擅长:python、mysql、java
<p>您可以检查是否使用“局部变量”函数定义了变量。或者,如果变量是全局定义的,则应使用“globals”函数</p>
<pre><code>if 'vol1n' not in locals():
vol1n = 0
else:
vol1n=vol1/volsum
if 'vol2n' not in locals():
vol2n = 0
else:
vol2n=vol2/volsum
if 'vol3n' not in locals():
vol3n = 0
else:
vol3n=vol3/volsum
if 'vol4n' not in locals():
vol4n = 0
else:
vol4n=vol4/volsum
</code></pre>