org.deeplearning4j.graph.iterator

Class RandomWalkIterator<V>

java.lang.Object

org.deeplearning4j.graph.iterator.RandomWalkIterator<V>

All Implemented Interfaces:

GraphWalkIterator<V>

public class RandomWalkIterator<V>
extends Object
implements GraphWalkIterator<V>

Given a graph, iterate through random walks on that graph of a specified length. Random walks are generated starting at every node in the graph exactly once, though the order of the starting nodes is randomized.

Author:

Alex Black

Constructor Summary

Constructors

Constructor and Description
RandomWalkIterator(IGraph<V,?> graph, int walkLength)
RandomWalkIterator(IGraph<V,?> graph, int walkLength, long rngSeed) Construct a RandomWalkIterator for a given graph, with a specified walk length and random number generator seed. Uses NoEdgeHandling.EXCEPTION_ON_DISCONNECTED - hence exception will be thrown when generating random walks on graphs with vertices containing having no edges, or no outgoing edges (for directed graphs)
RandomWalkIterator(IGraph<V,?> graph, int walkLength, long rngSeed, NoEdgeHandling mode)
RandomWalkIterator(IGraph<V,?> graph, int walkLength, long rngSeed, NoEdgeHandling mode, int firstVertex, int lastVertex) Constructor used to generate random walks starting at a subset of the vertices in the graph.

Method Summary

Modifier and Type	Method and Description
boolean	hasNext() Whether the iterator has any more vertex sequences.
IVertexSequence<V>	next() Get the next vertex sequence.
void	reset() Reset the graph walk iterator.
int	walkLength() Length of the walks returned by next() Note that a walk of length i contains i+1 vertices

Methods inherited from class java.lang.Object

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

Constructor Detail

RandomWalkIterator

public RandomWalkIterator(IGraph<V,?> graph,
                          int walkLength)

RandomWalkIterator

public RandomWalkIterator(IGraph<V,?> graph,
                          int walkLength,
                          long rngSeed)

Construct a RandomWalkIterator for a given graph, with a specified walk length and random number generator seed.
Uses NoEdgeHandling.EXCEPTION_ON_DISCONNECTED - hence exception will be thrown when generating random walks on graphs with vertices containing having no edges, or no outgoing edges (for directed graphs)

See Also:

RandomWalkIterator(IGraph, int, long, NoEdgeHandling)

RandomWalkIterator

public RandomWalkIterator(IGraph<V,?> graph,
                          int walkLength,
                          long rngSeed,
                          NoEdgeHandling mode)

Parameters:

graph - IGraph to conduct walks on

walkLength - length of each walk. Walk of length 0 includes 1 vertex, walk of 1 includes 2 vertices etc

rngSeed - seed for randomization

mode - mode for handling random walks from vertices with either no edges, or no outgoing edges (for directed graphs)

RandomWalkIterator

public RandomWalkIterator(IGraph<V,?> graph,
                          int walkLength,
                          long rngSeed,
                          NoEdgeHandling mode,
                          int firstVertex,
                          int lastVertex)

Constructor used to generate random walks starting at a subset of the vertices in the graph. Order of starting vertices is randomized within this subset

Parameters:

graph - IGraph to conduct walks on

walkLength - length of each walk. Walk of length 0 includes 1 vertex, walk of 1 includes 2 vertices etc

rngSeed - seed for randomization

mode - mode for handling random walks from vertices with either no edges, or no outgoing edges (for directed graphs)

firstVertex - first vertex index (inclusive) to start random walks from

lastVertex - last vertex index (exclusive) to start random walks from

Method Detail

next

public IVertexSequence<V> next()

Description copied from interface: GraphWalkIterator

Get the next vertex sequence.

Specified by:

next in interface GraphWalkIterator<V>

hasNext

public boolean hasNext()

Description copied from interface: GraphWalkIterator

Whether the iterator has any more vertex sequences.

Specified by:

hasNext in interface GraphWalkIterator<V>

reset

public void reset()

Description copied from interface: GraphWalkIterator

Reset the graph walk iterator.

Specified by:

reset in interface GraphWalkIterator<V>

walkLength

public int walkLength()

Description copied from interface: GraphWalkIterator

Length of the walks returned by next() Note that a walk of length i contains i+1 vertices

Specified by:

walkLength in interface GraphWalkIterator<V>