matplotlib Code

#!/usr/bin/env python
"""Simple matshow() example."""

from matplotlib.pylab import *

def samplemat(dims):
    """Make a matrix with all zeros and increasing elements on the diagonal"""
    aa = zeros(dims)
    for i in range(min(dims)):
        aa[i,i] = i
    return aa

# Make a few matrices of strange sizes
dimlist = [(12,12),(128,64),(64,512),(1024,128)]

for d in dimlist:
    matshow(samplemat(d))

# Display a random matrix with a specified figure number and a grayscale colormap
matshow(rand(64,64),fignum=100,cmap=cm.gray)

show()