Creating a Colormap Legend in Matplotlib

Posted by Vince on Stack Overflow See other posts from Stack Overflow or by Vince
Published on 2010-03-15T23:47:26Z Indexed on 2010/03/15 23:49 UTC
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matplotlib

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python

Hi fellow Stackers!

I am using imshow() in matplotlib like so:

import numpy as np
import matplotlib.pyplot as plt
mat = '''SOME MATRIX'''
plt.imshow(mat, origin="lower", cmap='gray', interpolation='nearest')
plt.show()

How do I add a legend showing the numeric value for the different shades of gray. Sadly, my googling has not uncovered an answer :(

Thank you in advance for the help.

Vince

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