Incremental Minimization of Symbolic Automata

  • Jonathan Homburg
  • Parasara Sridhar DuggiralaEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 12031)


Symbolic automata are generalizations of finite automata that have symbolic predicates over the alphabet as transitions instead of symbols. Recently, traditional automata minimization techniques have been generalized to symbolic automata. In this paper, we generalize the incremental minimization algorithm to symbolic automata such that the algorithm can be halted at any point for obtaining a partially minimized automaton. Instead of computing the sets of equivalence classes, the incremental algorithm checks for equivalence between pairs of states and if they are equivalent, merges them into a single state. We evaluate our algorithm on SFAs corresponding to Unicode regular expressions and compare them to the state-of-the-art symbolic automata minimization implementations.



The authors would like to thank anonymous reviews for their feedback. The work done in this paper is based upon work supported by the National Science Foundation (NSF) under grant numbers CNS 1739936, 1935724. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of NSF.


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Authors and Affiliations

  1. 1.Department of Computer Science and EngineeringUniversity of ConnecticutStorrsUSA
  2. 2.Department of Computer ScienceUniversity of North Carolina Chapel HillChapel HillUSA

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