ILOG CPLEX C++ API 9.0 Reference Manual

IloCplex::DeleteMode
IloCplex::DeleteMode
Category
Definition File
Include Files
Synopsis
Description
See Also
Fields
Inner Enumeration
ilocplexi.h
ilcplex/ilocplex.h
DeleteMode{
LeaveBasis,
FixBasis
};
This enumeration lists the possible settings for the delete mode of IloCplex as
controlled by the method setDeleteMode and queried by the method
getDeleteMode.
◆ IloCplex::LeaveBasis
With the default setting IloCplex::LeaveBasis, an existing basis will remain
unchanged if variables or constraints are removed from the loaded LP model. This
choice generally renders the basis unusable for a restart when CPLEX is solving the
modified LP and the advance indicator (parameter IloCplex::AdvInd) is set to
IloTrue.
◆ IloCplex::FixBasis
In contrast, with delete mode set to IloCplex::FixBasis, the invoking object will
do basis pivots in order to maintain a valid basis when variables or constraints are
removed. This choice makes the delete operation more computation-intensive, but may
give a better starting point for reoptimization after modification of the extracted model.
If no basis is present in the invoking object, the setting of the delete mode has no effect.
IloCplex
LeaveBasis
FixBasis
ILOG CPLEX C++ API 9.0 REFERENCE M ANUAL 123