Package biz.k11i.xgboost.learner

Class ObjFunction

java.lang.Object

biz.k11i.xgboost.learner.ObjFunction

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

ObjFunction.RegLossObjLogistic, ObjFunction.RegObjFunction, ObjFunction.SoftmaxMultiClassObjClassify, ObjFunction.SoftmaxMultiClassObjProb

public class ObjFunction
extends java.lang.Object
implements java.io.Serializable

Objective function implementations.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static class	ObjFunction.RegLossObjLogistic	Logistic regression.
(package private) static class	ObjFunction.RegLossObjLogistic_Jafama	Logistic regression.
(package private) static class	ObjFunction.RegObjFunction	Regression.
(package private) static class	ObjFunction.SoftmaxMultiClassObjClassify	Multiclass classification.
(package private) static class	ObjFunction.SoftmaxMultiClassObjProb	Multiclass classification (predicted probability).
(package private) static class	ObjFunction.SoftmaxMultiClassObjProb_Jafama	Multiclass classification (predicted probability).

Field Summary

Fields

Modifier and Type	Field	Description
private static java.util.Map<java.lang.String,ObjFunction>	FUNCTIONS

Constructor Summary

Constructors

Constructor	Description
ObjFunction()

Method Summary

Modifier and Type	Method	Description
static ObjFunction	fromName(java.lang.String name)	Gets ObjFunction from given name.
float	predTransform(float pred)	Transforms a prediction value.
float[]	predTransform(float[] preds)	Transforms prediction values.
float	probToMargin(float prob)
static void	register(java.lang.String name, ObjFunction objFunction)	Deprecated. This method will be made private.
static void	useFastMathExp(boolean useJafama)	Uses Jafama's FastMath.exp(double) instead of Math.exp(double).

Methods inherited from class java.lang.Object

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

Field Detail

FUNCTIONS

private static final java.util.Map<java.lang.String,ObjFunction> FUNCTIONS

Constructor Detail

ObjFunction

public ObjFunction()

Method Detail

fromName

public static ObjFunction fromName(java.lang.String name)

Gets ObjFunction from given name.

Parameters:

name - name of objective function

Returns:

objective function

register

public static void register(java.lang.String name,
                            ObjFunction objFunction)

Deprecated.

This method will be made private. Please use PredictorConfiguration.Builder.objFunction(ObjFunction) instead.

Register an ObjFunction for a given name.

Parameters:

name - name of objective function

objFunction - objective function

useFastMathExp

public static void useFastMathExp(boolean useJafama)

Uses Jafama's FastMath.exp(double) instead of Math.exp(double).

Parameters:

useJafama - true if you want to use Jafama's FastMath.exp(double), or false if you don't want to use it but JDK's Math.exp(double).

predTransform

public float[] predTransform(float[] preds)

Transforms prediction values.

Parameters:

preds - prediction

Returns:

transformed values

predTransform

public float predTransform(float pred)

Transforms a prediction value.

Parameters:

pred - prediction

Returns:

transformed value

probToMargin

public float probToMargin(float prob)