org.apache.spark.ml.feature

Class MinMaxScaler

java.lang.Object

org.apache.spark.ml.PipelineStage

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

org.apache.spark.ml.feature.MinMaxScaler

All Implemented Interfaces:

java.io.Serializable, Logging, Params, Identifiable

public class MinMaxScaler
extends Estimator<MinMaxScalerModel>

:: Experimental :: Rescale each feature individually to a common range [min, max] linearly using column summary statistics, which is also known as min-max normalization or Rescaling. The rescaled value for feature E is calculated as,

Rescaled(e_i) = \frac{e_i - E_{min}}{E_{max} - E_{min}} * (max - min) + min

For the case E_{max} == E_{min}, Rescaled(e_i) = 0.5 * (max + min) Note that since zero values will probably be transformed to non-zero values, output of the transformer will be DenseVector even for sparse input.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
MinMaxScaler()
MinMaxScaler(java.lang.String uid)

Method Summary

Methods

Modifier and Type	Method and Description
MinMaxScaler	copy(ParamMap extra) Creates a copy of this instance with the same UID and some extra params.
MinMaxScalerModel	fit(DataFrame dataset) Fits a model to the input data.
double	getMax()
double	getMin()
DoubleParam	max() upper bound after transformation, shared by all features Default: 1.0
DoubleParam	min() lower bound after transformation, shared by all features Default: 0.0
MinMaxScaler	setInputCol(java.lang.String value)
MinMaxScaler	setMax(double value)
MinMaxScaler	setMin(double value)
MinMaxScaler	setOutputCol(java.lang.String value)
StructType	transformSchema(StructType schema) :: DeveloperApi ::
java.lang.String	uid() An immutable unique ID for the object and its derivatives.
StructType	validateAndTransformSchema(StructType schema) Validates and transforms the input schema.
void	validateParams() Validates parameter values stored internally.

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

fit, fit, fit, fit

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

transformSchema

Methods inherited from class java.lang.Object

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

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.Logging

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

Constructor Detail

MinMaxScaler

public MinMaxScaler(java.lang.String uid)

MinMaxScaler

public MinMaxScaler()

Method Detail

uid

public java.lang.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 MinMaxScaler setInputCol(java.lang.String value)

setOutputCol

public MinMaxScaler setOutputCol(java.lang.String value)

setMin

public MinMaxScaler setMin(double value)

setMax

public MinMaxScaler setMax(double value)

fit

public MinMaxScalerModel fit(DataFrame dataset)

Description copied from class: Estimator

Fits a model to the input data.

Specified by:

fit in class Estimator<MinMaxScalerModel>

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)

copy

public MinMaxScaler 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.

Specified by:

copy in interface Params

Specified by:

copy in class Estimator<MinMaxScalerModel>

Parameters:

extra - (undocumented)

Returns:

(undocumented)

See Also:

defaultCopy()

min

public DoubleParam min()

lower bound after transformation, shared by all features Default: 0.0

Returns:

(undocumented)

getMin

public double getMin()

max

public DoubleParam max()

upper bound after transformation, shared by all features Default: 1.0

Returns:

(undocumented)

getMax

public double getMax()

validateAndTransformSchema

public StructType validateAndTransformSchema(StructType schema)

Validates and transforms the input schema.

validateParams

public void validateParams()

Description copied from interface: Params

Validates parameter values stored internally. Raise an exception if any parameter value is invalid.

This only needs to check for interactions between parameters. Parameter value checks which do not depend on other parameters are handled by Param.validate(). This method does not handle input/output column parameters; those are checked during schema validation.

Specified by:

validateParams in interface Params