Graph similarity calculation system, method, and program

Abstract

The similarity between graphs having an extremely large number of nodes, such as an SNS, a link of WWW, etc., can be obtained within a reasonable time. A unique value is provided to a label of a node in a graph. Preferably, the value is a fixed-length bit string. In this case, the length of the bit string is selected to be sufficiently larger than the number of digits by which types of labels can be expressed. With respect to one graph, nodes of the graph are sequentially visited by an existing graph search method, such as a depth-first search, a breadth-first search, and the like. At this time, in the system, when one specific node is visited, a calculation is performed for bit string label values of all nodes adjacent to the specific node and the bit string label value of the specific node, to obtain a bit string value. The hash calculation is performed for the calculated bit string value and the original bit string label value of the node to obtain another bit string label value, and this value becomes the label value of the node. After finishing the visit to all nodes in one graph, the label values of all nodes are rewritten. When the same treatment is performed for another graph which becomes a target of the graph similarity comparison, label values of all nodes in this graph are rewritten. Therefore, with respect to one graph, a ratio of label values which are identical to the label values in another graph, per all nodes is calculated to obtain the similarity.

Description

technical field [0001] The present invention relates to calculating or evaluating the similarity of objects in a data structure represented as a graph on a computer. Background technique [0002] A graph is a mathematical object including vertices (also called nodes) with labels for mutual identification and edges (also called edges, branches, and links) connecting the vertices. When considering real objects, it can be known that, for example, a road map, Chemical formulas and the like are represented by diagrams. [0003] For example, in a road map, intersections can be considered as nodes and roads as edges. In a chemical formula, elements can be considered as nodes, and the connections between elements are edges. If considered in this way, it can be seen that the application of graphs can be found in a very wide range of fields such as genes, protein structures, circuits, geography, and architecture. [0004] Recently, graph construction is gradually applied to social ...

AI Technical Summary

Problems solved by technology

However, this technical method uses the unique properties of these circuits such as master nodes, and it is difficult to extend to general graph comparisons.

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