.. currentmodule:: gwpy.plot

.. _gwpy-plot-bode:

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Visualising filters (:class:`BodePlot`)
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Any time-domain or Fourier-domain filters can be visualised using the Bode plot, showing the magnitude (in decibels) and phase (in degrees) response of a linear time-invariant filter. The `BodePlot` allows for simple display of these responses for any filter, for example a 40-1000 Hertz band-pass filter:

.. plot::
   :include-source:

   from gwpy.signal.filter_design import bandpass
   from gwpy.plot import BodePlot
   zpk = bandpass(40, 1000, 4096, analog=True)
   plot = BodePlot(zpk, analog=True, title='40-1000\,Hz bandpass filter')
   plot.show()

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