A Parsing Method for Context‐Sensitive C‐Plex Grammars Using Logic Programming

Abstract

AbstractThe high‐dimensional grammars, such as Plex grammar and graph grammar, have strong descriptive powers, but have a problem in that the parsing algorithm is difficult. To apply those grammars to the pattern analysis and recognition, it is desirable that the parsing method for those grammars should be established. As a method toward the parsing of Plex grammar, the authors previously have proposed a C‐Plex grammar and a parsing method for the context‐free C‐Plex grammar, based on the logic programming of Prolog. Further, a parsing method is presented for context‐sensitive C‐Plex grammar based on the logic programming.First, a parsing algorithm is proposed which realizes the pseudo‐leftmost derivation in context‐sensitive C‐Plex grammar. Then, to arrive at a Horn clause program executing the parsing algorithm, a general rewriting method from the context‐sensitive C‐plex grammar to Horn clause is presented. Using the circuit pattern as an example, the result of parsing is shown. The description of rules by predicate logic expression and the parsing method based on logic language Prolog characterize the C‐Plex grammar as a kind of logic grammar. C‐Plex grammar can be applied not only to the grammatical pattern analysis and recognition but also to the parsing processing in the intelligent system such as pattern interpretation as a logic grammar.