CPX_CALLBACKCONTEXT_RELAXATION

Generic callback at relaxation solution candidate

#define CPX_CALLBACKCONTEXT_RELAXATION 0x0040

Description

CPLEX invokes the generic callback in this context when it has found a relaxed solution available. The relaxed solution is usually not integer feasible. It can, for example, be the solution to a node LP (but can also come from another place). You can query the relaxed solution with the routine CPXXcallbackgetrelaxationpoint and CPXcallbackgetrelaxationpoint.

The constant is used in two different ways:
  • As a value passed into the generic callback function to specify in which context the generic callback is invoked.
  • As a bit-wise OR with the where argument of the routine CPXXcallbacksetfunc and CPXcallbacksetfunc to specify in which situations CPLEX should invoke the generic callback.
Important: All information queried from a callback in this context is local to the thread.

Incompatibility with Benders algorithm

This context is incompatible with Benders algorithm.

See also