polars agg for lazyframe
Performs a series of aggregations from a group-by.
Signature
> polars agg {flags} ...rest
Parameters
...rest: Expression(s) that define the aggregations to be applied
Input/output types:
| input | output |
|---|---|
| polars_dataframe | polars_dataframe |
| polars_lazyframe | polars_lazyframe |
Examples
Group by and perform an aggregation
> [[a b]; [1 2] [1 4] [2 6] [2 4]]
| polars into-lazy
| polars group-by a
| polars agg [
(polars col b | polars min | polars as "b_min")
(polars col b | polars max | polars as "b_max")
(polars col b | polars sum | polars as "b_sum")
]
| polars collect
| polars sort-by a
╭───┬───┬───────┬───────┬───────╮
│ # │ a │ b_min │ b_max │ b_sum │
├───┼───┼───────┼───────┼───────┤
│ 0 │ 1 │ 2 │ 4 │ 6 │
│ 1 │ 2 │ 4 │ 6 │ 10 │
╰───┴───┴───────┴───────┴───────╯Group by and perform an aggregation using a record
> [[a b]; [1 2] [1 4] [2 6] [2 4]]
| polars into-lazy
| polars group-by a
| polars agg {
b_min: (polars col b | polars min)
b_max: (polars col b | polars max)
b_sum: (polars col b | polars sum)
}
| polars collect
| polars sort-by a
╭───┬───┬───────┬───────┬───────╮
│ # │ a │ b_min │ b_max │ b_sum │
├───┼───┼───────┼───────┼───────┤
│ 0 │ 1 │ 2 │ 4 │ 6 │
│ 1 │ 2 │ 4 │ 6 │ 10 │
╰───┴───┴───────┴───────┴───────╯