pandas：如何将行分组到新列中

Question

我有一个简单的数据集，形式如下：

author_id,Publisher,Title
1,Archie Publications,Archie
1,Marvel,A-Team
1,NOW,The Green Hornet
2,Archie Publications,Betty & Veronica
2,Marvel,Absolute Carnage
2,NOW,Little Monsters
2,NOW,The Green Hornet
2,NOW,Kata
3,Archie Publications,Archie & Jughead
3,Marvel,Absolute Carnage
3,NOW,Fright Night
4,Archie Publications,Archie
4,Archie Publications,Jughead
4,Marvel,A+X
5,Marvel,A-Next
5,NOW,The Green Hornet
5,NOW,Little Monsters

我可以使用 df3=pandas.read_csv("comics.csv",index_col=['author_id','Publisher']) 成功读取它，这给了我（预期的）数据帧：

我想要的是将行“组合”到一个新列中，将其命名为 titles，以便生成的数据帧采用以下形式：

author_id             publisher titles
        1   Archie Publications [Archie]
        1                Marvel [A-Team]
        1                   NOW [The Green Hornet]
        2   Archie Publications [Betty & Veronica]
        2                Marvel [Absolute Carnage]
        3                   NOW [Little Monsters, The Green Hornet, Kata]
  ...
        4   Archie Publications [Archie, Jughead]
  ...

例如对于作者 #2，他们现在制作了 3 个标题，所以我想要在新列“标题”中列出这些标题。

我不知道如何进行这种转换..有什么建议吗？

Answer 1

我想这就是你想要的

df.groupby(['author_id', 'Publisher']).agg({'Title': list})

                                                                   Title
author_id Publisher                                                     
1         Archie Publications                                   [Archie]
          Marvel                                                [A-Team]
          NOW                                         [The Green Hornet]
2         Archie Publications                         [Betty & Veronica]
          Marvel                                      [Absolute Carnage]
          NOW                  [Little Monsters, The Green Hornet, Kata]
3         Archie Publications                         [Archie & Jughead]
          Marvel                                      [Absolute Carnage]
          NOW                                             [Fright Night]
4         Archie Publications                          [Archie, Jughead]
          Marvel                                                   [A+X]
5         Marvel                                                [A-Next]
          NOW                        [The Green Hornet, Little Monsters]

pandas：如何将行分组到新列中

pandas: how to group rows into a new column

python

pandas

data-wrangling