Conditional Symmetry Breaking
نویسندگان
چکیده
We introduce the study of Conditional symmetry breaking in constraint programming. This arises in a sub-problem of a constraint satisfaction problem, where the sub-problem satisfies some condition under which additional symetries hold. Conditional symmetry can cause redundancy in a systematic search for solutions. Breaking this symmetry is an important part of solving a constraint satisfaction problem effectively. We demonstrate with implementation results that three methods well known for breaking unconditional symmetries, can be applied to conditional symmetries. These are adding conditional symmetry-breaking constraints, reformulating the problem to remove the symmetry, and augmenting the search process to break the conditional symmetry dynamically through the use of a variant of SBDD.
منابع مشابه
Approaches to Conditional Symmetry Breaking
Conditional symmetry arises in a sub-problem of a constraint satisfaction problem, where the sub-problem satisfies some condition under which additional symetries hold. Typically, the condition is a set of assignments of values to variables, i.e. a partial assignment reached during systematic search. Like unconditional symmetry, conditional symmetry can cause redundancy in a systematic search f...
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