Hill number features in a recipe — step

step_hill() is a recipes step that replaces wide species columns (one column per species, abundance or incidence values) with Hill numbers of chosen orders, so community diversity can be used as a predictor in tidymodels workflows.

Usage

step_hill(
  recipe,
  ...,
  q = c(0, 1, 2),
  prefix = "hill_q",
  keep_original_cols = FALSE,
  role = "predictor",
  trained = FALSE,
  columns = NULL,
  skip = FALSE,
  id = NULL
)

Arguments

recipe: A recipe.
...: Selectors for the species columns.
q: Orders of diversity; one output column per order, named prefix + q.
prefix: Prefix for the new columns.
keep_original_cols: Keep the species columns?
role, trained, columns, skip, id: Standard recipe step arguments.

Value

An updated recipe.

Examples

wide <- data.frame(elev = c(200, 700, 1200),
                   sp1 = c(5, 0, 2), sp2 = c(1, 3, 0), sp3 = c(2, 2, 2))
recipes::recipe(elev ~ ., data = wide) |>
  step_hill(dplyr::starts_with("sp"), q = c(0, 2)) |>
  recipes::prep() |>
  recipes::bake(new_data = NULL)
#> # A tibble: 3 x 3
#>    elev hill_q0 hill_q2
#>   <dbl>   <dbl>   <dbl>
#> 1   200       3    2.13
#> 2   700       2    1.92
#> 3  1200       2    2