python - 带日期限制的总信息

Question

我只想根据日期范围按 ID 和给定值求和总计

我尝试过这个:

days=(360)
import datetime 
import pandas as pd
group = None
df=pd.read_excel(r'C:\Users\xxxx\Desktop\xxxxx.xlsx')
for i in days:
        D = ((datetime.datetime.now()-datetime.timedelta(days=i)))
        B = D <= df['DATE']
        group = df.groupby('ID')['VALUE'].filter(lambda x: B ).sum()

df:

DATE       ID  VALUE
2019-01-01 1    10
2019-02-01 2    15
2019-03-01 1    12

但是有一个错误

TypeError: the filter must return a boolean result

即使B的类型是bool

我需要的结果是:

    ID Value
     1  22
     2  15

Answer 1

我相信您需要按 boolean indexing 进行过滤在groupby之前:

 group = df[B].groupby('ID')['VALUE'].sum()

或者:

 D = ((datetime.datetime.now()-datetime.timedelta(days=i)))
 B = df.loc[D <= df['DATE'], 'VALUE']
 group = B.groupby(df['ID']).sum()