org.apache.spark.ml.feature

Class OneHotEncoder

Object

org.apache.spark.ml.PipelineStage

org.apache.spark.ml.Transformer

org.apache.spark.ml.feature.OneHotEncoder

All Implemented Interfaces:

java.io.Serializable, Logging, Params, HasInputCol, HasOutputCol, DefaultParamsWritable, Identifiable, MLWritable

Deprecated.

OneHotEncoderEstimator will be renamed OneHotEncoder and this OneHotEncoder will be removed in 3.0.0.

public class OneHotEncoder
extends Transformer
implements HasInputCol, HasOutputCol, DefaultParamsWritable

A one-hot encoder that maps a column of category indices to a column of binary vectors, with at most a single one-value per row that indicates the input category index. For example with 5 categories, an input value of 2.0 would map to an output vector of [0.0, 0.0, 1.0, 0.0]. The last category is not included by default (configurable via OneHotEncoder!.dropLast because it makes the vector entries sum up to one, and hence linearly dependent. So an input value of 4.0 maps to [0.0, 0.0, 0.0, 0.0].

See Also:

StringIndexer for converting categorical values into category indices, Serialized Form

Note:

This is different from scikit-learn's OneHotEncoder, which keeps all categories. The output vectors are sparse.

Constructor Summary

Constructors

Constructor and Description
OneHotEncoder() Deprecated.
OneHotEncoder(String uid) Deprecated.

Method Summary

Modifier and Type	Method and Description
OneHotEncoder	copy(ParamMap extra) Deprecated. Creates a copy of this instance with the same UID and some extra params.
BooleanParam	dropLast() Deprecated. Whether to drop the last category in the encoded vector (default: true)
boolean	getDropLast() Deprecated.
static OneHotEncoder	load(String path) Deprecated.
static MLReader<T>	read() Deprecated.
OneHotEncoder	setDropLast(boolean value) Deprecated.
OneHotEncoder	setInputCol(String value) Deprecated.
OneHotEncoder	setOutputCol(String value) Deprecated.
Dataset<Row>	transform(Dataset<?> dataset) Deprecated. Transforms the input dataset.
StructType	transformSchema(StructType schema) Deprecated. :: DeveloperApi ::
String	uid() Deprecated. 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 Object

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

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

getInputCol, inputCol

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

getOutputCol, outputCol

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.Identifiable

toString

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

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

Constructor Detail

OneHotEncoder

public OneHotEncoder(String uid)

Deprecated.

OneHotEncoder

public OneHotEncoder()

Deprecated.

Method Detail

load

public static OneHotEncoder load(String path)

Deprecated.

read

public static MLReader<T> read()

Deprecated.

uid

public String uid()

Deprecated.

Description copied from interface: Identifiable

An immutable unique ID for the object and its derivatives.

Specified by:

uid in interface Identifiable

Returns:

(undocumented)

dropLast

public final BooleanParam dropLast()

Deprecated.

Whether to drop the last category in the encoded vector (default: true)

Returns:

(undocumented)

getDropLast

public boolean getDropLast()

Deprecated.

setDropLast

public OneHotEncoder setDropLast(boolean value)

Deprecated.

setInputCol

public OneHotEncoder setInputCol(String value)

Deprecated.

setOutputCol

public OneHotEncoder setOutputCol(String value)

Deprecated.

transformSchema

public StructType transformSchema(StructType schema)

Deprecated.

Description copied from class: PipelineStage

:: DeveloperApi ::

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)

transform

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

Deprecated.

Description copied from class: Transformer

Transforms the input dataset.

Specified by:

transform in class Transformer

Parameters:

dataset - (undocumented)

Returns:

(undocumented)

copy

public OneHotEncoder copy(ParamMap extra)

Deprecated.

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)