Relaxation in Constraint Logic Languages
Kannan Govindarajan, Bharat Jayaraman, Surya Mantha · The MIT Press eBooks · 1995
Optimization and relaxation are two important operations that naturally arise in many applications requiring the use of constraints, e.g., engineering design, scheduling, decision support, etc. In optimization, we are interested in finding the optimal solutions to a set of constraints with respect to an objective function. In many applications, optimal solutions may be difficult or impossible to obtain, and hence we are interested in finding suboptimal solutions, by either relaxing the constraints or relaxing the objective function. The contribution of this paper lies in providing a logical framework for performing optimization and relaxation in a constraint logic programming language. Our proposed framework is called preference logic programming (PLP), and its use for optimization was discussed in [4]. Essentially, in PLP we can designate certain predicates as optimization predicates, and we can specify the objective function by stating preference criteria for determing the optimal so...