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...
Ian P. Gent, Tom Kelsey, Steve Linton, Iain McDona...
We describe some new propagators for breaking symmetries in constraint satisfaction problems. We also introduce symmetry breaking constraints to deal with symmetries acting simulta...
We introduce a definition of constraint symmetry for soft CSPs, based on the definition of constraint symmetry for classical CSPs. We show that the constraint symmetry group of a...
Barbara M. Smith, Stefano Bistarelli, Barry O'Sull...
We introduce groupoids – generalisations of groups in which not all pairs of elements may be multiplied, or, equivalently, categories in which all morphisms are invertible – as...
Ian P. Gent, Tom Kelsey, S. A. Linton, J. Pearson,...
Symmetry is an important feature of many constraint programs. We show that any symmetry acting on a set of symmetry breaking constraints can be used to break symmetry. Different s...