How I can filter data just for one group in r?-CodePudding

I want to filter a dataframe for dates greater than or equal to something, but only for certain rows according to a condition, without affecting the rest of the observations.

I am not sure how to do this.

This is the code I have so far:

library(dplyr)

dat <- tibble(id = rep(LETTERS[1:4], 10),
              date_a = c(
                seq(as.Date("2020-01-01"), as.Date("2021-08-01"), "months"),
                seq(as.Date("2020-01-01"), as.Date("2021-08-01"), "months")
              ))

dat |>
  filter(date_a >= as.Date("2021-01-01"))

CodePudding user response：

We may use

tibble(
  id  = rep(LETTERS[1:4],10),
  date_a  = c(seq(as.Date("2020-01-01"), as.Date("2021-08-01"), "months"),
        seq(as.Date("2020-01-01"), as.Date("2021-08-01"), "months")
        )
)  |> 
    filter((date_a  >= as.Date("2021-01-01") & id == 'A')| (id != 'A'))