Computing Loops with at Most One External Support Rule for Disjunctive Logic Programs

Authors:
Xiaoping Chen;Jianmin Ji;Fangzhen Lin
Affiliations:
School of Computer Science and Technology, University of Science and Technology of China, P.R. China;School of Computer Science and Technology, University of Science and Technology of China, P.R. China;Department of Computer Science and Engineering, Hong Kong University of Science and Technology,
Venue:
ICLP '09 Proceedings of the 25th International Conference on Logic Programming
Year:
2009

Citing 9
Cited 4

The alternating fixpoint of logic programs with negation

PODS '89 Proceedings of the eighth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Disjunctive stable models: unfounded sets, fixpoint semantics, and computation

Information and Computation
Nested expressions in logic programs

Annals of Mathematics and Artificial Intelligence
ASSAT: computing answer sets of a logic program by SAT solvers

Artificial Intelligence - Special issue on nonmonotonic reasoning
Comparisons and computation of well-founded semantics for disjunctive logic programs

ACM Transactions on Computational Logic (TOCL)
The DLV system for knowledge representation and reasoning

ACM Transactions on Computational Logic (TOCL)
Answer Set Programming Based on Propositional Satisfiability

Journal of Automated Reasoning
Discovering classes of strongly equivalent logic programs

Journal of Artificial Intelligence Research
A model-theoretic counterpart of loop formulas

IJCAI'05 Proceedings of the 19th international joint conference on Artificial intelligence

First-Order encodings for modular nonmonotonic datalog programs

Datalog'10 Proceedings of the First international conference on Datalog Reloaded
Conflict-driven answer set solving: From theory to practice

Artificial Intelligence
Computing Loops with at Most One External Support Rule
Tableau Calculi for Logic Programs under Answer Set Semantics

ACM Transactions on Computational Logic (TOCL)

Quantified Score

Hi-index	0.00

Visualization

Abstract

We extend to disjunctive logic programs our previous work on computing loop formulas of loops with at most one external support. We show that for these logic programs, loop formulas of loops with no external support can be computed in polynomial time, and if the given program has no constraints, an iterative procedure based on these formulas, the program completion, and unit propagation computes the least fixed point of a simplification operator used by DLV. We also relate loops with no external supports to the unfounded sets and the well-founded semantics of disjunctive logic programs by Wang and Zhou. However, the problem of computing loop formulas of loops with at most one external support rule is NP-hard for disjunctive logic programs. We thus propose a polynomial algorithm for computing some of these loop formulas, and show experimentally that this polynomial approximation algorithm can be effective in practice.