org.datavec.api.transform.sequence.expansion

Class BaseSequenceExpansionTransform

java.lang.Object

org.datavec.api.transform.sequence.expansion.BaseSequenceExpansionTransform

All Implemented Interfaces:

Serializable, ColumnOp, Transform

Direct Known Subclasses:

TextToCharacterIndexTransform, TextToTermIndexSequenceTransform

public abstract class BaseSequenceExpansionTransform
extends Object
implements Transform

A base class for sequence expansion operations. The idea: for one or more columns, expand the values to multiple sequence steps; for all other columns, just duplicate the step values when expanding.

Author:

Alex Black

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected List<String>	expandedColumnNames
protected Schema	inputSchema
protected List<String>	requiredColumns

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	BaseSequenceExpansionTransform(List<String> requiredColumns, List<String> expandedColumnNames)

Method Summary

Modifier and Type	Method and Description
String	columnName() Returns a singular column name this op is meant to run on
String[]	columnNames() Returns column names this op is meant to run on
protected abstract List<ColumnMetaData>	expandedColumnMetaDatas(List<ColumnMetaData> origColumnMeta, List<String> expandedColumnNames)
protected abstract List<List<Writable>>	expandTimeStep(List<Writable> currentStepValues)
List<Writable>	map(List<Writable> writables) Transform a writable in to another writable
Object	map(Object input) Transform an object in to another object
List<List<Writable>>	mapSequence(List<List<Writable>> sequence) Transform a sequence
Object	mapSequence(Object sequence) Transform a sequence
String	outputColumnName() The output column name after the operation has been applied
String[]	outputColumnNames() The output column names This will often be the same as the input
Schema	transform(Schema inputSchema) Get the output schema for this transformation, given an input schema

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.datavec.api.transform.ColumnOp

getInputSchema, setInputSchema

Field Detail

requiredColumns

protected List<String> requiredColumns

expandedColumnNames

protected List<String> expandedColumnNames

inputSchema

protected Schema inputSchema

Constructor Detail

BaseSequenceExpansionTransform

protected BaseSequenceExpansionTransform(@NonNull
                                         List<String> requiredColumns,
                                         @NonNull
                                         List<String> expandedColumnNames)

Parameters:

requiredColumns - Input columns, to be expanded

expandedColumnNames - Names of the columns after expansion

Method Detail

expandedColumnMetaDatas

protected abstract List<ColumnMetaData> expandedColumnMetaDatas(List<ColumnMetaData> origColumnMeta,
                                                                List<String> expandedColumnNames)

expandTimeStep

protected abstract List<List<Writable>> expandTimeStep(List<Writable> currentStepValues)

transform

public Schema transform(Schema inputSchema)

Description copied from interface: ColumnOp

Get the output schema for this transformation, given an input schema

Specified by:

transform in interface ColumnOp

outputColumnName

public String outputColumnName()

Description copied from interface: ColumnOp

The output column name after the operation has been applied

Specified by:

outputColumnName in interface ColumnOp

Returns:

the output column name

outputColumnNames

public String[] outputColumnNames()

Description copied from interface: ColumnOp

The output column names This will often be the same as the input

Specified by:

outputColumnNames in interface ColumnOp

Returns:

the output column names

columnNames

public String[] columnNames()

Description copied from interface: ColumnOp

Returns column names this op is meant to run on

Specified by:

columnNames in interface ColumnOp

Returns:

columnName

public String columnName()

Description copied from interface: ColumnOp

Returns a singular column name this op is meant to run on

Specified by:

columnName in interface ColumnOp

Returns:

map

public List<Writable> map(List<Writable> writables)

Description copied from interface: Transform

Transform a writable in to another writable

Specified by:

map in interface Transform

Parameters:

writables - the record to transform

Returns:

the transformed writable

mapSequence

public List<List<Writable>> mapSequence(List<List<Writable>> sequence)

Description copied from interface: Transform

Transform a sequence

Specified by:

mapSequence in interface Transform

map

public Object map(Object input)

Description copied from interface: Transform

Transform an object in to another object

Specified by:

map in interface Transform

Parameters:

input - the record to transform

Returns:

the transformed writable

mapSequence

public Object mapSequence(Object sequence)

Description copied from interface: Transform

Transform a sequence

Specified by:

mapSequence in interface Transform