

.. _sphx_glr_gallery_lines_bars_and_markers_cohere.py:


=====================================
Plotting the coherence of two signals
=====================================

An example showing how to plot the coherence of two signals.




.. image:: /gallery/lines_bars_and_markers/images/sphx_glr_cohere_001.png
    :align: center





.. code-block:: python

    import numpy as np
    import matplotlib.pyplot as plt

    # Fixing random state for reproducibility
    np.random.seed(19680801)

    dt = 0.01
    t = np.arange(0, 30, dt)
    nse1 = np.random.randn(len(t))                 # white noise 1
    nse2 = np.random.randn(len(t))                 # white noise 2

    # Two signals with a coherent part at 10Hz and a random part
    s1 = np.sin(2 * np.pi * 10 * t) + nse1
    s2 = np.sin(2 * np.pi * 10 * t) + nse2

    fig, axs = plt.subplots(2, 1)
    axs[0].plot(t, s1, t, s2)
    axs[0].set_xlim(0, 2)
    axs[0].set_xlabel('time')
    axs[0].set_ylabel('s1 and s2')
    axs[0].grid(True)

    cxy, f = axs[1].cohere(s1, s2, 256, 1. / dt)
    axs[1].set_ylabel('coherence')

    fig.tight_layout()
    plt.show()

**Total running time of the script:** ( 0 minutes  0.120 seconds)



.. container:: sphx-glr-footer


  .. container:: sphx-glr-download

     :download:`Download Python source code: cohere.py <cohere.py>`



  .. container:: sphx-glr-download

     :download:`Download Jupyter notebook: cohere.ipynb <cohere.ipynb>`

.. rst-class:: sphx-glr-signature

    `Generated by Sphinx-Gallery <https://sphinx-gallery.readthedocs.io>`_
