Strong Equivalence and Program Structure in Arguing Essential Equivalence between Logic Programs
This work addresses the challenge of ensuring essential equivalence between logic programs in answer set programming, which is incremental as it builds on existing formal methods for program analysis.
The paper tackles the problem of formally linking different answer set programs for the same problem, which can have varying performance, by presenting formal results on program rewritings and proving the correctness of the Projector system for automatic rewritings to improve efficiency.
Answer set programming is a prominent declarative programming paradigm used in formulating combinatorial search problems and implementing different knowledge representation formalisms. Frequently, several related and yet substantially different answer set programs exist for a given problem. Sometimes these encodings may display significantly different performance. Uncovering precise formal links between these programs is often important and yet far from trivial. This paper presents formal results carefully relating a number of interesting program rewritings. It also provides the proof of correctness of system Projector concerned with automatic program rewritings for the sake of efficiency. Under consideration in Theory and Practice of Logic Programming (TPLP).