An Implementation of Deterministic Tree Automata Minimization

  • Rafael C. Carrasco
  • Jan Daciuk
  • Mikel L. Forcada
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4783)


A frontier-to-root deterministic finite-state tree automaton (DTA) can be used as a compact data structure to store collections of unranked ordered trees. DTAs are usually sparser than string automata, as most transitions are undefined and therefore, special care must be taken in order to minimize them efficiently. However, it is difficult to find simple and detailed descriptions of the minimization procedure in the published literature. Here, we fully describe a simple implementation of the standard minimization algorithm that needs a time in \(\mathcal{O}(|A|^2)\), with |A| being the size of the DTA.


sminimal deterministic tree automata minimization of automata 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Rafael C. Carrasco
    • 1
  • Jan Daciuk
    • 2
  • Mikel L. Forcada
    • 3
  1. 1.Dep. de Lenguajes y Sistemas Informáticos, Universidad de Alicante, E-03071 AlicanteSpain
  2. 2.Knowledge Engineering Department, Gdańsk University of Technology, Ul. G. Narutowicza 11/12, 80-952 GdańskPoland
  3. 3.Dep. de Llenguatges i Sistemes informàtics, Universitat d’Alacant, E-03071 AlacantSpain

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