.. _mplot3d-tricontourf3d_demo:

mplot3d example code: tricontourf3d_demo.py
===========================================



.. plot:: /build/tmp/matplotlib-1.4.2/doc/mpl_examples/mplot3d/tricontourf3d_demo.py

::

    """
    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()
    

Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)