>>> """
=======================
Plot 2D data on 3D plot
=======================

Demonstrates using ax.plot's zdir keyword to plot 2D data on
selective axes of a 3D plot.
"""
... 
... import numpy as np
... import matplotlib.pyplot as plt
... 
... ax = plt.figure().add_subplot(projection='3d')
... 
... # Plot a sin curve using the x and y axes.
... x = np.linspace(0, 1, 100)
... y = np.sin(x * 2 * np.pi) / 2 + 0.5
... ax.plot(x, y, zs=0, zdir='z', label='curve in (x, y)')
... 
... # Plot scatterplot data (20 2D points per colour) on the x and z axes.
... colors = ('r', 'g', 'b', 'k')
... 
... # Fixing random state for reproducibility
... np.random.seed(19680801)
... 
... x = np.random.sample(20 * len(colors))
... y = np.random.sample(20 * len(colors))
... c_list = []
... for c in colors:
...     c_list.extend([c] * 20)
... # By using zdir='y', the y value of these points is fixed to the zs value 0
... # and the (x, y) points are plotted on the x and z axes.
... ax.scatter(x, y, zs=0, zdir='y', c=c_list, label='points in (x, z)')
... 
... # Make legend, set axes limits and labels
... ax.legend()
... ax.set_xlim(0, 1)
... ax.set_ylim(0, 1)
... ax.set_zlim(0, 1)
... ax.set_xlabel('X')
... ax.set_ylabel('Y')
... ax.set_zlabel('Z')
... 
... # Customize the view angle so it's easier to see that the scatter points lie
... # on the plane y=0
... ax.view_init(elev=20., azim=-35)
... 
... plt.show()
...