.. _images_contours_and_fields-streamplot_demo_masking: images_contours_and_fields example code: streamplot_demo_masking.py =================================================================== .. plot:: /home/tcaswell/other_source/matplotlib/doc/mpl_examples/images_contours_and_fields/streamplot_demo_masking.py :: """ Demo of the streamplot function with masking. This example shows how streamlines created by the streamplot function skips masked regions and NaN values. """ import numpy as np import matplotlib.pyplot as plt w = 3 Y, X = np.mgrid[-w:w:100j, -w:w:100j] U = -1 - X**2 + Y V = 1 + X - Y**2 speed = np.sqrt(U*U + V*V) mask = np.zeros(U.shape, dtype=bool) mask[40:60, 40:60] = 1 U = np.ma.array(U, mask=mask) U[:20, :20] = np.nan plt.streamplot(X, Y, U, V, color='r') plt.imshow(~mask, extent=(-w, w, -w, w), alpha=0.5, interpolation='nearest', cmap=plt.cm.gray) plt.show() Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)