How to create a legend for 3D bar in matplotlib?
You need to use a proxy artist where legends are not supported.
This code:
from mpl_toolkits.mplot3d import Axes3Dimport matplotlib.pyplot as pltimport numpy as npfig = plt.figure()ax = fig.add_subplot(111, projection='3d')x, y = np.random.rand(2, 100) * 4hist, xedges, yedges = np.histogram2d(x, y, bins=4)elements = (len(xedges) - 1) * (len(yedges) - 1)xpos, ypos = np.meshgrid(xedges[:-1]+0.25, yedges[:-1]+0.25)xpos = xpos.flatten()ypos = ypos.flatten()zpos = np.zeros(elements)dx = 0.5 * np.ones_like(zpos)dy = dx.copy()dz = hist.flatten()ax.bar3d(xpos[:8], ypos[:8], zpos[:8], dx, dy, dz, color='b', zsort='average')blue_proxy = plt.Rectangle((0, 0), 1, 1, fc="b")ax.bar3d(xpos[8:], ypos[8:], zpos[8:], dx, dy, dz, color='r', zsort='average')red_proxy = plt.Rectangle((0, 0), 1, 1, fc="r")ax.legend([blue_proxy,red_proxy],['cars','bikes'])plt.show()produces this: