Package org.apache.wayang.basic.operators

Class PageRankOperator

java.lang.Object

org.apache.wayang.core.plan.wayangplan.OperatorBase

org.apache.wayang.core.plan.wayangplan.UnaryToUnaryOperator<Tuple2<Long,Long>,Tuple2<Long,Float>>

org.apache.wayang.basic.operators.PageRankOperator

All Implemented Interfaces:

Serializable, ActualOperator, ElementaryOperator, Operator

Direct Known Subclasses:

FlinkPageRankOperator, GiraphPageRankOperator, JavaPageRankOperator

public class PageRankOperator
extends UnaryToUnaryOperator<Tuple2<Long,Long>,Tuple2<Long,Float>>

Operator for the PageRank algorithm. It takes as input a list of directed edges, whereby each edge is represented as (source vertex ID, target vertex ID) tuple. Its output are the page ranks, codified as (vertex ID, page rank) tuples.

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.wayang.core.plan.wayangplan.OperatorBase

OperatorBase.GsonSerializer

Field Summary

Fields

Modifier and Type	Field	Description
protected final float	dampingFactor
static final double	DEFAULT_DAMPING_FACTOR
static final ProbabilisticDoubleInterval	DEFAULT_GRAPH_DENSITIY
protected final ProbabilisticDoubleInterval	graphDensity
protected final Integer	numIterations

Fields inherited from class org.apache.wayang.core.plan.wayangplan.OperatorBase

inputSlots, outputSlots, STANDARD_OPERATOR_ARGS

Fields inherited from interface org.apache.wayang.core.plan.wayangplan.Operator

FIRST_EPOCH

Constructor Summary

Constructors

Constructor	Description
PageRankOperator(Integer numIterations)	Creates a new instance.
PageRankOperator(Integer numIterations, Double dampingFactor, ProbabilisticDoubleInterval graphDensitiy)	Creates a new instance.
PageRankOperator(PageRankOperator that)	Copies an instance (exclusive of broadcasts).

Method Summary

Modifier and Type	Method	Description
Optional<CardinalityEstimator>	createCardinalityEstimator(int outputIndex, Configuration configuration)	Provide a CardinalityEstimator for the OutputSlot at outputIndex.
float	getDampingFactor()
ProbabilisticDoubleInterval	getGraphDensity()
int	getNumIterations()

Methods inherited from class org.apache.wayang.core.plan.wayangplan.UnaryToUnaryOperator

getInput, getInputType, getOutput, getOutputType

Methods inherited from class org.apache.wayang.core.plan.wayangplan.OperatorBase

accept, addBroadcastInput, addTargetPlatform, at, collectMappedInputSlots, collectMappedOutputSlots, copy, createCopy, getAllInputs, getAllOutputs, getCardinalityEstimator, getContainer, getEpoch, getName, getOriginal, getSimpleClassName, getTargetPlatforms, isAuxiliary, isSupportingBroadcastInputs, propagateInputCardinality, propagateOutputCardinality, setAuxiliary, setCardinalityEstimator, setContainer, setEpoch, setName, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.wayang.core.plan.wayangplan.ActualOperator

accept

Methods inherited from interface org.apache.wayang.core.plan.wayangplan.ElementaryOperator

getCardinalityEstimator, isAuxiliary, setAuxiliary, setCardinalityEstimator

Methods inherited from interface org.apache.wayang.core.plan.wayangplan.Operator

addBroadcastInput, addTargetPlatform, broadcastTo, broadcastTo, collectMappedInputSlots, collectMappedOutputSlots, connectTo, connectTo, getAllInputs, getAllOutputs, getCardinalityPusher, getContainer, getEffectiveOccupant, getEffectiveOccupant, getEpoch, getEstimationContextProperties, getForwards, getInnermostLoop, getInput, getInput, getLoopStack, getName, getNumBroadcastInputs, getNumInputs, getNumOutputs, getNumRegularInputs, getOuterInputSlot, getOutermostInputSlot, getOutermostOutputSlots, getOutput, getOutput, getParent, getTargetPlatforms, isAlternative, isConversion, isElementary, isExecutionOperator, isFeedbackInput, isFeedforwardOutput, isLoopHead, isLoopSubplan, isOwnerOf, isReading, isSink, isSource, isSubplan, isSupportingBroadcastInputs, isUnconnected, propagateInputCardinality, propagateOutputCardinality, propagateOutputCardinality, replaceWith, setContainer, setEpoch, setInput, setName, setOutput

Field Details

DEFAULT_DAMPING_FACTOR

public static final double DEFAULT_DAMPING_FACTOR

See Also:

• Constant Field Values

DEFAULT_GRAPH_DENSITIY

public static final ProbabilisticDoubleInterval DEFAULT_GRAPH_DENSITIY

numIterations

protected final Integer numIterations

dampingFactor

protected final float dampingFactor

graphDensity

protected final ProbabilisticDoubleInterval graphDensity

Constructor Details

PageRankOperator

public PageRankOperator(Integer numIterations)

Creates a new instance.

Parameters:

numIterations - the number of PageRank iterations that this instance should perform

PageRankOperator

public PageRankOperator(Integer numIterations,
 Double dampingFactor,
 ProbabilisticDoubleInterval graphDensitiy)

Creates a new instance.

Parameters:

numIterations - the number of PageRank iterations that this instance should perform

PageRankOperator

public PageRankOperator(PageRankOperator that)

Copies an instance (exclusive of broadcasts).

Parameters:

that - that should be copied

Method Details

getNumIterations

public int getNumIterations()

getDampingFactor

public float getDampingFactor()

getGraphDensity

public ProbabilisticDoubleInterval getGraphDensity()

createCardinalityEstimator

public Optional<CardinalityEstimator> createCardinalityEstimator(int outputIndex,
 Configuration configuration)

Description copied from interface: ElementaryOperator

Provide a CardinalityEstimator for the OutputSlot at outputIndex.

Parameters:

outputIndex - index of the OutputSlot for that the CardinalityEstimator is requested

configuration - if the CardinalityEstimator depends on further ones, use this to obtain the latter

Returns:

an Optional that might provide the requested instance