Results 11 to 20 of about 767,182 (284)
Parallel context-free languages
Information and Control, 1974 <p>The relation between the family of context-free languages and the family of parallel context-free languages is examined in this paper. It is proved that the families are incomparable. Finally we prove that the family of languages of finite index is contained in the family of parallel context-free languages.</p><p>Information and ...
Siromoney, Rani, Krithivasan, Kamala
exaly +5 more sources
Mathematics, 2022 The limitations of traditional parsing architecture are well known. Even when paired with parsing methods that accept all context-free grammars (CFGs), the resulting combination for any given CFG accepts only a limited subset of corresponding character ...
Žiga Leber +3 more
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Undecidable problems concerning densities of languages [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 In this paper we prove that the question whether a language presented by a context free grammar has density, is undecidable. Moreover we show that there is no algorithm which, given two unambiguous context free grammars on input, decides whether the ...
Jakub Kozik
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Optimizing over subsequences generates context-sensitive languages
Transactions of the Association for Computational Linguistics, 2021 Phonological generalizations are finite-state. While Optimality Theory is a popular framework for modeling phonology, it is known to generate non-finite-state mappings and languages. This paper demonstrates that Optimality Theory is capable of generating
Andrew Lamont
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Regular Languages and Associative Language Descriptions [PDF]
Discrete Mathematics & Theoretical Computer Science, 2007 The Associative Language Description model (ALD) is a combination of locally testable and constituent structure ideas. It is consistent with current views on brain organization and can rather conveniently describe typical technical languages such as ...
Marcella Anselmo +2 more
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Bounded-oscillation Pushdown Automata [PDF]
Electronic Proceedings in Theoretical Computer Science, 2016 We present an underapproximation for context-free languages by filtering out runs of the underlying pushdown automaton depending on how the stack height evolves over time. In particular, we assign to each run a number quantifying the oscillating behavior
Pierre Ganty, Damir Valput
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, 2023 Context-free languages can be characterized in several ways. This article studies projective linearisations of languages of simple dependency trees, i.e., dependency trees in which a node can govern at most one node with a given syntactic function.
openaire +3 more sources
Chomsky-Schützenberger parsing for weighted multiple context-free languages
Journal of Language Modelling, 2017 We prove a Chomsky-Schützenberger representation theorem for multiple context-free languages weighted over complete commutative strong bimonoids. Using this representation we devise a parsing algorithm for a restricted form of those devices.
Tobias Denkinger
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Complexity of Problems of Commutative Grammars [PDF]
Logical Methods in Computer Science, 2015 We consider commutative regular and context-free grammars, or, in other words, Parikh images of regular and context-free languages. By using linear algebra and a branching analog of the classic Euler theorem, we show that, under an assumption that the ...
Eryk Kopczynski
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Highly Undecidable Problems For Infinite Computations [PDF]
, 2009 We show that many classical decision problems about 1-counter omega-languages, context free omega-languages, or infinitary rational relations, are $\Pi_2^1$-complete, hence located at the second level of the analytical hierarchy, and "highly undecidable".
Finkel, Olivier
core +6 more sources