| Overview | Group | Tree | Graph | Index | Concepts |
This is an advanced routine. Advanced routines typically demand a profound understanding of the algorithms used by ILOG CPLEX. Thus they incur a higher risk of incorrect behavior in your application, behavior that can be difficult to debug. Therefore, ILOG encourages you to consider carefully whether you can accomplish the same task by means of other Callable Library routines instead.
The routine CPXgetcallbacklp is used to get the pointer to
the MIP problem that is in use when the user-written callback function is
called. It is the original MIP if CPX_PARAM_MIPCBREDLP is set
to CPX_OFF; otherwise, it is the presolved MIP. In contrast, the
function CPXgetcallbacknodelp returns a
pointer to the node subproblem, which is an LP. Generally, this pointer may
be used only in CPLEX Callable Library query routines, such as
CPXsolution or CPXgetrows.
This routine may be called only when the value of the
wherefrom argument is one of the following:
CPX_CALLBACK_MIP,
CPX_CALLBACK_MIP_BRANCH,
CPX_CALLBACK_MIP_INCUMBENT,
CPX_CALLBACK_MIP_NODE,
CPX_CALLBACK_MIP_HEURISTIC,
CPX_CALLBACK_MIP_SOLVE, or
CPX_CALLBACK_MIP_CUT.
Example
status = CPXgetcallbacklp (env, cbdata, wherefrom, &origlp);
See also admipex1.c,
admipex2.c, and admipex3.c
in the standard distribution.
| env | A pointer to the CPLEX environment, as returned by |
| cbdata | The pointer passed to the user-written callback. This parameter must be the value of |
| wherefrom | An integer value indicating from where the user-written callback was called. The parameter must be the value of |
| lp_p | A pointer to a variable of type |