org.apache.spark.ml

Class Pipeline

Object

org.apache.spark.ml.PipelineStage

org.apache.spark.ml.Estimator<PipelineModel>

org.apache.spark.ml.Pipeline

All Implemented Interfaces:

java.io.Serializable, Logging, Identifiable, Params

public class Pipeline
extends Estimator<PipelineModel>

:: AlphaComponent :: A simple pipeline, which acts as an estimator. A Pipeline consists of a sequence of stages, each of which is either an Estimator or a Transformer. When fit(org.apache.spark.sql.DataFrame, org.apache.spark.ml.param.ParamMap) is called, the stages are executed in order. If a stage is an Estimator, its Estimator.fit(org.apache.spark.sql.DataFrame, org.apache.spark.ml.param.ParamPair<?>...) method will be called on the input dataset to fit a model. Then the model, which is a transformer, will be used to transform the dataset as the input to the next stage. If a stage is a Transformer, its Transformer.transform(org.apache.spark.sql.DataFrame, org.apache.spark.ml.param.ParamPair<?>...) method will be called to produce the dataset for the next stage. The fitted model from a Pipeline is an PipelineModel, which consists of fitted models and transformers, corresponding to the pipeline stages. If there are no stages, the pipeline acts as an identity transformer.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Pipeline()

Method Summary

Methods

Modifier and Type	Method and Description
PipelineModel	fit(DataFrame dataset, ParamMap paramMap) Fits the pipeline to the input dataset with additional parameters.
PipelineStage[]	getStages()
Pipeline	setStages(PipelineStage[] value)
Param<PipelineStage[]>	stages() param for pipeline stages
StructType	transformSchema(StructType schema, ParamMap paramMap) :: DeveloperApi ::

Methods inherited from class org.apache.spark.ml.Estimator

fit, fit, fit

Methods inherited from class Object

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

Methods inherited from interface org.apache.spark.ml.param.Params

addOutputColumn, checkInputColumn, explainParams, get, getParam, isSet, paramMap, params, set, set, validate, validate

Methods inherited from interface org.apache.spark.ml.Identifiable

uid

Methods inherited from interface org.apache.spark.Logging

initializeIfNecessary, initializeLogging, isTraceEnabled, log_, log, logDebug, logDebug, logError, logError, logInfo, logInfo, logName, logTrace, logTrace, logWarning, logWarning

Constructor Detail

Pipeline

public Pipeline()

Method Detail

stages

public Param<PipelineStage[]> stages()

param for pipeline stages

setStages

public Pipeline setStages(PipelineStage[] value)

getStages

public PipelineStage[] getStages()

fit

public PipelineModel fit(DataFrame dataset,
                ParamMap paramMap)

Fits the pipeline to the input dataset with additional parameters. If a stage is an Estimator, its Estimator.fit(org.apache.spark.sql.DataFrame, org.apache.spark.ml.param.ParamPair<?>...) method will be called on the input dataset to fit a model. Then the model, which is a transformer, will be used to transform the dataset as the input to the next stage. If a stage is a Transformer, its Transformer.transform(org.apache.spark.sql.DataFrame, org.apache.spark.ml.param.ParamPair<?>...) method will be called to produce the dataset for the next stage. The fitted model from a Pipeline is an PipelineModel, which consists of fitted models and transformers, corresponding to the pipeline stages. If there are no stages, the output model acts as an identity transformer.

Specified by:

fit in class Estimator<PipelineModel>

Parameters:

dataset - input dataset

paramMap - parameter map

Returns:

fitted pipeline

transformSchema

public StructType transformSchema(StructType schema,
                         ParamMap paramMap)

Description copied from class: PipelineStage

:: DeveloperApi ::

Derives the output schema from the input schema and parameters. The schema describes the columns and types of the data.

Specified by:

transformSchema in class PipelineStage

Parameters:

schema - Input schema to this stage

paramMap - Parameters passed to this stage

Returns:

Output schema from this stage