Local Consistency for Ternary Numeric Constraints
نویسندگان
چکیده
We consider algorithms of the Waltz type for computing local consistency (also called arc-consistency) for constraints over numeric domains. Many commonly used propagation rules do not in fact enforce local consistency. We extend the propagation rule given by Falt-ings Faltings, 1994] to the case of ternary constraints. Since any general n-ary continuous constraint can be represented as a collection of ternary ones, this also covers n-ary constraints in general. We show how the propagation can be implemented eeciently. The new algorithm gives signiicantly tighter labellings than previous propagation algorithms on most problems.
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