.. 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_polys3d.py: ============================================= Generate polygons to fill under 3D line graph ============================================= Demonstrate how to create polygons which fill the space under a line graph. In this example polygons are semi-transparent, creating a sort of 'jagged stained glass' effect. .. image:: /gallery/mplot3d/images/sphx_glr_polys3d_001.png :class: sphx-glr-single-img .. code-block:: python # This import registers the 3D projection, but is otherwise unused. from mpl_toolkits.mplot3d import Axes3D # noqa: F401 unused import from matplotlib.collections import PolyCollection import matplotlib.pyplot as plt from matplotlib import colors as mcolors import numpy as np # Fixing random state for reproducibility np.random.seed(19680801) def cc(arg): ''' Shorthand to convert 'named' colors to rgba format at 60% opacity. ''' return mcolors.to_rgba(arg, alpha=0.6) def polygon_under_graph(xlist, ylist): ''' Construct the vertex list which defines the polygon filling the space under the (xlist, ylist) line graph. Assumes the xs are in ascending order. ''' return [(xlist[0], 0.), *zip(xlist, ylist), (xlist[-1], 0.)] fig = plt.figure() ax = fig.gca(projection='3d') # Make verts a list, verts[i] will be a list of (x,y) pairs defining polygon i verts = [] # Set up the x sequence xs = np.linspace(0., 10., 26) # The ith polygon will appear on the plane y = zs[i] zs = range(4) for i in zs: ys = np.random.rand(len(xs)) verts.append(polygon_under_graph(xs, ys)) poly = PolyCollection(verts, facecolors=[cc('r'), cc('g'), cc('b'), cc('y')]) ax.add_collection3d(poly, zs=zs, zdir='y') ax.set_xlabel('X') ax.set_ylabel('Y') ax.set_zlabel('Z') ax.set_xlim(0, 10) ax.set_ylim(-1, 4) ax.set_zlim(0, 1) plt.show() .. _sphx_glr_download_gallery_mplot3d_polys3d.py: .. only :: html .. container:: sphx-glr-footer :class: sphx-glr-footer-example .. container:: sphx-glr-download :download:`Download Python source code: polys3d.py ` .. container:: sphx-glr-download :download:`Download Jupyter notebook: polys3d.ipynb ` .. only:: html .. rst-class:: sphx-glr-signature Keywords: matplotlib code example, codex, python plot, pyplot `Gallery generated by Sphinx-Gallery `_