python sphere

draw_sphere.py

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

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

u = np.linspace(0, 2 * np.pi, 100)
v = np.linspace(0, np.pi, 100)

x =  np.outer(np.cos(u), np.sin(v))
y =  np.outer(np.sin(u), np.sin(v))
z = np.outer(np.ones(np.size(u)), np.cos(v))

# the equation should be  1/8*x^2 + y^2 + z^2 = 1
ax.plot_surface(math.sqrt(8)*x, y, z, rstride=4, cstride=4, color='b')

plt.show()