ILOG CPLEX 11.0 User's Manual

In the Java API, a Fail goal is returned by the method IloCplex.failGoal.In the .NET API, a Fail goal is returned by the method Cplex.FailGoal.Local Cut GoalA local cut goal adds a local cut to the node where the goal is executed.In the C++ API, the class IloCplex::Goal has constructors that take an instance ofIloRange or an instance of IloRangeArray (IloRange[]) as an argument. When one ofthese constructors is used, a local cut goal is created.To create local cut goals with the Java API, use the method IloCplex.constraintGoalor if more convenient, one of the methods IloCplex.leGoal, IloCplex.geGoal orIloCplex.eqGoal.In the .NET API, use the methods Cplex.ConstraintGoal, Cplex.EqGoal,Cplex.LeGoal, or CplexGeGoal to create a local cut goal.Null GoalThe 0-goal is also known as a null goal or empty goal.In the C++ API, a null goal is an IloCplex::Goal handle object with a null (0)implementation pointer.A null goal can also be returned by the method IloCplex::GoalI::execute.Use a null goal when you want to instruct ILOG CPLEX not to branch any further. Forexample, when CPLEX finds a feasible solution, and you want to accept it without furtherbranching, a null goal is appropriate.For example, the following sample from the C++ API accepts an integer feasible solutionand stops branching.if ( isIntegerFeasible() )return 0;Branch as CPLEX GoalInstead of instructing ILOG CPLEX not to branch any further (as you can do with a nullgoal), it is also possible to tell ILOG CPLEX to branch as it normally would; in other words,to branch as CPLEX. You give ILOG CPLEX this instruction by means of a branching goal.A branching goal tells ILOG CPLEX to take over control of the branch & cut search with itsbuilt-in strategies.ILOG CPLEX 11.0 — USER’ S MANUAL 431