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On the complexity of parallel parsing of general context-free languages

Wojciech Rytter
1986 Theoretical Computer Science  
Let T(n) be the time to recognize context-free languages on a parallel random-access machine without write conflicts (P-RAM) using a polynomial number of processors. We assume that T(n)=l~(log n).  ...  A related result is a parallel time log n computation of the transitive closure of directed graphs having special structure. * On leave from the Institute  ...  Acknowledgment The author thanks M.S. Paterson for his comments on this paper.  ... 
doi:10.1016/0304-3975(86)90155-6 fatcat:at2tjppjxnaajheqq34hyxnsja

Page 3379 of Mathematical Reviews Vol. , Issue 92f [page]

1992 Mathematical Reviews  
Summary: “A new general context-free parsing algorithm is pre- sented which runs in linear time and space on every LR(k) gram- mar without using any lookahead and without making use of the LR property.  ...  (NL-NIJM-C) A general context-free parsing algorithm running in linear time on every LR(k) grammar without using lookahead. Theoret. Comput. Sci. 82 (1991), no. 1, Algorithms Automat.  ... 

Page 378 of Computational Linguistics Vol. 18, Issue 3 [page]

1992 Computational Linguistics  
Furthermore, no comparison at all is offered to the reader with the existing literature on parallel context-free grammar parsing.  ...  Note inci- dentally that, in discussing the importance of null productions, the author claims that a general context-free grammar can be exponentially more succinct than a context-free grammar in <-free  ... 

Page 761 of Mathematical Reviews Vol. , Issue 83b [page]

1983 Mathematical Reviews  
The language Gy is also hardest in the sense of space complexity. The language G, is especially attractive because of its relation to the hardest context-free language Ly in the paper by S.  ...  It follows that there are context-free languages which can be recognized by pushdown automata of size O(np), but which cannot be generated by context-free grammars of size smaller than O(n*p); and that  ... 

Page 954 of Mathematical Reviews Vol. 55, Issue 3 [page]

1978 Mathematical Reviews  
On the other hand, if a permitting context is added to the tables, then the resulting family of languages coin- cides with the family of recurrent context-free programmed languages, a subfamily of context-free  ...  method for parsing arbitrary context-free languages, Earley’; | algorithm.  ... 

Page 1291 of Mathematical Reviews Vol. 58, Issue 2 [page]

1979 Mathematical Reviews  
Transformations on (context-free) grammars are often used to solve problems related to grammars, languages and parsing.  ...  A modification of Early’s parsing algorithm is proposed which can be applied to “extended” context-free grammars. The extension consists of rules of the form: (1) A—a[ B]y and (2) A{a},.  ... 

Rational index of bounded-oscillation languages [article]

Ekaterina Shemetova, Alexander Okhotin, Semyon Grigorev
2020 arXiv   pre-print
We obtain upper bounds on the values of the rational index for general bounded-oscillation languages and for some of its previously studied subclasses.  ...  The rational index of a context-free language L is a function f(n), such that for each regular language R recognized by an automaton with n states, the intersection of L and R is either empty or contains  ...  For example, there are context-free languages which admit more efficient parallel algorithms in comparison with the general case of context-free recognition [19, 20, 23] .  ... 
arXiv:2012.03567v1 fatcat:6og66bybfjgadec44uulheeowu

Page 3209 of Mathematical Reviews Vol. , Issue 98E [page]

1998 Mathematical Reviews  
Summary: “The computational complexity of languages generated by parallel communicating grammar systems (PCGs) with regular components is investigated.  ...  In particular, the class of RC-UPGs gives a very simple grammatical characterization of the class of deterministic context-free languages.  ... 

Page 5138 of Mathematical Reviews Vol. , Issue 97H [page]

1997 Mathematical Reviews  
It is based on the classical Cocke-Kasami- Younger parse algorithm for context-free languages, and exploits fast Boolean matrix multiplication, ending up with an algorithm running in time O(n>*"), which  ...  While being relatively simple devices, they have stronger expressive capacities than context-free grammars. In the article, a parsing algorithm is developed for tree- adjoining languages.  ... 

Page 377 of Computational Linguistics Vol. 23, Issue 3 [page]

1997 Computational Linguistics  
The inversion trans- duction grammar formalism skips directly to a context-free, rather than finite-state, base and permits one extra degree of ordering flexibility, while retaining properties necessary  ...  grammar formalism for bilingual language modeling of sentence-pairs, and (2) the concept of bilingual parsing with a variety of parallel corpus analysis applications.  ... 

Page 5689 of Mathematical Reviews Vol. , Issue 93j [page]

1993 Mathematical Reviews  
of context-free languages.  ...  The article considers the complexity of deciding structural containment and equivalence for two given context-free grammars.  ... 

Page 80 of Computational Linguistics Vol. 14, Issue 2 [page]

1988 Computational Linguistics  
The book opens with a diagnosis of the current state of work on parsing context-free languages.  ...  Two kinds of algorithms for context-free languages are avail- able: specific algorithms for programming languages, and general algorithms intended to handle any context- free grammar.  ... 

PNEPs, NEPs for Context Free Parsing: Application to Natural Language Processing [chapter]

Alfonso Ortega, Emilio del Rosal, Diana Pérez, Robert Mercaş, Alexander Perekrestenko, Manuel Alfonseca
2009 Lecture Notes in Computer Science  
This work tests the suitability of NEPs to parse languages. We propose PNEP, a simple extension to NEP, and a procedure to translate a grammar into a PNEP that recognizes the same language.  ...  These parsers based on NEPs do not impose any additional constrain to the structure of the grammar, which can contain all kinds of recursive, lambda or ambiguous rules.  ...  PNEPs seem to be an appropiate and natural approach to tackle both parsing of context-free languages and the syntactic processing of natural languages.  ... 
doi:10.1007/978-3-642-02478-8_59 fatcat:xw2jwhaqlvdanbu5bzli4konje

Parallel parsing of operator precedence grammars

Alessandro Barenghi, Stefano Crespi Reghizzi, Dino Mandrioli, Matteo Pradella
2013 Information Processing Letters  
In this paper we focus on their local parsability property, i.e, the fact that any substring s of a longer one x.s.y can be parsed independently of its context without the risk of invalidating the partial  ...  parsing when analyzing another portion of the whole string.  ...  Introduction Floyd's Operator Precedence grammars (OPGs) and their languages (OPLs) were introduced half a century ago [6, 8] and are still used [12] to support efficient deterministic parsing of context-free  ... 
doi:10.1016/j.ipl.2013.01.008 fatcat:2b4s5zumi5gadnvbdikyujohsa

Parse views with Boolean grammars

Andrew Stevenson, James R. Cordy
2015 Science of Computer Programming  
We propose an enhancement to current parsing and transformation systems by leveraging the expressive power of Boolean grammars, a generalization of context-free grammars that adds conjunction and negation  ...  In addition to naturally expressing a larger class of languages, Boolean grammars capture multiple parse trees of the same document simultaneously and the ability to switch between these parse "views".  ...  Other useful generalizations of context-free grammars have been proposed [4, 1, 7, 8] . However, the danger of grammar generalization is in the formalism becoming Turing complete.  ... 
doi:10.1016/j.scico.2013.11.007 fatcat:l4u22qvjcfaqxeglnem7m5ovqe
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