Survey
* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project
Download flight - clic
Document related concepts
Morphology (linguistics) wikipedia , lookup
Kannada grammar wikipedia , lookup
Old Irish grammar wikipedia , lookup
Antisymmetry wikipedia , lookup
Probabilistic context-free grammar wikipedia , lookup
Dependency grammar wikipedia , lookup
French grammar wikipedia , lookup
Agglutination wikipedia , lookup
Serbo-Croatian grammar wikipedia , lookup
Georgian grammar wikipedia , lookup
Lexical semantics wikipedia , lookup
Arabic grammar wikipedia , lookup
Chinese grammar wikipedia , lookup
Zulu grammar wikipedia , lookup
Compound (linguistics) wikipedia , lookup
Spanish grammar wikipedia , lookup
Polish grammar wikipedia , lookup
Ancient Greek grammar wikipedia , lookup
Portuguese grammar wikipedia , lookup
Context-free grammar wikipedia , lookup
Junction Grammar wikipedia , lookup
Scottish Gaelic grammar wikipedia , lookup
Transformational grammar wikipedia , lookup
Latin syntax wikipedia , lookup
Turkish grammar wikipedia , lookup
Vietnamese grammar wikipedia , lookup
Malay grammar wikipedia , lookup
Determiner phrase wikipedia , lookup
Yiddish grammar wikipedia , lookup
Transcript
Defining a CF language via derivation
â¢
A string A derives a string B if
â
â¢
A can be rewritten as B via some series of rule applications
More formally:
â
â
â
If A -> ï¢ is a production of P
ï¡ and ï§ are any strings in the set (ï ï N)*
Then we say that
â¢
â
â
Derivation is a generalization of direct derivation
Let ï¡1, ï¡2, ⦠ï¡m be strings in (ï ï N)*, m>= 1, s.t.
â¢
â¢
â
ï¡Aï§ directly derives ï¡ï¢ï§ or ï¡Aï§ ï ï¡ï¢ï§
ï¡1ï ï¡2, ï¡2ï ï¡3⦠ï¡m-1ï ï¡m
We say that ï¡1derives ï¡m or ï¡1*ï ï¡m
We then formally define language LG generated by grammar G
â¢
â¢
A set of strings composed of terminal symbols derived from S
LG = {w | w is in ï* and S *ï w}
