Cleanup date July 2009 The pumpinglemma for contextfreelanguages , also known as the Yehoshua Bar Hillel Bar Hillel lemma , is a lemma mathematics lemma that gives a property shared by all contextfree language s. Formal statement If a language L is contextfree, then there exists some integer p 1 ... for every integer n 0. Informal statement and explanation The pumpinglemma for contextfreelanguages called just the pumpinglemma for the rest of this article describes a property that all contextfreelanguages are guaranteed to have. The property is a property of all strings in the language ... The pumpinglemma for contextfreelanguages can be used to show that certain languages ... of the contextfreelanguages. See also Pumpinglemma for regular languages Formal languages ... 2.3 Non contextfreeLanguages, pp. 115&ndash 119. DEFAULTSORT PumpingLemma For ContextFreeLanguages ... contextfreelanguages. Say s is a string of length at least p that is in the language. The pumping ... is not contextfree by using the pumpinglemma in a proof by contradiction . First, assume that math L math is contextfree. By the pumpinglemma, there exists an integer math p math which is the pumping ... that math L math is contextfree must be false. While the pumpinglemma is often a useful tool to prove ... freelanguages. If a language does not satisfy the condition given by the pumpinglemma, we have established that it is not contextfree. On the other hand, there are languages that are not contextfree, but still satisfy the condition given by the pumpinglemma. There are more powerful proof ... gives the pumpinglemma its name. Note that finite language s which are regular and hence contextfree obey the pumpinglemma trivially by having p equal to the maximum string length in L plus one. As there are no strings of this length the pumpinglemma is not violated. The pumpinglemma is often used to prove that a given language is non contextfree by showing that for each p , we can find ... more details
either a finite state machine or a regular expression for the language. See also Pumpinglemma for contextfreelanguages Formal languages Ogden s lemma Notes references References cite book ...In the theory of formal language s, the pumpingLemma mathematics lemma for regular languages describes ... , z , p , and i be as used in the Pumpinglemma for regular languages Formal statement formal statement for the pumpinglemma above. Let w in L be given by w a sup p sup b sup p sup . By the pumping ... the string ad . In terms of the pumpinglemma, the string abcd is broken into an x portion a , a y portion bc and a z portion d . General version of pumpinglemma for regular languages If a language .... Converse of lemma not true Note that while the pumpinglemma states that all regular languages ... is known as pumping . Moreover, the pumpinglemma guarantees that the length of xy will be at most p , imposing a limit on the ways in which w may be split. Finite languages trivially satisfy the pumpinglemma by having p equal to the maximum string length in L plus one. The pumpinglemma ... in question. It is one of a few pumpinglemma s, each with a similar purpose. Formal statement ... expression of the PumpingLemma. math begin array l forall L subseteq Sigma quad mbox regular L ... land y geq 1 land xy leq p land forall i geq 0 xy iz in L end array math Use of lemma The pumping ... lacks the property outlined in the pumpinglemma. For example the language L a sup n sup b sup n ... version of the pumpinglemma give a Necessary and sufficient condition necessary but not sufficient ... Lemmas Category Automata theory de PumpingLemma Regul re Sprachen hr Svojstvo napuhavanja za regularne jezike it Pumpinglemma per i linguaggi regolari he mk ... number of times to produce a new word which also lies within the same language. Specifically, the pumpinglemma says that for any regular language L there exists a constant p such that any word ... more details
In the theory of formal language s in computability theory , a pumpinglemma or pumping argument states that, for a particular language to be a member of a language class, any sufficiently long string in the language contains a section, or sections, that can be removed, or repeated any number of times, with the resulting string remaining in that language. The proofs of these lemmas typically require counting argument s such as the pigeonhole principle . The two most important examples are the pumpinglemma for regular languages and the pumpinglemma for contextfreelanguages . Ogden s lemma is a second, stronger pumpinglemma for contextfree language s. These lemma mathematics lemma s can be used to determine if a particular language is not in a given language class. However, they cannot be used to determine if a language is in a given class, since satisfying the pumpinglemma is a necessary and sufficient necessary , but not sufficient, condition for class membership. References cite book author Michael Sipser year 1997 title Introduction to the Theory of Computation publisher PWS Publishing isbn 0 534 94728 X Section 1.4 Nonregular Languages, pp. 77&ndash 83. Section 2.3 Non contextfreeLanguages, pp. 115&ndash 119. cite book author Thomas A. Sudkamp year 2006 title Languages and Machines, Third edition publisher Adison Wesley isbn 0 321 32221 5 Chapter 6 Properties of Regular Languages pp. 205 210 Category Formal languages Category Lemmas bs Osobina napuhavanja cs Lemma o vkl d n de PumpingLemma es Lema del bombeo fr Lemme d it ration ko hr Svojstvo napuhavanja it Pumpinglemma nl Pompstelling ja pt Lema do bombeamento ro Lema de pompare ru sr uk zh ... more details
Contextfree may refer to Concepts contextfree grammar deterministic contextfree grammar stochastic contextfree grammar weighted contextfree grammar contextfree language Software ContextFree , a computer language for contextfree grammars disambig ... more details
n geq 0 math , which can be shown to be non contextfree by the pumpinglemma for contextfreelanguages . Contextfreelanguages are also not closed under complementation, as for any languages A and B ... free, one may employ the pumpinglemma for contextfreelanguages . Parsing Determining an instance ... . Also, most arithmetic expressions are generated by contextfree grammars. Closure properties Contextfreelanguages are closure mathematics closed under the following operations. That is, if L and P are contextfreelanguages, the following languages are contextfree as well the union set theory ... math vu uv in L math Contextfreelanguages are not closed under complement complexity complement ... math L cap D math and their difference math L setminus D math are contextfreelanguages. Nonclosure under intersection and complement The contextfreelanguages are not closed under intersection. This can ... are decidable for arbitrary contextfreelanguages is math L A emptyset math ? is math L A math ... freelanguages The reverse of a contextfree language is contextfree, but the complement need not be. Every ... . Formally, the set of all contextfreelanguages is identical to the set of languages accepted by pushdown ... contextfree language deterministic subclass of contextfreelanguages there are a number of well ... References cite book author Seymour Ginsburg title The Mathematical Theory of ContextFreeLanguages ... X Chapter 2 ContextFreeLanguages, pp. 91 122. Jean Michel Autebert, Jean Berstel, Luc Boasson, http www igm.univ mlv.fr berstel Articles 1997CFLPDA.pdf ContextFreeLanguages and Push Down Automata ...In formal language theory , a contextfree language is a formal language language generated by some contextfree grammar . The set of all contextfreelanguages is identical to the set of languages accepted by pushdown automaton pushdown automata . Examples An archetypical contextfree language is math ... freelanguages have many applications in programming languages for example, the Dyck language ... more details
is not regular language regular according to the PumpingLemma for regular languages . The special ... be found that generates the same contextfree language. However, there are certain languages that can ... languages and contextfreelanguages year 1982 last Pullum first Geoffrey K. coauthors Gerald Gazdar ... of ContextFreeLanguages, pp. 125 137. citation authorlink Michael Sipser first Michael last ... contextfreelanguages, pp. 156 159 Section 5.1.1 Reductions via computation histories pp. 176 183. Formal languages and grammars DEFAULTSORT ContextFree Grammar Category 1956 in computer ...refimprove date February 2012 In formal language theory , a contextfree grammar CFG is a formal grammar ... w can be empty . The formal language language s generated by contextfree grammars are known as the contextfree language s. Contextfree grammars are important in linguistics for describing ... use the term phrase structure grammar to refer to contextfree grammars, whereby phrase structure grammars ... . A contextfree grammar provides a simple and mathematically precise mechanism for describing the methods ... and reference are not part of the contextfree grammar, but the basic recursive structure of sentences ... and adverbs are swallowed by nouns and verbs, is described exactly. The formalism of contextfree ... of natural language was described by contextfree rules combined with transformation rules. Block structure ... project 1957 1960 , which, as a consequence, also featured a contextfree grammar to describe the resulting ... identified with contextfree grammar rules, especially in computer science. Formal constraints ... parser s are simpler algorithms that deal only with more restrictive subsets of contextfree grammars. Formal definitions A contextfree grammar G is defined by the 4 tuple ref The notation here ... u k Rightarrow v math Contextfree language The language of a grammar math G V ,, Sigma ,, R ,, S , math ... to be a contextfree language CFL , if there exists a CFG math G , math , such that math L , ,L G math ... more details
. The deterministic contextfreelanguages are exactly those recognized by some LR grammar . ref ... contextfreelanguages can be recognized by a deterministic Turing machine in polynomial ...A deterministic contextfree language is a formal language which is defined by a deterministic contextfree grammar . ref cite book last John Hopcroft Hopcroft first John coauthors Jeffrey Ullman title Introduction to automata theory, languages, and computation year 1979 publisher Addison Wesley page 233 ref The set of deterministic contextfreelanguages is called DCFL ref CZoo Class DCFL D dcfl ref and is identical to the set of languages accepted by a deterministic pushdown automaton . The set of deterministic contextfreelanguages is a proper subset of the set of contextfree language s that possess an unambiguous contextfree grammar . For example, the language of even length palindrome s on the alphabet of 0 and 1 has the simple, unambiguous grammar S 0S0 1S1 , but it cannot be parser parsed by a deterministic push down automaton. ref cite book last John Hopcroft Hopcroft first John coauthors Rajeev Motwani & Jeffrey Ullman title Introduction to automata theory, languages, and computation 2nd edition year 2001 publisher Addison Wesley pages 249 253 ref The languages of this class have practical importance in computer science. The complexity of the program and execution of a deterministic pushdown automaton is vastly less than that of a nondeterministic one. In the naive implementation ... algorithm to test membership in any contextfree language is CYK algorithm Extensions Valiant s algorithm , taking O n sup 2.378 sup time, whereas membership in a deterministic contextfree language ... s Greibach s theorem proves that it is undecidable whether a given contextfree language is deterministic References references Formal languages and grammars Category Formal languages comp sci ... to automata theory, languages, and computation 2nd edition year 2001 publisher Addison Wesley ... more details
In formal grammar theory, the deterministic contextfree grammars DCFGs are a proper subset of the contextfree grammars . The deterministic contextfree grammars are those a deterministic pushdown automaton can recognize. A DCFG is the finite set of rules defining the set of well formed expressions in some deterministic contextfree language . History In the 1960s, theoretic research in computer science on regular expressions and finite automata led to the discovery that contextfree grammars are equivalent to pushdown automata . These grammars were thought to capture the syntax of computer programming languages. The first computer programming languages were under development at the time see History of programming languages and writing compilers was difficult. But using contextfree grammars to help automate the parsing part of the compiler simplified the task. Deterministic contextfree grammars were particularly useful because they could be parsed sequentially, which was a requirement due to computer memory constraints. ref cite book editors A Salomaa & D Wood & S Yu title A Half Century of Automata Theory year 2001 publisher World Scientific Publishing Co. Pte. Ltd pages 38 39 ref Uses LALR parsers, which use a subset of DCFGs, have practical value as program code validators. Given the formal rules of a DCFG, these parsers efficiently ensure a program can be generated from those rules. In fact, this syntax validation is one of the operations a compiler performs. need to state the two restrictions for determinism, can t figure out how to express it simply Limitations Since DCFGs are a proper subset of CFGs, they are of less descriptive power than some CFGs. See also Deterministic parsing LR parser LL parser References references Formal languages and grammars Category Formal languages cs Deterministick bezkontextov gramatika hr Deterministi ka kontekstno neovisna gramatika sr zh ... more details
A weighted contextfree grammar WCFG is a contextfree grammar where each production has a numeric weight associated with it. The weight of a parse tree in a WCFG is the weight of the rule used to produce the top node, plus the weights of its children. A special case of WCFGs are stochastic contextfree grammar s, where the weights are logarithm s of probability probabilities . An extended version of the CYK algorithm can be used to find the lightest least weight derivation of a string given some WCFG. comp sci theory stub Category Formal languages hr Te inska kontekstno neovisna gramatika ja ru ... more details
than the class of LCFRSs as a whole. References references Formal languages and grammars DEFAULTSORT Generalized ContextFree Grammar Category Formal languages Category Grammar frameworks ...Generalized Contextfree Grammar GCFG is a grammar formalism that expands on contextfree grammars by adding potentially non contextfree composition functions to rewrite rules. ref name weir1988 Weir, David H. 1988. Characterizing mildly context sensitive grammar formalisms. Dissertation, U Penn. ref Head grammar and its weak equivalents is an instance of such a GCFG which is known to be especially adept at handling a wide variety of non CF properties of natural language. Description A GCFG consists of two components a set of composition functions that combine string tuples, and a set of rewrite rules. The composition functions all have the form math f langle x 1, ..., x m rangle, langle y 1, ..., y n rangle, ... gamma math , where math gamma math is either a single string tuple, or some use of a potentially different composition function which reduces to a string tuple. Rewrite rules look like math X to f Y, Z, ... math , where math Y math , math Z math , ... are string tuples or non terminal symbols. The rewrite semantics of GCFGs is fairly straight forward. An occurrence of a non terminal symbol is rewritten using rewrite rules as in a contextfree grammar, eventually yielding just compositions composition functions applied to string tuples or other compositions . The composition functions are then applied, reducing successively reducing the tuples to a single tuple. Example A simple translation of a contextfree grammar into a GCFG can be performed in the following fashion. Given the grammar in 1 , which generates the palindrome language math ww R w in a, b math , where ... rangle, langle a rangle math math langle abbbba rangle math Linear Contextfree Rewriting Systems LCFRSs ... and regular is called a Linear Contextfree Rewriting System LCFRS , a subset of the GCFGs with strictly ... more details
Synchronous contextfree grammars SynCFG or SCFG not to be confused with Stochastic contextfree grammar stochastic CFGs constitute a formal model of natural language syntax , developed in the area of statistical machine translation MT . The theory of SynCFGs borrows from syntax directed transduction and syntax based machine translation , modeling the reordering of clauses that occurs when translating a sentence by correspondences between phrase structure rules in the source and target languages. Performance of SCFG based MT systems has been found comparable with, or even better than, state of the art phrase based machine translation systems. ref name Chiang cite journal last1 Chiang first1 David year 2007 title Hierarchical phrase based translation journal Computational Linguistics journal Computational Linguistics volume 33 number 2 pages 201 228 ref Several algorithms exist to perform translation using SynCFGs. ref cite conference last1 Venugopal first1 Ashish last2 Zollmann first2 Andreas last3 Vogel first3 Stephan year 2007 title An efficient two pass approach to Synchronous CFG driven statistical MT booktitle Proc. NAACL HLT pages 500 507 ref Formalism Rules in a SynCFG are superficially similar to CFG rules, except that they specify the structure of two phrases at the same time one in the source language the language being translated and one in the target language. Numeric indices indicate correspondences between non terminals in both constituent trees. Chiang ref name Chiang gives the Chinese English example math X to math yu math X 1 math you math X 2 math , have math X 2 math with math X 1 math Software http cdec decoder.org cdec , MT decoding package that supports SynCFGs References references Category Formal languages Category Machine translation Category Natural language parsing Category Statistical natural language processing ... more details
Stochastic ContextFree Grammar Category Bioinformatics Category Formal languages Category Natural ...Weasel date June 2010 A stochastic contextfree grammar SCFG also probabilistic contextfree grammar , PCFG is a contextfree grammar in which each production is augmented with a probability. The probability of a derivation parse is then the product of the probabilities of the productions used in that derivation thus some derivations are more consistent with the stochastic grammar than others. SCFGs extend contextfree grammars in the same way that hidden Markov model s extend regular grammar s. SCFGs have application in areas as diverse as Natural language processing to the study of RNA molecules. SCFGs are a specialized form of weighted contextfree grammar s. Techniques A variant of the CYK algorithm finds the Viterbi algorithm Viterbi parse of a sequence for a given SCFG. The Viterbi parse is the most likely derivation parse of the sequence by the given SCFG. The Inside Outside algorithm is an analogue of the Forward backward algorithm Forward Backward algorithm , and can be used to compute ... language processing Contextfree grammars were originally conceived in an attempt to model natural languages, i.e. those normally spoken by humans. ref Noam Chomsky Syntactic Structures. Mouton & Co ... xpl freeabs all.jsp?arnumber 1566496 ref RNA Contextfree grammars are adept at modeling the secondary ... pairing can be represented in a contextfree grammar the major exception being pseudoknot s . For example ... languages . Probabilistic CFGs are an attempt to deal with difficulties encountered when attempting to extend CFGs to deal with the complexities of natural languages. Specifically, one often finds that more .... As such, a probabilistic grammar s validity is constrained by context of the text used to train it the definition of most likely is likely to vary with the context of discourse. An example of a probabilistic ... that grammars for natural languages governed by deterministic rules could not be learned based on positive ... more details
In the theory of formal language s, Ogden s lemma named after William F. Ogden provides an extension of flexibility over the pumpinglemma for contextfreelanguages . Ogden s lemma states that if a language L is contextfree, then there exists some number p 0 where p may or may not be a pumping length such that for any string w of length at least p in L and every way of marking p or more of the positions in w , w can be written as w uxyzv with strings u , x , y , z , and v , such that xz has at least one marked position, xyz has at most p marked positions, and ux sup i sup yz sup i sup v is in L for every i &ge 0. Ogden s lemma can be used to show that certain languages are not contextfree, in cases where the pumpinglemma for contextfreelanguages is not sufficient. An example is the language a sup i sup b sup j sup c sup k sup d sup l sup i 0 or j k l . It is also useful to prove the Ambiguous grammar Inherently ambiguous languages inherent ambiguity of some languages. Observe that when every position is marked, this lemma is equivalent to the pumpinglemma for contextfreelanguages. See also Pumpinglemma for contextfreelanguagesPumpinglemma for regular languages References cite journal author Ogden, W. title A helpful result for proving inherent ambiguity journal Mathematical Systems Theory volume 2 year 1968 pages 191 194 doi 10.1007 BF01694004 issue 3 cite book author Hopcroft, Motwani and Ullman year 1979 title Automata Theory, Languages, and Computation publisher Addison Wesley isbn 8178083477 Category Formal languages Category Lemmas de Ogdens Lemma fr Lemme d Ogden hr Ogdenova lema it Lemma di Ogden ja pl Lemat Ogdena pt Lema de Ogden ru zh ... more details
wiktionary pumpingPumping can refer to The operation of a pump , for moving a liquid from one location to another The use of a breast pump or milking machine for extraction of milk Gastric lavage The process of cleaning the contents of the stomach Pumping oil well , injecting chemicals into a wellbore Pumping computer systems , the number of times data is transmitted per clock cycle Pump skateboarding , a process by which longboard skateboarders accelerate without pushing off of the ground Pumpinglemma in the theory of formal languages An artifact of audio dynamic range compression Optical pumping , a process in which light is used to raise electrons from a lower energy level in an atom or molecule to a higher one Weight training pumping iron building muscle by exercising with weights Sexual intercourse Pumping My Heart , a song by Patti Smith Group See also Pump disambig es Bombeo de Pumpen ... more details
ConTeXt is free software the program code i.e. anything not under the code doc code subtree is distributed ... output EN.svg center 600px ConTeXt document See also Portal Free software LaTeX TeX References Reflist ... gather, split, etc. . TeX navbox DEFAULTSORT Context Category Page description languages Category Free TeX software de ConTeXt es ConTeXt fr ConTeXt hr ConTeXt ja ConTeXt pl ConTeXt sl ConTEXt ...Distinguish ConTEXT Infobox software name ConTeXt logo Image ConTeXt Unofficial Logo.svg The Unofficial ConTeXt logo contextgarden.net logo 200px author Mainly Hans Hagen and http www.pragma ade.com Pragma ... of ConTeXt at contextgarden ref ref http foundry.supelec.fr frs ?group id 14 List of releases of ConTeXt ref ref http foundry.supelec.fr gf project contextrev frs ConTeXt files in Supelec ref operating ... licenses by nc sa 3.0 CC BY NC SA 3.0 ref http wiki.contextgarden.net Read Me Read Me license of ConTeXt code and documentation ref website http wiki.contextgarden.net contextgarden ConTeXt is a general ... and automated capabilities of ConTeXt are extensive, including interfaces for handling microtypography ... it easy to create new layouts and styles without learning the low level TeX macro language. ConTeXt may be compared and contrasted with LaTeX , but the primary thrust of the two are rather distinct. ConTeXt ... time, ConTeXt s unified design avoids the package clashes that can happen with LaTeX. ref http www.tex.ac.uk cgi bin texfaq2html?label context FAQ of the UK TeX Archive ref ref name whatiscontextwiki http wiki.contextgarden.net What is ConTeXt What is ConTeXt page at contextgarden ref ConTeXt ..., and Italian and support for output in many languages including western European, eastern European ... native drawing engine, ConTeXt integrates a superset of MetaPost called MetaFun ref name whatiscontextwiki .... Metafun can also be used with stand alone MetaPost. ConTeXt also supports the use of other ... generic pgf pgfmanual.pdf PGF TikZ official manual. Version 2.0 . Section 9.1.3 Using the ConTeXt Format ... more details
distinguish ConTeXt Infobox Software name ConTEXT logo Image ConTEXT Logo.png screenshot Image ConTEXT 0.98.3.png 250px caption ConTEXT v0.98.6 developer ConTEXT Project released ? frequently updated yes Release version update? Don t edit this page, just click on the version number programming language Delphi programming language Delphi operating system Microsoft Windows language english german genre Text editor license New BSD License citation needed date October 2011 website http www.contexteditor.org www.contexteditor.org ConTEXT is a text editor for Microsoft Windows that can open and edit very large files, while requiring only modest amounts of RAM and hard drive space to run. It has built in Syntax highlighting syntax highlighters for C programming language C C , Delphi programming language Delphi Pascal programming language Pascal , FORTRAN , 80x86 assembler, Java programming language Java , JavaScript , Visual Basic , Perl Common Gateway Interface CGI , HTML , SQL , Python programming language Python , PHP , Tcl Tk , and its own syntax highlighter definition language. Other features ... Interface . ConTEXT can integrate compiler s to compile source code from within the editor, and run ... search and basic regular expressions are supported for searching and replacing. ConTEXT is available in many languages. On 7 September 2007 the creator of ConTEXT announced he wanted to sell the project including the full source, copyrights, website and domain. ref http www.contexteditor.org ConTEXT ... project was bought and ConTEXT Project was set up as a company. citation needed date October 2011 In March 2009 the decision was made to make ConTEXT open source. citation needed date October ... www.contexteditor.org Freeware Text Editor http www.contexteditor.org downloads ConTEXT Downloads Category Windows text editors Category Windows only freeware Windows software stub fr ConTEXT it ConTEXT hu ConTEXT nl ConTEXT pl ConTEXT fi ConTEXT ... more details
Wiktionary Wikipedia Books ContextContext may refer to Context language use , the relevant constraints of the communicative situation that influence language use, language variation, and discourse summary Archaeological context , an event in time which has been preserved in the archaeological record Opaque context , linguistic context in which substitution of co referential expressions does not preserve truth Trama mycology context or flesh , the mass of non hymenial tissues that composes the mass of a fungal fruiting body Computing Context computing , the virtual environment required to suspend a running software program Context awareness , a complementary to location awareness Context menu , a menu in a graphical user interface that appears upon user interaction ConTeXt , a macro package for the TeX typesetting system ConTEXT , a text editor for Microsoft Windows Operational context , a temporarily defined environment of cooperation See also lookfrom intitle Contextual disambiguation Contextualization disambiguation Locality disambiguation State disambiguation disambig de Kontext es Contexto fr Contexte nl Context simple Context sk Kontext ... more details
Lemma may refer to wiktionary Lemma mathematics , a proven statement used as a stepping stone toward the proof of another statement Lemma morphology , the canonical form or citation form of a word Lemma psycholinguistics , an intermediate form a word about to be uttered takes during speech production Headword , in lexicons Lemma logic , which is simultaneously a premise for a contention above it and a contention for premises below it Lemma botany , one of the specialised bracts enclosing a floret in a grass inflorescence Misspellings Analemma , the curve traced out by a celestial body over the course of a year on the celestial sphere of another body a phenomenon that may be used to determine the time of year Morris Iemma Note spelling with a capital i , former premier of the Australian state of New South Wales disambig cs Lemma da Lemma de Lemma el fr Lemme io Lemo id Lemma it Lemma lb Lemma nl Lemma simple Lemma ... more details
of a context sensitive language that is not contextfree is L a sup p sup p is a prime number . L can be shown to be a context sensitive language by constructing a linear bounded automaton which accepts L . The language can easily be shown to be neither regular language regular nor contextfree language contextfree by applying the respective pumpinglemma s for each of the language classes to L . An example of recursive language that is not context sensitive is any recursive language whose decision .... Properties of context sensitive languages The union, intersection, concatenation and kleene star of two context sensitive languages is context sensitive. The complement of a context sensitive language is itself context sensitive. Every contextfree grammar contextfree language is context sensitive. Membership of a string in a language defined by an arbitrary context sensitive grammar, or by an arbitrary deterministic context sensitive grammar, is a PSPACE complete problem. See also Linear bounded automaton Chomsky hierarchy Noncontracting grammar s generate exactly the context sensitive languages Indexed language s a strict subset of the context sensitive languages References ... pub space.pdf Formal languages and grammars DEFAULTSORT Context Sensitive Language Category Formal languages ar bs Kontekstno zavisni jezik cs Kontextov jazyk de Kontextsensitive Sprache ...In theoretical computer science , a context sensitive language is a formal language that can be defined by a context sensitive grammar . That is one of the four types of grammars in the Chomsky hierarchy ... Computationally, a context sensitive language is equivalent with a linear bounded nondeterministic .... This means that every formal language that can be decided by such a machine is a context sensitive language, and every context sensitive language can be decided by such a machine. This set of languages is also known as NLIN SPACE , because they can be accepted using linear space on a non ... more details
Mild context sensitivity is defined in terms of sets of languages. A set of languages is mildly context sensitive if and only if it contains all Contextfree language contextfreelanguages , it admits limited Cross serial dependency cross serial dependencies , all the languages are parsable in polynomial time , and all the languages have constant growth this means that the distribution ... lemma for some class of mildly context sensitive languages. Formalisms Some attempts at creating mildly context sensitive language formalisms include Generalized contextfree grammar Linear Contextfree Rewriting Systems .28LCFRSs.29 Linear contextfree rewriting system s developed by D. J. Weir ...In formal grammar theory, mildly context sensitive languages are a class of formal languages which can be efficiently parsed, but still possess enough context sensitive language context sensitivity to allow ... tree adjoining grammars defined in ref Joshi, et. al, 1991 ref . Multiple contextfree grammar s, developed ... contextfree grammars, multiple contextfree grammars, and head grammars journal Technical Report, Department ... Hierarchy A more precisely defined hierarchy of languages that correspond to the mildly context sensitive ... as contextfree, and Level 2 is the class of tree adjoining and the other three grammars. Following ... 1 to the conditions of mildly context sensitive languages imposed by Joshi, and as k gets bigger ... of Four Extensions of ContextFree Grammars year 1994 journal Mathematical Systems Theory volume ... Context Sensitive Languages with Thread Automata year 2002 title Proceedings of the 19th international ... pages 1 7 . Citation last Weir first D. J. year 1992 title A geometric hierarchy beyond contextfree ... ContextFree Grammar, by Laura Kallmeyer http www.sfb441.uni tuebingen.de lk TAG SEMINAR Seminar on tree adjoining grammars and mildly context sensitive languages and formalisms, by Laura Kallmeyer http www.kornai.com MatLing mcsfin.pdf Mildly Context Sensitive Grammars, by Aravind Joshi Formal languages ... more details
, for example, run , runs , ran and running are forms of the same lexeme , with run as the lemma. Lexeme , in this context, refers to the set of all the forms that have the same meaning, and lemma ...In morphology linguistics morphology and lexicography , a lemma plural lemmas or lemmata is the canonical ... significance in highly inflection inflected languages such as Turkish language Turkish and Czech language Czech . The process of determining the lemma for a given word is called lemmatisation . Morphology ... form uses a form of the indefinite pronoun one e.g., do one s best , perjure oneself . In languages ... the masculine singular nominative. In many languages, the citation form of a verb is the infinitive ... of Irish initial mutations initial mutations . The noun cainteoir , the lemma for the noun ... , chainteoir and gcainteoir . Some phrases are cited in a sort of lemma, e.g., Carthago delenda ... must be destroyed . Lexicography In a dictionary, the lemma go represents the Inflection inflected ... lemma is usually denoted by an angle bracket, e.g., went go . The disadvantage of such simplifications ... does. The form that is chosen to be the lemma is usually the least markedness marked form, though ... of lemma is flexible depending on the task it is being used for. Difference between stem and lemma ... morphologically inflected, whilst a lemma is the base form of the verb. For example, from produced , the lemma is produce , but the stem is produc . This is because there are words such as produc tion ... IPA . Some lexemes have several stems but one lemma. For instance to go the lemma has the stems ... Wiktionary Lemmas http torvald.aksis.uib.no corpora 1999 4 0038.html Lemma vs lexeme Lexicography Category Lexical units Category Units of linguistic morphology ar br Lemma yezhoniezh cs Lemma lingvistika da Lemma leksikografi de Lemma Lexikografie eo Kapvorto es Lema ling stica fr Lemme linguistique hr Lema rje ni ka natuknica id Lema linguistik it Lemma linguistica lb Lemma Lexikographie ... more details
Unreferenced date July 2007 Sewage pumping is normally done by a submersible pump . This became popular in the early 1960s, when a guide rail system was developed to lift the submersible pump out of the pump station for repair, and ended the dirty and sometimes dangerous task of sending people into the sewage or wet pit. Growth of the submersible pump for sewage pumping since has been dramatic, as an increasing number of specifiers and developers learned of their advantages. Three classes of submersible pumps exist Smaller submersible pumps, used in domestic and light commercial applications, normally handle up to 55mm spherical solids and range from 0.75 kW to 2.2 kW. Larger submersible pumps, handle 65mm and larger solids and normally have a minimum of 80mm discharge. They are generally used in municipal and industrial applications for pumping sewage and all types of industrial wastewater. Submersible chopper pumps , which are used to handle larger concentrations of solids and or tougher solids that conventional sewage pumps cannot handle. Chopper pumps are generally used in municipal and industrial wastewater applications and provide clog free operation by maceration sewage macerating those solids that might clog other types of submersible pumps. Submersible pumps are normally used in a packaged pump station where drainage by gravity is not possible. Vertical type sewage pumps have also been used for many years. They have the motor above the floor so work on the motor can be done without entering the sewage pit. See also Sewage treatment Pumping station Packaged pump station Submersible pump Chopper pumps Literature D. Weismann, T. Gutzeit Kommunale Abwasserpumpwerke. 2nd edition, VULKAN Verlag, Germany 2006, ISBN 978 3 8027 2843 3 D. Weismann, M. Lohse Sulfid Praxishandbuch der Abwassertechnik Geruch, Gefahr, Korrosion verhindern und Kosten beherrschen 1st edition, VULKAN Verlag, Germany 2007, ISBN 978 3 8027 2845 7 DEFAULTSORT Sewage Pumping Category Sewerage ... more details
Multiple issues wikify May 2012 orphan May 2012 notability May 2012 unreliable sources May 2012 Female pumping is a sexual activity that involves the use of a vacuum device primarily over the female genitals and non genital areas like the breast s and nipple s. As well as other parts of the body, with the intention of making body tissues swell and increase in size temporarily. Some women like the feeling it gives them when their genital tissues are swollen, providing form heightened sensitivity to the genital region by having all the vulva tissues engorged with blood. Origins Female pumping had its origins back in 1996, as women wanted to learn more about the benefits and effects vacuum pumping would have on a woman s body. Some documents where published on the Internet about the activity by G.Dolby about the practice. These documents discussed the placing of a vacuum device over their clitoris and vulva to experience what suction feels like on female genitals. A small site was created four years later in September 2000, providing information about female pumping and where women could post information about their pumping experiences and to learn more about the pumping process. As time has passed, the activity of female pumping has gained great popularity around the world. Types of Female Pumping Female pumping is the main term used to describe all the different types of vacuum pumping that women perform according to the origins of the activity. The main types of female pumping practiced involve, clitoral pumping, vulva pumping, breast pumping, nipple pumping and to some extent Anus anal pumping. The focus of these areas is that it providing sexual pleasure when a woman is performing female pumping. Uncategorized date May 2012 ... more details
Context sensitive is an adjective meaning depending on context or depending on circumstances . It may refer to Context sensitive grammar Context sensitive language Context sensitive help Context sensitive user interface in computing Disambiguation ... more details
In computer science, a task context process computing process , thread computer science thread ... is the minimal set of data used by this task that must be saved to allow a task interrupt ion at a given date, and a continuation of this task at the point it has been interrupted and at an arbitrary future date. The concept of context assumes significance in the case of interruptible tasks, wherein upon being interrupted the processor saves the context and proceeds to serve the Interrupt service routine . Thus the smaller the context the smaller is the latency. These data are located in Processor registers Memory used by the task On some Operating systems , control registers used by the system to manage the task The storage memory files is not concerned by the task context in the case of a context switch even if this can be stored for some uses checkpointing . Context types In some computer languages like C , there is also the concept of safe secure context . For instance, if an Array data type array is needed inside a struct C programming language structure , it can be added to it since version 2.0, but only in an unsafe unsecure context. ref http en.wikibooks.org wiki C Sharp Programming Classes Structures Structures in C 2.0 ref Here is an example code source lang CSharp struct ParameterRepresentation char target char taskStart char taskType fixed byte traceValues m MAX BYTES source The http en.wikibooks.org wiki C Sharp Programming Keywords fixed fixed keyword prevents the Garbage collector computing garbage collector from relocating this variable. The access to an array is like in C , i.e. using pointer arithmetic, where individual elements of the array can be accessed ... article view 04099921013 1431 Context and Adaptivity in Pervasive Computing Environments Links with Software ... cube network.eu km terms c contextContext S Cube Knowledge Model Categories DEFAULTSORT Context ... d ex cution pt Contexto computa o simple Context computing ... more details
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