.. note::
    :class: sphx-glr-download-link-note

    Click :ref:`here <sphx_glr_download_gallery_images_contours_and_fields_image_zcoord.py>` to download the full example code
.. rst-class:: sphx-glr-example-title

.. _sphx_glr_gallery_images_contours_and_fields_image_zcoord.py:


==================================
Modifying the coordinate formatter
==================================

Modify the coordinate formatter to report the image "z"
value of the nearest pixel given x and y.
This functionality is built in by default, but it
is still useful to show how to customize the
`~.axes.Axes.format_coord` function.



.. code-block:: python

    import numpy as np
    import matplotlib.pyplot as plt

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


    X = 10*np.random.rand(5, 3)

    fig, ax = plt.subplots()
    ax.imshow(X, interpolation='nearest')

    numrows, numcols = X.shape


    def format_coord(x, y):
        col = int(x + 0.5)
        row = int(y + 0.5)
        if col >= 0 and col < numcols and row >= 0 and row < numrows:
            z = X[row, col]
            return 'x=%1.4f, y=%1.4f, z=%1.4f' % (x, y, z)
        else:
            return 'x=%1.4f, y=%1.4f' % (x, y)

    ax.format_coord = format_coord
    plt.show()




.. image:: /gallery/images_contours_and_fields/images/sphx_glr_image_zcoord_001.png
    :class: sphx-glr-single-img




------------

References
""""""""""

The use of the following functions, methods, classes and modules is shown
in this example:



.. code-block:: python


    import matplotlib
    matplotlib.axes.Axes.format_coord
    matplotlib.axes.Axes.imshow







.. _sphx_glr_download_gallery_images_contours_and_fields_image_zcoord.py:


.. only :: html

 .. container:: sphx-glr-footer
    :class: sphx-glr-footer-example



  .. container:: sphx-glr-download

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



  .. container:: sphx-glr-download

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


.. only:: html

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

    Keywords: matplotlib code example, codex, python plot, pyplot
    `Gallery generated by Sphinx-Gallery
    <https://sphinx-gallery.readthedocs.io>`_
