Source code for ixpeobssim.evt.gti

# Copyright (C) 2022, the ixpeobssim team.
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# GNU General Public License for more details.
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# with this program; if not, write to the Free Software Foundation, Inc.,
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"""Data structures related to the good time intervals.

from __future__ import print_function, division

import numpy

from ixpeobssim.utils.logging_ import logger

# pylint: disable=invalid-name

[docs] class xGTIList(list): """Small convenience class representing a list of good time interval. The interfaces are fairly minimal, but since we use this in quite different places, it was handy to collect the useful stuff in one place. """ def __init__(self, start_met, stop_met, *gtis): """ """ list.__init__(self) self.start_met = start_met self.stop_met = stop_met self.span = self.stop_met - self.start_met for start, stop in gtis: self.append_gti(start, stop)
[docs] def append_gti(self, start, stop): """Append a new GTI to the list. """ assert start >= self.start_met assert stop <= self.stop_met self.append((start, stop))
[docs] def total_good_time(self): """Return the total good time. """ return sum(stop - start for start, stop in self)
[docs] def start_mets(self): """Return the value of the start MET values for the GTI. """ return [start for start, stop in self]
[docs] def stop_mets(self): """Return the value of the stop MET values for the GTI. """ return [stop for start, stop in self]
[docs] def all_mets(self): """Return all the MET values corresponding to the start or stop of the GTIs in the list. Note that Python supports the call to sum() with start set by keyword argument only since version 3.8, so we are refraining from that, here. """ return sum([[start, stop] for start, stop in self], [])
[docs] def complement(self): """Return the logical complement of the GTI list in the relevant time span, i.e., the list of time intervals between the start and the end of observation that are *not* good time intervals. These are the ones where we do not take celestial data and we can, e.g., take calibration data. See for the use of the iterator over the list. """ # This is an iterator to all the bounds of the GTIs except for the # start of the first GTI and the end of the last. iterator = iter(self.all_mets()[1:-1]) return [(start, next(iterator)) for start in iterator]
[docs] def filter_event_times(self, time_): """Filter a given array of event times and return a reduced array only containing the times within the good time intervals in the list, along with the corresponding boolean mask. The latter, in turn, can be used to filter ancillary related columns, e.g., the phase in simulations of periodic sources. """'Filtering %d event times according to the GTIs...', len(time_)) mask = numpy.zeros(time_.shape, dtype=bool) for (start, stop) in self: mask[numpy.logical_and(time_ >= start, time_ <= stop)] = True time_ = time_[mask]'Done, %d entries remaining.', len(time_)) return time_, mask
def __str__(self): """String formatting. """ text = 'List of good time intervals (%.3f s total over %.3f s span):' %\ (self.total_good_time(), self.span) for i, (start, stop) in enumerate(self): text = '%s\n[%3d] (%.3f--%.3f) or (%.3f--%.3f)' %\ (text, i + 1, start, stop, start - self.start_met, stop - self.start_met) return text
[docs] class xSimpleGTIList(xGTIList): """Subclass of xGTIList with a single GTI. """ def __init__(self, start_met, stop_met): """Constructor. """ xGTIList.__init__(self, start_met, stop_met, (start_met, stop_met))
[docs] class xUberGTIList(xGTIList): """Subclass of xGTIList with a single GTI including all the MET from -inf to inf. """ def __init__(self): """Constructor. """ start_met = -numpy.inf stop_met = numpy.inf xGTIList.__init__(self, start_met, stop_met, (start_met, stop_met))