Base offset from UTC

Description

This computes the offset between a time zone and UTC. This is usually constant for all datetimes in a given time zone, but may vary in the rare case that a country switches time zone, like Samoa (Apia) did at the end of 2011. Use $dt$dst_offset() to take daylight saving time into account.

Usage

<Expr>$dt$base_utc_offset()

Value

A polars expression

Examples

library("polars")

df <- pl$DataFrame(
  x = as.POSIXct(c("2011-12-29", "2012-01-01"), tz = "Pacific/Apia")
)
df$with_columns(base_utc_offset = pl$col("x")$dt$base_utc_offset())

#> shape: (2, 2)
#> ┌────────────────────────────┬─────────────────┐
#> │ x                          ┆ base_utc_offset │
#> │ ---                        ┆ ---             │
#> │ datetime[ms, Pacific/Apia] ┆ duration[ms]    │
#> ╞════════════════════════════╪═════════════════╡
#> │ 2011-12-29 00:00:00 -10    ┆ -11h            │
#> │ 2012-01-01 00:00:00 +14    ┆ 13h             │
#> └────────────────────────────┴─────────────────┘