ilog.cplex
Class IloCplex.LazyConstraintCallback

java.lang.Object
  |
  +--ilog.cplex.IloCplex.Callback
        |
        +--ilog.cplex.IloCplex.MIPCallback
              |
              +--ilog.cplex.IloCplex.ControlCallback
                    |
                    +--ilog.cplex.IloCplex.CutCallback
                          |
                          +--ilog.cplex.IloCplex.LazyConstraintCallback

All Implemented Interfaces:

java.lang.Cloneable

Enclosing class:

IloCplex

public abstract static class IloCplex.LazyConstraintCallback

extends IloCplex.CutCallback

This is an advanced method.

Important:

Advanced methods typically demand a profound understanding of the algorithms used by ILOG CPLEX. Thus they incur a higher risk of incorrect behavior in your application, behavior that can be difficult to debug. Therefore, ILOG encourages you to consider carefully whether you can accomplish the same task by means of other methods instead.

This is the lazy constraint callback class. Extensions of this class implement user-written lazy constraint callbacks. These allow you to add lazy constraint to the problem while the problem is being solved with branch-and-cut search. These lazy constraints may contribute to the model formulation and restrict the feasible region of the problem. By contrast, if a constraint to be added during branch-and-cut search does not change the feasible region of the active model but only strengthens the formulation, it is referred to as a user cut. Such constraints should better be added through a IloCplex.UserCutCallback because this allows IloCplex to potentially perform more presolve reductions. It is an error, however, to add lazy constraints using a user cut callback.

The idea behind lazy constraints is that the LPs that are solved when solving the MIP can be kept smaller when these constraints are not included. IloCplex will, however, include a lazy constraint in the LP as soon as it becomes violated. In other words, the solution computed by IloCplex makes sure that all the lazy constraints that have been added are satisfied.

The IloCplex.CutCallback is just another name for the IloCplex.LazyConstraintCallback class.

See Also:

IloCplex.ControlCallback, IloCplex.CutCallback, IloCplex.UserCutCallback

Constructor Summary

IloCplex.LazyConstraintCallback()

Methods inherited from class ilog.cplex.IloCplex.CutCallback

add, addLocal

Methods inherited from class ilog.cplex.IloCplex.ControlCallback

getDownPseudoCost, getFeasibilities, getFeasibilities, getFeasibility, getLB, getLBs, getLBs, getNodeData, getObjValue, getSlack, getSlacks, getSlacks, getSOSFeasibility, getSOSFeasibility, getUB, getUBs, getUBs, getUpPseudoCost, getValue, getValue, getValues, getValues

Methods inherited from class ilog.cplex.IloCplex.MIPCallback

getBestObjValue, getCutoff, getDirection, getIncumbentObjValue, getIncumbentValue, getIncumbentValues, getIncumbentValues, getMyThreadNum, getNcliques, getNcovers, getNdisjunctiveCuts, getNflowCovers, getNflowPaths, getNfractionalCuts, getNGUBcovers, getNimpliedBounds, getNiterations, getNMIRs, getNnodes, getNremainingNodes, getObjCoef, getObjCoefs, getObjCoefs, getPriority, getUserThreads, hasIncumbent

Methods inherited from class ilog.cplex.IloCplex.Callback

abort, getModel, getNcols, getNQCs, getNrows, main

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

IloCplex.LazyConstraintCallback

public IloCplex.LazyConstraintCallback()