Constraint Answer Set Programming Based on HEX-Programs
نویسندگان
چکیده
Constraint Answer Set Programming (CASP) is a convenient integration of the Answer Set Programming (ASP) paradigm with constraint programming (CP), which was exploited for a range of applications. HEX-programs are another extension of ASP towards integration of arbitrary external sources through socalled external atoms. In this work, we integrate HEX-programs with CP, which results in a strict generalization of CASP, called constraint HEX-programs. We then present a translation of constraint HEX-programs to (standard) HEX-programs using special external sources for constraint solving. In contrast to native CASP solvers, this not only allows for reusing existing algorithms, but also for combining constraints with other external sources. We further show how to integrate advanced techniques used in CASP solving algorithms; while dedicated solvers are currently faster as not all such techniques have been integrated yet, our experiments show that this significantly improves efficiency and promises that further optimization integrated in future work will yield an efficient yet more general system.
منابع مشابه
On Equivalence and Inconsistency of Answer Set Programs with External Sources
HEX-programs extend of answer-set programs (ASP) with external sources. In previous work, notions of equivalence of ASP programs under extensions have been developed. Most well-known are strong equivalence, which is given for programs P and Q if P ∪ R and Q ∪ R have the same answer sets for arbitrary programs R, and uniform equivalence, which is given if this is guaranteed for sets R of facts. ...
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