擅长:python、mysql、java
<p>我会建立一个字典和地图:</p>
<pre><code>d = {v:'southern' for v in southern}
d.update({v:'northern' for v in northern})
df['davalue'].groupby(df['name'].map(d)).sum()
</code></pre>
<p>输出:</p>
<pre><code>name
northern 15
southern 10
Name: davalue, dtype: int64
</code></pre>