擅长:python、mysql、java
<p>这可能会奏效:</p>
<pre><code>import pandas as pd
ddict = {
'col1':['A','A','B','X'],
'col2':['A','A','B','X'],
'col3':['A','A','B','X'],
}
df = pd.DataFrame(ddict)
df.loc[:, ['col1', 'col2', 'col3']].rename(columns={"col3":"anothercol"}).assign(newcol=3)
</code></pre>
<p>结果:</p>
<pre><code> col1 col2 anothercol newcol
0 A A A 3
1 A A A 3
2 B B B 3
3 X X X 3
</code></pre>