Left Corner Parser
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Left Corner Parser
In computer science, a left corner parser is a type of chart parser used for parsing context-free grammars In formal language theory, a context-free grammar (CFG) is a formal grammar whose production rules are of the form :A\ \to\ \alpha with A a ''single'' nonterminal symbol, and \alpha a string of terminals and/or nonterminals (\alpha can be empt .... It combines the top-down and bottom-up approaches of parsing. The name derives from the use of the left corner of the grammar's production rules. An early description of a left corner parser is "A Syntax-Oriented Translator" by Peter Zilahy Ingerman. References * ;Specific Parsing algorithms {{comp-sci-stub ...
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Computer Science
Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical disciplines (including the design and implementation of Computer architecture, hardware and Computer programming, software). Computer science is generally considered an area of research, academic research and distinct from computer programming. Algorithms and data structures are central to computer science. The theory of computation concerns abstract models of computation and general classes of computational problem, problems that can be solved using them. The fields of cryptography and computer security involve studying the means for secure communication and for preventing Vulnerability (computing), security vulnerabilities. Computer graphics (computer science), Computer graphics and computational geometry address the generation of images. Progr ...
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Chart Parser
In computer science, a chart parser is a type of parser suitable for ambiguous grammars (including grammars of natural languages). It uses the dynamic programming approach—partial hypothesized results are stored in a structure called a chart and can be re-used. This eliminates backtracking and prevents a combinatorial explosion. Chart parsing is generally credited to Martin Kay. Types of chart parsers A common approach is to use a variant of the Viterbi algorithm. The Earley parser is a type of chart parser mainly used for parsing in computational linguistics, named for its inventor. Another chart parsing algorithm is the Cocke-Younger-Kasami (CYK) algorithm. Chart parsers can also be used for parsing computer languages. Earley parsers in particular have been used in compiler-compilers where their ability to parse using arbitrary Context-free grammars eases the task of writing the grammar for a particular language. However their lower efficiency has led to people avoiding ...
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Context-free Grammars
In formal language theory, a context-free grammar (CFG) is a formal grammar whose production rules are of the form :A\ \to\ \alpha with A a ''single'' nonterminal symbol, and \alpha a string of terminals and/or nonterminals (\alpha can be empty). A formal grammar is "context-free" if its production rules can be applied regardless of the context of a nonterminal. No matter which symbols surround it, the single nonterminal on the left hand side can always be replaced by the right hand side. This is what distinguishes it from a context-sensitive grammar. A formal grammar is essentially a set of production rules that describe all possible strings in a given formal language. Production rules are simple replacements. For example, the first rule in the picture, :\langle\text\rangle \to \langle\text\rangle = \langle\text\rangle ; replaces \langle\text\rangle with \langle\text\rangle = \langle\text\rangle ;. There can be multiple replacement rules for a given nonterminal symbol. The l ...
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Left Corner
In formal language theory, the left corner of a production rule in a context-free grammar is the left-most symbol on the right side of the rule.9.3 Using Left-corner Tables
Patrick Blackburn and Kristina Striegnitz, Natural Language Processing Techniques in Prolog For example, in the rule ''A→Xα'', ''X'' is the left corner. The left corner table associates to a symbol all possible left corners for that symbol, and the left corners of those symbols, etc. Given the grammar :S → VP :S → NP VP :VP → V NP :NP → DET N the left corner table is as follows. Left corners are used to add bottom-up filtering to a , or top-down filtering to a

Academic Press
Academic Press (AP) is an academic book publisher founded in 1941. It was acquired by Harcourt, Brace & World in 1969. Reed Elsevier bought Harcourt in 2000, and Academic Press is now an imprint of Elsevier. Academic Press publishes reference books, serials and online products in the subject areas of: * Communications engineering * Economics * Environmental science * Finance * Food science and nutrition * Geophysics * Life sciences * Mathematics and statistics * Neuroscience * Physical sciences * Psychology Well-known products include the ''Methods in Enzymology'' series and encyclopedias such as ''The International Encyclopedia of Public Health'' and the ''Encyclopedia of Neuroscience''. See also * Akademische Verlagsgesellschaft (AVG) — the German predecessor, founded in 1906 by Leo Jolowicz (1868–1940), the father of Walter Jolowicz Walter may refer to: People * Walter (name), both a surname and a given name * Little Walter, American blues harmonica player Marion Wa ...
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New York City
New York, often called New York City or NYC, is the List of United States cities by population, most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the List of United States cities by population density, most densely populated major city in the United States, and is more than twice as populous as second-place Los Angeles. New York City lies at the southern tip of New York (state), New York State, and constitutes the geographical and demographic center of both the Northeast megalopolis and the New York metropolitan area, the largest metropolitan area in the world by urban area, urban landmass. With over 20.1 million people in its metropolitan statistical area and 23.5 million in its combined statistical area as of 2020, New York is one of the world's most populous Megacity, megacities, and over 58 million people live within of the city. New York City is a global city, global Culture of New ...
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Springer Science+Business Media
Springer Science+Business Media, commonly known as Springer, is a German multinational publishing company of books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing. Originally founded in 1842 in Berlin, it expanded internationally in the 1960s, and through mergers in the 1990s and a sale to venture capitalists it fused with Wolters Kluwer and eventually became part of Springer Nature in 2015. Springer has major offices in Berlin, Heidelberg, Dordrecht, and New York City. History Julius Springer founded Springer-Verlag in Berlin in 1842 and his son Ferdinand Springer grew it from a small firm of 4 employees into Germany's then second largest academic publisher with 65 staff in 1872.Chronology
". Springer Science+Business Media.
In 1964, Springer expanded its business internationally, o ...
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Union College
Union College is a private liberal arts college in Schenectady, New York. Founded in 1795, it was the first institution of higher learning chartered by the New York State Board of Regents, and second in the state of New York, after Columbia College (formerly King's College). In the 19th century, it became known as the "Mother of Fraternities",Somers (2003), p. 304 as three of the earliest Greek letter societies were established there. The school was once referred to as one of the " Big Four" alongside Harvard University, Yale University and Princeton University, before the Civil War and a financial scandal led to its fall from grace and the top national rankings. Union began enrolling women in 1970, after 175 years as an all-male institution. The college offers a liberal arts curriculum across 21 academic departments, as well as opportunities for interdepartmental majors and self-designed organizing theme majors. It offers a wide array of courses in the humanities, social sc ...
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Schenectady, New York
Schenectady () is a city in Schenectady County, New York, United States, of which it is the county seat. As of the 2020 census, the city's population of 67,047 made it the state's ninth-largest city by population. The city is in eastern New York, near the confluence of the Mohawk and Hudson rivers. It is in the same metropolitan area as the state capital, Albany, which is about southeast. Schenectady was founded on the south side of the Mohawk River by Dutch colonists in the 17th century, many of whom came from the Albany area. The name "Schenectady" is derived from the Mohawk word ''skahnéhtati'', meaning "beyond the pines" and used for the area around Albany, New York. Residents of the new village developed farms on strip plots along the river. Connected to the west by the Mohawk River and Erie Canal, Schenectady developed rapidly in the 19th century as part of the Mohawk Valley trade, manufacturing, and transportation corridor. By 1824, more people worked in manufac ...
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