ILOG CPLEX C++ API 9.0 Reference Manual

IloCplex::GoalI
GoalI::BranchType
GoalI::IntegerFeasibility
Inner Enumeration
GoalI::GoalI::IntegerFeasibi
lityArray
Inner Type Def
Description
Goals can be used to control the branch & cut search in IloCplex. Goals are
implemented in subclasses of the class IloCplex::GoalI. This is the base class for
user-written implementation classes of CPLEX goals.
To implement your own goal you need to create a subclass of IloCplex::GoalI and
implement its pure virtual methods execute and duplicateGoal. You may use
one of the ILOCPLEXGOAL0 macros to assist you in doing so. After implementing
your goal class, you use it by passing it to the solve method when solving the model.
The method duplicateGoal may be called by IloCplex to create copies of a goal
when needed for parallel branch & cut search. Thus the implementation of this method
must create and return an exact copy of the invoked object itself.
The method execute controls the branch & cut search of IloCplex by the goal it
returns. When IloCplex processes a node, it pops the top goal from the node's goal
stack and calls method execute of that goal. It continues executing the top goal from
the stack until the node is deactivated or the goal stack is empty. If the goal stack is
empty, IloCplex proceeds with the built-in search strategy for the subtree rooted at
the current node.
The class IloCplex::GoalI provides several methods for querying information
about the current node. The method execute controls how to proceed with the branch
& cut search via the goal it returns. The returned goal, unless it is the 0 goal, is pushed
on the goal stack and will thus be executed next.
See also the chapter about goals in the ILOG CPLEX User's Manual.
Constructors
public GoalI(IloEnv env)
The goal constructor. It requires an instance of the same IloEnv as the IloCplex
object with which to use the goal. The environment can later be queried by calling
method getEnv.
ILOG CPLEX C++ API 9.0 REFERENCE M ANUAL 137