擅长:python、mysql、java
<p>IIUC <code>stack</code>带{<cd2>}</p>
<pre><code>df.set_index('IDs').stack(dropna=False).astype(object).reset_index()
Out[915]:
IDs level_1 0
0 Ellie AABC 12
1 Ellie ABC6 NaN
2 Ellie YHG.8 48.7
3 Ellie D78Ha 33
4 Kate AABC 98
5 Kate ABC6 34
6 Kate YHG.8 21
7 Kate D78Ha 76.36
8 Joe AABC 22
9 Joe ABC6 53
10 Joe YHG.8 49
11 Joe D78Ha NaN
12 Van AABC 77
13 Van ABC6 NaN
14 Van YHG.8 40
15 Van D78Ha 12.1
16 Xavier AABC NaN
17 Xavier ABC6 NaN
18 Xavier YHG.8 NaN
19 Xavier D78Ha 88.85
</code></pre>