ml.dmlc.xgboost4j.java

Class Booster

java.lang.Object

ml.dmlc.xgboost4j.java.Booster

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

KryoBooster

public class Booster
extends Object
implements Serializable

Booster for xgboost, this is a model API that support interactive build of a XGBoost Model

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Booster.FeatureImportanceType Supported feature importance types WEIGHT = Number of nodes that a feature was used to determine a split GAIN = Average information gain per split for a feature COVER = Average cover per split for a feature TOTAL_GAIN = Total information gain over all splits of a feature TOTAL_COVER = Total cover over all splits of a feature

Field Summary

Fields

Modifier and Type	Field and Description
protected long	handle
protected int	version

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Booster(boolean isKryoBooster)
protected	Booster(Map<String,Object> params, DMatrix[] cacheMats, boolean isKryoBooster)

Method Summary

Modifier and Type	Method and Description
void	boost(DMatrix dtrain, float[] grad, float[] hess) update with give grad and hess
void	dispose()
String	evalSet(DMatrix[] evalMatrixs, String[] evalNames, IEvaluation eval) evaluate with given customized Evaluation class
String	evalSet(DMatrix[] evalMatrixs, String[] evalNames, IEvaluation eval, float[] metricsOut)
String	evalSet(DMatrix[] evalMatrixs, String[] evalNames, int iter) evaluate with given dmatrixs.
String	evalSet(DMatrix[] evalMatrixs, String[] evalNames, int iter, float[] metricsOut) evaluate with given dmatrixs.
protected void	finalize()
String	getAttr(String key) Get attribute from the Booster.
Map<String,String>	getAttrs() Get attributes stored in the Booster as a Map.
Map<String,Integer>	getFeatureScore(String featureMap) Get importance of each feature
Map<String,Integer>	getFeatureScore(String[] featureNames) Get importance of each feature with specified feature names.
String[]	getModelDump(String[] featureNames, boolean withStats) Get the dump of the model as a string array with specified feature names.
String[]	getModelDump(String[] featureNames, boolean withStats, String format)
String[]	getModelDump(String featureMap, boolean withStats) Get the dump of the model as a string array
String[]	getModelDump(String featureMap, boolean withStats, String format)
Map<String,Double>	getScore(String[] featureNames, String importanceType) Get the feature importances for gain or cover (average or total)
Map<String,Double>	getScore(String featureMap, String importanceType) Get the feature importances for gain or cover (average or total), with feature names
int	getVersion()
protected void	init(DMatrix[] cacheMats) Internal initialization function.
protected void	initFromBytes(byte[] bytes)
float[][]	predict(DMatrix data) Predict with data
float[][]	predict(DMatrix data, boolean outputMargin) Predict with data
float[][]	predict(DMatrix data, boolean outputMargin, int treeLimit) Advanced predict function with all the options.
float[][]	predictContrib(DMatrix data, int treeLimit) Output feature contributions toward predictions of given data
float[][]	predictLeaf(DMatrix data, int treeLimit) Predict leaf indices given the data
void	saveModel(OutputStream out) Save the model to file opened as output stream.
void	saveModel(String modelPath) Save model to modelPath
void	setAttr(String key, String value) Set attribute to the Booster.
void	setAttrs(Map<String,String> attrs) Set attributes to the Booster.
void	setParam(String key, Object value) Set parameter to the Booster.
void	setParams(Map<String,Object> params) Set parameters to the Booster.
void	setVersion(int version)
byte[]	toByteArray()
void	update(DMatrix dtrain, int iter) Update the booster for one iteration.
void	update(DMatrix dtrain, IObjective obj) Update with customize obj func

Methods inherited from class java.lang.Object

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

Field Detail

handle

protected long handle

version

protected int version

Constructor Detail

Booster

protected Booster(Map<String,Object> params,
                  DMatrix[] cacheMats,
                  boolean isKryoBooster)
           throws XGBoostError

Throws:

XGBoostError

Booster

protected Booster(boolean isKryoBooster)

Method Detail

setParam

public final void setParam(String key,
                           Object value)
                    throws XGBoostError

Set parameter to the Booster.

Parameters:

key - param name

value - param value

Throws:

XGBoostError - native error

setParams

public void setParams(Map<String,Object> params)
               throws XGBoostError

Set parameters to the Booster.

Parameters:

params - parameters key-value map

Throws:

XGBoostError - native error

getAttrs

public final Map<String,String> getAttrs()
                                  throws XGBoostError

Get attributes stored in the Booster as a Map.

Returns:

A map contain attribute pairs.

Throws:

XGBoostError - native error

getAttr

public final String getAttr(String key)
                     throws XGBoostError

Get attribute from the Booster.

Parameters:

key - attribute key

Returns:

attribute value

Throws:

XGBoostError - native error

setAttr

public final void setAttr(String key,
                          String value)
                   throws XGBoostError

Set attribute to the Booster.

Parameters:

key - attribute key

value - attribute value

Throws:

XGBoostError - native error

setAttrs

public void setAttrs(Map<String,String> attrs)
              throws XGBoostError

Set attributes to the Booster.

Parameters:

attrs - attributes key-value map

Throws:

XGBoostError - native error

update

public void update(DMatrix dtrain,
                   int iter)
            throws XGBoostError

Update the booster for one iteration.

Parameters:

dtrain - training data

iter - current iteration number

Throws:

XGBoostError - native error

update

public void update(DMatrix dtrain,
                   IObjective obj)
            throws XGBoostError

Update with customize obj func

Parameters:

dtrain - training data

obj - customized objective class

Throws:

XGBoostError - native error

boost

public void boost(DMatrix dtrain,
                  float[] grad,
                  float[] hess)
           throws XGBoostError

update with give grad and hess

Parameters:

dtrain - training data

grad - first order of gradient

hess - seconde order of gradient

Throws:

XGBoostError - native error

evalSet

public String evalSet(DMatrix[] evalMatrixs,
                      String[] evalNames,
                      int iter)
               throws XGBoostError

evaluate with given dmatrixs.

Parameters:

evalMatrixs - dmatrixs for evaluation

evalNames - name for eval dmatrixs, used for check results

iter - current eval iteration

Returns:

eval information

Throws:

XGBoostError - native error

evalSet

public String evalSet(DMatrix[] evalMatrixs,
                      String[] evalNames,
                      int iter,
                      float[] metricsOut)
               throws XGBoostError

evaluate with given dmatrixs.

Parameters:

evalMatrixs - dmatrixs for evaluation

evalNames - name for eval dmatrixs, used for check results

iter - current eval iteration

metricsOut - output array containing the evaluation metrics for each evalMatrix

Returns:

eval information

Throws:

XGBoostError - native error

evalSet

public String evalSet(DMatrix[] evalMatrixs,
                      String[] evalNames,
                      IEvaluation eval)
               throws XGBoostError

evaluate with given customized Evaluation class

Parameters:

evalMatrixs - evaluation matrix

evalNames - evaluation names

eval - custom evaluator

Returns:

eval information

Throws:

XGBoostError - native error

evalSet

public String evalSet(DMatrix[] evalMatrixs,
                      String[] evalNames,
                      IEvaluation eval,
                      float[] metricsOut)
               throws XGBoostError

Throws:

XGBoostError

predictLeaf

public float[][] predictLeaf(DMatrix data,
                             int treeLimit)
                      throws XGBoostError

Predict leaf indices given the data

Parameters:

data - The input data.

treeLimit - Number of trees to include, 0 means all trees.

Returns:

The leaf indices of the instance.

Throws:

XGBoostError

predictContrib

public float[][] predictContrib(DMatrix data,
                                int treeLimit)
                         throws XGBoostError

Output feature contributions toward predictions of given data

Parameters:

data - The input data.

treeLimit - Number of trees to include, 0 means all trees.

Returns:

The feature contributions and bias.

Throws:

XGBoostError

predict

public float[][] predict(DMatrix data)
                  throws XGBoostError

Predict with data

Parameters:

data - dmatrix storing the input

Returns:

predict result

Throws:

XGBoostError - native error

predict

public float[][] predict(DMatrix data,
                         boolean outputMargin)
                  throws XGBoostError

Predict with data

Parameters:

data - data

outputMargin - output margin

Returns:

predict results

Throws:

XGBoostError

predict

public float[][] predict(DMatrix data,
                         boolean outputMargin,
                         int treeLimit)
                  throws XGBoostError

Advanced predict function with all the options.

Parameters:

data - data

outputMargin - output margin

treeLimit - limit number of trees, 0 means all trees.

Returns:

predict results

Throws:

XGBoostError

saveModel

public void saveModel(String modelPath)
               throws XGBoostError

Save model to modelPath

Parameters:

modelPath - model path

Throws:

XGBoostError

saveModel

public void saveModel(OutputStream out)
               throws XGBoostError,
                      IOException

Save the model to file opened as output stream. The model format is compatible with other xgboost bindings. The output stream can only save one xgboost model. This function will close the OutputStream after the save.

Parameters:

out - The output stream

Throws:

XGBoostError

IOException

getModelDump

public String[] getModelDump(String featureMap,
                             boolean withStats)
                      throws XGBoostError

Get the dump of the model as a string array

Parameters:

withStats - Controls whether the split statistics are output.

Returns:

dumped model information

Throws:

XGBoostError - native error

getModelDump

public String[] getModelDump(String featureMap,
                             boolean withStats,
                             String format)
                      throws XGBoostError

Throws:

XGBoostError

getModelDump

public String[] getModelDump(String[] featureNames,
                             boolean withStats)
                      throws XGBoostError

Get the dump of the model as a string array with specified feature names.

Parameters:

featureNames - Names of the features.

Returns:

dumped model information

Throws:

XGBoostError

getModelDump

public String[] getModelDump(String[] featureNames,
                             boolean withStats,
                             String format)
                      throws XGBoostError

Throws:

XGBoostError

getFeatureScore

public Map<String,Integer> getFeatureScore(String[] featureNames)
                                    throws XGBoostError

Get importance of each feature with specified feature names.

Returns:

featureScoreMap key: feature name, value: feature importance score, can be nill.

Throws:

XGBoostError - native error

getFeatureScore

public Map<String,Integer> getFeatureScore(String featureMap)
                                    throws XGBoostError

Get importance of each feature

Returns:

featureScoreMap key: feature index, value: feature importance score, can be nill

Throws:

XGBoostError - native error

getScore

public Map<String,Double> getScore(String[] featureNames,
                                   String importanceType)
                            throws XGBoostError

Get the feature importances for gain or cover (average or total)

Returns:

featureImportanceMap key: feature index, values: feature importance score based on gain or cover

Throws:

XGBoostError - native error

getScore

public Map<String,Double> getScore(String featureMap,
                                   String importanceType)
                            throws XGBoostError

Get the feature importances for gain or cover (average or total), with feature names

Returns:

featureImportanceMap key: feature name, values: feature importance score based on gain or cover

Throws:

XGBoostError - native error

getVersion

public int getVersion()

setVersion

public void setVersion(int version)

toByteArray

public byte[] toByteArray()
                   throws XGBoostError

Returns:

the saved byte array.

Throws:

XGBoostError - native error

init

protected void init(DMatrix[] cacheMats)
             throws XGBoostError

Internal initialization function.

Parameters:

cacheMats - The cached DMatrix.

Throws:

XGBoostError

initFromBytes

protected void initFromBytes(byte[] bytes)
                      throws XGBoostError

Throws:

XGBoostError

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable

dispose

public void dispose()