Incorporating Molecular Evolution into a search for Stochastic Context-Free Grammars
نویسنده
چکیده
A context-free grammar G (henceforth abbreviated to “grammar”) is a 4-tuple (N,V, P, S) consisting of the following components: a finite set N of non-terminal variables, a finite set V of terminal variables that is disjoint from N , a finite set P of production rules, mapping non-terminal variables to a series of non-terminals and terminals, and a distinguished symbol S ∈ N that is the start symbol. Beginning with the start symbol, following production rules, a ‘string’ of terminal variables is produced (if this exists). A grammar might be represented as follows.
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