R dplyr if date difference is less

user_14504991 0
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I have this dataframe

dt <-
  data.frame(
    date = c(as.Date("2022-03-01"), as.Date("2022-03-02"), as.Date("2022-03-08"), as.Date("2022-03-08"), as.Date("2022-04-01"), as.Date("2022-04-10"))
    )

My goal is to create new column in dplyr and assign 1/0 depending on date difftime in days. In case that difference is lower than 7, 0 schould be assigned and vice versa. Thus desired result is.

result <-
  data.frame(
    date = c(as.Date("2022-03-01"), as.Date("2022-03-02"), as.Date("2022-03-08"), as.Date("2022-03-08"), as.Date("2022-04-01"), as.Date("2022-04-10")),
    cache = c(0, 1, 0, 1, 0, 0)
  )
dplyr r
1 Answers

Here is a way with diff. It works because objects of class "Date" record the integer number of days since an origin and are internally integers.

suppressPackageStartupMessages(library(dplyr))

dt <-
  data.frame(
    date = c(as.Date("2022-03-01"), as.Date("2022-03-02"), as.Date("2022-03-08"), as.Date("2022-03-08"), as.Date("2022-04-01"), as.Date("2022-04-10"))
  )

dt %>%
  mutate(cache = c(0, diff(date) >= 7L))
#>         date cache
#> 1 2022-03-01     0
#> 2 2022-03-02     0
#> 3 2022-03-08     0
#> 4 2022-03-08     0
#> 5 2022-04-01     1
#> 6 2022-04-10     1

Created on 2022-07-22 by the reprex package (v2.0.1)

Edit

Following the exchange of comments, the code below seems to be the right one.

suppressPackageStartupMessages(library(dplyr))

dt <-
  data.frame(
    date = c(as.Date("2022-03-01"), as.Date("2022-03-02"), as.Date("2022-03-08"), as.Date("2022-03-08"), as.Date("2022-04-01"), as.Date("2022-04-10"))
  )

dt %>%
  mutate(
    cache = as.integer(date - first(date) >= 7L)
  )
#>         date cache
#> 1 2022-03-01     0
#> 2 2022-03-02     0
#> 3 2022-03-08     1
#> 4 2022-03-08     1
#> 5 2022-04-01     1
#> 6 2022-04-10     1

Created on 2022-07-22 by the reprex package (v2.0.1)

Note:

In the creation of the dates vector, it would have been simpler to call as.Date only once.

as.Date(c("2022-03-01", "2022-03-02", "2022-03-08", "2022-03-08", "2022-04-01", "2022-04-10"))
user_82454060
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