org.apache.spark.ml.feature

Class StringIndexer

Object

org.apache.spark.ml.PipelineStage

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

org.apache.spark.ml.feature.StringIndexer

All Implemented Interfaces:

java.io.Serializable, Logging, Params

public class StringIndexer
extends Estimator<StringIndexerModel>

:: Experimental :: A label indexer that maps a string column of labels to an ML column of label indices. If the input column is numeric, we cast it to string and index the string values. The indices are in [0, numLabels), ordered by label frequencies. So the most frequent label gets index 0.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
StringIndexer()
StringIndexer(String uid)

Method Summary

Methods

Modifier and Type	Method and Description
StringIndexerModel	fit(DataFrame dataset) Fits a model to the input data.
StringIndexer	setInputCol(String value)
StringIndexer	setOutputCol(String value)
StructType	transformSchema(StructType schema) :: DeveloperApi ::
String	uid()
StructType	validateAndTransformSchema(StructType schema) Validates and transforms the input schema.

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

copy, fit, 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

clear, copy, copyValues, defaultParamMap, explainParam, explainParams, extractParamMap, extractParamMap, get, getDefault, getOrDefault, getParam, hasDefault, hasParam, isDefined, isSet, paramMap, params, set, set, set, setDefault, setDefault, setDefault, shouldOwn, validateParams

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

StringIndexer

public StringIndexer(String uid)

StringIndexer

public StringIndexer()

Method Detail

uid

public String uid()

setInputCol

public StringIndexer setInputCol(String value)

setOutputCol

public StringIndexer setOutputCol(String value)

fit

public StringIndexerModel fit(DataFrame dataset)

Description copied from class: Estimator

Fits a model to the input data.

Specified by:

fit in class Estimator<StringIndexerModel>

Parameters:

dataset - (undocumented)

Returns:

(undocumented)

transformSchema

public StructType transformSchema(StructType schema)

Description copied from class: PipelineStage

:: DeveloperApi ::

Derives the output schema from the input schema.

Specified by:

transformSchema in class PipelineStage

Parameters:

schema - (undocumented)

Returns:

(undocumented)

validateAndTransformSchema

public StructType validateAndTransformSchema(StructType schema)

Validates and transforms the input schema.