Python Matplotlib颜色条范围

Question

So, after searching for a few hours, I can't seem to find a simple answer to my issue. I have a filled contour plot (contourf) for whom I want the values displayed on the colorbar to be between -45 and 45.

fig, ax = plt.subplots()
plt.contourf(time_array, f, half_CP, 30, cmap=cm.seismic, vmin=-45, vmax=45)
cb = plt.colorbar()
plt.clim(-45,45)

clim has successfully compressed the range of colors displayed in my colorbar, however my colorbar is still displaying values from around -80 to 80... in other words, my vmin/vmax isn't working. I've tried putting this argument in the plt.colorbar line, however that has had no effect either.

I would not be surprised if it's something super-simple, but I've been trying to find the error/mistake/what I'm missing for a few hours now. I would appreciate any help!

Answer 1

I usually define a number of levels to contour, which also limits the range of the colorbar.

levels = np.arange(-45,45,1)
CS1 = plt.contourf(x,y,z,levels,cmap=cm.get_cmap('RdYlBu_r',len(levels)-1), extend='both')
plt.colorbar(CS1,orientation='vertical',shrink=0.5, format='%.2f')

Hope this helps. Cheers, Trond