This function creates and returns a search selector to act as a filter during the search for a solution in a Concert Technology model.

The search selector that this function creates and returns does several things:

• It stores the leaf of the search tree corresponding to the optimal value of the variable var and then reactivates this variable after the complete exploration of the search tree.
• It manages the upper bound on the objective variable. As soon as a solution of value d is found, the constraint var <= d - step is added to the model for the remainder of the search.
• Open nodes are evaluated. The evaluation of an open node is equal to the current minimum of the variable var when the node is created. When the search requires an open node, it checks whether the current upper bound on the objective is less than the evaluation of the node. If so, the node is safely discarded.

When this function takes an instance of the class IloEnv as a parameter, it returns an instance of IloSearchSelector for use with the member functions IloSolver::startNewSearch and IloSolver::solve. An instance of IloSolver extracts the search selector that it returns as an instance of IlcSearchSelector for use during a Solver search.