color matplotlib patch with 2 colors or a gradient

Question

I need to coloring an Ellipse with two different colors. This could be done half and half or better, an horizontal gradient.

I would like to keep using matplotlib patches and not to use equations to draw the ellipse.

I'm using this minimal code to point the problem.

import matplotlib.pyplot as plt
import matplotlib.patches as mpatch

ax = plt.subplot(111)
ax.add_patch(mpatch.Ellipse(xy = [0.5, 0.5], width= 0.75, height=0.5, facecolor = 'blue'))
plt.show()

Anserws to How to draw a filled arc in matplotlib are directed to fill a circle arc except for one that can fill a ellipse arc.

This is a cartoon of what I need

http://stackoverflow.com/questions/10958835/matplotlib-color-gradient-in-patches — Chuck, Feb 09 '17 at 15:59
Both solutions proposed in that thread do not used matplotlib patches. — heracho, Feb 09 '17 at 16:28
I was thinking in to use wedge patch to draw half ellipses. but I don't know how to transform the semicircles in to 'semi-ellipses'. — heracho, Feb 09 '17 at 17:45
Possible duplicate of [How to draw a filled arc in matplotlib](http://stackoverflow.com/questions/30642391/how-to-draw-a-filled-arc-in-matplotlib) — ImportanceOfBeingErnest, Feb 09 '17 at 18:31

score -1 · Accepted Answer · edited May 23 '17 at 10:29

-1

The patch arc can draw a semi ellipse, but by default it can not be filled.

I found how to fill and arc in: How to draw a filled arc in matplotlib.

import matplotlib.pyplot as plt
import matplotlib.patches as mpatch

ax = plt.subplot(111)
ax.add_patch(mpatch.Arc(xy = [0.5, 0.5], width= 0.75, height=0.5, angle=.0, theta1= 90.0, theta2=-90.0, color = 'blue', hatch = 'OOOO'))
ax.add_patch(mpatch.Arc(xy = [0.5, 0.5], width= 0.75, height=0.5, angle=.0, theta1=-90.0, theta2= 90.0, color = 'green', hatch = 'OOOO'))

edited May 23 '17 at 10:29

Community

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answered Feb 09 '17 at 18:16

heracho

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This solution depends on image resolution, whit enough zoom it's possible to notice the points instead of a solid color. – heracho Feb 09 '17 at 23:57

color matplotlib patch with 2 colors or a gradient

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