查找组中的最大值，并将其他列的值添加到 python pandas 中的新行

Question

我有桌子：

person	score	Job type
person 1	6.5	job 1
person 1	4.3	job 2
person 2	1.2	job 1
person 2	3.4	job 2
person 2	4.3	job 3

我想添加一个工作类型的列，得分最高，如下所示：

person	score	Job type	Higest score
person 1	6.5	job 1	job 1
person 1	4.3	job 2	job 1
person 2	1.2	job 1	job 3
person 2	3.4	job 2	job 3
person 3	4.3	job 3	job 3

知道如何实现这一目标吗？

Answer 1

您可以使用：

mask=df.sort_values('score').groupby('person').tail(1).rename(columns={'Job type':'Higest_score'})

final=df.merge(mask[['person','Higest_score']],how='left')
final
'''
    person      score   Job type    Higest_score
0   person 1    6.5     job 1       job 1
1   person 1    4.3     job 2       job 1
2   person 2    1.2     job 1       job 3
3   person 2    3.4     job 2       job 3
4   person 2    4.3     job 3       job 3

'''