Soft constraint propagation and solving in CHRs

Soft constraints are a generalization of classical constraints, where constraints and/or partial assignments are associated to preference or importance levels, and constraints are combined according to combinators which express the desired optimization criteria. Constraint Handling Rules (CHRs) constitute a high-level natural formalism to specify constraint solvers and propagation algorithms. In this paper we present a framework to design and specify soft constraint solvers by using CHRs. In this way, we extend the range of applicability of CHRs to soft constraints rather than just classical ones, and we provide a straightforward implementation for soft constraint solvers. Keywords Constraint reasoning algorithms, constraint programming

• Type: Journal
• Year: 2002
• Where: SAC
• Authors: Stefano Bistarelli, Thom W. Frühwirth, Michael Marte
• Keywords: Applied Computing, Constraint Solvers, SAC 2002, Soft Constraint, Soft Constraint Solvers