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

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

.. _sphx_glr_gallery_text_labels_and_annotations_engineering_formatter.py:


=========================================
Labeling ticks using engineering notation
=========================================

Use of the engineering Formatter.




.. image:: /gallery/text_labels_and_annotations/images/sphx_glr_engineering_formatter_001.png
    :class: sphx-glr-single-img





.. code-block:: python


    import matplotlib.pyplot as plt
    import numpy as np

    from matplotlib.ticker import EngFormatter

    # Fixing random state for reproducibility
    prng = np.random.RandomState(19680801)

    # Create artificial data to plot.
    # The x data span over several decades to demonstrate several SI prefixes.
    xs = np.logspace(1, 9, 100)
    ys = (0.8 + 0.4 * prng.uniform(size=100)) * np.log10(xs)**2

    # Figure width is doubled (2*6.4) to display nicely 2 subplots side by side.
    fig, (ax0, ax1) = plt.subplots(nrows=2, figsize=(7, 9.6))
    for ax in (ax0, ax1):
        ax.set_xscale('log')

    # Demo of the default settings, with a user-defined unit label.
    ax0.set_title('Full unit ticklabels, w/ default precision & space separator')
    formatter0 = EngFormatter(unit='Hz')
    ax0.xaxis.set_major_formatter(formatter0)
    ax0.plot(xs, ys)
    ax0.set_xlabel('Frequency')

    # Demo of the options `places` (number of digit after decimal point) and
    # `sep` (separator between the number and the prefix/unit).
    ax1.set_title('SI-prefix only ticklabels, 1-digit precision & '
                  'thin space separator')
    formatter1 = EngFormatter(places=1, sep="\N{THIN SPACE}")  # U+2009
    ax1.xaxis.set_major_formatter(formatter1)
    ax1.plot(xs, ys)
    ax1.set_xlabel('Frequency [Hz]')

    plt.tight_layout()
    plt.show()


.. _sphx_glr_download_gallery_text_labels_and_annotations_engineering_formatter.py:


.. only :: html

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



  .. container:: sphx-glr-download

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



  .. container:: sphx-glr-download

     :download:`Download Jupyter notebook: engineering_formatter.ipynb <engineering_formatter.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>`_
