Algorithms for finding frequent and/or interesting subgraphs in a single large graph scenario are computationally intensive because of the graph isomorphism and the subgraph isomorphism problem. These problems are compounded by the size of most real-world datasets which have sizes in the order of 10 or 10. The SUBDUE algorithm developed by Cook and Holder finds the most compressing subgraph in ...

The methodology of positioning graph vertices relative to each other to solve the problem of determining isomorphism of two undirected graphs is developed. Based on the position of the vertex in one of the graphs, it is determined the corresponding vertex in the other graph. For the selected vertex of the undirected graph, define the neighborhoods of the vertices are defined. Next, it is constr...

The isomorphism problem is known to be efficiently solvable for interval graphs, while for the larger class of circular-arc graphs its complexity status stays open. We consider the intermediate class of intersection graphs for families of circular arcs that satisfy the Helly property. We solve the isomorphism problem for this class in logarithmic space. If an input graph has a Helly circular-ar...

In electrical engineering educational industrial applications it is often required for the students to build and analyze well-known circuits according to their syllabus. In this paper a colored graph isomorphism based model is discussed that is being developed to match two electrical circuits. The procedure involves two steps, first being, to store the circuit in the data base in form of a colo...

Normalized Laplacian matrices of graphs have recently been studied in the context of quantum mechanics as density matrices of quantum systems. Of particular interest is the relationship between quantum physical properties of the density matrix and the graph theoretical properties of the underlying graph. One important aspect of density matrices is their entanglement properties, which are respon...

Colour refinement is a simple algorithm that partitions the vertices of a graph according their “iterated degree sequence.” It has very efficient implementations, running in quasilinear time, and a surprisingly wide range of applications. The algorithm has been designed in the context of graph isomorphism testing, and it is used an important subroutine in almost all practical graph isomorphism ...

Several graph problems (e.g., steiner tree, connected domination, hamiltonian path, and isomorphism problem), which can be solved in polynomial time for distance-hereditary graphs, are NP-complete or open for parity graphs. Moreover, the metric characterizations of these two graph classes suggest an excessive gap between them. We introduce a family of classes forming an infinite lattice with re...