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Aggregate over a GroupBy

Source code

Description

Aggregate a DataFrame over a groupby

Usage

<GroupBy>$agg(...)

Arguments

… exprs to aggregate over. … args can also be passed wrapped in a list $agg(list(e1,e2,e3))

Value

aggregated DataFrame

Examples

library("polars")

pl$DataFrame(
  foo = c("one", "two", "two", "one", "two"),
  bar = c(5, 3, 2, 4, 1)
)$group_by("foo")$agg(
  pl$col("bar")$sum()$name$suffix("_sum"),
  pl$col("bar")$mean()$alias("bar_tail_sum")
)

#> shape: (2, 3)
#> ┌─────┬─────────┬──────────────┐
#> │ foo ┆ bar_sum ┆ bar_tail_sum │
#> │ --- ┆ ---     ┆ ---          │
#> │ str ┆ f64     ┆ f64          │
#> ╞═════╪═════════╪══════════════╡
#> │ two ┆ 6.0     ┆ 2.0          │
#> │ one ┆ 9.0     ┆ 4.5          │
#> └─────┴─────────┴──────────────┘