DP — A System for Reasoning with Supernormal Defaults
نویسنده
چکیده
DP is a top-down theorem prover for supernormal or Poole-type defaults. Axioms and defaults can be arbitrary clauses, i.e. it supports disjunctions and (real) classical negation. Multiple disjunctions can be handled credulously, skeptically, and carefully. In skeptical mode, the expressivity of supernormal defaults corresponds to variable circumscription. The system is based on model elimination, implemented in a way very similar to Prolog interpreters. It is quite efficient in comparison with meta-interpreters. DP is freely avialable via ftp (currently only in binary form). Version 0.3 is still limited with respect to the type system and the user interface, but it is at least sufficent for classroom demonstrations. We plan to further develop DP to make it a powerful tool for real applications.
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تاریخ انتشار 1995