2015/07/11 by Thomas Eiter, Michael Fink, Giovambattista Ianni +3
Computer Science · #Answer set programming #Computation #Computer science #Database #Distributed computing #Flexibility (engineering) #Generalization #Graph #Interface (matter) #Interleaving #Logic, Reasoning, and Knowledge #Logic, programming, and type systems #Multi-Agent Systems and Negotiation #Operating system #Parallel computing #Programming language #Rotation formalisms in three dimensions #Scalability #Set (abstract data type) #Software #Theoretical computer science #acm:68T27 #acm:68T30 #cs.AI #cs.LO #cs.PL #msc:68T27 #msc:68T30
paper · pdf · doi:10.1017/s1471068415000113
published as Theory and Practice of Logic Programming 16 (2016) 418-464 · 57 pages, 9 figures, 3 tables, 6 algorithms, to appear in Theory and Practice of Logic Programming (accepted in June 2015)
arxiv created 2015/07/11 · openalex publication_date 2015/08/13 · arxiv updated 2020/02/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Abstract As software systems are getting increasingly connected, there is a need for equipping nonmonotonic logic programs with access to external sources that are possibly remote and may contain information in heterogeneous formats. To cater for this need, hex programs were designed as a generalization of answer set programs with an API style interface that allows to access arbitrary external sources, providing great flexibility. Efficient evaluation of such programs however is challenging, and it requires to interleave external computation and model building; to decide when to switch between these tasks is difficult, and existing approaches have limited scalability in many real-world application scenarios. We present a new approach for the evaluation of logic programs with external source access, which is based on a configurable framework for dividing the non-ground program into possibly overlapping smaller parts called evaluation units. The latter will be processed by interleaving external evaluation and model building using an evaluation graph and a model graph, respectively, and by combining intermediate results. Experiments with our prototype implementation show a significant improvement compared to previous approaches. While designed for hex -programs, the new evaluation approach may be deployed to related rule-based formalisms as well.