CPXXcallbackgetlocallb and CPXcallbackgetlocallb

The routine CPXXcallbackgetlocallb/CPXcallbackgetlocallb retrieves the lower bound values for the subproblem at the current node during MIP optimization from within a user-written callback.

int CPXXcallbackgetlocallb( CPXCALLBACKCONTEXTptr context, double * lb, CPXDIM begin, CPXDIM end )

int CPXcallbackgetlocallb( CPXCALLBACKCONTEXTptr context, double * lb, int begin, int end )

Description

The routine CPXXcallbackgetlocallb/CPXcallbackgetlocallb retrieves the lower bound values for the subproblem at the current node during MIP optimization from within a user-written callback.

The routine can only be invoked if the current node is available. Precisely, the routine can only be invoked in the contexts:

CPX_CALLBACKCONTEXT_RELAXATION,
CPX_CALLBACKCONTEXT_BRANCHING,
CPX_CALLBACKCONTEXT_CANDIDATE, but only if the candidate solution comes from an integer feasible node (that is, the routine CPXXcallbackgetinfoint and CPXcallbackgetinfoint invoked with CPXCALLBACKINFO_CANDIDATE_SOURCE returns the value CPX_LAZYCONSTRAINTCALLBACK_NODE).

Arguments

context: The callback context as passed into the callback function.
lb: An array to receive the values of the lower bound values. This array must be of length at least (end-begin+1). If successful, lb[0] through lb[end-begin] contain the lower bound values for the current subproblem.
begin: An integer specifying the beginning of the range of lower bounds to be returned.
end: An integer specifying the end of the range of lower bounds to be returned.

Return

The routine returns 0 (zero) if successful and nonzero if an error occurs.

Example


 status = CPXcallbackgetlocallb (context, lb, 0, cols-1);