CPXgetcallbackpseudocosts

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 CPXgetcallbackpseudocosts is used to get the pseudo-cost values 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.

Note

When pseudo-costs are retrieved for the original problem variables, pseudo-costs are zero for variables that have been removed from the problem, since they are never used for branching.

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 = CPXgetcallbackpseudocosts (env, cbdata, wherefrom,
                                     upcost, downcost,
                                     j, k);

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 up pseudo-costs. This array must be of length at least (end - begin + 1). If successful, uppc[0] through uppc[end-begin] will contain the up pseudo-costs. May be NULL.

An array to receive the values of the down pseudo-costs. This array must be of length at least (end - begin + 1). If successful, downpc[0] through downpc[end-begin] will contain the down pseudo-costs. May be NULL.

An integer indicating the beginning of the range of pseudo-costs to be returned.

An integer indicating the end of the range of pseudo-costs to be returned.

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

CPXgetcallbackpseudocosts

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.
uppc	An array to receive the values of up pseudo-costs. This array must be of length at least (`end - begin + 1`). If successful, `uppc[0]` through `uppc[end-begin]` will contain the up pseudo-costs. May be NULL.
downpc	An array to receive the values of the down pseudo-costs. This array must be of length at least (`end - begin + 1`). If successful, `downpc[0]` through `downpc[end-begin]` will contain the down pseudo-costs. May be NULL.
begin	An integer indicating the beginning of the range of pseudo-costs to be returned.
end	An integer indicating the end of the range of pseudo-costs to be returned.