Continuity and Rational Functions
نویسندگان
چکیده
A word-to-word function is continuous for a class of languages V if its inverse maps V_languages to V. This notion provides a basis for an algebraic study of transducers, and was integral to the characterization of the sequential transducers computable in some circuit complexity classes. Here, we report on the decidability of continuity for functional transducers and some standard classes of regular languages. Previous algebraic studies of transducers have focused on the structure of the underlying input automaton, disregarding the output. We propose a comparison of the two algebraic approaches through two questions: When are the automaton structure and the continuity properties related, and when does continuity propagate to superclasses? 1998 ACM Subject Classification F.4.3 Formal Languages
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