根据其他组的值选择行之前和之后的行-熊猫

Question

import pandas as pd
import numpy as np

raw_data = {'Country':['UK','UK','UK','UK','UK','UK','UK','UK','UK','UK','UK','UK'],
    'Product':['A','A','A','A','B','B','B','B','B','B','B','B'],
            'Week': [1,2,3,4,1,2,3,4,5,6,7,8], 
       'val': [5,4,3,1,5,6,7,8,9,10,11,12]
    }

have = pd.DataFrame(raw_data, columns = ['Country','Product','Week', 'val'])

print(have)

我想选择产品A的最后一周之前和之后的行，即第4周和产品B的行应为4行，第3周之前应为3行，第5周之后应为5,6，包括第4周，因此总计为4。这是通缉的输出

Answer 1

IIUC：

df = pd.DataFrame(raw_data, columns=['Country', 'Product', 'Week', 'val'])

max_week = df.loc[df["Product"].eq("A"),"Week"].max()

print (df[df["Product"].eq("A")|((df["Week"]>=max_week-1)&(df["Week"]<=max_week+2))])

#
  Country Product  Week  val
0      UK       A     1    5
1      UK       A     2    4
2      UK       A     3    3
3      UK       A     4    1
6      UK       B     3    7
7      UK       B     4    8
8      UK       B     5    9
9      UK       B     6   10