Colorplot that distinguishes between positive and negative values

Question

As one can see in this sample code since 0 is somewhere in the spectrum it is hard to trace which points are negative and which are positive. Although my real plot is more c

Answer 1

there is a lot of good example material on simple self-defined segmented color bars on the matplotlib documentation pages

for instance

http://matplotlib.org/examples/api/colorbar_only.html http://matplotlib.org/examples/pylab_examples/contourf_demo.html

EDIT:

from what I understand, this might be the perfect example for what you are looking for:

http://matplotlib.org/examples/pylab_examples/custom_cmap.html