### Navigation

- index
- modules |
- home|
- examples|
- tutorials|
- pyplot|
- docs »

# Span Selector

The SpanSelector is a mouse widget to select a xmin/xmax range and plot the detail view of the selected region in the lower axes

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

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

    fig = plt.figure(figsize=(8, 6))
    ax = fig.add_subplot(211, facecolor='#FFFFCC')

    x = np.arange(0.0, 5.0, 0.01)
    y = np.sin(2*np.pi*x) + 0.5*np.random.randn(len(x))

    ax.plot(x, y, '-')
    ax.set_ylim(-2, 2)
    ax.set_title('Press left mouse button and drag to test')

    ax2 = fig.add_subplot(212, facecolor='#FFFFCC')
    line2, = ax2.plot(x, y, '-')

    def onselect(xmin, xmax):
        indmin, indmax = np.searchsorted(x, (xmin, xmax))
        indmax = min(len(x) - 1, indmax)

        thisx = x[indmin:indmax]
        thisy = y[indmin:indmax]
        line2.set_data(thisx, thisy)
        ax2.set_xlim(thisx[0], thisx[-1])
        ax2.set_ylim(thisy.min(), thisy.max())
        fig.canvas.draw()

    # set useblit True on gtkagg for enhanced performance
    span = SpanSelector(ax, onselect, 'horizontal', useblit=True,
                        rectprops=dict(alpha=0.5, facecolor='red'))

    plt.show()

Total running time of the script: ( 0 minutes 0.046 seconds)

Generated by Sphinx-Gallery