/*------------------------------------------------------------------*/ int main (int argc, char *argv[]) { int nStatus; int nHessOpt; /*---- DECLARE VARIABLES THAT ARE PASSED TO KNITRO. */ KTR_context *kc; int n, m, nnzJ, nnzH, objGoal, objType, objFnType; int *xType, *cType, *cFnType; int *jacIndexVars, *jacIndexCons, *hessRows, *hessCols; double obj, *x, *lambda; double *xLoBnds, *xUpBnds, *cLoBnds, *cUpBnds; /*---- FETCH THE SIZES OF THE PROBLEM TO BE SOLVED. */ getProblemSizes (&n, &m, &nnzJ, &nnzH); /*---- ALLOCATE MEMORY FOR THE PROBLEM DEFINITION. */ xType = (int *) malloc (n * sizeof(int)); xLoBnds = (double *) malloc (n * sizeof(double)); xUpBnds = (double *) malloc (n * sizeof(double)); cType = (int *) malloc (m * sizeof(int)); cFnType = (int *) malloc (m * sizeof(int)); cLoBnds = (double *) malloc (m * sizeof(double)); cUpBnds = (double *) malloc (m * sizeof(double)); jacIndexVars = (int *) malloc (nnzJ * sizeof(int)); jacIndexCons = (int *) malloc (nnzJ * sizeof(int)); hessRows = (int *) malloc (nnzH * sizeof(int)); hessCols = (int *) malloc (nnzH * sizeof(int)); /*---- FETCH THE DEFINITION OF THE PROBLEM TO BE SOLVED. */ getProblemData (&objType, &objGoal, xLoBnds, xUpBnds, NULL, cType, cLoBnds, cUpBnds, jacIndexVars, jacIndexCons, hessRows, hessCols, &objFnType, xType, cFnType); /*---- NOW THAT WE HAVE THE PROBLEM SIZE, ALLOCATE ARRAYS THAT ARE *---- PASSED TO KNITRO DURING THE SOLVE. *---- *---- NOTICE lambda HAS MULTIPLIERS FOR BOTH CONSTRAINTS AND BOUNDS *---- (A COMMON MISTAKE IS TO ALLOCATE ITS SIZE AS m). */ x = (double *) malloc (n * sizeof(double)); lambda = (double *) malloc ((m+n) * sizeof(double)); /*---- CREATE A NEW KNITRO SOLVER INSTANCE. */ kc = KTR_new(); if (kc == NULL) { printf ("Failed to find a Ziena license.\n"); return( -1 ); } /*---- ILLUSTRATE HOW TO OVERRIDE DEFAULT OPTIONS. *---- OPTIONS MUST BE SET BEFORE CALLING KTR_mip_init_problem. *---- (SEE callbackExample1.c FOR OTHER TECHNIQUES.) */ if (KTR_set_int_param_by_name (kc, "mip_method", KTR_MIP_METHOD_BB) != 0) return( -1 ); if (KTR_set_int_param_by_name (kc, "algorithm", KTR_ALG_ACT_CG) != 0) return( -1 ); if (KTR_set_int_param_by_name (kc, "outmode", KTR_OUTMODE_SCREEN) != 0) return( -1 ); if (KTR_set_int_param (kc, KTR_PARAM_OUTLEV, KTR_OUTLEV_ALL) != 0) return( -1 ); if (KTR_set_int_param (kc, KTR_PARAM_MIP_OUTINTERVAL, 1) != 0) return( -1 ); if (KTR_set_int_param (kc, KTR_PARAM_MIP_MAXNODES, 10000) != 0) return( -1 ); /*---- SPECIFY THAT THE USER IS ABLE TO PROVIDE EVALUATIONS *---- OF THE HESSIAN MATRIX WITHOUT THE OBJECTIVE COMPONENT. *---- TURNED OFF BY DEFAULT BUT SHOULD BE ENABLED IF POSSIBLE. */ if (KTR_set_int_param (kc, KTR_PARAM_HESSIAN_NO_F, KTR_HESSIAN_NO_F_ALLOW) != 0) return( -1 ); /*---- REGISTER THE CALLBACK FUNCTIONS THAT PERFORM PROBLEM EVALUATION. *---- THE HESSIAN CALLBACK ONLY NEEDS TO BE REGISTERED FOR SPECIFIC *---- HESSIAN OPTIONS (E.G., IT IS NOT REGISTERED IF THE OPTION FOR *---- BFGS HESSIAN APPROXIMATIONS IS SELECTED). */ if (KTR_set_func_callback (kc, &callbackEvalFC) != 0) exit( -1 ); if (KTR_set_grad_callback (kc, &callbackEvalGA) != 0) exit( -1 ); if (KTR_get_int_param_by_name (kc, "hessopt", &nHessOpt) != 0) exit( -1 ); if ((nHessOpt == KTR_HESSOPT_EXACT) || (nHessOpt == KTR_HESSOPT_PRODUCT)) { if (KTR_set_hess_callback (kc, &callbackEvalHess) != 0) exit( -1 ); } /*---- REGISTER THE CALLBACK FUNCTION THAT PERFORMS SOME TASK AFTER *---- EACH COMPLETION OF EACH NODE IN BRANCH-AND-BOUND TREE. */ if (KTR_set_mip_node_callback (kc, &callbackProcessNode) != 0) exit( -1 ); /*---- INITIALIZE KNITRO WITH THE PROBLEM DEFINITION. */ nStatus = KTR_mip_init_problem (kc, n, objGoal, objType, objFnType, xType, xLoBnds, xUpBnds, m, cType, cFnType, cLoBnds, cUpBnds, nnzJ, jacIndexVars, jacIndexCons, nnzH, hessRows, hessCols, NULL, NULL); /*---- KNITRO KEEPS ITS OWN COPY OF THE PROBLEM DEFINITION, *---- SO THE LOCAL MEMORY CAN BE FREED IMMEDIATELY. */ free (xType); free (xLoBnds); free (xUpBnds); free (cType); free (cFnType); free (cLoBnds); free (cUpBnds); free (jacIndexVars); free (jacIndexCons); free (hessRows); free (hessCols); /*---- SOLVE THE PROBLEM. *---- *---- RETURN STATUS CODES ARE DEFINED IN "knitro.h" AND DESCRIBED *---- IN THE KNITRO MANUAL. */ nStatus = KTR_mip_solve (kc, x, lambda, 0, &obj, NULL, NULL, NULL, NULL, NULL, kc); printf ("\n\n"); if (nStatus != 0) printf ("KNITRO failed to solve the problem, final status = %d\n", nStatus); else { /*---- AN EXAMPLE OF OBTAINING SOLUTION INFORMATION. */ printf ("KNITRO successful, integrality gap = %e\n", KTR_get_mip_abs_gap (kc)); } /*---- DELETE THE KNITRO SOLVER INSTANCE. */ KTR_free (&kc); free (x); free (lambda); return( 0 ); }
static void knitro_finalize( value knitro ) { KTR_context* context = context_of_block( knitro ); KTR_free( &context ); }