# recipes

## Introduction

With recipes, you can use [dplyr](https://dplyr.tidyverse.org/)-like
pipeable sequences of feature engineering steps to get your data ready
for modeling. For example, to create a recipe containing an outcome plus
two numeric predictors and then center and scale (“normalize”) the
predictors:

``` r

library(recipes)
data(ad_data, package = "modeldata")

ad_rec <- recipe(Class ~ tau + VEGF, data = ad_data) |>
  step_normalize(all_numeric_predictors())

ad_rec
```

More information on recipes can be found at the [*Get
Started*](https://www.tidymodels.org/start/recipes/) page of
[tidymodels.org](https://www.tidymodels.org).

You may consider recipes as an alternative method for creating and
preprocessing design matrices (also known as model matrices) that can be
used for modeling or visualization. While R already has long-standing
methods for creating such matrices
(e.g. [formulas](https://rviews.rstudio.com/2017/02/01/the-r-formula-method-the-good-parts/)
and `model.matrix`), there are some [limitations to what the existing
infrastructure can
do](https://rviews.rstudio.com/2017/03/01/the-r-formula-method-the-bad-parts/).

## Installation

There are several ways to install recipes:

``` r

# The easiest way to get recipes is to install all of tidymodels:
install.packages("tidymodels")

# Alternatively, install just recipes:
install.packages("recipes")

# Or the development version from GitHub:
# install.packages("pak")
pak::pak("tidymodels/recipes")
```

## Contributing

- For questions and discussions about tidymodels packages, modeling, and
  machine learning, please [post on RStudio
  Community](https://forum.posit.co/c/ml/15).

- If you think you have encountered a bug, please [submit an
  issue](https://github.com/tidymodels/recipes/issues).

- Either way, learn how to create and share a
  [reprex](https://reprex.tidyverse.org/articles/articles/learn-reprex.html)
  (a minimal, reproducible example), to clearly communicate about your
  code.

- Check out further details on [contributing guidelines for tidymodels
  packages](https://www.tidymodels.org/contribute/) and [how to get
  help](https://www.tidymodels.org/help/).

# Package index

## Basic Functions

- [`recipes-package`](https://recipes.tidymodels.org/reference/recipes.md)
  [`recipes`](https://recipes.tidymodels.org/reference/recipes.md) :
  recipes: A package for computing and preprocessing design matrices.
- [`recipe()`](https://recipes.tidymodels.org/reference/recipe.md) :
  Create a recipe for preprocessing data
- [`formula(`*`<recipe>`*`)`](https://recipes.tidymodels.org/reference/formula.recipe.md)
  : Create a formula from a prepared recipe
- [`print(`*`<recipe>`*`)`](https://recipes.tidymodels.org/reference/print.recipe.md)
  : Print a Recipe
- [`summary(`*`<recipe>`*`)`](https://recipes.tidymodels.org/reference/summary.recipe.md)
  : Summarize a recipe
- [`prep()`](https://recipes.tidymodels.org/reference/prep.md) :
  Estimate a preprocessing recipe
- [`bake()`](https://recipes.tidymodels.org/reference/bake.md) : Apply a
  trained preprocessing recipe
- [`juice()`](https://recipes.tidymodels.org/reference/juice.md)
  **\[superseded\]** : Extract transformed training set
- [`selections`](https://recipes.tidymodels.org/reference/selections.md)
  [`selection`](https://recipes.tidymodels.org/reference/selections.md)
  : Methods for selecting variables in step functions
- [`has_role()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`has_type()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_outcomes()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_predictors()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_date()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_date_predictors()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_datetime()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_datetime_predictors()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_double()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_double_predictors()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_factor()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_factor_predictors()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_integer()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_integer_predictors()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_logical()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_logical_predictors()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_nominal()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_nominal_predictors()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_numeric()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_numeric_predictors()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_ordered()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_ordered_predictors()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_string()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_string_predictors()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_unordered()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`all_unordered_predictors()`](https://recipes.tidymodels.org/reference/has_role.md)
  [`current_info()`](https://recipes.tidymodels.org/reference/has_role.md)
  : Role Selection
- [`add_role()`](https://recipes.tidymodels.org/reference/roles.md)
  [`update_role()`](https://recipes.tidymodels.org/reference/roles.md)
  [`remove_role()`](https://recipes.tidymodels.org/reference/roles.md) :
  Manually alter roles
- [`update_role_requirements()`](https://recipes.tidymodels.org/reference/update_role_requirements.md)
  : Update role specific requirements
- [`get_case_weights()`](https://recipes.tidymodels.org/reference/case-weight-helpers.md)
  [`averages()`](https://recipes.tidymodels.org/reference/case-weight-helpers.md)
  [`medians()`](https://recipes.tidymodels.org/reference/case-weight-helpers.md)
  [`variances()`](https://recipes.tidymodels.org/reference/case-weight-helpers.md)
  [`correlations()`](https://recipes.tidymodels.org/reference/case-weight-helpers.md)
  [`covariances()`](https://recipes.tidymodels.org/reference/case-weight-helpers.md)
  [`pca_wts()`](https://recipes.tidymodels.org/reference/case-weight-helpers.md)
  [`are_weights_used()`](https://recipes.tidymodels.org/reference/case-weight-helpers.md)
  : Helpers for steps with case weights
- [`case_weights`](https://recipes.tidymodels.org/reference/case_weights.md)
  : Using case weights with recipes

## Step Functions - Imputation

- [`step_impute_bag()`](https://recipes.tidymodels.org/reference/step_impute_bag.md)
  [`imp_vars()`](https://recipes.tidymodels.org/reference/step_impute_bag.md)
  : Impute via bagged trees
- [`step_impute_knn()`](https://recipes.tidymodels.org/reference/step_impute_knn.md)
  : Impute via k-nearest neighbors
- [`step_impute_linear()`](https://recipes.tidymodels.org/reference/step_impute_linear.md)
  : Impute numeric variables via a linear model
- [`step_impute_lower()`](https://recipes.tidymodels.org/reference/step_impute_lower.md)
  : Impute numeric data below the threshold of measurement
- [`step_impute_mean()`](https://recipes.tidymodels.org/reference/step_impute_mean.md)
  : Impute numeric data using the mean
- [`step_impute_median()`](https://recipes.tidymodels.org/reference/step_impute_median.md)
  : Impute numeric data using the median
- [`step_impute_mode()`](https://recipes.tidymodels.org/reference/step_impute_mode.md)
  : Impute nominal data using the most common value
- [`step_impute_roll()`](https://recipes.tidymodels.org/reference/step_impute_roll.md)
  : Impute numeric data using a rolling window statistic
- [`step_unknown()`](https://recipes.tidymodels.org/reference/step_unknown.md)
  : Assign missing categories to "unknown"

## Step Functions - Individual Transformations

- [`step_BoxCox()`](https://recipes.tidymodels.org/reference/step_BoxCox.md)
  : Box-Cox transformation for non-negative data
- [`step_bs()`](https://recipes.tidymodels.org/reference/step_bs.md) :
  B-spline basis functions
- [`step_harmonic()`](https://recipes.tidymodels.org/reference/step_harmonic.md)
  : Add sin and cos terms for harmonic analysis
- [`step_hyperbolic()`](https://recipes.tidymodels.org/reference/step_hyperbolic.md)
  : Hyperbolic transformations
- [`step_inverse()`](https://recipes.tidymodels.org/reference/step_inverse.md)
  : Inverse transformation
- [`step_invlogit()`](https://recipes.tidymodels.org/reference/step_invlogit.md)
  : Inverse logit transformation
- [`step_log()`](https://recipes.tidymodels.org/reference/step_log.md) :
  Logarithmic transformation
- [`step_logit()`](https://recipes.tidymodels.org/reference/step_logit.md)
  : Logit transformation
- [`step_mutate()`](https://recipes.tidymodels.org/reference/step_mutate.md)
  : Add new variables using dplyr
- [`step_ns()`](https://recipes.tidymodels.org/reference/step_ns.md) :
  Natural spline basis functions
- [`step_poly()`](https://recipes.tidymodels.org/reference/step_poly.md)
  : Orthogonal polynomial basis functions
- [`step_poly_bernstein()`](https://recipes.tidymodels.org/reference/step_poly_bernstein.md)
  : Generalized bernstein polynomial basis
- [`step_relu()`](https://recipes.tidymodels.org/reference/step_relu.md)
  : Apply (smoothed) rectified linear transformation
- [`step_spline_b()`](https://recipes.tidymodels.org/reference/step_spline_b.md)
  : Basis splines
- [`step_spline_convex()`](https://recipes.tidymodels.org/reference/step_spline_convex.md)
  : Convex splines
- [`step_spline_monotone()`](https://recipes.tidymodels.org/reference/step_spline_monotone.md)
  : Monotone splines
- [`step_spline_natural()`](https://recipes.tidymodels.org/reference/step_spline_natural.md)
  : Natural splines
- [`step_spline_nonnegative()`](https://recipes.tidymodels.org/reference/step_spline_nonnegative.md)
  : Non-negative splines
- [`step_sqrt()`](https://recipes.tidymodels.org/reference/step_sqrt.md)
  : Square root transformation
- [`step_YeoJohnson()`](https://recipes.tidymodels.org/reference/step_YeoJohnson.md)
  : Yeo-Johnson transformation

## Step Functions - Discretization

- [`step_discretize()`](https://recipes.tidymodels.org/reference/step_discretize.md)
  : Discretize Numeric Variables
- [`discretize()`](https://recipes.tidymodels.org/reference/discretize.md)
  [`predict(`*`<discretize>`*`)`](https://recipes.tidymodels.org/reference/discretize.md)
  : Discretize Numeric Variables
- [`step_cut()`](https://recipes.tidymodels.org/reference/step_cut.md) :
  Cut a numeric variable into a factor

## Step Functions - Dummy Variables and Encodings

- [`step_bin2factor()`](https://recipes.tidymodels.org/reference/step_bin2factor.md)
  : Create a factors from A dummy variable
- [`step_count()`](https://recipes.tidymodels.org/reference/step_count.md)
  : Create counts of patterns using regular expressions
- [`step_dummy()`](https://recipes.tidymodels.org/reference/step_dummy.md)
  : Create traditional dummy variables
- [`step_dummy_extract()`](https://recipes.tidymodels.org/reference/step_dummy_extract.md)
  : Extract patterns from nominal data
- [`step_dummy_multi_choice()`](https://recipes.tidymodels.org/reference/step_dummy_multi_choice.md)
  : Handle levels in multiple predictors together
- [`step_factor2string()`](https://recipes.tidymodels.org/reference/step_factor2string.md)
  : Convert factors to strings
- [`step_indicate_na()`](https://recipes.tidymodels.org/reference/step_indicate_na.md)
  : Create missing data column indicators
- [`step_integer()`](https://recipes.tidymodels.org/reference/step_integer.md)
  : Convert values to predefined integers
- [`step_novel()`](https://recipes.tidymodels.org/reference/step_novel.md)
  : Simple value assignments for novel factor levels
- [`step_num2factor()`](https://recipes.tidymodels.org/reference/step_num2factor.md)
  : Convert numbers to factors
- [`step_ordinalscore()`](https://recipes.tidymodels.org/reference/step_ordinalscore.md)
  : Convert ordinal factors to numeric scores
- [`step_other()`](https://recipes.tidymodels.org/reference/step_other.md)
  : Collapse infrequent categorical levels
- [`step_percentile()`](https://recipes.tidymodels.org/reference/step_percentile.md)
  : Percentile transformation
- [`step_regex()`](https://recipes.tidymodels.org/reference/step_regex.md)
  : Detect a regular expression
- [`step_relevel()`](https://recipes.tidymodels.org/reference/step_relevel.md)
  : Relevel factors to a desired level
- [`step_string2factor()`](https://recipes.tidymodels.org/reference/step_string2factor.md)
  : Convert strings to factors
- [`step_unknown()`](https://recipes.tidymodels.org/reference/step_unknown.md)
  : Assign missing categories to "unknown"
- [`step_unorder()`](https://recipes.tidymodels.org/reference/step_unorder.md)
  : Convert ordered factors to unordered factors

## Step Functions - Date and Datetime

- [`step_date()`](https://recipes.tidymodels.org/reference/step_date.md)
  : Date feature generator
- [`step_time()`](https://recipes.tidymodels.org/reference/step_time.md)
  : Time feature generator
- [`step_holiday()`](https://recipes.tidymodels.org/reference/step_holiday.md)
  : Holiday feature generator

## Step Functions - Interactions

- [`step_interact()`](https://recipes.tidymodels.org/reference/step_interact.md)
  : Create interaction variables

## Step Functions - Normalization

- [`step_center()`](https://recipes.tidymodels.org/reference/step_center.md)
  : Centering numeric data
- [`step_normalize()`](https://recipes.tidymodels.org/reference/step_normalize.md)
  : Center and scale numeric data
- [`step_range()`](https://recipes.tidymodels.org/reference/step_range.md)
  : Scaling numeric data to a specific range
- [`step_scale()`](https://recipes.tidymodels.org/reference/step_scale.md)
  : Scaling numeric data

## Step Functions - Multivariate Transformations

- [`step_classdist()`](https://recipes.tidymodels.org/reference/step_classdist.md)
  : Distances to class centroids
- [`step_classdist_shrunken()`](https://recipes.tidymodels.org/reference/step_classdist_shrunken.md)
  : Compute shrunken centroid distances for classification models
- [`step_depth()`](https://recipes.tidymodels.org/reference/step_depth.md)
  : Data depths
- [`step_geodist()`](https://recipes.tidymodels.org/reference/step_geodist.md)
  : Distance between two locations
- [`step_ica()`](https://recipes.tidymodels.org/reference/step_ica.md) :
  ICA signal extraction
- [`step_isomap()`](https://recipes.tidymodels.org/reference/step_isomap.md)
  : Isomap embedding
- [`step_kpca()`](https://recipes.tidymodels.org/reference/step_kpca.md)
  : Kernel PCA signal extraction
- [`step_kpca_poly()`](https://recipes.tidymodels.org/reference/step_kpca_poly.md)
  : Polynomial kernel PCA signal extraction
- [`step_kpca_rbf()`](https://recipes.tidymodels.org/reference/step_kpca_rbf.md)
  : Radial basis function kernel PCA signal extraction
- [`step_mutate_at()`](https://recipes.tidymodels.org/reference/step_mutate_at.md)
  **\[superseded\]** : Mutate multiple columns using dplyr
- [`step_nnmf()`](https://recipes.tidymodels.org/reference/step_nnmf.md)
  **\[deprecated\]** : Non-negative matrix factorization signal
  extraction
- [`step_nnmf_sparse()`](https://recipes.tidymodels.org/reference/step_nnmf_sparse.md)
  : Non-negative matrix factorization signal extraction with lasso
  penalization
- [`step_pca()`](https://recipes.tidymodels.org/reference/step_pca.md) :
  PCA signal extraction
- [`step_pls()`](https://recipes.tidymodels.org/reference/step_pls.md) :
  Partial least squares feature extraction
- [`step_ratio()`](https://recipes.tidymodels.org/reference/step_ratio.md)
  [`denom_vars()`](https://recipes.tidymodels.org/reference/step_ratio.md)
  : Ratio variable creation
- [`step_spatialsign()`](https://recipes.tidymodels.org/reference/step_spatialsign.md)
  : Spatial sign preprocessing

## Step Functions - Filters

- [`step_corr()`](https://recipes.tidymodels.org/reference/step_corr.md)
  : High correlation filter
- [`step_filter_missing()`](https://recipes.tidymodels.org/reference/step_filter_missing.md)
  : Missing value column filter
- [`step_lincomb()`](https://recipes.tidymodels.org/reference/step_lincomb.md)
  : Linear combination filter
- [`step_nzv()`](https://recipes.tidymodels.org/reference/step_nzv.md) :
  Near-zero variance filter
- [`step_rm()`](https://recipes.tidymodels.org/reference/step_rm.md) :
  General variable filter
- [`step_select()`](https://recipes.tidymodels.org/reference/step_select.md)
  **\[deprecated\]** : Select variables using dplyr
- [`step_zv()`](https://recipes.tidymodels.org/reference/step_zv.md) :
  Zero variance filter

## Step Functions - Row Operations

- [`step_arrange()`](https://recipes.tidymodels.org/reference/step_arrange.md)
  : Sort rows using dplyr
- [`step_filter()`](https://recipes.tidymodels.org/reference/step_filter.md)
  : Filter rows using dplyr
- [`step_lag()`](https://recipes.tidymodels.org/reference/step_lag.md) :
  Create a lagged predictor
- [`step_naomit()`](https://recipes.tidymodels.org/reference/step_naomit.md)
  : Remove observations with missing values
- [`step_impute_roll()`](https://recipes.tidymodels.org/reference/step_impute_roll.md)
  : Impute numeric data using a rolling window statistic
- [`step_sample()`](https://recipes.tidymodels.org/reference/step_sample.md)
  : Sample rows using dplyr
- [`step_shuffle()`](https://recipes.tidymodels.org/reference/step_shuffle.md)
  : Shuffle variables
- [`step_slice()`](https://recipes.tidymodels.org/reference/step_slice.md)
  : Filter rows by position using dplyr

## Step Functions - Others

- [`step_intercept()`](https://recipes.tidymodels.org/reference/step_intercept.md)
  : Add intercept (or constant) column
- [`step_profile()`](https://recipes.tidymodels.org/reference/step_profile.md)
  : Create a profiling version of a data set
- [`step_rename()`](https://recipes.tidymodels.org/reference/step_rename.md)
  : Rename variables by name using dplyr
- [`step_rename_at()`](https://recipes.tidymodels.org/reference/step_rename_at.md)
  : Rename multiple columns using dplyr
- [`step_window()`](https://recipes.tidymodels.org/reference/step_window.md)
  : Moving window functions

## Check Functions

- [`check_class()`](https://recipes.tidymodels.org/reference/check_class.md)
  : Check variable class
- [`check_cols()`](https://recipes.tidymodels.org/reference/check_cols.md)
  : Check if all columns are present
- [`check_missing()`](https://recipes.tidymodels.org/reference/check_missing.md)
  : Check for missing values
- [`check_new_values()`](https://recipes.tidymodels.org/reference/check_new_values.md)
  : Check for new values
- [`check_range()`](https://recipes.tidymodels.org/reference/check_range.md)
  : Check range consistency

## Developer Functions

- [`developer_functions`](https://recipes.tidymodels.org/reference/developer_functions.md)
  : Developer functions for creating recipes steps
- [`add_step()`](https://recipes.tidymodels.org/reference/add_step.md)
  [`add_check()`](https://recipes.tidymodels.org/reference/add_step.md)
  : Add a New Operation to the Current Recipe
- [`detect_step()`](https://recipes.tidymodels.org/reference/detect_step.md)
  : Detect if a particular step or check is used in a recipe
- [`fully_trained()`](https://recipes.tidymodels.org/reference/fully_trained.md)
  : Check to see if a recipe is trained/prepared
- [`.get_data_types()`](https://recipes.tidymodels.org/reference/get_data_types.md)
  : Get types for use in recipes
- [`names0()`](https://recipes.tidymodels.org/reference/names0.md)
  [`dummy_names()`](https://recipes.tidymodels.org/reference/names0.md)
  [`dummy_extract_names()`](https://recipes.tidymodels.org/reference/names0.md)
  : Naming Tools
- [`prepper()`](https://recipes.tidymodels.org/reference/prepper.md) :
  Wrapper function for preparing recipes within resampling
- [`recipes_argument_select()`](https://recipes.tidymodels.org/reference/recipes_argument_select.md)
  : Evaluate a selection with tidyselect semantics for arguments
- [`recipes_eval_select()`](https://recipes.tidymodels.org/reference/recipes_eval_select.md)
  : Evaluate a selection with tidyselect semantics specific to recipes
- [`recipes_extension_check()`](https://recipes.tidymodels.org/reference/recipes_extension_check.md)
  : Checks that steps have all S3 methods
- [`recipes_ptype()`](https://recipes.tidymodels.org/reference/recipes_ptype.md)
  : Prototype of recipe object
- [`recipes_ptype_validate()`](https://recipes.tidymodels.org/reference/recipes_ptype_validate.md)
  : Validate prototype of recipe object
- [`recipes_names_predictors()`](https://recipes.tidymodels.org/reference/recipes-role-indicator.md)
  [`recipes_names_outcomes()`](https://recipes.tidymodels.org/reference/recipes-role-indicator.md)
  : Role indicators
- [`sparse_data`](https://recipes.tidymodels.org/reference/sparse_data.md)
  : Using sparse data with recipes
- [`update(`*`<step>`*`)`](https://recipes.tidymodels.org/reference/update.step.md)
  : Update a recipe step

## Tidy Methods

- [`tidy(`*`<step_BoxCox>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_YeoJohnson>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_arrange>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_bin2factor>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_bs>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_center>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<check_class>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_classdist>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_classdist_shrunken>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<check_cols>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_corr>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_count>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_cut>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_date>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_depth>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_discretize>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_dummy>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_dummy_extract>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_dummy_multi_choice>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_factor2string>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_filter>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_filter_missing>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_geodist>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_harmonic>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_holiday>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_hyperbolic>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_ica>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_impute_bag>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_impute_knn>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_impute_linear>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_impute_lower>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_impute_mean>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_impute_median>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_impute_mode>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_impute_roll>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_indicate_na>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_integer>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_interact>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_intercept>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_inverse>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_invlogit>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_isomap>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_kpca>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_kpca_poly>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_kpca_rbf>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_lag>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_lincomb>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_log>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_logit>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<check_missing>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_mutate>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_mutate_at>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_naomit>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<check_new_values>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_nnmf>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_nnmf_sparse>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_normalize>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_novel>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_ns>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_num2factor>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_nzv>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_ordinalscore>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_other>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_pca>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_percentile>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_pls>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_poly>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_poly_bernstein>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_profile>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_range>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<check_range>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_ratio>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_regex>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_relevel>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_relu>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_rename>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_rename_at>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_rm>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_sample>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_scale>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_select>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_shuffle>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_slice>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_spatialsign>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_spline_b>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_spline_convex>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_spline_monotone>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_spline_natural>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_spline_nonnegative>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_sqrt>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_string2factor>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<recipe>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<check>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_time>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_unknown>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_unorder>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_window>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  [`tidy(`*`<step_zv>`*`)`](https://recipes.tidymodels.org/reference/tidy.recipe.md)
  : Tidy the result of a recipe

# Articles

### Get started

- [Introduction to
  recipes](https://recipes.tidymodels.org/articles/recipes.md):

  Start here if this is your first time using recipes! You will learn
  about basic usage, steps, selectors, and checks.

### Learn more

- [Handling categorical
  predictors](https://recipes.tidymodels.org/articles/Dummies.md):

  This vignette describes different methods for encoding categorical
  predictors, with special attention to interaction terms and contrasts.

- [Selecting
  variables](https://recipes.tidymodels.org/articles/Selecting_Variables.md):

  You can select which variables or features should be used in recipes.
  This vignette goes over the basics of using selection functions.

- [Roles in recipes](https://recipes.tidymodels.org/articles/Roles.md):

  In recipes, roles provide a way to select variables for different
  steps.

- [On skipping
  steps](https://recipes.tidymodels.org/articles/Skipping.md):

  In recipes, steps are usually applied to both the training and testing
  sets. However, in some situations we only want to only apply a step to
  the training data and we want to skip that step on testing data.

### Practical advice

- [Ordering of
  steps](https://recipes.tidymodels.org/articles/Ordering.md):

  The order in which recipe steps are specified matters, and this
  vignette gives some general suggestions that you should consider.

### Developer

- [Custom Steps](https://www.tidymodels.org/learn/develop/recipes/):

  Write a new recipe step for data preprocessing.

- [Recipes
  Internals](https://recipes.tidymodels.org/articles/internals.md):

  Overview and explanation of recipe object internals.

- [Dev
  checklists](https://recipes.tidymodels.org/articles/checklists.md):

  These are checklists used by the tidymodels team, extension package
  authors and contributors.

### Examples

- [Subsampling for Class
  Imbalances](https://www.tidymodels.org/learn/models/sub-sampling/):

  Improve model performance in imbalanced data sets through
  undersampling or oversampling.

- [Multivariate Analysis using Partial Least
  Squares](https://www.tidymodels.org/learn/models/pls/):

  Build and fit a predictive model with more than one outcome.