Plotting an EventTable in a scatter

We can use GWpy’s EventTable to download the catalogue of gravitational-wave detections, and create a scatter plot to investigate the mass distribution of events.

First, we can download the 'GWTC-1-confident' catalogue using EventTable.fetch_open_data():

from gwpy.table import EventTable
events = EventTable.fetch_open_data(
    "GWTC",
    columns=(
        "mass_1_source",
        "mass_2_source",
        "luminosity_distance",
        "network_matched_filter_snr",
    ),
)

We can now make a scatter plot by specifying the x- and y-axis columns, and (optionally) the colour:

plot = events.scatter(
    "mass_1_source", "mass_2_source",
    color="network_matched_filter_snr",
)
plot.colorbar(label="Signal-to-noise ratio (SNR)")
plot.show()

We can similarly plot how the total event mass is distributed with distance. First we have to build the total mass ('mtotal') column from the component masses:

events.add_column(
    events["mass_1_source"] + events["mass_2_source"],
    name="mtotal"
)

and now can make a new scatter plot:

plot = events.scatter("luminosity_distance", "mtotal")
plot.show()