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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/string2factor.R
\name{step_string2factor}
\alias{step_string2factor}
\alias{tidy.step_string2factor}
\title{Convert Strings to Factors}
\usage{
step_string2factor(
recipe,
...,
role = NA,
trained = FALSE,
levels = NULL,
ordered = FALSE,
skip = FALSE,
id = rand_id("string2factor")
)
\method{tidy}{step_string2factor}(x, ...)
}
\arguments{
\item{recipe}{A recipe object. The step will be added to the
sequence of operations for this recipe.}
\item{...}{One or more selector functions to choose which
variables will be converted to factors. See
\code{\link[=selections]{selections()}} for more details. For the \code{tidy}
method, these are not currently used.}
\item{role}{Not used by this step since no new variables are
created.}
\item{trained}{A logical to indicate if the quantities for
preprocessing have been estimated.}
\item{levels}{An options specification of the levels to be used
for the new factor. If left \code{NULL}, the sorted unique
values present when \code{bake} is called will be used.}
\item{ordered}{A single logical value; should the factor(s) be
ordered?}
\item{skip}{A logical. Should the step be skipped when the
recipe is baked by \code{\link[=bake.recipe]{bake.recipe()}}? While all operations are baked
when \code{\link[=prep.recipe]{prep.recipe()}} is run, some operations may not be able to be
conducted on new data (e.g. processing the outcome variable(s)).
Care should be taken when using \code{skip = TRUE} as it may affect
the computations for subsequent operations}
\item{id}{A character string that is unique to this step to identify it.}
\item{x}{A \code{step_string2factor} object.}
}
\value{
An updated version of \code{recipe} with the new step
added to the sequence of existing steps (if any). For the
\code{tidy} method, a tibble with columns \code{terms} (the
selectors or variables selected) and \code{ordered}.
}
\description{
\code{step_string2factor} will convert one or more character
vectors to factors (ordered or unordered).
}
\details{
If \code{levels} is given, \code{step_string2factor} will
convert all variables affected by this step to have the same
levels.
Also, note that \code{prep} has an option \code{strings_as_factors} that
defaults to \code{TRUE}. This should be changed so that raw character
data will be applied to \code{step_string2factor}. However, this step
can also take existing factors (but will leave them as-is).
}
\examples{
library(modeldata)
data(okc)
rec <- recipe(~ diet + location, data = okc)
make_factor <- rec \%>\%
step_string2factor(diet)
make_factor <- prep(make_factor,
training = okc,
strings_as_factors = FALSE)
# note that `diet` is a factor
bake(make_factor, new_data = NULL) \%>\% head
okc \%>\% head
tidy(make_factor, number = 1)
}
\seealso{
\code{\link[=step_factor2string]{step_factor2string()}} \code{\link[=step_dummy]{step_dummy()}} \code{\link[=step_other]{step_other()}}
\code{\link[=step_novel]{step_novel()}}
}
\concept{factors}
\concept{preprocessing}
\concept{variable_encodings}
\keyword{datagen}
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