Isomorphism Test for Digraphs with Weighted Edges

Author Adolfo Piperno

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Adolfo Piperno
  • Dipartimento di Informatica, La Sapienza Università di Roma, Via Salaria 113, I-00198 Rome (Italy)

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Adolfo Piperno. Isomorphism Test for Digraphs with Weighted Edges. In 17th International Symposium on Experimental Algorithms (SEA 2018). Leibniz International Proceedings in Informatics (LIPIcs), Volume 103, pp. 30:1-30:13, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2018)


Colour refinement is at the heart of all the most efficient graph isomorphism software packages. In this paper we present a method for extending the applicability of refinement algorithms to directed graphs with weighted edges. We use {Traces} as a reference software, but the proposed solution is easily transferrable to any other refinement-based graph isomorphism tool in the literature. We substantiate the claim that the performances of the original algorithm remain substantially unchanged by showing experiments for some classes of benchmark graphs.

Subject Classification

ACM Subject Classification
  • Mathematics of computing → Graph theory
  • Computing methodologies → Combinatorial algorithms
  • Practical Graph Isomorphism
  • Weighted Directed Graphs
  • Partition Refinement


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