ploting filled polygons in python

Question

I have two matrices Tri and V for faces (Nx3) and vertices (Mx3) of polygons that I want to plot. Is there any matplotlib (or any alternative) way to do that? Something similar to Matlab command

patch('faces',Tri,'vertices',V,'facecolor', 
      'flat','edgecolor','none','facealpha',1)

Solution

I'm not exactly sure what matlab does, but you can draw a polygon using matplotlib.patches.Polygon. Adapted from an example in the docs:

import numpy as np

import matplotlib.pyplot as plt
import matplotlib
from matplotlib.patches import Polygon
from matplotlib.collections import PatchCollection

fig, ax = plt.subplots()
patches = []
num_polygons = 5
num_sides = 5

for i in range(num_polygons):
    polygon = Polygon(np.random.rand(num_sides ,2), True)
    patches.append(polygon)

p = PatchCollection(patches, cmap=matplotlib.cm.jet, alpha=0.4)

colors = 100*np.random.rand(len(patches))
p.set_array(np.array(colors))

ax.add_collection(p)

plt.show()