擅长:python、mysql、java
<p>或者简单地使用loc作为@COLDSPEED答案的选项3</p>
<pre><code>cond = (df['gender'].isnull()) & (df['title'].str.contains('lip'))
df.loc[cond, 'gender'] = 'women'
category gender sub-category title
0 health&beauty women makeup lipbalm
1 health&beauty women makeup lipstick
2 NaN women NaN lipgloss
</code></pre>