I have the following code:
matplotlib.pyplot.figure()
matplotlib.pyplot.imshow( myValues )
matplotlib.pyplot.colorbar()
matplotlib.pyplot.title( 'Values' )
matplotlib.pyplot.show()
which creates a pretty default colormap. myValues is in the range from [ -1.0, 1.0 ] (which perhaps changes later. I want to color all values that are 0.0 in white. How can I achieve this?
Regards, Maecky
This should do the job:
from matplotlib import pyplot as plt
import numpy as np
plt.figure()
myValues = np.random.random((10,10))*2 -1
plt.imshow( myValues ,cmap = "RdBu_r" , vmin=-1, vmax=1)
plt.colorbar()
plt.title( 'Values' )
plt.show()
Where the idea is to :
1- Choose a colormap that is white "in the middle", for instance RdBu_r. For more see:
2- Fix min and max value at equal distances from zero. In your case vmin=-1, vmax=1 is a obvious choice.
The problem of this solution is that in case you dataset's range is to be changed, values outside [vmin,vmax] will all be mapped to the same color. This may or may not be an issue depending of what you want to do.
