title: How to replace colors of a colormap respresenting the two smallest values by white in matplolib?
body: <p>I am plotting an animated contourf map in matplotlib with a colorbar that changes at each frame. I want to keep the colorbar centered at zero (I am using a diverging colormap) and to do so I use an odd number of levels. The problem is, when I do this, even though the central color of the colormap (cm.seismic) is white, this color does not appear in the colormap. I want to be able to replace the color of the smallest values (the light red and the light blue) by white, so that instead of having one central level whose color is white (zero), I have two (two smallest values).</p>
  <p><a href="https://i.stack.imgur.com/2kc8X.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/2kc8X.png" alt="What I have / What I want" /></a></p>