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ColgenInstance:minimize(+SolveSubProblem, +Obj, -ObjVal)

Minimizes the problem associated with the colgen instance ColgenInstance.
SolveSubProblem
Subproblem solution predicate
Obj
The objective function to minimize
ObjVal
The optimal solution cost

Description

Minimize the partial linear expression Obj for the problem associated with the colgen instance ColgenInstance, using the user-defined predicate SolveSubProblem to provide profitable variables during solution. The optimal solution cost is unified with ObjVal.

The first argument of the subproblem solution predicate must be a subproblem structure:

      sp_prob(master_pool, cutoff, cost, coeff_vars, aux, module)
 
where and master_pool will be unified with the colgen instance ColgenInstance so that solutions can be posted to it from within the solution predicate, cutoff is a minimum acceptable value for the cost of subproblem solutions that will be updated before calling the predicate, cost is the variable occurring in the implicit sum term of obj (if any) representing the contribution of new subproblem solutions to the master problem solution cost, coeff_vars is a list of all subproblem variables occurring in the implicit sum terms of master problem constraints, and module is the module in which the solution predicate should be called.