Simple coherence spectrogram

This example shows the time-variation spectrogram of the estimated coherence between the differential-arm length servo control loop error signal for LIGO-Hanford (H1:LSC-DARM_IN1_DQ) and the motion of an optical periscope used to direct the main laser beam into the Hanford interferometer, around the time of GW170814.

gwpy-plot coherencegram \
    --chan H1:LSC-DARM_IN1_DQ H1:PEM-CS_ACC_PSL_PERISCOPE_X_DQ \
    --start 1186741560 \
    --duration 600 \
    --nds2-server nds.gwosc.org \
    --interactive

The same command can be executed directly in Python as:

from gwpy.cli.gwpy_plot import main
main([
    'coherencegram',
    '--chan', 'H1:LSC-DARM_IN1_DQ', 'H1:PEM-CS_ACC_PSL_PERISCOPE_X_DQ',
    '--start', '1186741560',
    '--duration', '600',
    '--nds2-server', 'nds.gwosc.org',
    '--interactive',
])

/home/duncan.macleod/gwpy-nightly-build/conda/envs/gwpy-nightly-3.11/lib/python3.11/site-packages/igwn_auth_utils/requests.py:46: DeprecationWarning: Support for identity-based X.509 credentials for LIGO.ORG is being dropped.
Calls to this utility will stop working on/around 20 May 2025.

For details on this change please see

https://computing.docs.ligo.org/guide/compsoft/roadmap/LVK/x509_retirement/

If you have questions about this message, or its implications, please
consider opening an IGWN Computing Help Desk ticket:

https://git.ligo.org/computing/helpdesk/-/issues/new
  return func(*args, **kwargs)
Program run time: 13.4