def shift_waveform_phase_time(hp,
hc,
t_shift,
ph_shift,
trim_leading=False,
trim_trailing=True,
verbose=False):
"""
Input: hp, hc, where h = hp(t) + i hx(t) = Amp(t) * exp(-i * Phi(t))
Output: hp, hc, where h = Amp(t - t_c) * exp( -i * [Phi(t - t_c) + phi_c] )
"""
hpnew = TimeSeries(hp,
epoch=hp._epoch,
delta_t=hp.delta_t,
dtype=hp.dtype,
copy=True)
hcnew = TimeSeries(hc,
epoch=hc._epoch,
delta_t=hc.delta_t,
dtype=hc.dtype,
copy=True)
# First apply phase shift
if ph_shift != 0.:
amplitude = amplitude_from_polarizations(hpnew, hcnew)
phase = phase_from_polarizations(hpnew, hcnew)
if verbose:
print(("shifting by %f radians" % ph_shift))
phase = phase + ph_shift
hpnew = TimeSeries(amplitude * np.cos(phase + np.pi),
epoch=hpnew._epoch,
delta_t=hpnew.delta_t,
dtype=hpnew.dtype)
hcnew = TimeSeries(amplitude * np.sin(phase + np.pi),
epoch=hcnew._epoch,
delta_t=hcnew.delta_t,
dtype=hcnew.dtype)
# Now apply time shift
if t_shift != 0:
id_shift = int(np.round(np.abs(t_shift) / hpnew.delta_t))
if verbose:
print(("shifting by %d (%f)" % (id_shift, t_shift)))
if t_shift > 0:
hpnew.append_zeros(id_shift)
hcnew.append_zeros(id_shift)
else:
hpnew.prepend_zeros(id_shift)
hcnew.prepend_zeros(id_shift)
hpnew.roll(id_shift * np.sign(t_shift))
hcnew.roll(id_shift * np.sign(t_shift))
if trim_trailing:
hpnew = trim_trailing_zeros(hpnew)
hcnew = trim_trailing_zeros(hcnew)
if trim_leading:
hpnew = trim_leading_zeros(hpnew)
hcnew = trim_leading_zeros(hcnew)
# RETURN
return hpnew, hcnew
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)
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 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
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)
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)
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)
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)