//*******************************************************************
long CSolver:: GetBinaryCount() {
//! return CPXgetbinc(m_env,m_lp);
return CPXgetnumbin(m_env, m_lp);
}
int
main (int argc,
char *argv[])
{
int status = 0;
/* Declare and allocate space for the variables and arrays where
we will store the optimization results, including the status,
objective value, and variable values */
int solstat;
double objval;
double *x = NULL;
CPXENVptr env = NULL;
CPXLPptr lp = NULL;
int j;
int cur_numcols;
int wantorig = 1;
int nameind = 1;
/* Check the command line arguments */
if ( argc != 2 ) {
if ( argc != 3 ||
argv[1][0] != '-' ||
argv[1][1] != 'r' ) {
usage (argv[0]);
goto TERMINATE;
}
wantorig = 0;
nameind = 2;
}
/* Initialize the CPLEX environment */
env = CPXopenCPLEX (&status);
/* If an error occurs, the status value indicates the reason for
failure. A call to CPXgeterrorstring will produce the text of
the error message. Note that CPXopenCPLEX produces no
output, so the only way to see the cause of the error is to use
CPXgeterrorstring. For other CPLEX routines, the errors will
be seen if the CPXPARAM_ScreenOutput parameter is set to CPX_ON */
if ( env == NULL ) {
char errmsg[CPXMESSAGEBUFSIZE];
fprintf (stderr, "Could not open CPLEX environment.\n");
CPXgeterrorstring (env, status, errmsg);
fprintf (stderr, "%s", errmsg);
goto TERMINATE;
}
/* Turn on output to the screen */
status = CPXsetintparam (env, CPXPARAM_ScreenOutput, CPX_ON);
if ( status != 0 ) {
fprintf (stderr,
"Failure to turn on screen indicator, error %d.\n",
status);
goto TERMINATE;
}
/* Create the problem, using the filename as the problem name */
lp = CPXcreateprob (env, &status, argv[nameind]);
/* A returned pointer of NULL may mean that not enough memory
was available or there was some other problem. In the case of
failure, an error message will have been written to the error
channel from inside CPLEX. In this example, the setting of
the parameter CPXPARAM_ScreenOutput causes the error message to
appear on stdout. Note that most CPLEX routines return
an error code to indicate the reason for failure */
if ( lp == NULL ) {
fprintf (stderr, "Failed to create LP.\n");
goto TERMINATE;
}
/* Now read the file, and copy the data into the created lp */
status = CPXreadcopyprob (env, lp, argv[nameind], NULL);
if ( status ) {
fprintf (stderr,
"Failed to read and copy the problem data.\n");
goto TERMINATE;
}
if ( CPXgetnumcols (env, lp) != CPXgetnumbin (env, lp) ) {
fprintf (stderr, "Problem contains non-binary variables, exiting\n");
goto TERMINATE;
}
/* Set parameters */
if ( wantorig ) {
/* Assure linear mappings between the presolved and original
models */
status = CPXsetintparam (env, CPXPARAM_Preprocessing_Linear, 0);
if ( status ) goto TERMINATE;
/* Let MIP callbacks work on the original model */
status = CPXsetintparam (env, CPXPARAM_MIP_Strategy_CallbackReducedLP,
CPX_OFF);
if ( status ) goto TERMINATE;
}
status = CPXsetdblparam (env, CPXPARAM_MIP_Tolerances_MIPGap,
(double) 1e-6);
if ( status ) goto TERMINATE;
/* Turn on traditional search for use with control callbacks */
status = CPXsetintparam (env, CPXPARAM_MIP_Strategy_Search,
CPX_MIPSEARCH_TRADITIONAL);
if ( status ) goto TERMINATE;
/* Set up to use MIP callback */
status = CPXsetheuristiccallbackfunc (env, rounddownheur, NULL);
if ( status ) goto TERMINATE;
/* Optimize the problem and obtain solution */
status = CPXmipopt (env, lp);
if ( status ) {
fprintf (stderr, "Failed to optimize MIP.\n");
goto TERMINATE;
}
solstat = CPXgetstat (env, lp);
printf ("Solution status %d.\n", solstat);
status = CPXgetobjval (env, lp, &objval);
if ( status ) {
fprintf (stderr, "Failed to obtain objective value.\n");
goto TERMINATE;
}
printf ("Objective value %.10g\n", objval);
cur_numcols = CPXgetnumcols (env, lp);
/* Allocate space for solution */
x = (double *) malloc (cur_numcols * sizeof (double));
if ( x == NULL ) {
fprintf (stderr, "No memory for solution values.\n");
goto TERMINATE;
}
status = CPXgetx (env, lp, x, 0, cur_numcols-1);
if ( status ) {
fprintf (stderr, "Failed to obtain solution.\n");
goto TERMINATE;
}
/* Write out the solution */
for (j = 0; j < cur_numcols; j++) {
if ( fabs (x[j]) > 1e-10 ) {
printf ( "Column %d: Value = %17.10g\n", j, x[j]);
}
}
TERMINATE:
/* Free the solution vector */
free_and_null ((char **) &x);
/* Free the problem as allocated by CPXcreateprob and
CPXreadcopyprob, if necessary */
if ( lp != NULL ) {
status = CPXfreeprob (env, &lp);
if ( status ) {
fprintf (stderr, "CPXfreeprob failed, error code %d.\n",
status);
}
}
/* Free the CPLEX environment, if necessary */
if ( env != NULL ) {
status = CPXcloseCPLEX (&env);
/* Note that CPXcloseCPLEX produces no output, so the only
way to see the cause of the error is to use
CPXgeterrorstring. For other CPLEX routines, the errors
will be seen if the CPXPARAM_ScreenOutput parameter is set to
CPX_ON */
if ( status ) {
char errmsg[CPXMESSAGEBUFSIZE];
fprintf (stderr, "Could not close CPLEX environment.\n");
CPXgeterrorstring (env, status, errmsg);
fprintf (stderr, "%s", errmsg);
}
}
return (status);
} /* END main */
