python draw parallelepiped

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I am trying to draw a parallelepiped. Actually I started from the python script drawing a cube as:

import numpy as np
from mpl_toolkits.mplot3d import Axes3D
import matplotlib.pyplot as plt

points = np.array([[-1, -1, -1],
                  [1, -1, -1 ],
                  [1, 1, -1],
                  [-1, 1, -1],
                  [-1, -1, 1],
                  [1, -1, 1 ],
                  [1, 1, 1],
                  [-1, 1, 1]])


fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')

r = [-1,1]

X, Y = np.meshgrid(r, r)

ax.plot_surface(X,Y,1, alpha=0.5)
ax.plot_surface(X,Y,-1, alpha=0.5)
ax.plot_surface(X,-1,Y, alpha=0.5)
ax.plot_surface(X,1,Y, alpha=0.5)
ax.plot_surface(1,X,Y, alpha=0.5)
ax.plot_surface(-1,X,Y, alpha=0.5)

ax.scatter3D(points[:, 0], points[:, 1], points[:, 2])

ax.set_xlabel('X')
ax.set_ylabel('Y')
ax.set_zlabel('Z')

plt.show()

In order to obtain a parallelepiped, I have multiplied the points matrix by the following matrix:

P = 

[[2.06498904e-01  -6.30755443e-07   1.07477548e-03]

 [1.61535574e-06   1.18897198e-01   7.85307721e-06]

 [7.08353661e-02   4.48415767e-06   2.05395893e-01]]

as:

Z = np.zeros((8,3))

for i in range(8):

   Z[i,:] = np.dot(points[i,:],P)

Z = 10.0*Z

My idea is then to represent as follows:

ax.scatter3D(Z[:, 0], Z[:, 1], Z[:, 2])

ax.set_xlabel('X')
ax.set_ylabel('Y')
ax.set_zlabel('Z')

plt.show()

And this is what I get:

enter image description here

How can I then put surfaces on these different points to form the parallelepiped (in the way of the cube above)?

4 Answers

Done using matplotlib and coordinate geometry

import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
import numpy as np


def cube_coordinates(edge_len,step_size):
    X = np.arange(0,edge_len+step_size,step_size)
    Y = np.arange(0,edge_len+step_size,step_size)
    Z = np.arange(0,edge_len+step_size,step_size)
    temp=list()
    for i in range(len(X)):
        temp.append((X[i],0,0))
        temp.append((0,Y[i],0))
        temp.append((0,0,Z[i]))
        temp.append((X[i],edge_len,0))
        temp.append((edge_len,Y[i],0))
        temp.append((0,edge_len,Z[i]))
        temp.append((X[i],edge_len,edge_len))
        temp.append((edge_len,Y[i],edge_len))
        temp.append((edge_len,edge_len,Z[i]))
        temp.append((edge_len,0,Z[i]))
        temp.append((X[i],0,edge_len))
        temp.append((0,Y[i],edge_len))
    return temp


edge_len = 10


A=cube_coordinates(edge_len,0.01)
A=list(set(A))
fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
A=zip(*A)
X,Y,Z=list(A[0]),list(A[1]),list(A[2])
ax.scatter(X,Y,Z,c='g')

plt.show()
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