Class XGBoost


  • public class XGBoost
    extends Object
    trainer for xgboost
    Author:
    hzx
    • Constructor Detail

      • XGBoost

        public XGBoost()
    • Method Detail

      • loadModel

        public static Booster loadModel​(String modelPath)
                                 throws XGBoostError
        load model from modelPath
        Parameters:
        modelPath - booster modelPath (model generated by booster.saveModel)
        Throws:
        XGBoostError - native error
      • loadModel

        public static Booster loadModel​(InputStream in)
                                 throws XGBoostError,
                                        IOException
        Load a new Booster model from a file opened as input stream. The assumption is the input stream only contains one XGBoost Model. This can be used to load existing booster models saved by other xgboost bindings.
        Parameters:
        in - The input stream of the file, will be closed after this function call.
        Returns:
        The create boosted
        Throws:
        XGBoostError
        IOException
      • train

        public static Booster train​(DMatrix dtrain,
                                    Map<String,​Object> params,
                                    int round,
                                    Map<String,​DMatrix> watches,
                                    IObjective obj,
                                    IEvaluation eval)
                             throws XGBoostError
        Train a booster given parameters.
        Parameters:
        dtrain - Data to be trained.
        params - Parameters.
        round - Number of boosting iterations.
        watches - a group of items to be evaluated during training, this allows user to watch performance on the validation set.
        obj - customized objective
        eval - customized evaluation
        Returns:
        The trained booster.
        Throws:
        XGBoostError
      • train

        public static Booster train​(DMatrix dtrain,
                                    Map<String,​Object> params,
                                    int round,
                                    Map<String,​DMatrix> watches,
                                    float[][] metrics,
                                    IObjective obj,
                                    IEvaluation eval,
                                    int earlyStoppingRound)
                             throws XGBoostError
        Train a booster given parameters.
        Parameters:
        dtrain - Data to be trained.
        params - Parameters.
        round - Number of boosting iterations.
        watches - a group of items to be evaluated during training, this allows user to watch performance on the validation set.
        metrics - array containing the evaluation metrics for each matrix in watches for each iteration
        earlyStoppingRound - if non-zero, training would be stopped after a specified number of consecutive increases in any evaluation metric.
        obj - customized objective
        eval - customized evaluation
        Returns:
        The trained booster.
        Throws:
        XGBoostError
      • train

        public static Booster train​(DMatrix dtrain,
                                    Map<String,​Object> params,
                                    int round,
                                    Map<String,​DMatrix> watches,
                                    float[][] metrics,
                                    IObjective obj,
                                    IEvaluation eval,
                                    int earlyStoppingRounds,
                                    Booster booster)
                             throws XGBoostError
        Train a booster given parameters.
        Parameters:
        dtrain - Data to be trained.
        params - Parameters.
        round - Number of boosting iterations.
        watches - a group of items to be evaluated during training, this allows user to watch performance on the validation set.
        metrics - array containing the evaluation metrics for each matrix in watches for each iteration
        earlyStoppingRounds - if non-zero, training would be stopped after a specified number of consecutive goes to the unexpected direction in any evaluation metric.
        obj - customized objective
        eval - customized evaluation
        booster - train from scratch if set to null; train from an existing booster if not null.
        Returns:
        The trained booster.
        Throws:
        XGBoostError
      • crossValidation

        public static String[] crossValidation​(DMatrix data,
                                               Map<String,​Object> params,
                                               int round,
                                               int nfold,
                                               String[] metrics,
                                               IObjective obj,
                                               IEvaluation eval)
                                        throws XGBoostError
        Cross-validation with given parameters.
        Parameters:
        data - Data to be trained.
        params - Booster params.
        round - Number of boosting iterations.
        nfold - Number of folds in CV.
        metrics - Evaluation metrics to be watched in CV.
        obj - customized objective (set to null if not used)
        eval - customized evaluation (set to null if not used)
        Returns:
        evaluation history
        Throws:
        XGBoostError - native error