Plotting events as 2-d tiles¶

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

The data from which these events were generated are a simulation of Gaussian noise with the Advanced LIGO design spectrum, and so don’t actually contain any real gravitational waves, but will help tune the algorithm to improve detection of future, real signals.

First, we import the SnglBurstTable class

from gwpy.table.lsctables import SnglBurstTable

and read the table of events:

events = SnglBurstTable.read('../../gwpy/tests/data/H1-LDAS_STRAIN-968654552-10.xml.gz')

We can make a plot of these events as 2-dimensional tiles by specifying the x- and y-axis columns, and the widths in those directions:

plot = events.plot('time', 'central_freq', 'duration', 'bandwidth', color='snr', epoch=968654552)
plot.set_xlim(968654552, 968654552+10)
plot.set_ylabel('Frequency [Hz]')
plot.set_yscale('log')
plot.set_title('LIGO Hanford Observatory event triggers for GW100916')
plot.add_colorbar(clim=[1, 5], label='Signal-to-noise ratio', cmap='hot_r')
plot.show()

(Source code, png)