import numpy as np import matplotlib.pyplot as plt x = np.linspace(0, 20, 1000) y1 = np.sin(x) y2 = np.cos(x) plt.plot(x, y1, "-b", label="sine") plt.plot(x, y2, "-r", label="cosine") plt.legend(loc="upper left") plt.ylim(-1.5, 2.0) plt.show()