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Modelling problem

Question asked by thomas.v on Sep 6, 2016
Latest reply on Sep 8, 2016 by Susanne.Heip

Hello,

 

I just started modelling with Mosel Xpress, and I'm stuck with programming one formula.

 

The formula avoids disjoint cycles in a Ring Star Problem, which is a Location problem in Telecommunications.

In my model, nodes i and j are in (set) V, with the arc {i,j} in (set) E. z is the variables to indicate if edge {i,j} is used in the cycle, where the binary variable x_ij indicates if node j is assigned to hub i. r is a given root node in the graph.

The formula is

denotes the cut induced by W.

Can any one help me program the above formula?

 

How do I program a (virtual) subset W that changes when taking another node i ?

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