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

.. only:: html

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

        Click :ref:`here <sphx_glr_download_gallery_widgets_textbox.py>`
        to download the full example code

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

.. _sphx_glr_gallery_widgets_textbox.py:


=======
Textbox
=======

The Textbox widget lets users interactively provide text input, including
formulas. In this example, the plot is updated using the `.on_submit` method.
This method triggers the execution of the *submit* function when the
user presses enter in the textbox or leaves the textbox.

Note:  The `matplotlib.widgets.TextBox` widget is different from the following
static elements: :doc:`/tutorials/text/annotations` and
:doc:`/gallery/recipes/placing_text_boxes`.

.. GENERATED FROM PYTHON SOURCE LINES 15-49

.. code-block:: default


    import numpy as np
    import matplotlib.pyplot as plt
    from matplotlib.widgets import TextBox


    fig, ax = plt.subplots()
    fig.subplots_adjust(bottom=0.2)

    t = np.arange(-2.0, 2.0, 0.001)
    l, = ax.plot(t, np.zeros_like(t), lw=2)


    def submit(expression):
        """
        Update the plotted function to the new math *expression*.

        *expression* is a string using "t" as its independent variable, e.g.
        "t ** 3".
        """
        ydata = eval(expression)
        l.set_ydata(ydata)
        ax.relim()
        ax.autoscale_view()
        plt.draw()


    axbox = fig.add_axes([0.1, 0.05, 0.8, 0.075])
    text_box = TextBox(axbox, "Evaluate")
    text_box.on_submit(submit)
    text_box.set_val("t ** 2")  # Trigger `submit` with the initial string.

    plt.show()




.. image:: /gallery/widgets/images/sphx_glr_textbox_001.png
    :alt: textbox
    :class: sphx-glr-single-img





.. GENERATED FROM PYTHON SOURCE LINES 50-57

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

References
""""""""""

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

.. GENERATED FROM PYTHON SOURCE LINES 58-60

.. code-block:: default


    from matplotlib.widgets import TextBox








.. _sphx_glr_download_gallery_widgets_textbox.py:


.. only :: html

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



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

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



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

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