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A note on finite-valued and finitely ambiguous transducers

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Abstract

We look at some decision problems concerning nondeterministic finite transducers. The problems concern finite-valuedness, finite ambiguity, equivalence, etc. For a fixedk, we give a polynomial time algorithm for deciding whether or not a transducer isk-valued. The result holds when “valued” is replaced by “ambiguous”. In fact, the following problems are decidable: 1) Given a transducer, is itk-ambiguous for somek? 2) Given two finitely ambiguous transducers, are they equivalent? For unambiguous transducers, equivalence is decidable in polynomial time.

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Authors and Affiliations

  1. Department of Computer Science, SUNY at Buffalo, Amherst, NY, USA

    Eitan M. Gurari

  2. Department of Computer Science, University of Minnesota, Minneapolis, MN, USA

    Oscar H. Ibarra

Authors
  1. Eitan M. Gurari
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  2. Oscar H. Ibarra
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Additional information

Work supported by NSF Grant MCS7909967.

Work supported by NSF Grant MCS8102853.

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Gurari, E.M., Ibarra, O.H. A note on finite-valued and finitely ambiguous transducers. Math. Systems Theory 16, 61–66 (1983). https://doi.org/10.1007/BF01744569

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  • DOI: https://doi.org/10.1007/BF01744569

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