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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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