# 3D-vectorveld import matplotlib.pyplot as plt import numpy as np x, y, z = np.meshgrid (np.arange (-2, 2, 0.5), np.arange (-2, 2, 0.5), np.arange (-2, 2, 0.5)) u = x**2 v = y**2 w = z plt.figure (figsize = (8, 8)) ax = plt.axes (projection = "3d") q = ax.quiver (x, y, z, u, v, w, color = "blue", length = 0.2) plt.show ()