import matplotlib.pyplot as plt import numpy as np
x = np.linspace(-3, 3, 50) y1 = 2 * x + 1 y2 = x ** 2
plt.figure() plt.plot(x, y1)
plt.figure(num=3, figsize=(8, 5)) plt.plot(x, y2) # plot the second curve in this figure with certain parameters plt.plot(x, y1, color='red', linewidth=1.0, linestyle='--')