This function computes the time interval between consecutive values
in a reference date column, optionally within groups.
Usage
calculate_date_intervals(data, ref_date, group_vars = NULL)
Arguments
- data
A data frame or tibble.
- ref_date
Name of the column containing reference dates.
- group_vars
Optional grouping variables (e.g., `id`, `country`, or `c(id, country)`).
Value
The original data with an additional set of columns indicating the
difference between consecutive reference dates.
Examples
library(tibble)
df <- tibble(id = c(1, 1, 1, 2, 2),
ref_date = as.Date(c("2020-01-01", "2021-01-01", "2023-01-01",
"2020-06-01", "2020-12-01")))
calculate_date_intervals(df, "ref_date", "id")
#> id interval_days
#> <num> <num>
#> 1: 1 NA
#> 2: 1 366
#> 3: 1 730
#> 4: 2 NA
#> 5: 2 183
