Results 21 to 30 of about 318,670 (335)
A survey of normal form covers for context-free grammars [PDF]
, 1980 An overview is given of cover results for normal forms of context-free grammars. The emphasis in this paper is on the possibility of constructing ɛ-free grammars, non-left-recursive grammars and grammars in Greibach normal form. Among others it is proved
Nijholt, Anton
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A Context-Free Grammar of One Rhythmic Model of Russian Verse
Моделирование и анализ информационных систем, 2012 A formal model of the Russian verse based on the accentual segmentation of its structure is offered and considered. A context-free grammar (in N. Chomsky’s sense) which generates correct rhythmic forms of the presented model is constructed.
V. N. Boykov
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From left-regular to Greibach normal form grammars [PDF]
, 1979 Each context-free grammar can be transformed to a context-free grammar in Greibach normal form, that is, a context-free grammar where each right-hand side of a prorfuction begins with a terminal symbol and the remainder of the right-hand side consists of
Nijholt, A.
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Spurious Ambiguity and Focalization [PDF]
Computational Linguistics, 2018 Spurious ambiguity is the phenomenon whereby distinct derivations in grammar may assign the same structural reading, resulting in redundancy in the parse search space and inefficiency in parsing.
Glyn Morrill, Oriol Valentín
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MINIMIZATION OF CONTEXT-FREE GRAMMARS
Prikladnaya Diskretnaya Matematika, 2019 Summary: This paper solves the problem of transforming the initial context-free grammar (CF-grammar) without excess characters into equivalent CF-grammar with less complexity. To solve this problem, the following relation on the set of a CF-grammar non-terminals is introduced: \(E = \{(X,Y): (X=Y) \vee (X\to \alpha\Leftrightarrow Y\to \beta \wedge\vert
Ryazanov, Yu. D., Nazina, S. V.
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Absence of phase transition in random language model
Physical Review Research, 2022 The random language model, proposed as a simple model of human languages, is defined by the averaged model of a probabilistic context-free grammar. This grammar expresses the process of sentence generation as a tree graph with nodes having symbols as ...
Kai Nakaishi, Koji Hukushima
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On a property of probabilistic context‐free grammars [PDF]
International Journal of Mathematics and Mathematical Sciences, 1983 It is proved that for a probabilistic context‐free language L(G), the population density of a character (terminal symbol) is equal to its relative density in the words of a sample S from L(G) whenever the production probabilities of the grammar G are estimated by the relative frequencies of the corresponding productions in the sample.
Chaudhuri, R., Rao, A. N. V.
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Equivalent Transformations and Regularization in Context-Free Grammars
Cybernetics and Information Technologies, 2015 Regularization of translational context-free grammar via equivalent transformations is a mandatory step in developing a reliable processor of a formal language defined by this grammar.
Fedorchenko Ludmila, Baranov Sergey
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On the covering of left recursive grammars [PDF]
, 1976 In this paper we show that some prevailing ideas on the elimination of left recursion in a context-free grammar are not valid. An algorithm and a proof are given to show that every proper context-free grammar is covered by a non-left-recursive ...
Nijholt, A.
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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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