根据2个条件过滤ID

Question

我创建了这个示例数据框：

df <- data.frame(id = c(1,1,1,2,2,2,2,3,3), 
                 car = c("subaru", "audi", "subaru", "toyota", "toyota", "audi", "subaru", "nissan", "nissan"),
                buy_date = c("01/01/2000", "01/01/2001", "01/02/2001", "01/01/2000", "01/05/2000", "01/01/2005", "01/03/2005", "01/01/2000", "02/01/2000"))

df$buy_date <- as.Date(df$buy_date, format="%d/%m/%Y") #it doesnt work properly, but that is not the issue atm

产生这个 df:

id	车	购买日期
1	斯巴鲁	2000-01-01
1	奥迪	2001-01-01
1	斯巴鲁	2001-02-01
2	丰田	2000-01-01
2	丰田	2004-12-01
2	奥迪	2005-01-01
2	斯巴鲁	2005-03-01
3	日产	2000-01-01
3	日产	2000-01-02

我想过滤以下内容：对于每个 ID，如果他/她在 180 天内购买了两种不同类型的汽车，我想保留 ID 中的行。所以它应该返回一个像这样的列表：

id	车	购买日期
1	奥迪	2001-01-01
1	斯巴鲁	2001-02-01
2	丰田	2004-12-01
2	奥迪	2005-01-01
2	斯巴鲁	2005-03-01

希望能帮到你。 提前致谢

Answer 1

您可以使用两个内部联接来完成此操作。请注意，在您的示例数据中，id #2 购买的第二辆丰田汽车与“2004-12-01”日期不匹配，因此我更改了它（请参见下面的输入）

library(dplyr)

df$buy_date <- as.Date(df$buy_date, format="%d/%m/%Y")

inner_join(
  df, 
  inner_join(df,df,by="id", multiple="all") %>% 
    filter(car.x!=car.y, abs(buy_date.x-buy_date.y)<180) %>% 
    select(id, car=car.x, buy_date=buy_date.x) %>% 
    distinct()
)

输出：

  id    car   buy_date
1  1   audi 2001-01-01
2  1 subaru 2001-02-01
3  2 toyota 2004-12-01
4  2   audi 2005-01-01
5  2 subaru 2005-03-01

输入：

structure(list(id = c(1, 1, 1, 2, 2, 2, 2, 3, 3), car = c("subaru", 
"audi", "subaru", "toyota", "toyota", "audi", "subaru", "nissan", 
"nissan"), buy_date = c("01/01/2000", "01/01/2001", "01/02/2001", 
"01/01/2000", "01/12/2004", "01/01/2005", "01/03/2005", "01/01/2000", 
"02/01/2000")), class = "data.frame", row.names = c(NA, -9L))

Answer 2

构造条件然后

filter

ing

library(dplyr)

df %>% 
  mutate(dif = c(diff.Date(buy_date), 0) < 180, 
         dup = ifelse(dif, car, NA), .by = id) %>% 
  filter(!(duplicated(dup) | duplicated(dup, fromLast=T) & !is.na(dup)) & 
           dif, .by = id) %>% 
  select(-c(dif, dup))
  id    car   buy_date
1  1   audi 2001-01-01
2  1 subaru 2001-02-01
3  2 toyota 2000-01-01
4  2   audi 2005-01-01
5  2 subaru 2005-03-01