我试图找到一种更有效的方法,根据特定列(id)查找数据框中的重叠数据范围(每行提供的开始/结束日期).
Dataframe在"from"列上排序
我认为有一种方法可以像我一样避免"双重"应用功能......
import pandas as pd
from datetime import datetime
df = pd.DataFrame(columns=['id','from','to'], index=range(5), \
data=[[878,'2006-01-01','2007-10-01'],
[878,'2007-10-02','2008-12-01'],
[878,'2008-12-02','2010-04-03'],
[879,'2010-04-04','2199-05-11'],
[879,'2016-05-12','2199-12-31']])
df['from'] = pd.to_datetime(df['from'])
df['to'] = pd.to_datetime(df['to'])
id from to
0 878 2006-01-01 2007-10-01
1 878 2007-10-02 2008-12-01
2 878 2008-12-02 2010-04-03
3 879 2010-04-04 2199-05-11
4 879 2016-05-12 2199-12-31
我使用"apply"函数循环所有组,在每个组中,我每行使用"apply":
def check_date_by_id(df):
df['prevFrom'] = df['from'].shift()
df['prevTo'] = df['to'].shift()
def check_date_by_row(x):
if pd.isnull(x.prevFrom) or pd.isnull(x.prevTo):
x['overlap'] = False
return x
latest_start = max(x['from'], x.prevFrom)
earliest_end = min(x['to'], x.prevTo)
x['overlap'] = …