Colorbar limits are not respecting set vmin/vmax in plt.contourf. How can I more explicitly set the colorbar limits?

Question

Getting a strange result when trying to adjust the data range when plotting using contourf

import matplotlib
import numpy as np
import matplotlib.cm as cm
im         


        

Answer 1

We can explicitly set the colorbar limits by sending a scalar mappable to colorbar.

CS = plt.contourf(X, Y, Z, 5, vmin = 0., vmax = 2., cmap=cm.coolwarm)
plt.title('Simplest default with labels')
m = plt.cm.ScalarMappable(cmap=cm.coolwarm)
m.set_array(Z)
m.set_clim(0., 2.)
plt.colorbar(m, boundaries=np.linspace(0, 2, 6))