CPXgetcallbacknodex

Note

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 CPXgetcallbacknodex is used to get the primal variable (x) values for the subproblem at the current node during MIP optimization from within a user-written callback. The values are from the original problem if CPX_PARAM_MIPCBREDLP is set to CPX_OFF; otherwise, they are from the presolved problem.

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, or
CPX_CALLBACK_MIP_CUT.

Example

 status = CPXgetcallbacknodex (env, cbdata, wherefrom,
                               nodex, 0, cols-1);

See also admipex1.c, admipex3.c, and admipex5.c in the standard distribution.

A pointer to the CPLEX environment, as returned by CPXopenCPLEX.

The pointer passed to the user-written callback. This parameter must be the value of cbdata passed to the user-written callback.

An integer value indicating from where the user-written callback was called. The parameter must be the value of wherefrom passed to the user-written callback.

An array to receive the values of the primal variables for the node subproblem. This array must be of length at least (end - begin + 1). If successful, x[0] through x[end-begin] contain the primal values.

An integer indicating the beginning of the range of primal variable values for the node subproblem to be returned.

An integer indicating the end of the range of primal variable values for the node subproblem to be returned.

The routine returns zero on success and nonzero if an error occurs.

CPXgetcallbacknodex

Parameters:

Returns:

env	A pointer to the CPLEX environment, as returned by `CPXopenCPLEX`.
cbdata	The pointer passed to the user-written callback. This parameter must be the value of `cbdata` passed to the user-written callback.
wherefrom	An integer value indicating from where the user-written callback was called. The parameter must be the value of `wherefrom` passed to the user-written callback.
x	An array to receive the values of the primal variables for the node subproblem. This array must be of length at least (`end - begin + 1`). If successful, `x[0]` through `x[end-begin]` contain the primal values.
begin	An integer indicating the beginning of the range of primal variable values for the node subproblem to be returned.
end	An integer indicating the end of the range of primal variable values for the node subproblem to be returned.