#include <ilcplex/cplex.h>
#include <stdlib.h>
#include <string.h>
#define NUMROWS 2
#define NUMCOLS 3
#define NUMNZ 6
int
main (int argc, char **argv)
{
int status = 0;
CPXENVptr env = NULL;
CPXLPptr lp = NULL;
double obj[NUMCOLS];
double lb[NUMCOLS];
double ub[NUMCOLS];
double x[NUMCOLS];
int rmatbeg[NUMROWS];
int rmatind[NUMNZ];
double rmatval[NUMNZ];
double rhs[NUMROWS];
char sense[NUMROWS];
int solstat;
double objval;
env = CPXopenCPLEX (&status);
if ( env == NULL ) {
char errmsg[1024];
fprintf (stderr, "Could not open CPLEX environment.\n");
CPXgeterrorstring (env, status, errmsg);
fprintf (stderr, "%s", errmsg);
goto TERMINATE;
}
lp = CPXcreateprob (env, &status, "lpex1");
if ( lp == NULL ) {
fprintf (stderr, "Failed to create LP.\n");
goto TERMINATE;
}
CPXchgobjsen (env, lp, CPX_MAX);
obj[0] = 1.0; obj[1] = 2.0; obj[2] = 3.0;
lb[0] = 0.0; lb[1] = 0.0; lb[2] = 0.0;
ub[0] = 40.0; ub[1] = CPX_INFBOUND; ub[2] = CPX_INFBOUND;
status = CPXnewcols (env, lp, NUMCOLS, obj, lb, ub, NULL, NULL);
if ( status ) {
fprintf (stderr, "Failed to populate problem.\n");
goto TERMINATE;
}
rmatbeg[0] = 0;
rmatind[0] = 0; rmatind[1] = 1; rmatind[2] = 2; sense[0] = 'L';
rmatval[0] = -1.0; rmatval[1] = 1.0; rmatval[2] = 1.0; rhs[0] = 20.0;
rmatbeg[1] = 3;
rmatind[3] = 0; rmatind[4] = 1; rmatind[5] = 2; sense[1] = 'L';
rmatval[3] = 1.0; rmatval[4] = -3.0; rmatval[5] = 1.0; rhs[1] = 30.0;
status = CPXaddrows (env, lp, 0, NUMROWS, NUMNZ, rhs, sense, rmatbeg,
rmatind, rmatval, NULL, NULL);
if ( status ) {
fprintf (stderr, "Failed to populate problem.\n");
goto TERMINATE;
}
status = CPXlpopt (env, lp);
if ( status ) {
fprintf (stderr, "Failed to optimize LP.\n");
goto TERMINATE;
}
status = CPXsolution (env, lp, &solstat, &objval, x, NULL, NULL, NULL);
if ( status ) {
fprintf (stderr, "Failed to obtain solution.\n");
goto TERMINATE;
}
printf ("\nSolution status = %d\n", solstat);
printf ("Solution value = %f\n", objval);
printf ("Solution = [%f, %f, %f]\n\n", x[0], x[1], x[2]);
TERMINATE:
if ( lp != NULL ) {
status = CPXfreeprob (env, &lp);
if ( status ) {
fprintf (stderr, "CPXfreeprob failed, error code %d.\n", status);
}
}
if ( env != NULL ) {
status = CPXcloseCPLEX (&env);
if ( status ) {
char errmsg[1024];
fprintf (stderr, "Could not close CPLEX environment.\n");
CPXgeterrorstring (env, status, errmsg);
fprintf (stderr, "%s", errmsg);
}
}
return (status);
} /* END main */
|
