ilog.opl

Class IloCplex.MIPCallback

java.lang.Object

ilog.opl.IloCplex.Callback

ilog.opl.IloCplex.MIPInfoCallback

ilog.opl.IloCplex.MIPCallback

All Implemented Interfaces:

java.lang.Cloneable

Direct Known Subclasses:

IloCplex.ControlCallback, IloCplex.DisjunctiveCutCallback, IloCplex.FlowMIRCutCallback, IloCplex.FractionalCutCallback, IloCplex.IncumbentCallback, IloCplex.NodeCallback, IloCplex.ProbingCallback

Enclosing class:

IloCplex

public abstract static class IloCplex.MIPCallback
extends IloCplex.MIPInfoCallback

The base class for all MIP callbacks.

An instance of the class MIPCallback represents a user-written callback in an application that uses an instance of IloCplex to solve a mixed integer program (MIP). IloCplex calls the user-written callback prior to solving each node in the branch-and-cut search. This class allows you to access an incumbent solution, an incumbent node, and an incumbent objective value from a user-written callback. It also allows you to access priority orders and statistical information such as the number of cuts that have been generated. Methods are also available to query the number of generated cuts for each type of cut CPLEX generates. See the ILOG CPLEX User's Manual for more information about cuts.

This class also provides a common application programming interface (API) for these subclasses:

• IloCplex.DisjunctiveCutCallback
• IloCplex.FractionalCutCallback
• IloCplex.FlowMIRCutCallback
• IloCplex.ProbingCallback
• IloCplex.IncumbentCallback
• IloCplex.NodeCallback
• IloCplex.SolveCallback
• IloCplex.ControlCallback with its extensions:
  • IloCplex.BranchCallback
  • IloCplex.HeuristicCallback

The constructor and methods of this class are protected to make sure that they are used only to derive a user-written callback class or to implement the main method in it.

See Also:

IloCplex.Callback

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	IloCplex.MIPCallback.NodeData Interface for user-objects attached to nodes.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	IloCplex.MIPCallback() Constructor for user-written MIP callback.

Method Summary

Methods

Modifier and Type	Method and Description
protected double	getObjCoef(IloNumVar var) Returns the linear objective function coefficient for variable var in the model being solved.
protected double[]	getObjCoefs(IloNumVar[] vars) Returns the linear objective function coefficients for an array of variables in the model being solved.
protected double[]	getObjCoefs(IloNumVar[] var, int start, int num) Returns the linear objective function coefficients for a set of variables in the model being solved.
protected int	getUserThreads()

Methods inherited from class ilog.opl.IloCplex.MIPInfoCallback

getBestObjValue, getCutoff, getDirection, getIncumbentObjValue, getIncumbentValue, getIncumbentValue, getIncumbentValues, getIncumbentValues, getMIPRelativeGap, getMyThreadNum, getNiterations, getNnodes, getNremainingNodes, getPriority, hasIncumbent

Methods inherited from class ilog.opl.IloCplex.Callback

abort, getCplexTime, getDetTime, getEndDetTime, getEndTime, getEnvImpl, getModel, getNcols, getNQCs, getNrows, getStartDetTime, getStartTime, main

Methods inherited from class java.lang.Object

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

Constructor Detail

IloCplex.MIPCallback

protected IloCplex.MIPCallback()

Constructor for user-written MIP callback. This constructor can be called only to construct objects of derived user-written callback classes, but not to construct IloCplex.MIPCallback objects directly.

Method Detail

getUserThreads

protected int getUserThreads()
                      throws IloException

Throws:

IloException

getObjCoef

protected double getObjCoef(IloNumVar var)
                     throws IloException

Returns the linear objective function coefficient for variable var in the model being solved.

Throws:

IloException

Parameters:

var - The variable whose linear objective coefficient is being queried.

Returns:

The linear objective coefficient for variable var in the model being solved.

getObjCoefs

protected double[] getObjCoefs(IloNumVar[] vars)
                        throws IloException

Returns the linear objective function coefficients for an array of variables in the model being solved.

Throws:

IloException

Parameters:

vars - An array of variables whose linear objective function coefficients are being queried.

Returns:

An array of double values containing the linear objective function coefficients for the specified variables in the problem being solved. If the returned array is called obj, obj[j] is the linear objective function coefficient for variable vars[j].

getObjCoefs

protected double[] getObjCoefs(IloNumVar[] var,
                   int start,
                   int num)
                        throws IloException

Returns the linear objective function coefficients for a set of variables in the model being solved.

Throws:

IloException

Parameters:

var - An array containing the variables whose linear objective function coefficients are being queried.

start - The index of the first variable in var for which to query the linear objective function coefficients.

num - The number of variables in vars for which to query the linear objective function coefficients.

Returns:

An array of double values containing the linear objective function coefficients for the specified variables in the problem being solved. If obj is the returned array, obj[j] is the linear objective function coefficient for variable vars[j+start], for j = 0, ..., num-1.