Fill null values using the specified value or strategy

Description

Usage

<LazyFrame>$fill_null(
  value,
  strategy = NULL,
  limit = NULL,
  ...,
  matches_supertype = TRUE
)

Arguments

value Value used to fill null values.

strategy Strategy used to fill null values. Must be one of: “forward”, “backward”, “min”, “max”, “mean”, “zero”, “one”, or NULL (default).

limit Number of consecutive null values to fill when using the “forward” or “backward” strategy.

… These dots are for future extensions and must be empty.

matches_supertype Fill all matching supertypes of the fill value literal.

Value

A polars LazyFrame

Examples

library("polars")

lf <- pl$LazyFrame(
  a = c(1.5, 2, NA, 4),
  b = c(1.5, NA, NA, 4)
)
lf$fill_null(99)$collect()

#> shape: (4, 2)
#> ┌──────┬──────┐
#> │ a    ┆ b    │
#> │ ---  ┆ ---  │
#> │ f64  ┆ f64  │
#> ╞══════╪══════╡
#> │ 1.5  ┆ 1.5  │
#> │ 2.0  ┆ 99.0 │
#> │ 99.0 ┆ 99.0 │
#> │ 4.0  ┆ 4.0  │
#> └──────┴──────┘

lf$fill_null(strategy = "forward")$collect()

#> shape: (4, 2)
#> ┌─────┬─────┐
#> │ a   ┆ b   │
#> │ --- ┆ --- │
#> │ f64 ┆ f64 │
#> ╞═════╪═════╡
#> │ 1.5 ┆ 1.5 │
#> │ 2.0 ┆ 1.5 │
#> │ 2.0 ┆ 1.5 │
#> │ 4.0 ┆ 4.0 │
#> └─────┴─────┘

lf$fill_null(strategy = "max")$collect()

#> shape: (4, 2)
#> ┌─────┬─────┐
#> │ a   ┆ b   │
#> │ --- ┆ --- │
#> │ f64 ┆ f64 │
#> ╞═════╪═════╡
#> │ 1.5 ┆ 1.5 │
#> │ 2.0 ┆ 4.0 │
#> │ 4.0 ┆ 4.0 │
#> │ 4.0 ┆ 4.0 │
#> └─────┴─────┘

lf$fill_null(strategy = "zero")$collect()

#> shape: (4, 2)
#> ┌─────┬─────┐
#> │ a   ┆ b   │
#> │ --- ┆ --- │
#> │ f64 ┆ f64 │
#> ╞═════╪═════╡
#> │ 1.5 ┆ 1.5 │
#> │ 2.0 ┆ 0.0 │
#> │ 0.0 ┆ 0.0 │
#> │ 4.0 ┆ 4.0 │
#> └─────┴─────┘