.. sectionauthor:: Duncan Macleod <duncan.macleod@ligo.org>

.. currentmodule:: gwpy.spectrogram

Plotting a `Spectrogram`
########################

I would like to study the gravitational wave strain spectrogram around the time of an interesting simulated signal during the last science run (S6).



First, we import the :class:`~gwpy.timeseries.TimeSeries` and :meth:`~gwpy.timeseries.TimeSeries.get` the data:

.. code-block:: python

   from gwpy.timeseries import TimeSeries
   gwdata = TimeSeries.get(
       'H1:LDAS-STRAIN', 'September 16 2010 06:40', 'September 16 2010 06:50',
       verbose=True)


Next, we can calculate a `Spectrogram` using the 
:meth:`~gwpy.timeseries.TimeSeries.spectrogram` method of the #
`~gwpy.timeseries.TimeSeries` and a 5-second stride with a 2-second FFT and 
1-second overlap (50%):

.. code-block:: python

   specgram = gwdata.spectrogram(5, fftlength=2, overlap=1) ** (1/2.)


and can make a plot using the :meth:`~Spectrogram.plot` method

.. code-block:: python

   plot = specgram.plot(norm='log', vmin=1e-23, vmax=1e-19)
   plot.set_yscale('log')
   plot.set_ylim(40, 4000)
   plot.add_colorbar(
       label=r'Gravitational-wave amplitude [strain/$\sqrt{\mathrm{Hz}}$]')
   plot.show()

.. plot:: ../examples/spectrogram/plot.py