擅长:python、mysql、java
<p>您还可以使用<code>groupby.transform('first')</code>,如中所示</p>
<pre><code>df['match'] = (
df.groupby('query')['HPSame'].transform('first')
.reset_index(drop=True)
)
</code></pre>
<p>输出</p>
<pre><code> query subject HPSame match
0 WP_77.1 WP_706.1 HPS_1 HPS_1
1 WP_78.1 WP_46.1 HPS_2 HPS_2
2 WP_57.1 WP_26.1 HPS_3 HPS_3
3 WP_57.1 WP_627.1 HPS_4 HPS_3
4 WP_15.1 WP_16.1 HPS_5 HPS_5
5 WP_15.1 WP_17.1 HPS_6 HPS_5
6 WP_15.1 WP_63.1 HPS_7 HPS_5
7 WP_15.1 WP_61.1 HPS_8 HPS_5
8 WP_15.1 WP_56.1 HPS_9 HPS_5
9 WP_40.1 WP_11.1 HPS_10 HPS_10
</code></pre>