How Expressions Can Code for Automata

  • Sylvain Lombardy
  • Jacques Sakarovitch
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2976)


In this paper we investigate how it is possible to recover an automaton from a rational expression that has been computed from that automaton. The notion of derived term of an expression, introduced by Antimirov, appears to be instrumental in this problem. The second important ingredient is the co-minimization of an automaton, a dual and generalized Moore algorithm on non-deterministic automata. If an automaton is then sufficiently “decorated”, the combination of these two algorithms gives the desired result. Reducing the amount of “decoration” is still the object of ongoing investigation.


Rational Expression Regular Expression Russian Mathematical Regular Language Empty Word 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Sylvain Lombardy
    • 1
  • Jacques Sakarovitch
    • 2
  1. 1.LIAFA, Université Paris 7Paris cedex 05France
  2. 2.LTCI, CNRS / ENSTParis Cedex 13France

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