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CPXcutcallbackadd
CPXcutcallbackadd
Usage
Mixed Integer Users Only
Description
The routine CPXcutcallbackadd() adds cuts during MIP branch & cut. This routine
may be called only from within user-written cut callbacks; thus it may be called only
when the value of its wherefrom argument is CPX_CALLBACK_MIP_CUT.
The cut may be for the original problem if the parameter CPX_PARAM_MIPCBREDLP was
set to CPX_OFF before the call to CPXmipopt() that calls the callback. Otherwise, the
cut is used on the presolved problem.
Return Value
The routine returns a zero on success, and a nonzero if an error occurs.
One possible error is indicated by the symbolic constant CPXERR_NO_SPACE. That error
occurs when the number of cuts added reaches the maximum allowed, as set by the
parameter CPX_PARAM_CUTSFACTOR.
Synopsis
Arguments
int CPXcutcallbackadd (CPXCENVptr env,
void *cbdata,
int wherefrom,
int *nzcnt,
double rhs,
int sense,
const int *cutind,
const double *cutval);
CPXCENVptr env
The pointer to the ILOG CPLEX environment, as returned by one of the CPXopenCPLEX
routines.
void *cbdata
The pointer passed to the user-written callback. This parameter must be the value of
cbdata passed to the user-written callback.
int wherefrom
An integer value that indicates where the user-written callback was called from. This
parameter must be the value of wherefrom passed to the user-written callback.
int *nzcnt
An integer value that indicates the number of coefficients in the cut, or equivalently, the
length of the arrays cutind and cutval.
double rhs
A double value that indicates the value of the right-hand side of the cut.
ILOG CPLEX 8.1 — ADVANCED REFERENCE MANUAL
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