Merge pull request #31 from jgtiu/add/explanation

Add explanation for imshow usage

Author: WeatherGod

solutions/2.2-vmin_vmax_imshow_and_colorbars.py

@@ -15,6 +15,7 @@
 
 # Now you're on your own!
 for ax, data in zip(axes, [data1, data2, data3]):
+    # Display data, explicitly making the colormap cover values from 0 to 3
     im = ax.imshow(data, vmin=0, vmax=3, interpolation='nearest')
 
 fig.colorbar(im, cax=cax, orientation='horizontal')