Question

给定一个多索引DataFrame，我想组合重复的索引对并将它们的值列为逗号分隔列表。例如，输入：

df = pd.DataFrame({'Last Name' : ['Deere','Deere','Foo'   ,'Foo'  ,'Man'   ],
                   'First Name': ['John' ,'Jane' ,'Kung'  ,'Kung' ,'Karate'],
                   'Value1':     [ 1     , 2     , 3      , 4     , 5      ],
                   'Value2':     ['Green','Blue' ,'Yellow','Black','Purple']})

df.set_index(['Last Name','First Name'],inplace=True)

提供：

                          Value1    Value2
Last Name   First Name      
Deere       John          1         Green
            Jane          2         Blue
Foo         Kung          3         Yellow
            Kung          4         Black
Man         Karate        5         Purple

我想将其转换为以下DataFrame：

                          Value1    Value2
Last Name   First Name      
Deere       John          1         Green
            Jane          2         Blue
Foo         Kung          3,4       Yellow,Black
Man         Karate        5         Purple

Answer 1

您可以先按astype将列Value1转换为string，然后Last Name将First Name和join转换为groupby } df['Value1'] = df['Value1'].astype(str) result = df.groupby(level=['Last Name','First Name'], sort=False).agg( ','.join) print result Value1 Value2 Last Name First Name Deere John 1 Green Jane 2 Blue Foo Kung 3,4 Yellow,Black Man Karate 5 Purple：

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将Multiindex DataFrame的行合并到逗号分隔列表中

1 个答案: