IIUC:
In [227]: df.applymap(len).idxmax(axis=1)
Out[227]:
0 positive
1 negative
2 negative
dtype: object
在包含最长列表的Pandas DF中找到列的名称
IIUC:
In [227]: df.applymap(len).idxmax(axis=1)
Out[227]:
0 positive
1 negative
2 negative
dtype: object