<p>或者:</p>
<pre><code>df.join(df.T.groupby(df.T.index.str.split("_").str[0]).sum().T.iloc[:,1:].add_suffix('_Total'))
Date David_Added David_Removed Malik_Added Malik_Removed \
0 02/19/2019 3 1 39 41
1 02/18/2019 0 0 8 6
2 02/16/2019 0 0 0 0
3 02/15/2019 0 0 0 0
4 02/14/2019 0 0 0 0
5 02/13/2019 0 0 0 0
6 02/12/2019 0 0 0 0
7 02/11/2019 0 0 0 0
8 02/08/2019 0 0 0 0
9 02/07/2019 0 0 0 0
Meghan_Added Meghan_Removed Sucely_Added Sucely_Removed David_Total \
0 1 6 14 24 4
1 0 3 0 0 0
2 0 0 0 0 0
3 0 0 0 0 0
4 0 0 0 0 0
5 0 0 0 0 0
6 0 0 0 0 0
7 0 0 0 0 0
8 0 0 0 0 0
9 0 0 0 0 0
Malik_Total Meghan_Total Sucely_Total
0 80 7 38
1 14 3 0
2 0 0 0
3 0 0 0
4 0 0 0
5 0 0 0
6 0 0 0
7 0 0 0
8 0 0 0
9 0 0 0
</code></pre>