>>> """
=============
Check Buttons
=============

Turning visual elements on and off with check buttons.

This program shows the use of 'Check Buttons' which is similar to
check boxes. There are 3 different sine waves shown and we can choose which
waves are displayed with the check buttons.
"""
... import numpy as np
... import matplotlib.pyplot as plt
... from matplotlib.widgets import CheckButtons
... 
... t = np.arange(0.0, 2.0, 0.01)
... s0 = np.sin(2*np.pi*t)
... s1 = np.sin(4*np.pi*t)
... s2 = np.sin(6*np.pi*t)
... 
... fig, ax = plt.subplots()
... l0, = ax.plot(t, s0, visible=False, lw=2, color='k', label='2 Hz')
... l1, = ax.plot(t, s1, lw=2, color='r', label='4 Hz')
... l2, = ax.plot(t, s2, lw=2, color='g', label='6 Hz')
... plt.subplots_adjust(left=0.2)
... 
... lines = [l0, l1, l2]
... 
... # Make checkbuttons with all plotted lines with correct visibility
... rax = plt.axes([0.05, 0.4, 0.1, 0.15])
... labels = [str(line.get_label()) for line in lines]
... visibility = [line.get_visible() for line in lines]
... check = CheckButtons(rax, labels, visibility)
... 
... 
... def func(label):
...     index = labels.index(label)
...     lines[index].set_visible(not lines[index].get_visible())
...     plt.draw()
... 
... check.on_clicked(func)
... 
... plt.show()
... 
... #############################################################################
... #
... # .. admonition:: References
... #
... #    The use of the following functions, methods, classes and modules is shown
... #    in this example:
... #
... #    - `matplotlib.widgets.CheckButtons`
...