.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "gallery/widgets/buttons.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

    .. meta::
        :keywords: codex

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

        :ref:`Go to the end <sphx_glr_download_gallery_widgets_buttons.py>`
        to download the full example code

.. rst-class:: sphx-glr-example-title

.. _sphx_glr_gallery_widgets_buttons.py:


=======
Buttons
=======

Constructing a simple button GUI to modify a sine wave.

The ``next`` and ``previous`` button widget helps visualize the wave with
new frequencies.

.. GENERATED FROM PYTHON SOURCE LINES 11-53

.. code-block:: Python


    import matplotlib.pyplot as plt
    import numpy as np

    from matplotlib.widgets import Button

    freqs = np.arange(2, 20, 3)

    fig, ax = plt.subplots()
    fig.subplots_adjust(bottom=0.2)
    t = np.arange(0.0, 1.0, 0.001)
    s = np.sin(2*np.pi*freqs[0]*t)
    l, = ax.plot(t, s, lw=2)


    class Index:
        ind = 0

        def next(self, event):
            self.ind += 1
            i = self.ind % len(freqs)
            ydata = np.sin(2*np.pi*freqs[i]*t)
            l.set_ydata(ydata)
            plt.draw()

        def prev(self, event):
            self.ind -= 1
            i = self.ind % len(freqs)
            ydata = np.sin(2*np.pi*freqs[i]*t)
            l.set_ydata(ydata)
            plt.draw()

    callback = Index()
    axprev = fig.add_axes([0.7, 0.05, 0.1, 0.075])
    axnext = fig.add_axes([0.81, 0.05, 0.1, 0.075])
    bnext = Button(axnext, 'Next')
    bnext.on_clicked(callback.next)
    bprev = Button(axprev, 'Previous')
    bprev.on_clicked(callback.prev)

    plt.show()




.. image-sg:: /gallery/widgets/images/sphx_glr_buttons_001.png
   :alt: buttons
   :srcset: /gallery/widgets/images/sphx_glr_buttons_001.png, /gallery/widgets/images/sphx_glr_buttons_001_2_00x.png 2.00x
   :class: sphx-glr-single-img





.. GENERATED FROM PYTHON SOURCE LINES 54-60

.. admonition:: References

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

   - `matplotlib.widgets.Button`


.. _sphx_glr_download_gallery_widgets_buttons.py:

.. only:: html

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

    .. container:: sphx-glr-download sphx-glr-download-jupyter

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

    .. container:: sphx-glr-download sphx-glr-download-python

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


.. only:: html

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

    `Gallery generated by Sphinx-Gallery <https://sphinx-gallery.github.io>`_