Dorso centrato con frecce

Questo esempio mostra un modo per disegnare un grafico in stile "libro di testo di matematica", in cui le spine ("linee degli assi") sono disegnate in corrispondenza di e e hanno frecce alle estremità.x = 0y = 0

import matplotlib.pyplot as plt
import numpy as np


fig, ax = plt.subplots()
# Move the left and bottom spines to x = 0 and y = 0, respectively.
ax.spines[["left", "bottom"]].set_position(("data", 0))
# Hide the top and right spines.
ax.spines[["top", "right"]].set_visible(False)

# Draw arrows (as black triangles: ">k"/"^k") at the end of the axes.  In each
# case, one of the coordinates (0) is a data coordinate (i.e., y = 0 or x = 0,
# respectively) and the other one (1) is an axes coordinate (i.e., at the very
# right/top of the axes).  Also, disable clipping (clip_on=False) as the marker
# actually spills out of the axes.
ax.plot(1, 0, ">k", transform=ax.get_yaxis_transform(), clip_on=False)
ax.plot(0, 1, "^k", transform=ax.get_xaxis_transform(), clip_on=False)

# Some sample data.
x = np.linspace(-0.5, 1., 100)
ax.plot(x, np.sin(x*np.pi))

plt.show()