void kMST_ILP::solve()
{
try {
// initialize CPLEX
env = IloEnv();
model = IloModel( env );
Variables *vars;
// add model-specific constraints
if( model_type == "scf" ) vars = modelSCF();
else if( model_type == "mcf" ) vars = modelMCF();
else if( model_type == "mtz" ) vars = modelMTZ();
else {
cerr << "No existing model chosen\n";
exit( -1 );
}
// build model
cplex = IloCplex( model );
// export model to a text file
//cplex.exportModel( "model.lp" );
// set parameters
setCPLEXParameters();
// solve model
cout << "Calling CPLEX solve ...\n";
cplex.solve();
cout << "CPLEX finished.\n\n";
cout << "CPLEX status: " << cplex.getStatus() << "\n";
cout << "Branch-and-Bound nodes: " << cplex.getNnodes() << "\n";
cout << "Objective value: " << cplex.getObjValue() << "\n";
cout << "CPU time: " << Tools::CPUtime() << "\n\n";
// vars->print(cplex);
delete vars;
}
catch( IloException& e ) {
cerr << "kMST_ILP: exception " << e << "\n";
exit( -1 );
}
catch( ... ) {
cerr << "kMST_ILP: unknown exception.\n";
exit( -1 );
}
}
void kMST_ILP::solve()
{
try {
// initialize CPLEX
env = IloEnv();
model = IloModel( env );
addTreeConstraints(); // call first, initialises edges
// add model-specific constraints
if( model_type == "scf" ) modelSCF();
else if( model_type == "mcf" ) modelMCF();
else if( model_type == "mtz" ) modelMTZ();
else {
cerr << "No existing model chosen\n";
exit( -1 );
}
addObjectiveFunction();
// build model
cplex = IloCplex( model );
// export model to a text file
//cplex.exportModel( "model.lp" );
// set parameters
setCPLEXParameters();
// solve model
cout << "Calling CPLEX solve ...\n";
cplex.solve();
cout << "CPLEX finished.\n\n";
cout << "CPLEX status: " << cplex.getStatus() << "\n";
cout << "Branch-and-Bound nodes: " << cplex.getNnodes() << "\n";
cout << "Objective value: " << cplex.getObjValue() << "\n";
cout << "CPU time: " << Tools::CPUtime() << "\n\n";
// show result
IloNumArray edgesSelected(env, edges.getSize()), flowRes(env, edges.getSize()), uRes(env, instance.n_nodes);
cplex.getValues(edgesSelected, edges);
if (model_type == "scf") {
cplex.getValues(flowRes, flow_scf);
} else if (model_type == "mtz") {
try {
cplex.getValues(uRes, u);
} catch ( IloException& e ) {
cerr << "Exception while extracting u: " << e << endl;
uRes = IloNumArray(env, 0);
}
}
cout << "Edges:\n";
for (unsigned int i=0; i<edges.getSize(); i++) {
// skip unused ones
if (((int)edgesSelected[i]) == 0 ) {
continue;
}
if (i == instance.n_edges) {
cout << endl;
}
bool direction = ( i >= instance.n_edges);
cout << " " << setw(4) << i << ": " << ((int)edgesSelected[i]) << " ";
// flow
if (model_type == "scf") {
cout << "f: " << setw(2) << (flowRes[i]);
} else if (model_type == "mtz") {
if (uRes.getSize() != 0) {
cout << "u: " ;
if (i < instance.n_edges) {
//cout << setw(2) << instance.edges[i % instance.n_edges].v1 << ": ";
cout << setw(2) <<((int)uRes[ instance.edges[i % instance.n_edges].v1]) << " ";
//cout << setw(2) << instance.edges[i % instance.n_edges].v2 << ": ";
cout << setw(2) << ((int)uRes[ instance.edges[i % instance.n_edges].v2]) ;
} else {
//cout << setw(2) << instance.edges[i % instance.n_edges].v2 << ": ";
cout << setw(2) <<((int)uRes[ instance.edges[i % instance.n_edges].v2]) << " ";
//cout << setw(2) << instance.edges[i % instance.n_edges].v1 << ": ";
cout << setw(2) <<((int)uRes[ instance.edges[i % instance.n_edges].v1]) ;
}
}
}
cout << " " << Tools::edgeToString(instance.edges[i % instance.n_edges], direction) ;
cout << endl;
}
} catch (IloAlgorithm::CannotExtractException& e) {
cerr << "CannotExtractException: " << e << endl ;
IloExtractableArray failed = e.getExtractables();
for (IloInt i = 0; i < failed.getSize(); ++i) {
cerr << "\t" << failed[i] << std::endl;
}
} catch( IloException& e ) {
cerr << "kMST_ILP: exception " << e << "\n";
exit( -1 );
}
catch( ... ) {
cerr << "kMST_ILP: unknown exception.\n";
exit( -1 );
}
}
