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GraphDiff Class

Implementation of a Graph Difference algorithm for RDF Graphs.
Inheritance Hierarchy
SystemObject
  VDS.RDFGraphDiff

Namespace:  VDS.RDF
Assembly:  dotNetRDF (in dotNetRDF.dll) Version:
Syntax
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public class GraphDiff

The GraphDiff type exposes the following members.

Constructors
  NameDescription
Public methodGraphDiff
Initializes a new instance of the GraphDiff class
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Methods
  NameDescription
Public methodStatic memberComputeMSGs
Computes MSGs for a Graph.
Public methodDifference
Calculates the Difference between the two Graphs i.e. the changes required to get from the 1st Graph to the 2nd Graph.
Public methodEquals
Determines whether the specified object is equal to the current object.
(Inherited from Object.)
Protected methodFinalize
Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.
(Inherited from Object.)
Public methodGetHashCode
Serves as the default hash function.
(Inherited from Object.)
Public methodGetType
Gets the Type of the current instance.
(Inherited from Object.)
Protected methodMemberwiseClone
Creates a shallow copy of the current Object.
(Inherited from Object.)
Public methodToString
Returns a string that represents the current object.
(Inherited from Object.)
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Remarks

This algorithm is broadly based upon the methodology fror computing differences in RDF Graphs described in the RDFSync paper by Tummarello et al. This is an implementation purely of a difference algorithm and not the synchronisation aspects described in their paper. Main difference between their algorithm and mine is that mine does not make the input Graphs lean as it is concerned with showing the raw differences between the Graphs and does not concern itself with whether the differences may be semantically irrelevant.

To understand this consider the following Graphs:

Graph A

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_:autos1 rdfs:label "Rob" .

Graph B

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_:autos1 rdfs:label "Rob" .
_:autos2 rdfs:label "Rob" .

Given these Graphs computing the Graph Difference between A and B would report an Added MSG (Minimal Spanning Graph) when in fact the 2nd Graph is non-lean and could be reduced to the same as the 1st Graph.

See Also