smile.feature

Class Nominal2Binary

java.lang.Object

smile.feature.Nominal2Binary

All Implemented Interfaces:

Feature<double[]>

public class Nominal2Binary
extends java.lang.Object
implements Feature<double[]>

Nominal variable to binary dummy variables feature generator. This is also called one-hot encoding. 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
Nominal2Binary(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	f(double[] object, int id) 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

Nominal2Binary

public Nominal2Binary(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: Feature

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

Specified by:

attributes in interface Feature<double[]>

Returns:

the variable attributes of generated features

f

public double f(double[] object,
                int id)

Description copied from interface: Feature

Generates a feature for given object.

Specified by:

f in interface Feature<double[]>

Parameters:

object - an object of interest.

id - the index of feature to be generated.

Returns:

a feature value.