擅长:python、mysql、java
<p>我认为这与<code>pylab</code>状态机和作用域有关。</p>
<p>一个更好的做法是这样做(显式比隐式好):</p>
<pre><code>import numpy as np
import matplotlib.pyplot as plt
def fct():
f = plt.figure()
ax = f.add_subplot(111)
x, y = np.mgrid[0:5,0:5]
z = np.sin(x**2+y**2)
mesh = ax.pcolormesh(x, y ,z)
return ax, mesh
ax, mesh = fct()
plt.colorbar(mesh, ax=ax)
</code></pre>