(15) Hierarchical Constraint Logic Programming Language: CHAL

	Machine:     PSI
	Environment: SIMPOS
	Language:    ESP
	Source Code: 61 KB
	Documents:   None

Overview

A hierarchical constraint logic programming language processor which introduces hierarchy in terms of strength of constraints.

Function

Hierarchical constraint logic programming language CHAL is based on new programming paradigm "constraint programming" which allows user a high-level description in problem solving. CHAL consists of constraint hierarchy solver which manipulates various strength of constraints in various domains and constraint language processor. User can make a program of his problem without worrying about solving method.

An Extension of Constraint Logic Programming Language
Usual constraint logic programming languages output nothing if there is no solution for given constraints. On the other hand, by introducing hierarchy of strength in constraints, CHAL ignores some weak constraints in order to output some better solutions.
This function is important in planning and design problems.
Constraints Solvers for Various Domains
CHAL provides the following constraint solvers for various domains of users:
  1. non-linear algebraic equations,
  2. Boolean equations.
User can specify various strength for these constraints.

Reference

  1. Satoh, K., "Formalizing Soft Constraints by Interpretation Ordering", Proceedings of the Ninth European Conference on Artificial Intelligence, pp.585-590, Stockholm, Sweden(1990).
  2. Satoh, K.and Aiba, A., Computing Soft Constraints by Hierarchical Constraint Logic Programming, ICOT-TR-610, ICOT, Japan(1990).

FTP

www-admin@icot.or.jp