>>> """
==========================
3D voxel / volumetric plot
==========================

Demonstrates plotting 3D volumetric objects with `.Axes3D.voxels`.
"""
... 
... import matplotlib.pyplot as plt
... import numpy as np
... 
... 
... # prepare some coordinates
... x, y, z = np.indices((8, 8, 8))
... 
... # draw cuboids in the top left and bottom right corners, and a link between
... # them
... cube1 = (x < 3) & (y < 3) & (z < 3)
... cube2 = (x >= 5) & (y >= 5) & (z >= 5)
... link = abs(x - y) + abs(y - z) + abs(z - x) <= 2
... 
... # combine the objects into a single boolean array
... voxelarray = cube1 | cube2 | link
... 
... # set the colors of each object
... colors = np.empty(voxelarray.shape, dtype=object)
... colors[link] = 'red'
... colors[cube1] = 'blue'
... colors[cube2] = 'green'
... 
... # and plot everything
... ax = plt.figure().add_subplot(projection='3d')
... ax.voxels(voxelarray, facecolors=colors, edgecolor='k')
... 
... plt.show()
...