org.apache.ignite.ml.preprocessing.encoding.onehotencoder

Class OneHotEncoderPreprocessor<K,V>

java.lang.Object

org.apache.ignite.ml.preprocessing.encoding.EncoderPreprocessor<K,V>

org.apache.ignite.ml.preprocessing.encoding.onehotencoder.OneHotEncoderPreprocessor<K,V>

Type Parameters:

K - Type of a key in upstream data.

V - Type of a value in upstream data.

All Implemented Interfaces:

Serializable, BiFunction<K,V,LabeledVector>, DeployableObject, IgniteBiFunction<K,V,LabeledVector>, Preprocessor<K,V>

public final class OneHotEncoderPreprocessor<K,V>
extends EncoderPreprocessor<K,V>
implements DeployableObject

Preprocessing function that makes one-hot encoding. One-hot encoding maps a categorical feature, represented as a label index (Double or String value), to a binary vector with at most a single one-value indicating the presence of a specific feature value from among the set of all feature values. This preprocessor can transform multiple columns which indices are handled during training process. Each one-hot encoded binary vector adds its cells to the end of the current feature vector according the order of handled categorial features.

See Also:

This prerpocessor always creates separate column for the NULL values. NOTE: the index value associated with NULL will located in binary vector according the frequency of NULL values., Serialized Form

Field Summary

Fields inherited from class org.apache.ignite.ml.preprocessing.encoding.EncoderPreprocessor

basePreprocessor, encodingValues, handledIndices, KEY_FOR_NULL_VALUES

Constructor Summary

Constructors

Constructor and Description
OneHotEncoderPreprocessor(Map<String,Integer>[] encodingValues, Preprocessor<K,V> basePreprocessor, Set<Integer> handledIndices) Constructs a new instance of One Hot Encoder preprocessor.

Method Summary

Modifier and Type	Method and Description
LabeledVector	apply(K k, V v) Applies this preprocessor.
List<Object>	getDependencies() Returns dependencies of this object that can be object with class defined by client side and unknown for server.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.ignite.ml.preprocessing.Preprocessor

map

Methods inherited from interface org.apache.ignite.ml.math.functions.IgniteBiFunction

andThen

Methods inherited from interface java.util.function.BiFunction

andThen

Constructor Detail

OneHotEncoderPreprocessor

public OneHotEncoderPreprocessor(Map<String,Integer>[] encodingValues,
                                 Preprocessor<K,V> basePreprocessor,
                                 Set<Integer> handledIndices)

Constructs a new instance of One Hot Encoder preprocessor.

Parameters:

basePreprocessor - Base preprocessor.

handledIndices - Handled indices.

Method Detail

apply

public LabeledVector apply(K k,
                           V v)

Applies this preprocessor.

Specified by:

apply in interface BiFunction<K,V,LabeledVector>

Parameters:

k - Key.

v - Value.

Returns:

Preprocessed row.

getDependencies

public List<Object> getDependencies()

Returns dependencies of this object that can be object with class defined by client side and unknown for server.

Specified by:

getDependencies in interface DeployableObject