You can do this with quiver, but it's a little tricky to get the keyword arguments right.
import numpy as np
import matplotlib.pyplot as plt
x = np.linspace(0, 2*np.pi, 10)
y = np.sin(x)
plt.figure()
plt.quiver(x[:-1], y[:-1], x[1:]-x[:-1], y[1:]-y[:-1], scale_units='xy', angles='xy', scale=1)
plt.show()
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