擅长:python、mysql、java
<p>你需要玩一下<code>xlim</code>和<code>ylim</code></p>
<p>对我来说,这很有效:</p>
<pre class="lang-py prettyprint-override"><code>import matplotlib.pyplot as plt
import numpy as np
if __name__ == "__main__":
X = np.linspace(-.5, 3, 100)
Y = 15000 - 10 * (X - 2.2) ** 2
Xp = X[-10]
Yp = Y[-10]
plt.plot(X, Y, label='data')
plt.plot(Xp, Yp, marker='o')
plt.vlines(Xp, min(Y), Yp, linestyles='dashed')
plt.hlines(Yp, min(X), Xp, linestyles='dashed')
plt.grid(True)
plt.xlim(min(X), None)
plt.ylim(min(Y), None)
plt.show()
</code></pre>
<p><a href="https://i.stack.imgur.com/O4Zts.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/O4Zts.png" alt="enter image description here"/></a></p>