slib.graph.algo.extraction.rvf

Class RVF_DAG

java.lang.Object

slib.graph.algo.extraction.rvf.RVF

slib.graph.algo.extraction.rvf.RVF_DAG

Direct Known Subclasses:

RVF_TAX

public class RVF_DAG
extends RVF

Object of this class can be used to retrieve the vertices reachable from a particular vertex of an acyclic graph considering particular relationships i.e. EdgeTypes

Author:

Sébastien Harispe

Field Summary

Fields inherited from class slib.graph.algo.extraction.rvf.RVF

g, wc

Constructor Summary

Constructors

Constructor and Description
RVF_DAG(G g, WalkConstraint wc) Create a basic RVF object considering an acyclic graph and a only one type of relationships to consider during the traversal.

Method Summary

Methods

Modifier and Type	Method and Description
Map<org.openrdf.model.URI,Integer>	computeNbPathLeadingToAllVertices()
Map<org.openrdf.model.URI,Set<org.openrdf.model.URI>>	getAllRV() Compute the set of reachable vertices for each vertices contained in the graph according to the specified constraint associated to the instance in use.
Map<org.openrdf.model.URI,Set<org.openrdf.model.URI>>	getTerminalVertices() Return the set of terminal vertices (leaves) reachable.
Map<org.openrdf.model.URI,Integer>	propagateNbOccurences(Map<org.openrdf.model.URI,Integer> nbOccurrence) Method used to compute the number of occurrences associated to each vertex after the propagation of the given number of occurences.

Methods inherited from class slib.graph.algo.extraction.rvf.RVF

getRV, getRV, getRVnb, getWalkConstraint, setWalkConstraint

Methods inherited from class java.lang.Object

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

Constructor Detail

RVF_DAG

public RVF_DAG(G g,
       WalkConstraint wc)

Create a basic RVF object considering an acyclic graph and a only one type of relationships to consider during the traversal. Note that graph acyclicity is required to ensure coherency but is not evaluated.

Parameters:

g - the Semantic Graph to consider

wc - the walk constraint defining the way to reach the vertices which must be returned by the object

Method Detail

getAllRV

public Map<org.openrdf.model.URI,Set<org.openrdf.model.URI>> getAllRV()
                                                               throws SLIB_Ex_Critic

Compute the set of reachable vertices for each vertices contained in the graph according to the specified constraint associated to the instance in use. Exclusive process, i.e. the process doesn't consider that vertex v is contained in the set of reachable vertices from v. Optimized through a topological ordering

Returns:

an Map key V value the set of vertices reachable from the key

Throws:

SLIB_Ex_Critic

getTerminalVertices

public Map<org.openrdf.model.URI,Set<org.openrdf.model.URI>> getTerminalVertices()

Return the set of terminal vertices (leaves) reachable. Only the nodes which are involved in a relationships which is accepted in the global configuration will be evaluated. Self-loop are not considered. Therefore if p is an accepted predicate if a node i is only involved in a relationship i p i, it will be considered has a leave. It is important to stress that only nodes involved in the considered relationships will be considered. Therefore if the RVF is set to rdfs:subClassOf out all nodes which are not associated to an rdfs:subClassOf relationship will not be processed (even if they are associated to rdf:type relationships). This is important for instance if you use such a method to find all the leaves which are subsumed by a specific class. In this case if the DAF is not rooted you can have isolated class (which does not have ancestors or descendants) which are not considered in the results provided by this method.

Returns:

the leaves for each vertices

computeNbPathLeadingToAllVertices

public Map<org.openrdf.model.URI,Integer> computeNbPathLeadingToAllVertices()
                                                                     throws SLIB_Ex_Critic

Returns:

@throws SLIB_Ex_Critic

Throws:

SLIB_Ex_Critic

propagateNbOccurences

public Map<org.openrdf.model.URI,Integer> propagateNbOccurences(Map<org.openrdf.model.URI,Integer> nbOccurrence)
                                                         throws SLIB_Ex_Critic

Method used to compute the number of occurrences associated to each vertex after the propagation of the given number of occurences. The occurrence number are propagated considering a walk defined by the relationships loaded. A number of occurrences is associated to each vertices of the graph through the given inputs. The occurrences number are then summed considering walks starting from the terminal vertices.

Parameters:

nbOccurrence - ResultStack of type Double representing the number of occurrences of each vertices

Returns:

ResultStack of type Double representing the number occurrences propagated of each vertices

Throws:

SLIB_Ex_Critic