org.apache.spark.ml.feature

Class StopWordsRemover

Object

org.apache.spark.ml.PipelineStage

org.apache.spark.ml.Transformer

org.apache.spark.ml.feature.StopWordsRemover

All Implemented Interfaces:

java.io.Serializable, org.apache.spark.internal.Logging, Params, HasInputCol, HasInputCols, HasOutputCol, HasOutputCols, DefaultParamsWritable, Identifiable, MLWritable

public class StopWordsRemover
extends Transformer
implements HasInputCol, HasOutputCol, HasInputCols, HasOutputCols, DefaultParamsWritable

A feature transformer that filters out stop words from input.

Since 3.0.0, StopWordsRemover can filter out multiple columns at once by setting the inputCols parameter. Note that when both the inputCol and inputCols parameters are set, an Exception will be thrown.

See Also:

Stop words (Wikipedia), Serialized Form

Note:

null values from input array are preserved unless adding null to stopWords explicitly.

Constructor Summary

Constructors

Constructor and Description
StopWordsRemover()
StopWordsRemover(String uid)

Method Summary

Modifier and Type	Method and Description
BooleanParam	caseSensitive() Whether to do a case sensitive comparison over the stop words.
StopWordsRemover	copy(ParamMap extra) Creates a copy of this instance with the same UID and some extra params.
boolean	getCaseSensitive()
String	getLocale()
String[]	getStopWords()
Param<String>	inputCol() Param for input column name.
StringArrayParam	inputCols() Param for input column names.
static StopWordsRemover	load(String path)
static String[]	loadDefaultStopWords(String language) Loads the default stop words for the given language.
Param<String>	locale() Locale of the input for case insensitive matching.
Param<String>	outputCol() Param for output column name.
StringArrayParam	outputCols() Param for output column names.
static MLReader<T>	read()
StopWordsRemover	setCaseSensitive(boolean value)
StopWordsRemover	setInputCol(String value)
StopWordsRemover	setInputCols(String[] value)
StopWordsRemover	setLocale(String value)
StopWordsRemover	setOutputCol(String value)
StopWordsRemover	setOutputCols(String[] value)
StopWordsRemover	setStopWords(String[] value)
StringArrayParam	stopWords() The words to be filtered out.
String	toString()
Dataset<Row>	transform(Dataset<?> dataset) Transforms the input dataset.
StructType	transformSchema(StructType schema) Check transform validity and derive the output schema from the input schema.
String	uid() An immutable unique ID for the object and its derivatives.

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

transform, transform, transform

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

params

Methods inherited from class Object

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

Methods inherited from interface org.apache.spark.ml.param.shared.HasInputCol

getInputCol

Methods inherited from interface org.apache.spark.ml.param.shared.HasOutputCol

getOutputCol

Methods inherited from interface org.apache.spark.ml.param.shared.HasInputCols

getInputCols

Methods inherited from interface org.apache.spark.ml.param.shared.HasOutputCols

getOutputCols

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

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

Methods inherited from interface org.apache.spark.ml.util.DefaultParamsWritable

write

Methods inherited from interface org.apache.spark.ml.util.MLWritable

save

Methods inherited from interface org.apache.spark.internal.Logging

$init$, initializeForcefully, initializeLogIfNecessary, initializeLogIfNecessary, initializeLogIfNecessary$default$2, initLock, isTraceEnabled, log, logDebug, logDebug, logError, logError, logInfo, logInfo, logName, logTrace, logTrace, logWarning, logWarning, org$apache$spark$internal$Logging$$log__$eq, org$apache$spark$internal$Logging$$log_, uninitialize

Constructor Detail

StopWordsRemover

public StopWordsRemover(String uid)

StopWordsRemover

public StopWordsRemover()

Method Detail

load

public static StopWordsRemover load(String path)

loadDefaultStopWords

public static String[] loadDefaultStopWords(String language)

Loads the default stop words for the given language. Supported languages: danish, dutch, english, finnish, french, german, hungarian, italian, norwegian, portuguese, russian, spanish, swedish, turkish

Parameters:

language - (undocumented)

Returns:

(undocumented)

See Also:

here

read

public static MLReader<T> read()

outputCols

public final StringArrayParam outputCols()

Description copied from interface: HasOutputCols

Param for output column names.

Specified by:

outputCols in interface HasOutputCols

Returns:

(undocumented)

inputCols

public final StringArrayParam inputCols()

Description copied from interface: HasInputCols

Param for input column names.

Specified by:

inputCols in interface HasInputCols

Returns:

(undocumented)

outputCol

public final Param<String> outputCol()

Description copied from interface: HasOutputCol

Param for output column name.

Specified by:

outputCol in interface HasOutputCol

Returns:

(undocumented)

inputCol

public final Param<String> inputCol()

Description copied from interface: HasInputCol

Param for input column name.

Specified by:

inputCol in interface HasInputCol

Returns:

(undocumented)

uid

public String uid()

Description copied from interface: Identifiable

An immutable unique ID for the object and its derivatives.

Specified by:

uid in interface Identifiable

Returns:

(undocumented)

setInputCol

public StopWordsRemover setInputCol(String value)

setOutputCol

public StopWordsRemover setOutputCol(String value)

setInputCols

public StopWordsRemover setInputCols(String[] value)

setOutputCols

public StopWordsRemover setOutputCols(String[] value)

stopWords

public StringArrayParam stopWords()

The words to be filtered out. Default: English stop words

Returns:

(undocumented)

See Also:

StopWordsRemover.loadDefaultStopWords()

setStopWords

public StopWordsRemover setStopWords(String[] value)

getStopWords

public String[] getStopWords()

caseSensitive

public BooleanParam caseSensitive()

Whether to do a case sensitive comparison over the stop words. Default: false

Returns:

(undocumented)

setCaseSensitive

public StopWordsRemover setCaseSensitive(boolean value)

getCaseSensitive

public boolean getCaseSensitive()

locale

public Param<String> locale()

Locale of the input for case insensitive matching. Ignored when caseSensitive is true. Default: the string of default locale (Locale.getDefault), or Locale.US if default locale is not in available locales in JVM.

Returns:

(undocumented)

setLocale

public StopWordsRemover setLocale(String value)

getLocale

public String getLocale()

transform

public Dataset<Row> transform(Dataset<?> dataset)

Description copied from class: Transformer

Transforms the input dataset.

Specified by:

transform in class Transformer

Parameters:

dataset - (undocumented)

Returns:

(undocumented)

transformSchema

public StructType transformSchema(StructType schema)

Description copied from class: PipelineStage

Check transform validity and derive the output schema from the input schema.

We check validity for interactions between parameters during transformSchema and raise an exception if any parameter value is invalid. Parameter value checks which do not depend on other parameters are handled by Param.validate().

Typical implementation should first conduct verification on schema change and parameter validity, including complex parameter interaction checks.

Specified by:

transformSchema in class PipelineStage

Parameters:

schema - (undocumented)

Returns:

(undocumented)

copy

public StopWordsRemover copy(ParamMap extra)

Description copied from interface: Params

Creates a copy of this instance with the same UID and some extra params. Subclasses should implement this method and set the return type properly. See defaultCopy().

Specified by:

copy in interface Params

Specified by:

copy in class Transformer

Parameters:

extra - (undocumented)

Returns:

(undocumented)

toString

public String toString()

Specified by:

toString in interface Identifiable

Overrides:

toString in class Object