# Vlak + krommes

import matplotlib.pyplot as plt
import numpy as np

from mpl_toolkits import mplot3d

plt.figure (figsize = (10, 10))

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

x1 = np.arange (-5, 5, 0.1)
y1 = np.arange (-5, 5, 0.1)

x1, y1 = np.meshgrid (x1, y1)
z1 = - np.exp (- x1**2 - y1**2)

t = np.linspace (-5, 5, 100)
x2 = t

y2a = 1.3 - (np.sign (t) + 1) * t / 8
z2a = - np.exp (- x2**2 - y2a**2)

ax.plot3D (x2, y2a, z2a, color = "gold", zorder = 3)

ax.plot_surface (x1, y1, z1, color = "lightgreen")

ax.set_zlim3d (-2, 0)

plt.axis ("off")
plt.show ()