Returns a data frame with the start ("spring") and end ("fall") dates of Daylight Saving Time for each year in the input range.
Arguments
- years
A numeric vector specifying the range of years to evaluate. Use the format
c(start_year, end_year), e.g.,years = c(2020, 2021). Must contain at least one numeric value.- tz
A valid time zone name (default is "America/Vancouver"), used to determine DST rules. Use
OlsonNames()to see all valid options.
Value
A data frame with columns: year, spring (DST start for global north), fall (DST end for global south), spring_next_day (the second day after daylight saving changes in spring), fall_next_day (the second day after daylight saving changes in fall). If no DST transitions are found for the specified years and time zone, an empty data frame is returned with the expected column names.
Details
If years is not numeric, has zero length, <= 1907 (start year of daylight
saving changes in history) or if tz is not a recognized time zone name,
the function will throw an error. For regions without DST (e.g., Etc/UTC),
the function returns an empty data frame and issues a warning.
Examples
dst_switch_day(years = c(2020, 2021), tz = "America/Vancouver")
#> # A tibble: 2 × 5
#> year spring fall spring_next_day fall_next_day
#> <dbl> <date> <date> <date> <date>
#> 1 2020 2020-03-08 2020-11-01 2020-03-09 2020-11-02
#> 2 2021 2021-03-14 2021-11-07 2021-03-15 2021-11-08