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        "\n# Triangular 3D contour plot\n\nContour plots of unstructured triangular grids.\n\nThe data used is the same as in the second plot of :doc:`trisurf3d_2`.\n:doc:`tricontourf3d` shows the filled version of this example.\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
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      "source": [
        "import matplotlib.pyplot as plt\nimport numpy as np\n\nimport matplotlib.tri as tri\n\nn_angles = 48\nn_radii = 8\nmin_radius = 0.25\n\n# Create the mesh in polar coordinates and compute x, y, z.\nradii = np.linspace(min_radius, 0.95, n_radii)\nangles = np.linspace(0, 2*np.pi, n_angles, endpoint=False)\nangles = np.repeat(angles[..., np.newaxis], n_radii, axis=1)\nangles[:, 1::2] += np.pi/n_angles\n\nx = (radii*np.cos(angles)).flatten()\ny = (radii*np.sin(angles)).flatten()\nz = (np.cos(radii)*np.cos(3*angles)).flatten()\n\n# Create a custom triangulation.\ntriang = tri.Triangulation(x, y)\n\n# Mask off unwanted triangles.\ntriang.set_mask(np.hypot(x[triang.triangles].mean(axis=1),\n                         y[triang.triangles].mean(axis=1))\n                < min_radius)\n\nax = plt.figure().add_subplot(projection='3d')\nax.tricontour(triang, z, cmap=plt.cm.CMRmap)\n\n# Customize the view angle so it's easier to understand the plot.\nax.view_init(elev=45.)\n\nplt.show()"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        ".. tags::\n   plot-type: 3D, plot-type: specialty,\n   level: intermediate\n\n"
      ]
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