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GroupBy First

Source code

Description

Reduce the groups to the first value.

Usage

<GroupBy>$first()

Value

aggregated DataFrame

Examples

library("polars")

df = pl$DataFrame(
  a = c(1, 2, 2, 3, 4, 5),
  b = c(0.5, 0.5, 4, 10, 13, 14),
  c = c(TRUE, TRUE, TRUE, FALSE, FALSE, TRUE),
  d = c("Apple", "Orange", "Apple", "Apple", "Banana", "Banana")
)
df$group_by("d", maintain_order = TRUE)$first()
#> shape: (3, 4)
#> ┌────────┬─────┬──────┬───────┐
#> │ d      ┆ a   ┆ b    ┆ c     │
#> │ ---    ┆ --- ┆ ---  ┆ ---   │
#> │ str    ┆ f64 ┆ f64  ┆ bool  │
#> ╞════════╪═════╪══════╪═══════╡
#> │ Apple  ┆ 1.0 ┆ 0.5  ┆ true  │
#> │ Orange ┆ 2.0 ┆ 0.5  ┆ true  │
#> │ Banana ┆ 4.0 ┆ 13.0 ┆ false │
#> └────────┴─────┴──────┴───────┘