熊猫:用空格分组替换重复的值,例如

时间:2019-07-24 15:36:17

标签: python pandas pandas-groupby

我的数据框的列中有重复值的组。我想要的是在此类列中仅保留第一项。

我尝试过df = df.groupby(['author', 'key']),但不知道如何正确获取所有行。使用df.first()时,只会打印第一行。

import pandas as pd

lst = [
['juli', 'JIRA-1', 'assignee'],
['juli', 'JIRA-1', 'assignee'],
['nick', 'JIRA-1', 'timespent'], 
['nick', 'JIRA-3', 'status'], 
['nick', 'JIRA-3', 'assignee'],
['tom', 'JIRA-1', 'comment'], 
['tom', 'JIRA-1', 'assignee'], 
['tom', 'JIRA-2', 'status']] 

df = pd.DataFrame(lst, columns =['author', 'key', 'field']) 
#df = df.sort_values(by=['author', 'key'])

>>> df
  author     key      field
0   juli  JIRA-1   assignee
1   juli  JIRA-1   assignee
2   nick  JIRA-1  timespent
3   nick  JIRA-3     status
4   nick  JIRA-3   assignee
5    tom  JIRA-1    comment
6    tom  JIRA-1   assignee
7    tom  JIRA-2     status

我得到了什么

>>> df.groupby(['author', 'key']).first()
                   field
author key
juli   JIRA-1   assignee
nick   JIRA-1  timespent
       JIRA-3     status
tom    JIRA-1    comment
       JIRA-2     status

我想要什么:

juli   JIRA-1   assignee
                assignee
nick   JIRA-1  timespent
       JIRA-3     status
                assignee
tom    JIRA-1    comment
                assignee
       JIRA-2     status

1 个答案:

答案 0 :(得分:1)

好像您需要df.duplicated()来查找重复项,而df.loc[]来分配空格:

df.loc[df.duplicated(['author','key']),['author','key']]=''
print(df)

  author     key      field
0   juli  JIRA-1   assignee
1                  assignee
2   nick  JIRA-1  timespent
3   nick  JIRA-3     status
4                  assignee
5    tom  JIRA-1    comment
6                  assignee
7    tom  JIRA-2     status