ilog.concert
Class IloColumn

java.lang.Object
  |
  +--ilog.concert.IloColumn
public abstract class IloColumn
extends java.lang.Object

Objects of class IloColumn are used for creating a variable using column-wise modeling. Column-wise modeling means that at the time of construction, the variable is inserted into existing modeling objects. The term column-wise comes from linear programing, where the constraints are typically represented as a matrix. Adding a new variable to the optimization problem is equivalent to adding a column to the constraint matrix.

The procedure for column-wise modeling is as follows. Start from a set of modeling objects of these classes:

Call method IloMPModeler.column() with the object as parameter, along with the other parameters needed to install a new variable in the existing modeling objects. See the documentation of the IloMPModeler.column method for the details of these parameters. The methods in this class return objects of type IloColumnArray, and each of these methods contains the parameters required to install a new array of variables to the modeling object the IloColumnArray. All the IloColumn objects can then be linked to one IloColumn object. This object includes all the individual objects with the method IloColumn.add(). If the new variables are to be installed in only one modeling object, there is no need to use the method add().

The IloColumn object constructed this way is now ready to be used to create a new variable and install it in the existing modeling objects as described by the IloColumn object. This is done by passing the IloColumn object as a parameter to the constructor methods for variables, for example IloMPModeler.numVar() or IloMPModeler.intVar(). The newly created variable will immediately be part of the existing modeling objects that have been used for constructing the IloColumn object.
The following example function shows how to create a variable with bounds 0 and 1 and install it in an objective and a range constraint, with linear coefficients all set to 1: 

  IloNumVar newColumn(IloMPModeler modeler, IloObjective obj, IloRange rng) {
    IloColumn objcol = modeler.column(obj, 1.0);
    IloColumn rngcol = modeler.column(rng, 1.0);
    return modeler.numVar(objcol.and(rngcol), 0.0, 1.0);
  }

See Also:
IloMPModeler.column(IloObjective, double), IloMPModeler.column(IloLPMatrix), IloMPModeler.column(IloRange, double), IloMPModeler.numVar(IloColumn, double, double), IloMPModeler.intVar(IloColumn, int, int), IloMPModeler.semiContVar(IloColumn, double, double, IloNumVarType)

Constructor Summary
IloColumn()
           
 
Method Summary
 IloColumn and(IloColumn column)
          Links two IloColumn objects.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

IloColumn

public IloColumn()
Method Detail

and

public IloColumn and(IloColumn column)
Links two IloColumn objects. When using the returned IloColumn object for constructing a new variable, the new variable will be installed in the modeling objects handled by the invoking IloColumn object as well as the modeling objects handled by IloColumn passed as the parameter column.
Parameters:
column - The IloColumn object to be linked with the invoking IloColumn.
Returns:
An IloColumn object describing the addition of a newly created variable to the modeling objects handled by the invoking IloColumn, and the modeling objects handled by the argument column.