Preprocessing of Complex Non-Ground Rules in Answer Set Programming

Michael Morak & Stefan Woltran
In this paper we present a novel method for preprocessing complex non-ground rules in answer set programming (ASP). Using a well-known result from the area of conjunctive query evaluation, we apply hypertree decomposition to ASP rules in order to make the structure of rules more explicit to grounders. In particular, the decomposition of rules reduces the number of variables per rule, while on the other hand, additional predicates are required to link the decomposed rules...