Add Axes3D.contourf example

dmcdougall · dmcdougall · commit 3832496a9f37 · 2013-06-21T23:58:04.000-05:00
diff --git a/examples/mplot3d/tricontourf3d_demo.py b/examples/mplot3d/tricontourf3d_demo.py
@@ -0,0 +1,36 @@
+"""
+Contour plots of unstructured triangular grids.
+"""
+import matplotlib.pyplot as plt
+from mpl_toolkits.mplot3d import Axes3D
+import matplotlib.tri as tri
+import numpy as np
+import math
+
+# First create the x and y coordinates of the points.
+n_angles = 48
+n_radii = 8
+min_radius = 0.25
+radii = np.linspace(min_radius, 0.95, n_radii)
+
+angles = np.linspace(0, 2*math.pi, n_angles, endpoint=False)
+angles = np.repeat(angles[...,np.newaxis], n_radii, axis=1)
+angles[:,1::2] += math.pi/n_angles
+
+x = (radii*np.cos(angles)).flatten()
+y = (radii*np.sin(angles)).flatten()
+z = (np.cos(radii)*np.cos(angles*3.0)).flatten()
+
+# Create a custom triangulation
+triang = tri.Triangulation(x, y)
+
+# Mask off unwanted triangles.
+xmid = x[triang.triangles].mean(axis=1)
+ymid = y[triang.triangles].mean(axis=1)
+mask = np.where(xmid*xmid + ymid*ymid < min_radius*min_radius, 1, 0)
+triang.set_mask(mask)
+
+plt.figure()
+plt.gca(projection='3d')
+plt.tricontourf(triang, z)
+plt.show()
