int
main(int argc,
char *argv[])
{
if (argc < 2)
{
cout << "Usage: lpmod_c++ filename" << endl;
return 1;
}
GRBEnv* env = 0;
GRBVar* v = 0;
try
{
// Read model and determine whether it is an LP
env = new GRBEnv();
GRBModel model = GRBModel(*env, argv[1]);
if (model.get(GRB_IntAttr_IsMIP) != 0)
{
cout << "The model is not a linear program" << endl;
return 1;
}
model.optimize();
int status = model.get(GRB_IntAttr_Status);
if ((status == GRB_INF_OR_UNBD) || (status == GRB_INFEASIBLE) ||
(status == GRB_UNBOUNDED))
{
cout << "The model cannot be solved because it is "
<< "infeasible or unbounded" << endl;
return 1;
}
if (status != GRB_OPTIMAL)
{
cout << "Optimization was stopped with status " << status << endl;
return 0;
}
// Find the smallest variable value
double minVal = GRB_INFINITY;
int minVar = 0;
v = model.getVars();
for (int j = 0; j < model.get(GRB_IntAttr_NumVars); ++j)
{
double sol = v[j].get(GRB_DoubleAttr_X);
if ((sol > 0.0001) && (sol < minVal) &&
(v[j].get(GRB_DoubleAttr_LB) == 0.0))
{
minVal = sol;
minVar = j;
}
}
cout << "\n*** Setting " << v[minVar].get(GRB_StringAttr_VarName)
<< " from " << minVal << " to zero ***" << endl << endl;
v[minVar].set(GRB_DoubleAttr_UB, 0.0);
// Solve from this starting point
model.optimize();
// Save iteration & time info
double warmCount = model.get(GRB_DoubleAttr_IterCount);
double warmTime = model.get(GRB_DoubleAttr_Runtime);
// Reset the model and resolve
cout << "\n*** Resetting and solving "
<< "without an advanced start ***\n" << endl;
model.reset();
model.optimize();
// Save iteration & time info
double coldCount = model.get(GRB_DoubleAttr_IterCount);
double coldTime = model.get(GRB_DoubleAttr_Runtime);
cout << "\n*** Warm start: " << warmCount << " iterations, " <<
warmTime << " seconds" << endl;
cout << "*** Cold start: " << coldCount << " iterations, " <<
coldTime << " seconds" << endl;
}
catch (GRBException e)
{
cout << "Error code = " << e.getErrorCode() << endl;
cout << e.getMessage() << endl;
}
catch (...)
{
cout << "Error during optimization" << endl;
}
delete[] v;
delete env;
return 0;
}
std::map<std::string,int>
ILP(char* argv)
{
map<string, int > results;
GRBVar* vars = 0;
// if (argc < 2) {
// cout << "Usage: lp_c++ filename" << endl;
// return 1;
// }
try {
GRBEnv env = GRBEnv();
GRBModel model = GRBModel(env, argv);
//model.getEnv().set(GRB_DoubleParam_IntFeasTol,1e-6);
model.getEnv().set(GRB_DoubleParam_Heuristics,0.95);
model.getEnv().set(GRB_DoubleParam_TimeLimit,timeMax);
model.getEnv().set(GRB_DoubleParam_MIPGap, ilpGap);
vars = model.getVars();
model.optimize();
int optimstatus = model.get(GRB_IntAttr_Status);
if (optimstatus == GRB_INF_OR_UNBD) {
model.getEnv().set(GRB_IntParam_Presolve, 0);
model.optimize();
optimstatus = model.get(GRB_IntAttr_Status);
}
if (optimstatus == GRB_OPTIMAL) {
double objval = model.get(GRB_DoubleAttr_ObjVal);
cout << "Optimal objective: " << objval << endl;
for(int i =0; i<model.get(GRB_IntAttr_NumVars);i++){
string varName = vars[i].get(GRB_StringAttr_VarName);
results[varName] = vars[i].get(GRB_DoubleAttr_X);
// cout << vars[i].get(GRB_StringAttr_VarName) << " " << vars[i].get(GRB_DoubleAttr_X) << endl;
}
ofstream varNames;
ofstream varResults;
varNames.open("varName.txt");
varResults.open("varResults.txt");
for(int i =0; i<model.get(GRB_IntAttr_NumVars);i++){
string varName = vars[i].get(GRB_StringAttr_VarName);
results[varName] = vars[i].get(GRB_DoubleAttr_X)+0.5; // +0.5 to make sure its round
if(varName == "co2o3storagey3" ){
cout << "gotte ya" <<endl;
}
varNames << varName << "\n";
varResults << varName << " "<< results[varName] << "\n";
//cout << vars[i].get(GRB_StringAttr_VarName) << " " << vars[i].get(GRB_DoubleAttr_X) << endl;
}
varNames.close();
varResults.close();
cout << "size of results is " << sizeof(results)*results.size()<< endl;
cout << "using mapSize function, size is " << mapSize(results)<<endl;
toFile(results,mapSize(results));
} else if (optimstatus == GRB_INFEASIBLE) {
cout << "Model is infeasible" << endl;
// compute and write out IIS
//model.computeIIS();
//model.write("model.ilp");
} else if (optimstatus == GRB_UNBOUNDED) {
cout << "Model is unbounded" << endl;
} else {
cout << "Optimization was stopped with status = "
<< optimstatus << endl;
double objval = model.get(GRB_DoubleAttr_ObjVal);
cout << "Optimal objective: " << objval << endl;
for(int i =0; i<model.get(GRB_IntAttr_NumVars);i++){
string varName = vars[i].get(GRB_StringAttr_VarName);
results[varName] = vars[i].get(GRB_DoubleAttr_X);
// cout << vars[i].get(GRB_StringAttr_VarName) << " " << vars[i].get(GRB_DoubleAttr_X) << endl;
}
ofstream varNames;
ofstream varResults;
varNames.open("varName.txt");
varResults.open("varResults.txt");
for(int i =0; i<model.get(GRB_IntAttr_NumVars);i++){
string varName = vars[i].get(GRB_StringAttr_VarName);
results[varName] = vars[i].get(GRB_DoubleAttr_X)+0.5; // +0.5 to make sure its round
if(varName == "co2o3storagey3" ){
cout << "gotte ya" <<endl;
}
varNames << varName << "\n";
varResults << varName << " = "<< results[varName] << "\n";
//cout << vars[i].get(GRB_StringAttr_VarName) << " " << vars[i].get(GRB_DoubleAttr_X) << endl;
}
varNames.close();
varResults.close();
}
} catch(GRBException e) {
cout << "Error code = " << e.getErrorCode() << endl;
cout << e.getMessage() << endl;
} catch (...) {
cout << "Error during optimization" << endl;
}
return results;
//return 0;
}
