Planar Voronoi Diagrams

Plotting the generator points



In [1]:

    
import numpy as np
import matplotlib.pyplot as plt
import matplotlib
%matplotlib inline

points = np.array([[1.5, 1.], [3.5, 1.], [5., 2.], [2.5, 3.], [3.5, 1.], 
                   [4., 4.], [5.5, 3.5], [6., 5.5], [7.5, 4], [1.6, 6.]])

fig = plt.figure()
ax = fig.add_subplot('111')
ax.plot(points[:, 0], points[:, 1], 'o', color='k')
ax.set_xlim([-1, 9])
ax.set_ylim([-1, 9])









    Out[1]:





(-1, 9)

Plotting the Voronoi Diagram



In [2]:

    
from scipy.spatial import Voronoi, voronoi_plot_2d
vor = Voronoi(points)

fig = plt.figure()
ax = fig.add_subplot('111')
ax.plot(points[:, 0], points[:, 1], 'o', color='k')
ax.set_xlim([-1, 9])
ax.set_ylim([-1, 9])
voronoi_plot_2d(vor, ax)









    Out[2]:

Plotting a Delaunay triangulation



In [3]:

    
from scipy.spatial import Delaunay
tri = Delaunay(points)

fig = plt.figure()
ax = fig.add_subplot('111')
ax.plot(points[:, 0], points[:, 1], 'o', color='k')
ax.set_xlim([-1, 9])
ax.set_ylim([-1, 9])
ax.triplot(points[:,0], points[:,1], tri.simplices.copy(), color='blue')









    Out[3]:





[<matplotlib.lines.Line2D at 0x7e58ba8>,
 <matplotlib.lines.Line2D at 0x7e58e10>]

Plotting both graphs



In [4]:

    
fig = plt.figure()
ax = fig.add_subplot('111')
ax.plot(points[:, 0], points[:, 1], 'o', color='k')
ax.set_xlim([-1, 9])
ax.set_ylim([-1, 9])
voronoi_plot_2d(vor, ax)
ax.triplot(points[:,0], points[:,1], tri.simplices.copy(), color='blue')









    Out[4]:





[<matplotlib.lines.Line2D at 0x7e225c0>,
 <matplotlib.lines.Line2D at 0x77d24a8>]



In [ ]: