context-free — adjective a) (Of a grammar) which generates sentences in stages, in such a way that at any intermediate stage, any piece of the sentence is enough to determine the corresponding piece at the next stage; that is, the stagewise transformation at a… … Wiktionary
Context-free grammar generation algorithms — are algorithms which generate a context free grammar or grammars from given symbol sequence or sequences.Applications for such algorithms include lossless data compression and data mining. A list of algorithms * Sequitur * Lempel Ziv Welch… … Wikipedia
Context-free grammar — In formal language theory, a context free grammar (CFG) is a formal grammar in which every production rule is of the form V → w where V is a single nonterminal symbol, and w is a string of terminals and/or nonterminals (w can be empty). The… … Wikipedia
Context-free language — In formal language theory, a context free language is a language generated by some context free grammar. The set of all context free languages is identical to the set of languages accepted by pushdown automata. Contents 1 Examples 2 Closure… … Wikipedia
context-free — adjective Date: 1964 of, relating to, or being a grammar or language based on rules that describe a change in a string without reference to elements outside of the string; also being such a rule … New Collegiate Dictionary
context-free — ˈ ̷ ̷ ˌ ̷ ̷ ¦ ̷ ̷ adjective : of, relating to, or being a grammar or language based on rules that describe a change in a string without reference to elements outside of the string ; also : being such a rule … Useful english dictionary
Pumping lemma for context-free languages — The pumping lemma for context free languages, also known as the Bar Hillel lemma, is a lemma that gives a property that all context free languages have. Its primary use is to prove a language is not context free.The pumping lemma for context free … Wikipedia
Deterministic context-free language — A deterministic context free language is a formal language which is defined by a deterministic context free grammar.[1] The set of deterministic context free languages is called DCFL[2] and is identical to the set of languages accepted by a… … Wikipedia
Deterministic context-free grammar — In formal grammar theory, the deterministic context free grammars (DCFGs) are a proper subset of the context free grammars. The deterministic context free grammars are those a deterministic pushdown automaton can recognize. A DCFG is the finite… … Wikipedia
Stochastic context-free grammar — A stochastic context free grammar (SCFG; also probabilistic context free grammar, PCFG) is a context free grammar in which each production is augmented with a probability. The probability of a derivation (parse) is then the product of the… … Wikipedia