Reducing Symmetry in Matrix Models: SBDS v. Constraints
نویسنده
چکیده
We discuss diierent methods of reducing symmetry in CSPs where the variables correspond to the cells of a matrix, and both the rows and the columns of the matrix are interchangeable. Two basic approaches are considered: adding symmetry-breaking constraints to the model, and breaking symmetry during search. We also show how the two approaches can be combined in this case. We empirically compare several diierent approximations to eliminating the symmetry and an exact method that eliminates the symmetry completely, but is only feasible for small matrices.
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