Basis Information
When solving an LP using all but IloCplex.Algorithm.Barrier without crossover, or when solving a QP with a Simplex optimizer, basis information is available as well. Basis information can be queried for the variables and ranged constraints of the active model using method IloCplex.getBasisStatus(). This method returns basis statuses for the variables or constraints using objects of type IloCplex.BasisStatus, with possible values::
IloCplex.BasisStatus.Basic,IloCplex.BasisStatus.AtLower,IloCplex.BasisStatus.AtUpper, andIloCplex.BasisStatus.FreeOrSuperbasic.
The availability of a basis for an LP allows you to perform sensitivity analysis for your model. Such analysis tells you by how much you can modify your model without affecting the solution you found. The modifications supported by the sensitivity analysis function include variable bound changes, changes to the bounds of ranged constraints, and changes to the objective function. They are analyzed by methods IloCplex.getBoundSA(), IloCplex.getRangeSA(), IloCplex.getRHSSA() and IloCplex.getObjSA(), respectively.
