another way = %d" % iA)
raise RuntimeError("Had to find amplitude threshold the hard way")
if iB <= max_a_index:
raise RuntimeError("Couldnt find amplitude threshold time iB")
# this doesn't happen yet
pass
print("NEW: iA = %d, iB = %d, vA = %e, vB = %e" % (iA, iB, vA, vB))
t = [
[
t_opt[0] * mm, 500 * mm, hp0.sample_times.data[iA] / mtsun,
hp0.sample_times.data[iA] / mtsun + t_opt[3] * mm
], # Prayush's E
[
t_opt[0] * mm, t_opt[1] * mm, hp0.sample_times.data[iA] / mtsun,
hp0.sample_times.data[iA] / mtsun + t_opt[3] * mm
],
[
t_opt[0] * mm, t_opt[1] * mm, hp0.sample_times.data[iB] / mtsun,
hp0.sample_times.data[iB] / mtsun + t_opt[4] * mm
],
[
t_opt[0] * mm, t_opt[2] * mm, hp0.sample_times.data[iA] / mtsun,
hp0.sample_times.data[iA] / mtsun + t_opt[3] * mm
],
[
t_opt[0] * mm, t_opt[2] * mm, hp0.sample_times.data[iB] / mtsun,
hp0.sample_times.data[iB] / mtsun + t_opt[4] * mm
]
]
hphc = []
hphc.append(hp0)
for i in range(len(t)):
if (WinID >= 0 and WinID < len(t)) and i != WinID: continue
print("Testing window with t = ", t[i])
hphc.append(
hin.blending_function(hp0=hp0,
t=t[i],
sample_rate=sample,
time_length=time))
print("No of blending windows being tested = %d" % (len(hphc) - 1))
return hphc
def filter_zpk(timeseries, z, p, k):
"""Return a new timeseries that was filtered with a zero-pole-gain filter.
The transfer function in the s-domain looks like:
.. math::
\\frac{H(s) = (s - s_1) * (s - s_3) * ... * (s - s_n)}{(s - s_2) * (s - s_4) * ... * (s - s_m)}, m >= n
The zeroes, and poles entered in Hz are converted to angular frequency,
along the imaginary axis in the s-domain s=i*omega. Then the zeroes, and
poles are bilinearly transformed via:
.. math::
z(s) = \\frac{(1 + s*T/2)}{(1 - s*T/2)}
Where z is the z-domain value, s is the s-domain value, and T is the
sampling period. After the poles and zeroes have been bilinearly
transformed, then the second-order sections are found and filter the data
using scipy.
Parameters
----------
timeseries: TimeSeries
The TimeSeries instance to be filtered.
z: array
Array of zeros to include in zero-pole-gain filter design.
In units of Hz.
p: array
Array of poles to include in zero-pole-gain filter design.
In units of Hz.
k: float
Gain to include in zero-pole-gain filter design. This gain is a
constant multiplied to the transfer function.
Returns
-------
Time Series: TimeSeries
A new TimeSeries that has been filtered.
Examples
--------
To apply a 5 zeroes at 100Hz, 5 poles at 1Hz, and a gain of 1e-10 filter
to a TimeSeries instance, do:
>>> filtered_data = zpk_filter(timeseries, [100]*5, [1]*5, 1e-10)
"""
# sanity check type
if not isinstance(timeseries, TimeSeries):
raise TypeError("Can only filter TimeSeries instances.")
# sanity check casual filter
degree = len(p) - len(z)
if degree < 0:
raise TypeError("May not have more zeroes than poles. \
Filter is not casual.")
# cast zeroes and poles as arrays and gain as a float
z = np.array(z)
p = np.array(p)
k = float(k)
# put zeroes and poles in the s-domain
# convert from frequency to angular frequency
z *= -2 * np.pi
p *= -2 * np.pi
# get denominator of bilinear transform
fs = 2.0 * timeseries.sample_rate
# zeroes in the z-domain
z_zd = (1 + z / fs) / (1 - z / fs)
# any zeros that were at infinity are moved to the Nyquist frequency
z_zd = z_zd[np.isfinite(z_zd)]
z_zd = np.append(z_zd, -np.ones(degree))
# poles in the z-domain
p_zd = (1 + p / fs) / (1 - p / fs)
# gain change in z-domain
k_zd = k * np.prod(fs - z) / np.prod(fs - p)
# get second-order sections
sos = zpk2sos(z_zd, p_zd, k_zd)
# filter
filtered_data = sosfilt(sos, timeseries.numpy())
return TimeSeries(filtered_data,
delta_t=timeseries.delta_t,
dtype=timeseries.dtype,
epoch=timeseries._epoch)
def get_td_qnm(template=None, **kwargs):
"""Return a time domain damped sinusoid.
Parameters
----------
template: object
An object that has attached properties. This can be used to substitute
for keyword arguments. A common example would be a row in an xml table.
f_0 : float
The ringdown-frequency.
tau : float
The damping time of the sinusoid.
phi_0 : {0, float}, optional
The initial phase of the ringdown.
amp : {1, float}, optional
The amplitude of the ringdown (constant for now).
delta_t : {None, float}, optional
The time step used to generate the ringdown.
If None, it will be set to the inverse of the frequency at which the
amplitude is 1/1000 of the peak amplitude.
t_final : {None, float}, optional
The ending time of the output time series.
If None, it will be set to the time at which the amplitude is
1/1000 of the peak amplitude.
Returns
-------
hplus: TimeSeries
The plus phase of the ringdown in time domain.
hcross: TimeSeries
The cross phase of the ringdown in time domain.
"""
input_params = props_ringdown(template,**kwargs)
# get required args
try:
f_0 = input_params['f_0']
except KeyError:
raise ValueError('f_0 is required')
try:
tau = input_params['tau']
except KeyError:
raise ValueError('tau is required')
# get optional args
# the following have defaults, and so will be populated
phi_0 = input_params.pop('phi_0')
amp = input_params.pop('amp')
# the following may not be in input_params
delta_t = input_params.pop('delta_t', None)
t_final = input_params.pop('t_final', None)
if delta_t is None:
delta_t = 1. / qnm_freq_decay(f_0, tau, 1./1000)
if t_final is None:
t_final = qnm_time_decay(tau, 1./1000)
kmax = int(t_final / delta_t) + 1
two_pi = 2 * numpy.pi
times = numpy.arange(kmax)*delta_t
hp = amp * numpy.exp(-times/tau) * numpy.cos(two_pi*f_0*times + phi_0)
hc = amp * numpy.exp(-times/tau) * numpy.sin(two_pi*f_0*times + phi_0)
hplus = TimeSeries(zeros(kmax), delta_t=delta_t)
hcross = TimeSeries(zeros(kmax), delta_t=delta_t)
hplus.data[:kmax] = hp
hcross.data[:kmax] = hc
return hplus, hcross
def get_td_qnm(template=None, taper=None, **kwargs):
"""Return a time domain damped sinusoid.
Parameters
----------
template: object
An object that has attached properties. This can be used to substitute
for keyword arguments. A common example would be a row in an xml table.
taper: {None, float}, optional
Tapering at the beginning of the waveform with duration taper * tau.
This option is recommended with timescales taper=1./2 or 1. for
time-domain ringdown-only injections.
The abrupt turn on of the ringdown can cause issues on the waveform
when doing the fourier transform to the frequency domain. Setting
taper will add a rapid ringup with timescale tau/10.
f_0 : float
The ringdown-frequency.
tau : float
The damping time of the sinusoid.
amp : float
The amplitude of the ringdown (constant for now).
phi : float
The initial phase of the ringdown. Should also include the information
from the azimuthal angle (phi_0 + m*Phi)
inclination : {None, float}, optional
Inclination of the system in radians for the spherical harmonics.
l : {2, int}, optional
l mode for the spherical harmonics. Default is l=2.
m : {2, int}, optional
m mode for the spherical harmonics. Default is m=2.
delta_t : {None, float}, optional
The time step used to generate the ringdown.
If None, it will be set to the inverse of the frequency at which the
amplitude is 1/1000 of the peak amplitude.
t_final : {None, float}, optional
The ending time of the output time series.
If None, it will be set to the time at which the amplitude is
1/1000 of the peak amplitude.
Returns
-------
hplus: TimeSeries
The plus phase of the ringdown in time domain.
hcross: TimeSeries
The cross phase of the ringdown in time domain.
"""
input_params = props(template, qnm_required_args, **kwargs)
f_0 = input_params.pop('f_0')
tau = input_params.pop('tau')
amp = input_params.pop('amp')
phi = input_params.pop('phi')
# the following may not be in input_params
inc = input_params.pop('inclination', None)
l = input_params.pop('l', 2)
m = input_params.pop('m', 2)
delta_t = input_params.pop('delta_t', None)
t_final = input_params.pop('t_final', None)
if not delta_t:
delta_t = 1. / qnm_freq_decay(f_0, tau, 1./1000)
if delta_t < min_dt:
delta_t = min_dt
if not t_final:
t_final = qnm_time_decay(tau, 1./1000)
kmax = int(t_final / delta_t) + 1
times = numpy.arange(kmax) * delta_t
if inc is not None:
Y_plus, Y_cross = spher_harms(l, m, inc)
else:
Y_plus, Y_cross = 1, 1
hplus = amp * Y_plus * numpy.exp(-times/tau) * \
numpy.cos(two_pi*f_0*times + phi)
hcross = amp * Y_cross * numpy.exp(-times/tau) * \
numpy.sin(two_pi*f_0*times + phi)
if taper and delta_t < taper*tau:
taper_window = int(taper*tau/delta_t)
kmax += taper_window
outplus = TimeSeries(zeros(kmax), delta_t=delta_t)
outcross = TimeSeries(zeros(kmax), delta_t=delta_t)
# If size of tapering window is less than delta_t, do not apply taper.
if not taper or delta_t > taper*tau:
outplus.data[:kmax] = hplus
outcross.data[:kmax] = hcross
return outplus, outcross
else:
taper_hp, taper_hc = apply_taper(delta_t, taper, f_0, tau, amp, phi,
l, m, inc)
start = - taper * tau
outplus.data[:taper_window] = taper_hp
outplus.data[taper_window:] = hplus
outcross.data[:taper_window] = taper_hc
outcross.data[taper_window:] = hcross
outplus._epoch, outcross._epoch = start, start
return outplus, outcross
def apply(self, strain, detector_name, f_lower=None, distance_scale=1,
simulation_ids=None):
"""Add injections (as seen by a particular detector) to a time series.
Parameters
----------
strain : TimeSeries
Time series to inject signals into, of type float32 or float64.
detector_name : string
Name of the detector used for projecting injections.
f_lower : {None, float}, optional
Low-frequency cutoff for injected signals. If None, use value
provided by each injection.
distance_scale: {1, float}, optional
Factor to scale the distance of an injection with. The default is
no scaling.
simulation_ids: iterable, optional
If given, only inject signals with the given simulation IDs.
Returns
-------
None
Raises
------
TypeError
For invalid types of `strain`.
"""
if not strain.dtype in (float32, float64):
raise TypeError("Strain dtype must be float32 or float64, not " \
+ str(strain.dtype))
lalstrain = strain.lal()
detector = Detector(detector_name)
earth_travel_time = lal.REARTH_SI / lal.C_SI
t0 = float(strain.start_time) - earth_travel_time
t1 = float(strain.end_time) + earth_travel_time
# pick lalsimulation injection function
add_injection = injection_func_map[strain.dtype]
injections = self.table
if simulation_ids:
injections = [inj for inj in injections \
if inj.simulation_id in simulation_ids]
for inj in injections:
if f_lower is None:
f_l = inj.f_lower
else:
f_l = f_lower
if inj.numrel_data != None and inj.numrel_data != "":
# performing NR waveform injection
# reading Hp and Hc from the frame files
swigrow = self.getswigrow(inj)
import lalinspiral
Hp, Hc = lalinspiral.NRInjectionFromSimInspiral(swigrow,
strain.delta_t)
# converting to pycbc timeseries
hp = TimeSeries(Hp.data.data[:], delta_t=Hp.deltaT,
epoch=Hp.epoch)
hc = TimeSeries(Hc.data.data[:], delta_t=Hc.deltaT,
epoch=Hc.epoch)
hp /= distance_scale
hc /= distance_scale
end_time = float(hp.get_end_time())
start_time = float(hp.get_start_time())
if end_time < t0 or start_time > t1:
continue
else:
# roughly estimate if the injection may overlap with the segment
end_time = inj.get_time_geocent()
inj_length = sim.SimInspiralTaylorLength(
strain.delta_t, inj.mass1 * lal.MSUN_SI,
inj.mass2 * lal.MSUN_SI, f_l, 0)
start_time = end_time - 2 * inj_length
if end_time < t0 or start_time > t1:
continue
name, phase_order = legacy_approximant_name(inj.waveform)
# compute the waveform time series
hp, hc = get_td_waveform(
inj, approximant=name, delta_t=strain.delta_t,
phase_order=phase_order,
f_lower=f_l, distance=inj.distance * distance_scale,
**self.extra_args)
hp._epoch += float(end_time)
hc._epoch += float(end_time)
if float(hp.start_time) > t1:
continue
# compute the detector response, taper it if requested
# and add it to the strain
signal = detector.project_wave(
hp, hc, inj.longitude, inj.latitude, inj.polarization)
# the taper_timeseries function converts to a LAL TimeSeries
signal = signal.astype(strain.dtype)
signal_lal = wfutils.taper_timeseries(signal, inj.taper, return_lal=True)
add_injection(lalstrain, signal_lal, None)
strain.data[:] = lalstrain.data.data[:]
def get_td_from_freqtau(template=None, taper=None, **kwargs):
"""Return time domain ringdown with all the modes specified.
Parameters
----------
template: object
An object that has attached properties. This can be used to substitute
for keyword arguments. A common example would be a row in an xml table.
taper: {None, float}, optional
Tapering at the beginning of the waveform with duration taper * tau.
This option is recommended with timescales taper=1./2 or 1. for
time-domain ringdown-only injections.
The abrupt turn on of the ringdown can cause issues on the waveform
when doing the fourier transform to the frequency domain. Setting
taper will add a rapid ringup with timescale tau/10.
Each mode and overtone will have a different taper depending on its tau,
the final taper being the superposition of all the tapers.
lmns : list
Desired lmn modes as strings (lm modes available: 22, 21, 33, 44, 55).
The n specifies the number of overtones desired for the corresponding
lm pair (maximum n=8).
Example: lmns = ['223','331'] are the modes 220, 221, 222, and 330
f_lmn: float
Central frequency of the lmn overtone, as many as number of modes.
tau_lmn: float
Damping time of the lmn overtone, as many as number of modes.
amp220 : float
Amplitude of the fundamental 220 mode.
amplmn : float
Fraction of the amplitude of the lmn overtone relative to the
fundamental mode, as many as the number of subdominant modes.
philmn : float
Phase of the lmn overtone, as many as the number of modes. Should also
include the information from the azimuthal angle (phi + m*Phi).
inclination : {None, float}, optional
Inclination of the system in radians. If None, the spherical harmonics
will be set to 1.
delta_t : {None, float}, optional
The time step used to generate the ringdown.
If None, it will be set to the inverse of the frequency at which the
amplitude is 1/1000 of the peak amplitude (the minimum of all modes).
t_final : {None, float}, optional
The ending time of the output frequency series.
If None, it will be set to the time at which the amplitude
is 1/1000 of the peak amplitude (the maximum of all modes).
Returns
-------
hplustilde: FrequencySeries
The plus phase of a ringdown with the lm modes specified and
n overtones in frequency domain.
hcrosstilde: FrequencySeries
The cross phase of a ringdown with the lm modes specified and
n overtones in frequency domain.
"""
input_params = props(template, freqtau_required_args, **kwargs)
# Get required args
f_0, tau = lm_freqs_taus(**input_params)
lmns = input_params['lmns']
for lmn in lmns:
if int(lmn[2]) == 0:
raise ValueError('Number of overtones (nmodes) must be greater '
'than zero.')
# following may not be in input_params
inc = input_params.pop('inclination', None)
delta_t = input_params.pop('delta_t', None)
t_final = input_params.pop('t_final', None)
if not delta_t:
delta_t = lm_deltat(f_0, tau, lmns)
if not t_final:
t_final = lm_tfinal(tau, lmns)
kmax = int(t_final / delta_t) + 1
# Different overtones will have different tapering window-size
# Find maximum window size to create long enough output vector
if taper:
taper_window = int(taper*max(tau.values())/delta_t)
kmax += taper_window
outplus = TimeSeries(zeros(kmax, dtype=float64), delta_t=delta_t)
outcross = TimeSeries(zeros(kmax, dtype=float64), delta_t=delta_t)
if taper:
start = - taper * max(tau.values())
outplus._epoch, outcross._epoch = start, start
for lmn in lmns:
l, m, nmodes = int(lmn[0]), int(lmn[1]), int(lmn[2])
hplus, hcross = get_td_lm(freqs=f_0, taus=tau, l=l, m=m, nmodes=nmodes,
taper=taper, inclination=inc, delta_t=delta_t,
t_final=t_final, **input_params)
if not taper:
outplus.data += hplus.data
outcross.data += hcross.data
else:
outplus = taper_shift(hplus, outplus)
outcross = taper_shift(hcross, outcross)
return outplus, outcross
def project_wave(self, hp, hc, ra, dec, polarization,
method='lal',
reference_time=None):
"""Return the strain of a waveform as measured by the detector.
Apply the time shift for the given detector relative to the assumed
geocentric frame and apply the antenna patterns to the plus and cross
polarizations.
Parameters
----------
hp: pycbc.types.TimeSeries
Plus polarization of the GW
hc: pycbc.types.TimeSeries
Cross polarization of the GW
ra: float
Right ascension of source location
dec: float
Declination of source location
polarization: float
Polarization angle of the source
method: {'lal', 'constant', 'vary_polarization'}
The method to use for projecting the polarizations into the
detector frame. Default is 'lal'.
reference_time: float, Optional
The time to use as, a reference for some methods of projection.
Used by 'constant' and 'vary_polarization' methods. Uses average
time if not provided.
"""
# The robust and most fefature rich method which includes
# time changing antenna patterns and doppler shifts due to the
# earth rotation and orbit
if method == 'lal':
import lalsimulation
h_lal = lalsimulation.SimDetectorStrainREAL8TimeSeries(
hp.astype(np.float64).lal(), hc.astype(np.float64).lal(),
ra, dec, polarization, self.lal())
ts = TimeSeries(
h_lal.data.data, delta_t=h_lal.deltaT, epoch=h_lal.epoch,
dtype=np.float64, copy=False)
# 'constant' assume fixed orientation relative to source over the
# duration of the signal, accurate for short duration signals
# 'fixed_polarization' applies only time changing orientation
# but no doppler corrections
elif method in ['constant', 'vary_polarization']:
if reference_time is not None:
rtime = reference_time
else:
# In many cases, one should set the reference time if using
# this method as we don't know where the signal is within
# the given time series. If not provided, we'll choose
# the midpoint time.
rtime = (float(hp.end_time) + float(hp.start_time)) / 2.0
if method == 'constant':
time = rtime
elif method == 'vary_polarization':
if (not isinstance(hp, TimeSeries) or
not isinstance(hc, TimeSeries)):
raise TypeError('Waveform polarizations must be given'
' as time series for this method')
# this is more granular than needed, may be optimized later
# assume earth rotation in ~30 ms needed for earth ceneter
# to detector is completely negligible.
time = hp.sample_times.numpy()
fp, fc = self.antenna_pattern(ra, dec, polarization, time)
dt = self.time_delay_from_earth_center(ra, dec, rtime)
ts = fp * hp + fc * hc
ts.start_time = float(ts.start_time) + dt
# add in only the correction for the time variance in the polarization
# due to the earth's rotation, no doppler correction applied
else:
raise ValueError("Unkown projection method {}".format(method))
return ts
def get_td_lm(template=None, taper=None, **kwargs):
"""Return frequency domain lm mode with the given number of overtones.
Parameters
----------
template: object
An object that has attached properties. This can be used to substitute
for keyword arguments. A common example would be a row in an xml table.
taper: {None, float}, optional
Tapering at the beginning of the waveform with duration taper * tau.
This option is recommended with timescales taper=1./2 or 1. for
time-domain ringdown-only injections.
The abrupt turn on of the ringdown can cause issues on the waveform
when doing the fourier transform to the frequency domain. Setting
taper will add a rapid ringup with timescale tau/10.
Each overtone will have a different taper depending on its tau, the
final taper being the superposition of all the tapers.
final_mass : float
Mass of the final black hole.
final_spin : float
Spin of the final black hole.
l : int
l mode (lm modes available: 22, 21, 33, 44, 55).
m : int
m mode (lm modes available: 22, 21, 33, 44, 55).
nmodes: int
Number of overtones desired (maximum n=8)
amp220 : float
Amplitude of the fundamental 220 mode, needed for any lm.
amplmn : float
Fraction of the amplitude of the lmn overtone relative to the
fundamental mode, as many as the number of subdominant modes.
philmn : float
Phase of the lmn overtone, as many as the number of nmodes.
delta_t : {None, float}, optional
The time step used to generate the ringdown.
If None, it will be set to the inverse of the frequency at which the
amplitude is 1/1000 of the peak amplitude (the minimum of all modes).
t_final : {None, float}, optional
The ending time of the output time series.
If None, it will be set to the time at which the amplitude is
1/1000 of the peak amplitude (the maximum of all modes).
Returns
-------
hplustilde: FrequencySeries
The plus phase of a lm mode with overtones (n) in frequency domain.
hcrosstilde: FrequencySeries
The cross phase of a lm mode with overtones (n) in frequency domain.
"""
input_params = props(template, lm_required_args, **kwargs)
# Get required args
amps, phis = lm_amps_phases(**input_params)
final_mass = input_params.pop('final_mass')
final_spin = input_params.pop('final_spin')
l, m = input_params.pop('l'), input_params.pop('m')
nmodes = input_params.pop('nmodes')
if int(nmodes) == 0:
raise ValueError('Number of overtones (nmodes) must be greater '
'than zero.')
# The following may not be in input_params
delta_t = input_params.pop('delta_t', None)
t_final = input_params.pop('t_final', None)
if delta_t is None:
delta_t = lm_deltat(final_mass, final_spin,
['%d%d%d' % (l, m, nmodes)])
if t_final is None:
t_final = lm_tfinal(final_mass, final_spin,
['%d%d%d' % (l, m, nmodes)])
f_0, tau = get_lm_f0tau(final_mass, final_spin, l, m, nmodes)
kmax = int(t_final / delta_t) + 1
# Different overtones will have different tapering window-size
# Find maximum window size to create long enough output vector
if taper is not None:
taper_window = int(taper * max(tau) / delta_t)
kmax += taper_window
outplus = TimeSeries(zeros(kmax, dtype=float64), delta_t=delta_t)
outcross = TimeSeries(zeros(kmax, dtype=float64), delta_t=delta_t)
for n in range(nmodes):
hplus, hcross = get_td_qnm(template=None,
taper=taper,
f_0=f_0[n],
tau=tau[n],
phi=phis['%d%d%d' % (l, m, n)],
amp=amps['%d%d%d' % (l, m, n)],
delta_t=delta_t,
t_final=t_final)
if taper is None:
outplus.data += hplus.data
outcross.data += hcross.data
else:
outplus = taper_shift(hplus, outplus)
outcross = taper_shift(hcross, outcross)
return outplus, outcross
def rescale_wave(self, M=None, inclination=None, phi=None, distance=None):
""" Rescale modes and polarizations to given mass, angles, distance.
Note that this function re-sets the stored values of binary parameters
and so all future calculations will assume new values unless otherwise
specified.
"""
#{{{
#
# If MASS has changed, rescale modes
#
if self.totalmass != M and M is not None:
# Rescale the time-axis for all modes
self.rescaledmodes_real, self.rescaledmodes_imag = {}, {}
for modeL in np.arange( 2, self.modeLmax+1 ):
self.rescaledmodes_real[modeL], self.rescaledmodes_imag[modeL] = {}, {}
for modeM in np.arange( -1*modeL, modeL+1 ):
if self.skipM0 and modeM==0: continue
self.rescaledmodes_real[modeL][modeM], \
self.rescaledmodes_imag[modeL][modeM] = \
self.rescale_mode(M, modeL=modeL, modeM=modeM)
self.totalmass = M
elif self.totalmass == None and M == None:
raise IOError("Please provide a total-mass value to rescale")
#
# Now rescale with distance and ANGLES
#
if inclination is not None: self.inclination = inclination
if phi is not None: self.phi = phi
if distance is not None: self.distance = distance
# Mass / distance scaling pre-factor
scalefac = self.totalmass * lal.MRSUN_SI / self.distance / lal.PC_SI
# Orbital phase at the time of merger (time of amplitude peak)
amp22 = self.get_mode_amplitude(totalmass=self.totalmass,
modeL=2, modeM=2, dimensionless=False)
iPeak, aPeak = self.get_peak_amplitude(amp=amp22)
#phase22 = self.get_mode_phase(totalmass=self.totalmass, dimensionless=False)
#phiOrbMerger = phase22[iPeak] / 2.
# Combine all modes
hp, hc = np.zeros(self.n, dtype=float), np.zeros(self.n, dtype=float)
for modeL in np.arange( 2, self.modeLmax+1 ):
for modeM in np.arange( -1*modeL, modeL+1 ):
if self.skipM0 and modeM==0: continue
# h+ - \ii hx = \Sum Ylm * hlm
ArcTan2Merger = np.arctan2(self.rescaledmodes_imag[modeL][modeM].data[iPeak],\
self.rescaledmodes_real[modeL][modeM].data[iPeak])
if self.verbose:
print "arctan2 at merger after: ", ArcTan2Merger
#curr_ylm = np.exp(1 * modeM * phiOrbMerger * 1j)
curr_ylm = np.exp(-1 * ArcTan2Merger * 1j)
if self.debug and curr_ylm: print curr_ylm / np.abs(curr_ylm)
curr_ylm *= lal.SpinWeightedSphericalHarmonic(\
self.inclination, self.phi, -2, modeL, modeM)
if self.debug and curr_ylm: print curr_ylm / np.abs(curr_ylm)
#
if self.debug:
print ( np.arctan2(curr_ylm.imag, curr_ylm.real) + (modeM*phiOrbMerger) ) / np.pi,\
( np.arctan2(curr_ylm.imag, curr_ylm.real) + (ArcTan2Merger) ) / np.pi
print ( np.arctan2(curr_ylm.imag, curr_ylm.real) - (modeM*phiOrbMerger) ) / np.pi,\
( np.arctan2(curr_ylm.imag, curr_ylm.real) - (ArcTan2Merger) ) / np.pi
##
hp += self.rescaledmodes_real[modeL][modeM].data * curr_ylm.real - \
self.rescaledmodes_imag[modeL][modeM].data * curr_ylm.imag
hc -= self.rescaledmodes_real[modeL][modeM].data * curr_ylm.imag + \
self.rescaledmodes_imag[modeL][modeM].data * curr_ylm.real
if self.debug: print "END\n\n"
# Scale amplitude by mass and distance factors
self.rescaled_hp = TimeSeries(scalefac * hp, delta_t=self.dt, epoch=0)
self.rescaled_hc = TimeSeries(scalefac * hc, delta_t=self.dt, epoch=0)
return [self.rescaled_hp, self.rescaled_hc]
def apply(self, strain, detector_name, f_lower=None, distance_scale=1):
"""Add injections (as seen by a particular detector) to a time series.
Parameters
----------
strain : TimeSeries
Time series to inject signals into, of type float32 or float64.
detector_name : string
Name of the detector used for projecting injections.
f_lower : {None, float}, optional
Low-frequency cutoff for injected signals. If None, use value
provided by each injection.
distance_scale: {1, foat}, optional
Factor to scale the distance of an injection with. The default is
no scaling.
Returns
-------
None
Raises
------
TypeError
For invalid types of `strain`.
"""
if strain.dtype not in (float32, float64):
raise TypeError("Strain dtype must be float32 or float64, not " \
+ str(strain.dtype))
lalstrain = strain.lal()
detector = Detector(detector_name)
earth_travel_time = lal.REARTH_SI / lal.C_SI
t0 = float(strain.start_time) - earth_travel_time
t1 = float(strain.end_time) + earth_travel_time
# pick lalsimulation injection function
add_injection = injection_func_map[strain.dtype]
for inj in self.table:
# roughly estimate if the injection may overlap with the segment
end_time = inj.get_time_geocent()
#CHECK: This is a hack (10.0s); replace with an accurate estimate
inj_length = 10.0
eccentricity = 0.0
polarization = 0.0
start_time = end_time - 2 * inj_length
if end_time < t0 or start_time > t1:
continue
# compute the waveform time series
hp, hc = sim.SimBurstSineGaussian(float(inj.q),
float(inj.frequency),
float(inj.hrss),
float(eccentricity),
float(polarization),
float(strain.delta_t))
hp = TimeSeries(hp.data.data[:], delta_t=hp.deltaT, epoch=hp.epoch)
hc = TimeSeries(hc.data.data[:], delta_t=hc.deltaT, epoch=hc.epoch)
hp._epoch += float(end_time)
hc._epoch += float(end_time)
if float(hp.start_time) > t1:
continue
# compute the detector response, taper it if requested
# and add it to the strain
strain = wfutils.taper_timeseries(strain, inj.taper)
signal_lal = hp.astype(strain.dtype).lal()
add_injection(lalstrain, signal_lal, None)
strain.data[:] = lalstrain.data.data[:]
def convert_lalREAL8TimeSeries_to_TimeSeries( h ):
return TimeSeries(h.data.data, delta_t=h.deltaT, \
copy=True, epoch=h.epoch, dtype=h.data.data.dtype)
class DataBuffer(object):
"""A linear buffer that acts as a FILO for reading in frame data
"""
def __init__(self, frame_src,
channel_name,
start_time,
max_buffer=2048,
force_update_cache=True,
increment_update_cache=None):
""" Create a rolling buffer of frame data
Parameters
---------
frame_src: str of list of strings
Strings that indicate where to read from files from. This can be a
list of frame files, a glob, etc.
channel_name: str
Name of the channel to read from the frame files
start_time:
Time to start reading from.
max_buffer: {int, 2048}, Optional
Length of the buffer in seconds
"""
self.frame_src = frame_src
self.channel_name = channel_name
self.read_pos = start_time
self.force_update_cache = force_update_cache
self.increment_update_cache = increment_update_cache
self.update_cache()
self.channel_type, self.raw_sample_rate = self._retrieve_metadata(self.stream, self.channel_name)
raw_size = self.raw_sample_rate * max_buffer
self.raw_buffer = TimeSeries(zeros(raw_size, dtype=numpy.float64),
copy=False,
epoch=start_time - max_buffer,
delta_t=1.0/self.raw_sample_rate)
def update_cache(self):
"""Reset the lal cache. This can be used to update the cache if the
result may change due to more files being added to the filesystem,
for example.
"""
cache = locations_to_cache(self.frame_src)
stream = lalframe.FrStreamCacheOpen(cache)
self.stream = stream
def _retrieve_metadata(self, stream, channel_name):
"""Retrieve basic metadata by reading the first file in the cache
Parameters
----------
stream: lal stream object
Stream containing a channel we want to learn about
channel_name: str
The name of the channel we want to know the dtype and sample rate of
Returns
-------
channel_type: lal type enum
Enum value which indicates the dtype of the channel
sample_rate: int
The sample rate of the data within this channel
"""
data_length = lalframe.FrStreamGetVectorLength(channel_name, stream)
channel_type = lalframe.FrStreamGetTimeSeriesType(channel_name, stream)
create_series_func = _fr_type_map[channel_type][2]
get_series_metadata_func = _fr_type_map[channel_type][3]
series = create_series_func(channel_name, stream.epoch, 0, 0,
lal.ADCCountUnit, 0)
get_series_metadata_func(series, stream)
return channel_type, int(1.0/series.deltaT)
def _read_frame(self, blocksize):
"""Try to read the block of data blocksize seconds long
Parameters
----------
blocksize: int
The number of seconds to attempt to read from the channel
Returns
-------
data: TimeSeries
TimeSeries containg 'blocksize' seconds of frame data
Raises
------
RuntimeError:
If data cannot be read for any reason
"""
try:
read_func = _fr_type_map[self.channel_type][0]
dtype = _fr_type_map[self.channel_type][1]
data = read_func(self.stream, self.channel_name,
self.read_pos, int(blocksize), 0)
return TimeSeries(data.data.data, delta_t=data.deltaT,
epoch=self.read_pos,
dtype=dtype)
except Exception as e:
raise RuntimeError('Cannot read requested frame data')
def null_advance(self, blocksize):
"""Advance and insert zeros
Parameters
----------
blocksize: int
The number of seconds to attempt to read from the channel
"""
self.raw_buffer.roll(-int(blocksize * self.raw_sample_rate))
self.read_pos += blocksize
self.raw_buffer.start_time += blocksize
def advance(self, blocksize):
"""Add blocksize seconds more to the buffer, push blocksize seconds
from the beginning.
Parameters
----------
blocksize: int
The number of seconds to attempt to read from the channel
"""
ts = self._read_frame(blocksize)
self.raw_buffer.roll(-len(ts))
self.raw_buffer[-len(ts):] = ts[:]
self.read_pos += blocksize
self.raw_buffer.start_time += blocksize
return ts
def update_cache_by_increment(self, blocksize):
"""Update the internal cache by starting from the first frame
and incrementing.
Guess the next frame file name by incrementing from the first found
one. This allows a pattern to be used for the GPS folder of the file,
which is indicated by `GPSX` where x is the number of digits to use.
Parameters
----------
blocksize: int
Number of seconds to increment the next frame file.
"""
start = float(self.raw_buffer.end_time)
end = float(start + blocksize)
if not hasattr(self, 'dur'):
fname = glob.glob(self.frame_src[0])[0]
fname = os.path.splitext(os.path.basename(fname))[0].split('-')
self.beg = '-'.join([fname[0], fname[1]])
self.ref = int(fname[2])
self.dur = int(fname[3])
fstart = int(self.ref + numpy.floor((start - self.ref) / float(self.dur)) * self.dur)
starts = numpy.arange(fstart, end, self.dur).astype(numpy.int)
keys = []
for s in starts:
pattern = self.increment_update_cache
if 'GPS' in pattern:
n = int(pattern[int(pattern.index('GPS') + 3)])
pattern = pattern.replace('GPS%s' % n, str(s)[0:n])
name = '%s/%s-%s-%s.gwf' % (pattern, self.beg, s, self.dur)
# check that file actually exists, else abort now
if not os.path.exists(name):
logging.info("%s does not seem to exist yet" % name)
raise RuntimeError
keys.append(name)
cache = locations_to_cache(keys)
stream = lalframe.FrStreamCacheOpen(cache)
self.stream = stream
self.channel_type, self.raw_sample_rate = self._retrieve_metadata(self.stream, self.channel_name)
def attempt_advance(self, blocksize, timeout=10):
""" Attempt to advance the frame buffer. Retry upon failure, except
if the frame file is beyond the timeout limit.
Parameters
----------
blocksize: int
The number of seconds to attempt to read from the channel
timeout: {int, 10}, Optional
Number of seconds before giving up on reading a frame
Returns
-------
data: TimeSeries
TimeSeries containg 'blocksize' seconds of frame data
"""
if self.force_update_cache:
self.update_cache()
try:
if self.increment_update_cache:
self.update_cache_by_increment(blocksize)
return DataBuffer.advance(self, blocksize)
except RuntimeError:
if lal.GPSTimeNow() > timeout + self.raw_buffer.end_time:
# The frame is not there and it should be by now, so we give up
# and treat it as zeros
logging.info('Frame missing, giving up...')
DataBuffer.null_advance(self, blocksize)
return None
else:
# I am too early to give up on this frame, so we should try again
logging.info('Frame missing, waiting a bit more...')
time.sleep(1)
return self.attempt_advance(blocksize, timeout=timeout)
def taper_filter_waveform( self, hpsamp=None, hcsamp=None, tapermethod='planck', \
ttaper1=100, ttaper2=1000, ftaper3=0.1, ttaper4=100., \
npad=00, f_filter=-1., \
verbose=False):
"""Tapers using a Plank-taper window and high-pass filters.
**IMPORTANT** The domain of the window is passed as ttaper{1,2,3,4} values.
ttaper1 : time (in total-mass units) from the start where the window starts
ttaper2 : width of start window
ftaper3 : fraction by which amplitude should fall after its peak,
marking where the rolldown window starts
ttaper4 : width of the rolldown window
Currently supported tapermethods: 'planck' [default], 'cosine'
"""
#{{{
if hpsamp and hcsamp: hp0, hc0 = [hpsamp, hcsamp]
elif self.rescaled_hp is not None and self.rescaled_hc is not None:
totalmass = self.totalmass
hp0, hc0 = [self.rescaled_hp, self.rescaled_hc]
else: raise IOError("Please provide either the total mass (and strain)")
# Check windowing extents
if ttaper1 > ttaper2 or \
(ttaper1+ttaper2+ttaper4) > (len(hp0)*hp0.delta_t/self.totalmass/lal.MTSUN_SI):
raise IOError("Invalid window configuration with [%f,%f,%f,%f]" %\
(ttaper1, ttaper2, ftaper3, ttaper4))
#
hp = TimeSeries( hp0.data, dtype=hp0.dtype, delta_t=hp0.delta_t, epoch=hp0._epoch )
hc = TimeSeries( hc0.data, dtype=hc0.dtype, delta_t=hc0.delta_t, epoch=hc0._epoch )
# Get actual waveform length
for idx in np.arange( len(hp)-1, 0, -1 ):
if hp[idx]==0 and hc[idx]==0: break
N = idx #np.where( hp.data == 0 )[0][0]
# Check npad
if abs(len(hp) - N) < npad:
print >>sys.stdout, "Ignoring npad..\n"
npad = 0
else:
# Prepend some zeros to the waveform (assuming there are ''npad'' zeros at the end)
hp = zero_pad_beginning( hp, steps=npad )
hc = zero_pad_beginning( hc, steps=npad )
#
# ########## Construct the taper window #############
#
# Get the amplitude peak
amp = amplitude_from_polarizations(hp, hc)
max_a, nPeak = amp.abs_max_loc()
# First get the starting-half indices
ttapers = np.array([ttaper1, ttaper2], dtype=np.float128)
ntapers = np.int64(\
np.round(ttapers * self.totalmass * lal.MTSUN_SI * self.sample_rate))
ntaper1, ntaper2 = ntapers
ntaper2 += ntaper1
if ntaper2 < ntaper1:
raise RuntimeError("Could not configure starting taper-window")
# Next get the next-half indices
amp_after_peak = amp[nPeak:]
iA, vA = min(enumerate(amp_after_peak),key=lambda x:abs(x[1] - ftaper3*max_a))
ntaper3 = nPeak + iA
#iB, vB = min(enumerate(amp_after_peak),key=lambda x:abs(x[1] - 0.01*max_a))
#iB = iA + ntaper4
ntaper4 = np.int64(\
np.round(ttaper4 * self.totalmass * lal.MTSUN_SI * self.sample_rate))
ntaper4 += ntaper3
if ntaper3 <= nPeak or ntaper4 < ntaper3:
tmp_data = amp_after_peak.data
for idx in range( len(amp_after_peak) ):
if tmp_data[idx] < ftaper3*max_a: break
ntaper3 = nPeak + idx
for idx in range( len(amp_after_peak) ):
if tmp_data[idx] < ftaper4*max_a: break
ntaper4 = nPeak + idx
if ntaper3 <= nPeak or ntaper4 < ntaper3:
raise RuntimeError("Could not configure ringdown tapering window")
ntapers = np.array([ntaper1, ntaper2, ntaper3, ntaper4], dtype=np.int64)
ttapers = np.float128(ntapers) / self.sample_rate
time_array = hp.sample_times.data - np.float(hp._epoch)
#
# Actual windowing function
#
region1 = np.zeros(ntaper1)
region2 = np.zeros(ntaper2 - ntaper1)
region3 = np.ones(ntaper3 - ntaper2)
region4 = np.zeros(ntaper4 - ntaper3)
region5 = np.zeros(len(hp) - ntaper4)
#
if 'planck' in tapermethod:
np.seterr(divide='raise',over='raise',under='ignore',invalid='raise')
t1, t2, t3, t4 = ttapers
i1, i2, i3, i4 = ntapers
if verbose:
print "window times = ", t1, t2, t3, t4, " idxs = ", i1, i2, i3, i4
#
for i in range(len(region2)):
if i == 0:
region2[i] = 0
continue
try:
region2[i] = 1./(np.exp( ((t2-t1)/(time_array[i+i1]-t1)) + \
((t2-t1)/(time_array[i+i1]-t2)) ) + 1)
except:
if time_array[i+i1]>0.9*t1 and time_array[i+i1]<1.1*t1: region2[i] = 0
if time_array[i+i1]>0.9*t2 and time_array[i+i1]<1.1*t2: region2[i] = 1.
#
for i in range(len(region4)):
if i == 0:
region4[i] = 1.
continue
try:
region4[i] = 1./(np.exp( ((t3-t4)/(time_array[i+i3]-t3)) + \
((t3-t4)/(time_array[i+i3]-t4)) ) + 1)
except:
if time_array[i+i3]>0.9*t3 and time_array[i+i3]<1.1*t3: region4[i] = 1.
if time_array[i+i3]>0.9*t4 and time_array[i+i3]<1.1*t4: region4[i] = 0
#
if verbose and False:
import matplotlib.pyplot as plt
plt.plot(np.arange(len(region1))*hp.delta_t, region1)
offset = len(region1)
plt.plot((offset+np.arange(len(region2)))*hp.delta_t, region2)
offset += len(region2)
plt.plot((offset+np.arange(len(region3)))*hp.delta_t, region3)
offset += len(region3)
plt.plot((offset+np.arange(len(region4)))*hp.delta_t, region4)
plt.grid()
plt.show()
win = np.concatenate((region1,region2,region3,region4,region5))
elif 'cos' in tapermethod:
win = region1
win12 = 0.5 + 0.5*np.array([np.cos( np.pi*(float(j-ntaper1)/float(ntaper2-\
ntaper1) - 1)) for j in np.arange(ntaper1,ntaper2)])
win = np.append(win, win12)
win = np.append(win, region3)
win34 = 0.5 - 0.5*np.array([np.cos( np.pi*(float(j-ntaper3)/float(ntaper4-\
ntaper3) - 1)) for j in np.arange(ntaper3,ntaper4)])
win = np.append(win, win34)
win = np.append(win, region5)
else: raise IOError("Please specify valid taper-method")
#
# ########### Taper & Filter the waveform ##############
#
hp.data *= win
hc.data *= win
#
# High pass filter the waveform
if f_filter > 0:
hplal = convert_TimeSeries_to_lalREAL8TimeSeries( hp )
hclal = convert_TimeSeries_to_lalREAL8TimeSeries( hc )
lal.HighPassREAL8TimeSeries( hplal, f_filter, 0.9, 8 )
lal.HighPassREAL8TimeSeries( hclal, f_filter, 0.9, 8 )
hp = convert_lalREAL8TimeSeries_to_TimeSeries( hplal )
hc = convert_lalREAL8TimeSeries_to_TimeSeries( hclal )
return hp, hc
def inverse_spectrum_truncation(psd, max_filter_len, low_frequency_cutoff=None, trunc_method=None):
"""Modify a PSD such that the impulse response associated with its inverse
square root is no longer than `max_filter_len` time samples. In practice
this corresponds to a coarse graining or smoothing of the PSD.
Parameters
----------
psd : FrequencySeries
PSD whose inverse spectrum is to be truncated.
max_filter_len : int
Maximum length of the time-domain filter in samples.
low_frequency_cutoff : {None, int}
Frequencies below `low_frequency_cutoff` are zeroed in the output.
trunc_method : {None, 'hann'}
Function used for truncating the time-domain filter.
None produces a hard truncation at `max_filter_len`.
Returns
-------
psd : FrequencySeries
PSD whose inverse spectrum has been truncated.
Raises
------
ValueError
For invalid types or values of `max_filter_len` and `low_frequency_cutoff`.
Notes
-----
See arXiv:gr-qc/0509116 for details.
"""
# sanity checks
if type(max_filter_len) is not int or max_filter_len <= 0:
raise ValueError('max_filter_len must be a positive integer')
if low_frequency_cutoff is not None and low_frequency_cutoff < 0 \
or low_frequency_cutoff > psd.sample_frequencies[-1]:
raise ValueError('low_frequency_cutoff must be within the bandwidth of the PSD')
N = (len(psd)-1)*2
inv_asd = FrequencySeries((1. / psd)**0.5, delta_f=psd.delta_f, \
dtype=complex_same_precision_as(psd))
inv_asd[0] = 0
inv_asd[N/2] = 0
q = TimeSeries(numpy.zeros(N), delta_t=(N / psd.delta_f), \
dtype=real_same_precision_as(psd))
if low_frequency_cutoff:
kmin = int(low_frequency_cutoff / psd.delta_f)
inv_asd[0:kmin] = 0
ifft(inv_asd, q)
trunc_start = max_filter_len / 2
trunc_end = N - max_filter_len / 2
if trunc_method == 'hann':
trunc_window = Array(numpy.hanning(max_filter_len), dtype=q.dtype)
q[0:trunc_start] *= trunc_window[max_filter_len/2:max_filter_len]
q[trunc_end:N] *= trunc_window[0:max_filter_len/2]
q[trunc_start:trunc_end] = 0
psd_trunc = FrequencySeries(numpy.zeros(len(psd)), delta_f=psd.delta_f, \
dtype=complex_same_precision_as(psd))
fft(q, psd_trunc)
psd_trunc *= psd_trunc.conj()
psd_out = 1. / abs(psd_trunc)
return psd_out
class DataBuffer(object):
""" A linear buffer that acts as a FILO for reading in frame data
"""
def __init__(self, frame_src,
channel_name,
start_time,
max_buffer=2048):
""" Create a rolling buffer of frame data
Parameters
---------
frame_src: str of list of strings
Strings that indicate where to read from files from. This can be a
list of frame files, a glob, etc.
channel_name: str
Name of the channel to read from the frame files
start_time:
Time to start reading from.
max_buffer: {int, 2048}, Optional
Length of the buffer in seconds
"""
self.frame_src = frame_src
self.channel_name = channel_name
self.read_pos = start_time
self.update_cache()
self.channel_type, self.sample_rate = self._retrieve_metadata(self.stream, self.channel_name)
raw_size = self.sample_rate * max_buffer
self.raw_buffer = TimeSeries(zeros(raw_size, dtype=numpy.float64),
copy=False,
epoch=start_time - max_buffer,
delta_t=1.0/self.sample_rate)
def update_cache(self):
""" Reset the lal cache. This can be used to update the cache if the
result may change due to more files being added to the filesystem,
for example.
"""
cache = locations_to_cache(self.frame_src)
stream = lalframe.FrStreamCacheOpen(cache)
self.stream = stream
def _retrieve_metadata(self, stream, channel_name):
""" Retrieve basic metadata by reading the first file in the cache
Parameters
----------
stream: lal stream object
Stream containing a channel we want to learn about
channel_name: str
The name of the channel we want to know the dtype and sample rate of
Returns
-------
channel_type: lal type enum
Enum value which indicates the dtype of the channel
sample_rate: int
The sample rate of the data within this channel
"""
data_length = lalframe.FrStreamGetVectorLength(channel_name, stream)
channel_type = lalframe.FrStreamGetTimeSeriesType(channel_name, stream)
create_series_func = _fr_type_map[channel_type][2]
get_series_metadata_func = _fr_type_map[channel_type][3]
series = create_series_func(channel_name, stream.epoch, 0, 0,
lal.ADCCountUnit, 0)
get_series_metadata_func(series, stream)
return channel_type, int(1.0/series.deltaT)
def _read_frame(self, blocksize):
""" Try to read the block of data blocksize seconds long
Parameters
----------
blocksize: int
The number of seconds to attempt to read from the channel
Returns
-------
data: TimeSeries
TimeSeries containg 'blocksize' seconds of frame data
Raises
------
RuntimeError:
If data cannot be read for any reason
"""
try:
read_func = _fr_type_map[self.channel_type][0]
dtype = _fr_type_map[self.channel_type][1]
data = read_func(self.stream, self.channel_name, self.read_pos, blocksize, 0)
return TimeSeries(data.data.data, delta_t=data.deltaT,
epoch=self.read_pos,
dtype=dtype)
except:
raise RuntimeError('Cannot read requested frame data')
def null_advance(self, blocksize):
""" Advance and insert zeros
Parameters
----------
blocksize: int
The number of seconds to attempt to read from the channel
"""
self.raw_buffer.roll(-int(blocksize * self.sample_rate))
self.raw_buffer.start_time += blocksize
def advance(self, blocksize):
""" Add blocksize seconds more to the buffer, push blocksize seconds
from the beginning.
Parameters
----------
blocksize: int
The number of seconds to attempt to read from the channel
"""
ts = self._read_frame(blocksize)
self.raw_buffer.roll(-len(ts))
self.raw_buffer[-len(ts):] = ts[:]
self.read_pos += blocksize
self.raw_buffer.start_time += blocksize
return ts
def attempt_advance(self, blocksize, timeout=10):
""" Attempt to advance the frame buffer. Retry upon failure, except
if the frame file is beyond the timeout limit.
Parameters
----------
blocksize: int
The number of seconds to attempt to read from the channel
timeout: {int, 10}, Optional
Number of seconds before giving up on reading a frame
Returns
-------
data: TimeSeries
TimeSeries containg 'blocksize' seconds of frame data
"""
self.update_cache()
try:
return DataBuffer.advance(self, blocksize)
except ValueError:
if lal.GPSTimeNow() > timeout + self.raw_buffer.end_time:
# The frame is not there and it should be by now, so we give up
# and treat it as zeros
self.null_advance(blocksize)
return None
else:
# I am too early to give up on this frame, so we should try again
return self.attempt_advance(self, blocksize, timeout=timeout)