Plotting 3D Polygons in python-matplotlib

Question:

I was unsuccessful browsing web for a solution for the following simple question:

How to draw 3D polygon (say a filled rectangle or triangle) using vertices values?
I have tried many ideas but all failed, see:

from mpl_toolkits.mplot3d import Axes3D
from matplotlib.collections import PolyCollection
import matplotlib.pyplot as plt
fig = plt.figure()
ax = Axes3D(fig)
x = [0,1,1,0]
y = [0,0,1,1]
z = [0,1,0,1]
verts = [zip(x, y,z)]
ax.add_collection3d(PolyCollection(verts),zs=z)
plt.show()

I appreciate in advance any idea/comment.

Updates based on the accepted answer:

import mpl_toolkits.mplot3d as a3
import matplotlib.colors as colors
import pylab as pl
import numpy as np

ax = a3.Axes3D(pl.figure())
for i in range(10000):
    vtx = np.random.rand(3,3)
    tri = a3.art3d.Poly3DCollection([vtx])
    tri.set_color(colors.rgb2hex(np.random.rand(3)))
    tri.set_edgecolor('k')
    ax.add_collection3d(tri)
pl.show()

Here is the result:
enter image description here

Asked By: Developer

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Answers:

I think you’ve almost got it. Is this what you want?

from mpl_toolkits.mplot3d import Axes3D
from mpl_toolkits.mplot3d.art3d import Poly3DCollection
import matplotlib.pyplot as plt
fig = plt.figure()
ax = Axes3D(fig, auto_add_to_figure=False)
fig.add_axes(ax)
x = [0,1,1,0]
y = [0,0,1,1]
z = [0,1,0,1]
verts = [list(zip(x,y,z))]
ax.add_collection3d(Poly3DCollection(verts))
plt.show()

alt text
You might also be interested in art3d.pathpatch_2d_to_3d.

Answered By: DSM

The above solution is for Python 2, and gives an error ‘TypeError: object of type ‘zip’ has no len()’ when run with python 3.

See Plotting 3D Polygons in Python 3 for discussion on updating this to Python 3.

Here’s some working code from there:

from mpl_toolkits.mplot3d import Axes3D
from mpl_toolkits.mplot3d.art3d import Poly3DCollection
import matplotlib.pyplot as plt

fig = plt.figure()
ax = Axes3D(fig)
x = [0, 1, 1, 0]
y = [0, 0, 1, 1]
z = [0, 1, 0, 1]
verts = [list(zip(x, y, z))]
print(verts)
ax.add_collection3d(Poly3DCollection(verts), zs='z')
plt.show()
Answered By: Alex Kritchevsky
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