void* problem_convert_to_osi(Problem *p)
{
int i;
double rowLb, rowUb;
OsiSolverInterface *solver = new OsiClpSolverInterface();
CoinBuild cb;
solver->setIntParam(OsiNameDiscipline, 2);
solver->messageHandler()->setLogLevel(0);
solver->setHintParam(OsiDoReducePrint,true,OsiHintTry);
for(i = 0; i < p->numCols; i++)
{
solver->addCol(0, NULL, NULL, p->colLb[i], p->colUb[i], p->objCoef[i]);
solver->setColName(i, p->colName[i]);
if(p->colType[i] == CONTINUOUS)
solver->setContinuous(i);
else
solver->setInteger(i);
}
for(i = 0; i < p->numRows; i++)
{
switch(p->rowSense[i])
{
case 'E':
rowLb = p->rhs[i];
rowUb = p->rhs[i];
break;
case 'L':
rowLb = -p->infty;
rowUb = p->rhs[i];
break;
case 'G':
rowLb = p->rhs[i];
rowUb = p->infty;
break;
default:
fprintf(stderr, "Error: invalid type of constraint!\n");
exit(EXIT_FAILURE);
}
cb.addRow(p->rowNElements[i], p->idxsByRow[i], p->coefsByRow[i], rowLb, rowUb);
}
solver->addRows(cb);
for(i = 0; i < p->numRows; i++)
solver->setRowName(i, p->rowName[i]);
return solver;
}
OsiSolverInterface* cpropagation_preprocess(CPropagation *cp, int nindexes[])
{
if(cp->varsToFix == 0)
{
/* printf("There are no variables to remove from the problem!\n"); */
return NULL; /* returns a pointer to original solver */
}
const double *colLb = problem_vars_lower_bound(cp->problem), *colUb = problem_vars_upper_bound(cp->problem);
const double *objCoef = problem_vars_obj_coefs(cp->problem);
const char *ctype = problem_vars_type(cp->problem);
double sumFixedObj = 0.0; /* stores the sum of objective coefficients of all variables fixed to 1 */
OsiSolverInterface *preProcSolver = new OsiClpSolverInterface();
preProcSolver->setIntParam(OsiNameDiscipline, 2);
preProcSolver->messageHandler()->setLogLevel(0);
preProcSolver->setHintParam(OsiDoReducePrint,true,OsiHintTry);
//preProcSolver->setObjName(cp->solver->getObjName());
for(int i = 0, j = 0; i < problem_num_cols(cp->problem); i++)
{
nindexes[i] = -1;
if(cp->isToFix[i] == UNFIXED)
{
preProcSolver->addCol(0, NULL, NULL, colLb[i], colUb[i], objCoef[i]);
preProcSolver->setColName(j, problem_var_name(cp->problem, i));
if(problem_var_type(cp->problem, i) == CONTINUOUS)
preProcSolver->setContinuous(j);
else
preProcSolver->setInteger(j);
nindexes[i] = j++;
}
else if(cp->isToFix[i] == ACTIVATE)
sumFixedObj += objCoef[i];
}
if(fabs(sumFixedObj) > EPS)
{
/* adding a variable with cost equals to the sum of all coefficients of variables fixed to 1 */
preProcSolver->addCol(0, NULL, NULL, 1.0, 1.0, sumFixedObj);
preProcSolver->setColName(preProcSolver->getNumCols()-1, "sumFixedObj");
preProcSolver->setInteger(preProcSolver->getNumCols()-1);
}
for(int idxRow = 0; idxRow < problem_num_rows(cp->problem); idxRow++)
{
const int nElements = problem_row_size(cp->problem, idxRow);
const int *idxs = problem_row_idxs(cp->problem, idxRow);
const double *coefs = problem_row_coefs(cp->problem, idxRow);
vector< int > vidx; vidx.reserve(problem_num_cols(cp->problem));
vector< double > vcoef; vcoef.reserve(problem_num_cols(cp->problem));
double activeCoefs = 0.0;
for(int i = 0; i < nElements; i++)
{
if(cp->isToFix[idxs[i]] == UNFIXED)
{
assert(nindexes[idxs[i]] >= 0 && nindexes[idxs[i]] < problem_num_cols(cp->problem));
vidx.push_back(nindexes[idxs[i]]);
vcoef.push_back(coefs[i]);
}
else if(cp->isToFix[idxs[i]] == ACTIVATE)
activeCoefs += coefs[i];
}
if(!vidx.empty())
{
double rlb, rub;
const char sense = problem_row_sense(cp->problem, idxRow);
if(sense == 'E')
{
rlb = problem_row_rhs(cp->problem, idxRow) - activeCoefs;
rub = problem_row_rhs(cp->problem, idxRow) - activeCoefs;
}
else if(sense == 'L')
{
rlb = preProcSolver->getInfinity();
rub = problem_row_rhs(cp->problem, idxRow) - activeCoefs;
}
else if(sense == 'G')
{
rlb = problem_row_rhs(cp->problem, idxRow) - activeCoefs;
rub = preProcSolver->getInfinity();
}
else
{
fprintf(stderr, "Error: invalid type of constraint!\n");
exit(EXIT_FAILURE);
}
preProcSolver->addRow((int)vcoef.size(), &vidx[0], &vcoef[0], rlb, rub);
preProcSolver->setRowName(idxRow, problem_row_name(cp->problem, idxRow));
}
}
return preProcSolver;
}
