python - 如何在熊猫数据框中创建一个逗号分隔列表作为新列

Question

我有如下数据框（df）。

如果有的话，我也想跳过空值。

输入

 A            B              C   
[e-mail]   [e-mail]    [e-mail]
[e-mail]
[e-mail]   [e-mail]    [e-mail]
[e-mail]                  [e-mail]
               [e-mail]   [e-mail]

输出

 A            B              C             Merged
[e-mail]   [e-mail]    [e-mail]    [e-mail],[e-mail],[e-mail]
[e-mail]                                [e-mail]
[e-mail]   [e-mail]    [e-mail]   [e-mail],[e-mail],[e-mail]
[e-mail]                  [e-mail]   [e-mail],[e-mail]
               [e-mail]   [e-mail]   [e-mail],[e-mail]

如何使用熊猫来做到这一点？

标签： pythonpandasdataframe

Answer 1

使用（更新以处理 '' vs NaN）：

df.replace('', np.nan).apply(lambda x: x.str.cat(sep=', '), axis=1)

输出：

0     [e-mail], [e-mail], [e-mail]
1                              [e-mail]
2    [e-mail], [e-mail], [e-mail]
3                 [e-mail], [e-mail]
4                 [e-mail], [e-mail]
dtype: object

喜欢，

df['merged'] = df.replace('', np.nan).apply(lambda x: x.str.cat(sep=', '), axis=1)

输出：

             A            B            C                                 merged
0  [e-mail]  [e-mail]   [e-mail]   [e-mail], [e-mail], [e-mail]
1  [e-mail]          NaN          NaN                            [e-mail]
2  [e-mail]  [e-mail]  [e-mail]  [e-mail], [e-mail], [e-mail]
3  [e-mail]          NaN  [e-mail]               [e-mail], [e-mail]
4          NaN  [e-mail]  [e-mail]               [e-mail], [e-mail]