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Python API for XGBoost-Spark

This doc focuses on GPU related Python API interfaces. 7 new classes are introduced:

CrossValidator

The full name is ml.dmlc.xgboost4j.scala.spark.rapids.CrossValidator, and it is a wrapper around Scala CrossValidator.

Constructors
  • CrossValidator()
Methods

Note: Only GPU related methods are listed below.

  • fit(dataset): This method triggers the corss validation for hyperparameter tuninng.
    • dataset: a GpuDataset used for cross validation
    • returns the best Model[_] for the given hyperparameters.
    • Note: For CPU version, you can still call fit by passing a Dataset.

GpuDataset

The full name is ml.dmlc.xgboost4j.scala.spark.rapids.GpuDataset. A GpuDataset is an object that is produced by GpuDataReaders and consumed by XGBoostClassifiers and XGBoostRegressors. No constructors or methods are exposed for this class.

GpuDataReader

The full name is ml.dmlc.xgboost4j.scala.spark.rapids.GpuDataReader. A GpuDataReader sets options and builds GpuDataset from data sources. The data loading is a lazy operation. It occurs when the data is processed later.

Constructors
  • GpuDataReader(spark_session)
Methods
  • format(source): This method sets data format. Valid values include csv, parquet and orc.
    • source: a String represents the data format to set
    • returns the data reader itself
  • schema(schema): This method sets data schema.
    • schema: data schema either in StructType format or a DDL-formatted String (e.g., a INT, b STRING, c DOUBLE)
    • returns the data reader itself
  • option(key, value): This method sets an option.
    • key: a String represents the option key
    • value: the option value, valid types include Boolean, Integer, Float and String
    • returns the data reader itself
  • options(options). This method sets options.
    • options: an option Dictionary[String, String]
    • returns the data reader itself
  • load(*paths): This method builds a GpuDataset.
    • paths: the data source paths, might be empty, one path, or a list of paths
    • returns a GpuDataset as the result
  • csv(*paths): This method builds a GpuDataset.
    • paths: the CSV data paths, might be one path or a list of paths
    • returns a GpuDataset as the result
  • parquet(*paths): This method builds a GpuDataset.
    • paths: the Parquet data paths, might be one path or a list of paths
    • returns a GpuDataset as the result
  • orc(*paths):. This method builds a GpuDataset.
    • paths: the ORC data paths, might be one path or a list of paths
    • returns a GpuDataset as the result
Options
  • Common options
    • asFloats: A Boolean flag indicates whether cast all numeric values to floats. Default is True.
    • maxRowsPerChunk: An Integer specifies the max rows per chunk. Default is 2147483647 (2^31-1).
  • Options for CSV
    • comment: A single character used for skipping lines beginning with this character. Default is empty string. By default, it is disabled.
    • header: A Boolean flag indicates whether the first line should be used as names of columns. Default is False.
    • nullValue: The string representation of a null(None) value. Default is empty string.
    • quote: A single character used for escaping quoted values where the separator can be part of the value. Default is ".
    • sep: A single character as a separator between adjacent values. Default is ,.

XGBoostClassifier

The full name is ml.dmlc.xgboost4j.scala.spark.XGBoostClassifier. It is a wrapper around Scala XGBoostClassifier.

Constructors
  • XGBoostClassifier(**params)
    • all standard xgboost parameters are supported, but please note a few differences:
      • only camelCase is supported when specifying parameter names, e.g., maxDepth
      • parameter lambda is renamed to lambda_, because lambda is a keyword in Python
Methods

Note: Only GPU related methods are listed below.

  • setFeaturesCols(features_cols). This method sets the feature columns for training.
    • features_cols: a list of feature column names in String format to set
    • returns the classifier itself
  • setEvalSets(eval_sets): This method sets eval sets for training.
    • eval_sets: eval sets of type Dictionary[String, GpuDataset] for training (For CPU training, the type is Dictionary[String, DataFrame])
    • returns the classifier itself
  • fit(dataset): This method triggers the training.

XGBoostClassificationModel

The full name is ml.dmlc.xgboost4j.scala.spark.XGBoostClassificationModel. It is a wrapper around Scala XGBoostClassificationModel.

Methods

Note: Only GPU related methods are listed below.

  • transform(dataset:): This method predicts results based on the model.

XGBoostRegressor

The full name is ml.dmlc.xgboost4j.scala.spark.XGBoostRegressor. It is a wrapper around Scala XGBoostRegressor.

Constructors
  • XGBoostRegressor(**params)
    • all standard xgboost parameters are supported, but please note a few differences:
      • only camelCase is supported when specifying parameter names, e.g., maxDepth
      • parameter lambda is renamed to lambda_, because lambda is a keyword in Python
Methods

Note: Only GPU related methods are listed below.

  • setFeaturesCols(features_cols). This method sets the feature columns for training.
    • features_cols: a list of feature column names in String format to set
    • returns the regressor itself
  • setEvalSets(eval_sets): This method sets eval sets for training.
    • eval_sets: eval sets of type Dictionary[String, GpuDataset] for training (For CPU training, the type is Dictionary[String, DataFrame])
    • returns the regressor itself
  • fit(dataset): This method triggers the training.

XGBoostRegressionModel

The full name is ml.dmlc.xgboost4j.scala.spark.XGBoostRegressionModel. It is a wrapper around Scala XGBoostRegressionModel.

Methods

Note: Only GPU related methods are listed below.

  • transform(dataset:): This method predicts results based on the model.