smile.feature

Class OneHotEncoder

java.lang.Object

smile.feature.OneHotEncoder

All Implemented Interfaces:

FeatureGenerator<double[]>

public class OneHotEncoder
extends java.lang.Object
implements FeatureGenerator<double[]>

Encode categorical integer features using a one-hot aka one-of-K scheme. Although some method such as decision trees can handle nominal variable directly, other methods generally require nominal variables converted to multiple binary dummy variables to indicate the presence or absence of a characteristic.

Constructor Summary

Constructors

Constructor and Description
OneHotEncoder(smile.data.Attribute[] attributes) Constructor.

Method Summary

Modifier and Type	Method and Description
smile.data.Attribute[]	attributes() Returns the variable attributes of generated features.
double[]	feature(double[] x) Generates a feature for given object.

Methods inherited from class java.lang.Object

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

Constructor Detail

OneHotEncoder

public OneHotEncoder(smile.data.Attribute[] attributes)

Constructor.

Parameters:

attributes - the variable attributes. Of which, nominal variables will be converted to binary dummy variables.

Method Detail

attributes

public smile.data.Attribute[] attributes()

Description copied from interface: FeatureGenerator

Returns the variable attributes of generated features. Note that these are NOT the original variable attributes of objects.

Specified by:

attributes in interface FeatureGenerator<double[]>

Returns:

the variable attributes of generated features

feature

public double[] feature(double[] x)

Description copied from interface: FeatureGenerator

Generates a feature for given object.

Specified by:

feature in interface FeatureGenerator<double[]>

Parameters:

x - an object of interest.

Returns:

a feature vector.