.. note:: :class: sphx-glr-download-link-note Click :ref:`here ` to download the full example code .. rst-class:: sphx-glr-example-title .. _sphx_glr_gallery_mplot3d_trisurf3d_2.py: =========================== More triangular 3D surfaces =========================== Two additional examples of plotting surfaces with triangular mesh. The first demonstrates use of plot_trisurf's triangles argument, and the second sets a Triangulation object's mask and passes the object directly to plot_trisurf. .. image:: /gallery/mplot3d/images/sphx_glr_trisurf3d_2_001.png :class: sphx-glr-single-img .. code-block:: default import numpy as np import matplotlib.pyplot as plt import matplotlib.tri as mtri # This import registers the 3D projection, but is otherwise unused. from mpl_toolkits.mplot3d import Axes3D # noqa: F401 unused import fig = plt.figure(figsize=plt.figaspect(0.5)) #============ # First plot #============ # Make a mesh in the space of parameterisation variables u and v u = np.linspace(0, 2.0 * np.pi, endpoint=True, num=50) v = np.linspace(-0.5, 0.5, endpoint=True, num=10) u, v = np.meshgrid(u, v) u, v = u.flatten(), v.flatten() # This is the Mobius mapping, taking a u, v pair and returning an x, y, z # triple x = (1 + 0.5 * v * np.cos(u / 2.0)) * np.cos(u) y = (1 + 0.5 * v * np.cos(u / 2.0)) * np.sin(u) z = 0.5 * v * np.sin(u / 2.0) # Triangulate parameter space to determine the triangles tri = mtri.Triangulation(u, v) # Plot the surface. The triangles in parameter space determine which x, y, z # points are connected by an edge. ax = fig.add_subplot(1, 2, 1, projection='3d') ax.plot_trisurf(x, y, z, triangles=tri.triangles, cmap=plt.cm.Spectral) ax.set_zlim(-1, 1) #============ # Second plot #============ # Make parameter spaces radii and angles. n_angles = 36 n_radii = 8 min_radius = 0.25 radii = np.linspace(min_radius, 0.95, n_radii) angles = np.linspace(0, 2*np.pi, n_angles, endpoint=False) angles = np.repeat(angles[..., np.newaxis], n_radii, axis=1) angles[:, 1::2] += np.pi/n_angles # Map radius, angle pairs to x, y, z points. x = (radii*np.cos(angles)).flatten() y = (radii*np.sin(angles)).flatten() z = (np.cos(radii)*np.cos(3*angles)).flatten() # Create the Triangulation; no triangles so Delaunay triangulation created. triang = mtri.Triangulation(x, y) # Mask off unwanted triangles. xmid = x[triang.triangles].mean(axis=1) ymid = y[triang.triangles].mean(axis=1) mask = xmid**2 + ymid**2 < min_radius**2 triang.set_mask(mask) # Plot the surface. ax = fig.add_subplot(1, 2, 2, projection='3d') ax.plot_trisurf(triang, z, cmap=plt.cm.CMRmap) plt.show() .. _sphx_glr_download_gallery_mplot3d_trisurf3d_2.py: .. only :: html .. container:: sphx-glr-footer :class: sphx-glr-footer-example .. container:: sphx-glr-download :download:`Download Python source code: trisurf3d_2.py ` .. container:: sphx-glr-download :download:`Download Jupyter notebook: trisurf3d_2.ipynb ` .. only:: html .. rst-class:: sphx-glr-signature Keywords: matplotlib code example, codex, python plot, pyplot `Gallery generated by Sphinx-Gallery `_