Objects of class Column
are used to create a variable using column-wise modeling.
For a list of all members of this type, see Column Members.
System.Object
ILOG.Concert.Column
Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.
In column-wise modeling, newly constructed variables are inserted into existing modeling objects. The term column-wise comes from linear programming, where the constraints are typically represented as a matrix. Adding new variables to the optimization problem corresponds to adding columns to the constraint matrix.
The procedure for column-wise modeling is as follows. Start from an existing set of modeling objects of these classes:
IObjective
,IRange
, andILPMatrix
For each modeling object affected by the addition of the new variable, call the method IMPModeler.Column
with the object as an argument, along with the other arguments needed to install a new variable in the existing modeling objects. See the documentation of the IMPModeler.Column methods for the details of these arguments. Each of these methods returns an object of type Column that contains information about how to add a new variable to the modeling object for which the IMPModeler.Column method has been called.
The column objects can then be linked to an aggregate column object by the method Column.And. This aggregate object contains information about how to add a new variable to all of the modeling objects represented by its parts. If the new variable is to be installed in only one modeling object, there is no need to use the method Column.And.
The column object constructed this way is now ready to be used to create a new variable. This is done by passing the column object as an argument to the constructor methods for variables, for example IMPModeler.NumVar or IMPModeler.IntVar. The newly created variable will immediately be part of the existing modeling objects that have been used to construct the column object.
Namespace: ILOG.Concert
Assembly: ILOG.CPLEX (in ILOG.CPLEX.dll)