我有以下数据框:
id<-c(1,1,1,3,3,3)
date<-c("23-01-07","27-01-07","30-01-07","11-12-07","12-12-07","01-01-08")
df<-data.frame(id,date)
df$date2<-as.Date(as.character(df$date), format = "%d-%m-%y")
id date date2
1 23-01-07 2007-01-23
1 27-01-07 2007-01-27
1 30-01-07 2007-01-30
3 11-12-07 2007-12-11
3 12-12-07 2007-12-12
3 01-01-08 2008-01-01
现在我需要计算每个id的交易之间的购买时间(一个客户的每笔交易与同一客户之前的交易之间的天数);这样我得到以下结果:
id date date2 interpurchase.time
1 23-01-07 2007-01-23 0
1 27-01-07 2007-01-27 4
1 30-01-07 2007-01-30 3
3 11-12-07 2007-12-11 0
3 12-12-07 2007-12-12 1
3 01-01-08 2008-01-01 20
我想知道是否有人可以帮助我解决这个问题。