根据列值重复 Pandas DataFrame 中的行
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Repeat rows in a pandas DataFrame based on column value
提问by abutremutante
I have the following df:
我有以下 df：
code . role . persons
123 . Janitor . 3
123 . Analyst . 2
321 . Vallet . 2
321 . Auditor . 5
The first line means that I have 3 persons with the role Janitors. My problem is that I would need to have one line for each person. My df should look like this:
第一行表示我有 3 个角色为 Janitors 的人。我的问题是我需要为每个人设置一行。我的 df 应该是这样的：
df:
code . role . persons
123 . Janitor . 3
123 . Janitor . 3
123 . Janitor . 3
123 . Analyst . 2
123 . Analyst . 2
321 . Vallet . 2
321 . Vallet . 2
321 . Auditor . 5
321 . Auditor . 5
321 . Auditor . 5
321 . Auditor . 5
321 . Auditor . 5
How could I do that using pandas?
我怎么能用Pandas做到这一点？
回答by YOBEN_S
reindex+ repeat
reindex+ repeat
df.reindex(df.index.repeat(df.persons))
Out[951]:
code . role ..1 persons
0 123 . Janitor . 3
0 123 . Janitor . 3
0 123 . Janitor . 3
1 123 . Analyst . 2
1 123 . Analyst . 2
2 321 . Vallet . 2
2 321 . Vallet . 2
3 321 . Auditor . 5
3 321 . Auditor . 5
3 321 . Auditor . 5
3 321 . Auditor . 5
3 321 . Auditor . 5
PS: you can add.reset_index(drop=True)to get the new index
PS：可以添加.reset_index(drop=True)获取新索引
回答by cs95
Wen's solution is really nice and intuitive. Here's an alternative, calling repeaton df.values.
Wen 的解决方案非常好且直观。这里有一个替代方案，呼吁repeat上df.values。
df
code role persons
0 123 Janitor 3
1 123 Analyst 2
2 321 Vallet 2
3 321 Auditor 5
pd.DataFrame(df.values.repeat(df.persons, axis=0), columns=df.columns)
code role persons
0 123 Janitor 3
1 123 Janitor 3
2 123 Janitor 3
3 123 Analyst 2
4 123 Analyst 2
5 321 Vallet 2
6 321 Vallet 2
7 321 Auditor 5
8 321 Auditor 5
9 321 Auditor 5
10 321 Auditor 5
11 321 Auditor 5
