# Copyright (c) 2014-2017 Louisiana State University
#               2017-2025 Cardiff University
#
# This file is part of GWpy.
#
# GWpy 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.
#
# GWpy is distributed in the hope that it will be useful,
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
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# You should have received a copy of the GNU General Public License
# along with GWpy.  If not, see <http://www.gnu.org/licenses/>.

"""
.. sectionauthor:: Duncan Macleod <duncan.macleod@ligo.org>
.. currentmodule:: gwpy.table

Calculating (and plotting) rate versus time for an `EventTable`
###############################################################

I would like to study the rate at which event triggers are generated by the
`ExcessPower` gravitational-wave burst detection algorithm, over a small
stretch of data.

The data from which these events were generated contain a simulated
gravitational-wave signal, or hardware injection, used to validate
the performance of the LIGO detectors and downstream data analysis procedures.
"""

# %%
# First, we import the `EventTable` object and read in a set of events from
# a LIGO_LW-format XML file containing a
# :class:`sngl_burst <igwn_ligolw.lsctables.SnglBurstTable>` table
from gwpy.table import EventTable
events = EventTable.read(
    "H1-LDAS_STRAIN-968654552-10.xml.gz",
    tablename="sngl_burst",
    columns=["peak", "snr"],
)

# %%
# .. note::
#
#    Here we manually specify the `columns` to read in order to optimise
#    the `read()` operation to parse only the data we actually need.
#
# We can calculate the rate of events (in Hertz) using the
# :meth:`~EventTable.event_rate` method:

rate = events.event_rate(1, start=968654552, end=968654562)

# %%
# The :meth:`~EventTable.event_rate` method has returned a
# `~gwpy.timeseries.TimeSeries`, so we can display this using the
# :meth:`~gwpy.timeseries.TimeSeries.step` method of that object:

plot = rate.step()
ax = plot.gca()
ax.set_xlim(968654552, 968654562)
ax.set_ylabel("Event rate [Hz]")
ax.set_title("LIGO Hanford Observatory event rate for HW100916")
plot.show()