Bound-consistent spread constraint

Bound-Consistent Deviation Constraint

Deviation is a recent constraint to balance a set of variables with respect to a given mean. We show that the propagators recently introduced are not bound-consistent when the mean is rational. We introduce bound-consistent propagators running in linear time with respect to the number of variables. We evaluate the improvement in terms of efficiency and pruning obtained with the new propagators ...

Consistent Orderings for Constraint

The job shop scheduling problem has been formulated in Constraint Logic Programming as one of nding a consistent assignment of start times for each operation of each job. Nonetheless, in some proposals within the Artiicial Intelligence area, the problem has been alternatively formulated as one of establishing sequencing constraints between pairs of operations contending for the same resource ov...

Locally consistent constraint satisfaction problems

An instance of a constraint satisfaction problem (CSP) is variable k-consistent if any subinstance with at most k variables has a solution. For a fixed constraint language L, ρk(L) is the largest ratio such that any variable k-consistent instance has a solution that satisfies at least a fraction of ρk(L) of the constraints. We provide an expression for the limit ρ(L) := limk→∞ ρk(L), and show t...

Locally Consistent Constraint Satisfaction Problems

Simplification and extension of the SPREAD Constraint

Many assignment problems require the solution to be balanced. Such a problem is the Balanced Academic Curriculum Problem (BACP) [1]. Standard deviation is a common way to measure the balance of a set of values. A recent constraint presented by Pesant and Régin [2] enforces the mean μ and the standard deviation σ of a set of variables. Our work extends [2] by showing a more simple propagator fro...