Re: [Matplotlib-users] Clipping Contours

On Tue, Oct 16, 2012 at 4:04 PM, T J <tj...@gm...> wrote:
> I'm interested in clipping the result of plt.contour (and
> plt.contourf) to a patch.  However, QuadContourSet does not have a
> set_clip_path() method.  Is there a way to do this?

QuadContourSet does not (I think it should), but LineCollection
instances in QuadContourSet.collections does. Below is a quick
example.

import matplotlib.pyplot as plt
import numpy as np

x = np.arange(100)-50
arr = (x**2 + x[:,np.newaxis]**2)**.5
cont = plt.contour(arr)
col1 = cont.collections[3] # contour line to clip with.
clip_path = col1.get_paths()[0] # Note that col1 may have multiple paths.
for col in cont.collections:
    col.set_clip_path(clip_path, col1.get_transform()) # set clip_path
for individual LineCollection instances.

plt.show()