擅长:python、mysql、java
<p>可以将<a href="https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.groupby.html" rel="nofollow noreferrer">^{<cd1>}</a>与<a href="https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.nunique.html" rel="nofollow noreferrer">^{<cd2>}</a>结合使用</p>
<p>代码如下:</p>
<pre><code>df.groupby('Month').id.nunique().reset_index()
</code></pre>
<p>结果如下所示:</p>
<pre><code> Month id
0 1-2020 10
1 10-2020 7
2 11-2020 7
3 2-2020 5
4 3-2020 7
5 4-2020 5
6 5-2020 4
7 6-2020 7
8 7-2020 5
9 8-2020 7
10 9-2020 7
</code></pre>