Enum OneHotHandleUnknown 

pub enum OneHotHandleUnknown {
    Error,
    Ignore,
}

How FittedOneHotEncoder treats a category at transform time that was not seen during fit (an unknown category).

Mirrors scikit-learn’s OneHotEncoder(handle_unknown=...) parameter (sklearn/preprocessing/_encoders.py:732,750), whose _parameter_constraints accepts {'error', 'ignore', 'infrequent_if_exist'} and whose default is 'error'. ferrolearn ships Error (REQ-2) and Ignore (REQ-4); 'infrequent_if_exist' is NOT-STARTED (REQ-5).

This is a distinct type from ordinal_encoder::HandleUnknown: the one-hot encoder’s modes are {error, ignore} while the ordinal encoder’s are {error, use_encoded_value} (sklearn’s two handle_unknown enums differ the same way).

Variants

Error

Raise an error on any unknown category at transform time (scikit-learn’s default handle_unknown='error', the default here too). The unfitted encoder’s Transform::transform returns FerroError::InvalidParameter (“Found unknown categories … during transform”, _encoders.py:209-214).

Ignore

Encode an unknown category as an all-zero one-hot block for that feature, leaving every known feature untouched (scikit-learn’s handle_unknown='ignore', _encoders.py:215-240: the unknown row is masked out and no column in that feature’s block is set).

Trait Implementations

impl Clone for OneHotHandleUnknown

fn clone(&self) -> OneHotHandleUnknown

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for OneHotHandleUnknown

impl Debug for OneHotHandleUnknown

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

Formats the value using the given formatter.

impl Default for OneHotHandleUnknown

fn default() -> OneHotHandleUnknown

Returns the “default value” for a type.

impl Eq for OneHotHandleUnknown

impl PartialEq for OneHotHandleUnknown

fn eq(&self, other: &OneHotHandleUnknown) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for OneHotHandleUnknown