Struct OrdinalEncoder 

pub struct OrdinalEncoder { /* private fields */ }

Encode categorical features as ordinal integers (0, 1, 2, …), mirroring sklearn.preprocessing.OrdinalEncoder.

Input is a 2-D StrMatrix; output is a numeric Matrix of the same shape, where each cell is replaced by the ordinal index of its category.

Categories per column are sorted lexicographically by default (sklearn default), or can be user-specified via OrdinalCategories::Manual.

Implementations

impl OrdinalEncoder

pub fn new(categories: OrdinalCategories) -> Self

Creates a new ordinal encoder with the given category config.

pub fn handle_unknown(self, h: OrdinalHandleUnknown) -> Self

Sets how unknown categories are handled during transform.

pub fn categories(&self) -> &[Vec<String>]

Returns the learned categories per column.

pub fn fit(&mut self, x: &StrMatrix) -> Result<()>

Learns the category-to-index mapping per column.

pub fn transform(&self, x: &StrMatrix) -> Result<Matrix>

Encodes the input as ordinal integer codes.

pub fn fit_transform(&mut self, x: &StrMatrix) -> Result<Matrix>

Fits the encoder and transforms the input in one step.

pub fn inverse_transform(&self, y: &Matrix) -> Result<StrMatrix>

Decodes ordinal integer codes back to category strings.

Trait Implementations

impl CategoricalTransformer for OrdinalEncoder

fn name(&self) -> &'static str

Human-readable name of the transformer.

fn fit(&mut self, x: &StrMatrix) -> Result<()>

Fit the transformer on categorical training data.

fn transform(&self, x: &StrMatrix) -> Result<Matrix>

Transform categorical data using fitted parameters, returning a numeric Matrix.

fn inverse_transform(&self, y: &Matrix) -> Result<StrMatrix>

Reverse the transformation, recovering category strings from numeric codes. Not all encoders support this; the default implementation returns an error.

fn is_fitted(&self) -> bool

Whether the transformer has been fitted.

fn fit_transform(&mut self, x: &StrMatrix) -> Result<Matrix>

Convenience: fit then transform.

impl Clone for OrdinalEncoder

fn clone(&self) -> OrdinalEncoder

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for OrdinalEncoder

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for OrdinalEncoder

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for OrdinalEncoder

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Estimator for OrdinalEncoder

impl FeatureNames for OrdinalEncoder

fn feature_names_out(&self, input_features: Option<&[String]>) -> Vec<String>

Returns the output feature names given the optional input feature names.

impl Serialize for OrdinalEncoder

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.