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| | <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>Freeb>bb>> Grammars |
 | | The type of grammar that can described queries (and many other interesting languages) is a <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammar(CFG). | | | For <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammars, the derivation can be more conveniently shown in the form of a tree. | | | This is what makes the grammar a <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammar. |
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http://www.cse.ohio-state.edu/~lohse/CIS321/cfg.html
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| | Probabilistic <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>Freeb>bb>> Grammars |
| | It generates the same set of parses for a text that the corresponding <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammar does, and assigns a probability to each parse. | | | Probabilistic <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammars are implemented by the | | | ) is a <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammar that associates a probability with each of its productions. |
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http://nltk.sourceforge.net/tutorial/pcfg/section-pcfg.html
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| | Mildly <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> sensitive grammar formalisms |
| | Summary: While there is conclusive proof that not all natural languages can be described by <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammars, all available evidence suggests that a very cautious extension of this complexity class is sufficient to accommodate all linguistic phenomena. | | | Friday: Linear <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> rewriting systems, Minimalist Grammars, example of a minimalist grammar | | | An introduction to mildly <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> sensitive grammar formalisms |
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http://www.ling.uni-potsdam.de/~jaeger/esslli2004
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| | Introduction |
| | There has been growing interest over the last few years in learning learning some formal grammar from text, sequences or structured data, but even if the regular case (corresponding to finite state automata) has been well studied, this has not been the case for more expressive classes such as <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammars. | | | -grams for language modeling tasks with interesting results ( ``A Hybrid Language Model Based on Stochastic <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>Freeb>bb>> Grammars). | | | Yet long term dependencies, palindromic structures, parenthesis are all internal structures that may appear in a wide range of applications and are better described by <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammars. |
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http://ilk.uvt.nl/~mvzaanen/ECMLPKDD/introduction.html
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| | <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> schemas for data-XML |
| | refers to <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammars, on which this proposal is based. | | | A <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammar (CFG) is often the most compact and easiest way to describe some structure. | | | Not all languages (or structures) are <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>>, but it is usually worth the trouble making them so (or nearly). |
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http://www.w3.org/People/Bos/Schema/schemas
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| | <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> - OneLook Dictionary Search |
| | Phrases that include <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> : <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammar, <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> language, <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammars, probabilized <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammar, stochastic <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammar | | | Tip: Click on the first link on a line below to go directly to a page where "<<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>>" is defined. | | | <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> : <<b>bb>>Freeb>bb>> On-line Dictionary of Computing [ home, info ] |
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http://www.onelook.com/?w=context+free&ls=a
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| | <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>Freeb>bb>> Languages |
| | As you recall from our definitions, a <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> language can be generated by a <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammar. | | | E generates this language, it is <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>>. | | | Apply the pumping lemma to show this language is not regular. |
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http://www.mathreference.com/lan-cfl,intro.html
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| | CMSC 451 Lecture 24, Pumping Lemma for <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>Freeb>bb>> Languages |
| | If a <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>Freeb>bb>> Grammar can be constructed to exactly generate the strings in a language, then the language is <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>Freeb>bb>>. | | | If a PDA machine can be constructed to exactly accept a language, then the language is a <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>Freeb>bb>> Language. | | | T For the Pumping Lemma, the statement "A" is "L is a <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>Freeb>bb>> Language", The statement "<<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>><<b>bb>>Bb>bb>>b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>" is a statement from the Predicate Calculus. |
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http://www.cs.umbc.edu/~squire/s01-451/cs451_l24.html
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| | Translation Completeness for <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>Freeb>bb>> Grammars |
| | Sections 7 and 8 work out conditions that do guarantee this (for compositional grammars based on <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammars, which are presented in the next section). | | | A CFG grammar can be rephrased as a compositional grammar in the following way: (i) The nonterminals become the syntactic categories of the compositional grammar. | | | ]), because its inclusion would obscure our general discussion, and there is no need for a separate semantic component in the <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> of controlled languages where syntactic elements can be assumed to be unambiguous. |
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http://www.essex.ac.uk/web-sls/papers/97-04/97-04.html
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| | chp7-sec3 |
| | <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammars often contain collection of sentences in which phrases are nested in matched pairs. | | | For any <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammar G, one can decide whether L(G) is finite or infinite. |
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http://www.cmpe.boun.edu.tr/courses/cmpe350/common/chp7sec3.htm
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| | <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> |
| | Not dependent on <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>; a <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammar is one in which the syntax of a symbol is the same regardless of it <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> (that is, regardless of what other symbols occur before it or after it). | | | © 2004 HitScreen.com - Your <<b>bb>>Freeb>bb>> Hit Counter |
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http://www.hitscreen.com/dictionary/Context_15free.html
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| | Introduction to BeRP |
| | The BeRP recognizer consists of six components: the RASTA-PLP feature extractor, a multi-layer perceptron phonetic likelihood estimator, a viterbi decoder called Y0, an HMM pronunciation lexicon, a bigram or stochastic <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammar language model, and the natural language backend, which includes a database of restaurants. | | | The user can then ask for more information about the restaurant. | | | The system runs on a SPARCstation, although for speed we usually offload the phonetic likelihood estimation to special purpose neural network hardware. |
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http://www.icsi.berkeley.edu/real/berp.html
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| | <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>Freeb>bb>> Grammars |
| | Although lists may require more processing to recognize, they allow grammars to be modified dynamically for such things as filenames that change frequently and often depend upon <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>. | | | Rather than send text strings to the engine, which is too slow, the grammar sends a list of structures filled with the equivalent operations and symbols. | | | For example, if the list contains "Bob Marks" and "Fred Smith" at run time, the speaker can say "Send mail to Bob Marks" and "Send mail to Fred Smith." |
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http://www.text-reader.com/ttshelp/contxtFree.html
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| | RAGS - Survey of Grammar Models |
| | Indexed grammars are another less commonly used model, in which the application of otherwise <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> rules can be regulated by means of index lists, which are attached to the nonterminals much like inherited attributes in an extended attribute grammar. | | | One large family of grammar models increase the power of CFGs by placing restrictions on the order in which the <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> rules can be applied during derivation; a drawback of this approach is that the <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-dependent factors are invisible in the parse tree. | | | The only significance of the initial Christiansen grammar is that it becomes the language attribute of the root node of the parse tree. |
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http://web.cs.wpi.edu/~jshutt/thesis/survey.html
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| | A brief introduction to definite clause grammars and definite clause translation grammars |
| | Informally, attribute grammars are sometimes described as <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammars with parameters on the non-terminals. | | | An attribute grammar is a <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammar in which the nodes of the parse tree carry attributes (annotations in the form of name-value pairs). | | | DCTGs closely resemble attribute grammars as described by [Knuth 1968] and later writers and it is a bit easier to handle complex or voluminous attribute value functions in DCTGs than in DCGs. |
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http://www.w3.org/People/cmsmcq/2004/lgintro.html
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| | Entry Wayner:1995:STS from cryptologia.bib |
| | This paper discusses the implications of the result and presents a practical solution for securely hiding information from inspection", abstract-2 = "The author proposes a system of steganography based on <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammars. | | | An example is given based on English text generated using these ideas.", acknowledgement = ack-nhfb, keywords = "<<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammars; cryptography; Turing machines; information hiding; steganography", language = "English", romanvolume = "XIX", subject = "strong theoretical steganography; terabit networks; mimic functions; <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammars; Blum integers; RSA; natural language processing", } | | | One technique for practicing this obfuscation, Mimic Functions, is derived from <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>Freeb>bb>> Grammars and can be as secure as inverting RSA or factoring Blum integers. |
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http://www.math.utah.edu/ftp/pub/tex/bib/idx/cryptologia/19/3/285-299.html
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| | Formal grammar - Wikipedia, the <<b>bb>>freeb>bb>> encyclopedia |
| | For example, for <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammars there are well-known algorithms to generate efficient LL parsers and LR parsers. | | | An analytic grammar, in contrast, is a set of rules that assume an arbitrary string to be given as input, and which successively reduce or analyze that input string yielding a final boolean, "yes/no" result indicating whether or not the input string is a member of the language described by the grammar. | | | Affix grammars and attribute grammars allow rewrite rules to be augmented with semantic attributes and operations, useful both for increasing grammar expressiveness and for constructing practical language translation tools. |
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http://en.wikipedia.org/wiki/Formal_grammar
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| | Attribute grammar - Wikipedia, the <<b>bb>>freeb>bb>> encyclopedia |
| | Semantics of <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammars, by Don Knuth, is the original paper introducing attributed grammars. | | | In a practical way, an attribute grammar defines the information that will need to be in the abstract syntax tree in order to successfully perform semantic analysis. | | | When constructing a language translation tool, such as a compiler, an attribute grammar is the formal expression of the syntax-derived semantic checks associated with a grammar. |
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http://en.wikipedia.org/wiki/Attribute_grammar
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| | The Natural Language Processing Dictionary |
| | The process is as follows with <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammars: pick a non-terminal X in the current string (or sentential form) and a grammar rule whose left-hand side is that non-terminal X. Replace X in the current string by the right-hand side of the grammar rule, to obtain a new current string. | | | The process is similar with <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-sensitive grammarsand unrestricted grammars, except that instead of picking a non-terminal X in the current string, we find a substring of the current string that matches the left-hand side of some <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-sensitive or unrestricted grammar rule, and replace it with the right-hand side of that grammar rule. | | | A grammar is a formalism for describing the syntax of a language. |
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http://www.cse.unsw.edu.au/~billw/nlpdict.html
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| | Attribute Grammar Systems Compilers Programming Computers |
| | <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>Contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammars can be described on a primary <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> level augment | | | - The formalism for the to attribute grammars related Affix Grammar over Finite Lattices developed at the University of Nijmegen is being applied to natural-language processing. | | | - The system generates efficient incremental attribute evaluators and was written by one of the attribute-grammar formalizers. |
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http://www.iaswww.com/ODP/Computers/Programming/Compilers/Attribute_Grammar_Systems
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| | Datum grammar acceptors |
| | For a more substantial example, study the acceptor for the <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammar of Scheme transliterated from the R4RS formal syntax. | | | , contains a <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> grammar and returns an acceptor for the grammar. | | | The returned acceptor is a predicate that takes a datum and returns a boolean indicating if the datum can be generated by the given grammar. |
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http://www.cs.indiana.edu/proglang/scheme/grammar.html
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| | RAGS - Survey of Grammar Models |
| | Indexed grammars are another less commonly used model, in which the application of otherwise <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> rules can be regulated by means of index lists, which are attached to the nonterminals much like inherited attributes in an extended attribute grammar. | | | One large family of grammar models increase the power of CFGs by placing restrictions on the order in which the <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-<<b>bb>>freeb>bb>> rules can be applied during derivation; a drawback of this approach is that the <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-dependent factors are invisible in the parse tree. | | | In a definite clause grammar, <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>-dependent language features are described by the explicit imposition of logical constraints on a CFG; thus, definite clause grammars reject the inheritance/synthesis distinction even in concept. |
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http://www.cs.wpi.edu/~jshutt/thesis/survey.html
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| | AN LL(1) PARSER GENERATOR WITH LOOKAHEAD - LALL |
| | In <<<<b>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>>contextb>bb>>bb>bb>>><b>bb>b>bb>>bb>bb>>>> <<b>bb>>freeb>bb>> grammars, parser generators have dealt with ambiguity by assigning a priority to one of the distinct trees that represent the input sentence when the parser is generated. | | | Two grammars may describe the same language, and one grammar be ambiguous, and one not be ambiguous (the meaning attached to the tokens within the grammar is what is ambiguous). | | | A parse tree is one possible interpretation of a sentence of the language, and represents the path of the parser in the grammar as it scans the input. |
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http://www.gen7software.com/lall/lallthes.htm
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