static char *row_name(struct csa *csa, int i, char rname[255+1])
{ /* construct symbolic name of i-th row (constraint) */
const char *name;
if (i == 0)
name = glp_get_obj_name(csa->P);
else
name = glp_get_row_name(csa->P, i);
if (name == NULL) goto fake;
strcpy(rname, name);
adjust_name(rname);
if (check_name(rname)) goto fake;
return rname;
fake: if (i == 0)
strcpy(rname, "obj");
else
sprintf(rname, "r_%d", i);
return rname;
}
const char *lpx_get_obj_name(LPX *lp)
{ /* retrieve objective function name */
return glp_get_obj_name(lp);
}
// read in all necessary elements for retrieving the LP/MILP
void Rglpk_read_file (char **file, int *type,
int *lp_direction_of_optimization,
int *lp_n_constraints, int *lp_n_objective_vars,
int *lp_n_values_in_constraint_matrix,
int *lp_n_integer_vars, int *lp_n_binary_vars,
char **lp_prob_name,
char **lp_obj_name,
int *lp_verbosity) {
int status;
extern glp_prob *lp;
glp_tran *tran;
const char *str;
// Turn on/off Terminal Output
if (*lp_verbosity==1)
glp_term_out(GLP_ON);
else
glp_term_out(GLP_OFF);
// create problem object
if (lp)
glp_delete_prob(lp);
lp = glp_create_prob();
// read file -> gets stored as an GLPK problem object 'lp'
// which file type do we have?
switch (*type){
case 1:
// Fixed (ancient) MPS Format, param argument currently NULL
status = glp_read_mps(lp, GLP_MPS_DECK, NULL, *file);
break;
case 2:
// Free (modern) MPS format, param argument currently NULL
status = glp_read_mps(lp, GLP_MPS_FILE, NULL, *file);
break;
case 3:
// CPLEX LP Format
status = glp_read_lp(lp, NULL, *file);
break;
case 4:
// MATHPROG Format (based on lpx_read_model function)
tran = glp_mpl_alloc_wksp();
status = glp_mpl_read_model(tran, *file, 0);
if (!status) {
status = glp_mpl_generate(tran, NULL);
if (!status) {
glp_mpl_build_prob(tran, lp);
}
}
glp_mpl_free_wksp(tran);
break;
}
// if file read successfully glp_read_* returns zero
if ( status != 0 ) {
glp_delete_prob(lp);
lp = NULL;
error("Reading file %s failed", *file);
}
// retrieve problem name
str = glp_get_prob_name(lp);
if (str){
*lp_prob_name = (char *) str;
}
// retrieve name of objective function
str = glp_get_obj_name(lp);
if (str){
*lp_obj_name = (char *) str;
}
// retrieve optimization direction flag
*lp_direction_of_optimization = glp_get_obj_dir(lp);
// retrieve number of constraints
*lp_n_constraints = glp_get_num_rows(lp);
// retrieve number of objective variables
*lp_n_objective_vars = glp_get_num_cols(lp);
// retrieve number of non-zero elements in constraint matrix
*lp_n_values_in_constraint_matrix = glp_get_num_nz(lp);
// retrieve number of integer variables
*lp_n_integer_vars = glp_get_num_int(lp);
// retrieve number of binary variables
*lp_n_binary_vars = glp_get_num_bin(lp);
}
