# 3D-vectorveld

import matplotlib.pyplot as plt
import numpy as np

x, y, z = np.meshgrid (np.arange (-1, 1, 0.25), np.arange (-1, 1, 0.25), np.arange (-1, 1, 0.25))
 
u = x**2 + y**2
v = - 2 * x * y
w = x * y * z

plt.figure (figsize = (8, 8))

ax = plt.axes (projection = "3d")

q = ax.quiver (x, y, z, u, v, w, color = "royalblue", length = 0.25)

plt.show ()