Registering custom functionality with a polars Series

Description

Usage

pl_api_register_series_namespace(name, ns_fn)

Arguments

name Name under which the functionality will be accessed.

ns_fn A function returns a new environment with the custom functionality. See examples for details.

Value

NULL invisibly.

Examples

library("polars")

# s: polars series
math_shortcuts <- function(s) {
  # Create a new environment to store the methods
  self <- new.env(parent = emptyenv())

  # Store the series
  self$`_s` <- s

  # Add methods
  self$square <- function() self$`_s` * self$`_s`
  self$cube <- function() self$`_s` * self$`_s` * self$`_s`

  # Set the class
  class(self) <- c("polars_namespace_series", "polars_object")

  # Return the environment
  self
}

pl$api$register_series_namespace("math", math_shortcuts)

s <- as_polars_series(c(1.5, 31, 42, 64.5))
s$math$square()$rename("s^2")

#> shape: (4, 1)
#> ┌─────────┐
#> │ s^2     │
#> │ ---     │
#> │ f64     │
#> ╞═════════╡
#> │ 2.25    │
#> │ 961.0   │
#> │ 1764.0  │
#> │ 4160.25 │
#> └─────────┘

s <- as_polars_series(1:5)
s$math$cube()$rename("s^3")

#> shape: (5, 1)
#> ┌─────┐
#> │ s^3 │
#> │ --- │
#> │ i32 │
#> ╞═════╡
#> │ 1   │
#> │ 8   │
#> │ 27  │
#> │ 64  │
#> │ 125 │
#> └─────┘