recipes (version 0.1.0)

step_log: Logarithmic Transformation

Description

step_log creates a specification of a recipe step that will log transform data.

Usage

step_log(recipe, ..., role = NA, trained = FALSE, base = exp(1),
  columns = NULL)

Arguments

recipe

A recipe object. The step will be added to the sequence of operations for this recipe.

...

One or more selector functions to choose which variables are affected by the step. See selections for more details.

role

Not used by this step since no new variables are created.

trained

A logical to indicate if the quantities for preprocessing have been estimated.

base

A numeric value for the base.

columns

A character string of variable names that will be (eventually) populated by the terms argument.

Value

An updated version of recipe with the new step added to the sequence of existing steps (if any).

See Also

step_logit step_invlogit step_hyperbolic step_sqrt recipe prep.recipe bake.recipe

Examples

# NOT RUN {
set.seed(313)
examples <- matrix(exp(rnorm(40)), ncol = 2)
examples <- as.data.frame(examples)

rec <- recipe(~ V1 + V2, data = examples)

log_trans <- rec  %>%
  step_log(all_predictors())

log_obj <- prep(log_trans, training = examples)

transformed_te <- bake(log_obj, examples)
plot(examples$V1, transformed_te$V1)
# }