/* Generate cuts for the model data contained in si.
The generated cuts are inserted into and returned in the
collection of cuts cs.
*/
bool
AbcCutGenerator::generateCuts( OsiCuts & cs , bool fullScan)
{
int howOften = whenCutGenerator_;
if (howOften == -100)
return false;
if (howOften > 0)
howOften = howOften % 1000000;
else
howOften = 1;
if (!howOften)
howOften = 1;
bool returnCode = false;
OsiSolverInterface * solver = model_->solver();
#if defined(ABC_DEBUG_MORE)
std::cout << "model_->getNodeCount() = " << model_->getNodeCount()
<< std::endl;
#endif
if (fullScan || (model_->getNodeCount() % howOften) == 0 ) {
CglProbing* generator =
dynamic_cast<CglProbing*>(generator_);
if (!generator) {
generator_->generateCuts(*solver,cs);
} else {
// Probing - return tight column bounds
CglTreeInfo info;
generator->generateCutsAndModify(*solver,cs,&info);
const double * tightLower = generator->tightLower();
const double * lower = solver->getColLower();
const double * tightUpper = generator->tightUpper();
const double * upper = solver->getColUpper();
const double * solution = solver->getColSolution();
int j;
int numberColumns = solver->getNumCols();
double primalTolerance = 1.0e-8;
for (j=0; j<numberColumns; j++) {
if (tightUpper[j] == tightLower[j] &&
upper[j] > lower[j]) {
// fix
solver->setColLower(j, tightLower[j]);
solver->setColUpper(j, tightUpper[j]);
if (tightLower[j] > solution[j] + primalTolerance ||
tightUpper[j] < solution[j] - primalTolerance)
returnCode = true;
}
}
}
}
return returnCode;
}
bool
BlisConGenerator::generateCons(OsiCuts & coinCuts , bool fullScan)
{
bool status = false;
if (strategy_ == -2) {
// This con generator has been disabled.
return false;
}
OsiSolverInterface * solver = model_->solver();
#if defined(BLIS_DEBUG_MORE)
std::cout << "model_->getNodeCount() = " << model_->getNodeCount()
<< std::endl;
#endif
if ( fullScan ||
((strategy_ > 0) && (model_->getNumNodes() % strategy_) == 0) ) {
//--------------------------------------------------
// Start to generate cons ...
//--------------------------------------------------
int j;
double start = CoinCpuTime();
int numConsBefore = coinCuts.sizeCuts();
int numRowsBefore = coinCuts.sizeRowCuts();
assert(generator_ != NULL);
CglProbing* generator = dynamic_cast<CglProbing *>(generator_);
if (!generator) {
generator_->generateCuts(*solver, coinCuts);
}
else {
// It is probing - return tight column bound
CglTreeInfo info;
generator->generateCutsAndModify(*solver, coinCuts, &info);
const double * tightLower = generator->tightLower();
const double * lower = solver->getColLower();
const double * tightUpper = generator->tightUpper();
const double * upper = solver->getColUpper();
const double * solution = solver->getColSolution();
int numberColumns = solver->getNumCols();
double primalTolerance = 1.0e-8;
for (j = 0; j < numberColumns; ++j) {
if ( (tightUpper[j] == tightLower[j]) &&
(upper[j] > lower[j]) ) {
// fix column j
solver->setColLower(j, tightLower[j]);
solver->setColUpper(j, tightUpper[j]);
if ( (tightLower[j] > solution[j] + primalTolerance) ||
(tightUpper[j] < solution[j] - primalTolerance) ) {
status = true;
}
}
}
} // EOF probing.
//--------------------------------------------------
// Remove zero length row cuts.
//--------------------------------------------------
int numRowCons = coinCuts.sizeRowCuts();
for (j = numRowsBefore; j < numRowCons; ++j) {
OsiRowCut & rCut = coinCuts.rowCut(j);
int len = rCut.row().getNumElements();
#ifdef BLIS_DEBUG_MORE
std::cout << "Cut " << j<<": length = " << len << std::endl;
#endif
if (len == 0) {
// Empty cuts
coinCuts.eraseRowCut(j);
--j;
--numRowCons;
#ifdef BLIS_DEBUG
std::cout << "WARNING: Empty cut from " << name_ << std::endl;
#endif
}
else if (len < 0) {
#ifdef BLIS_DEBUG
std::cout << "ERROR: Cut length = " << len << std::endl;
#endif
// Error
assert(0);
}
}
//--------------------------------------------------
// Update statistics.
//--------------------------------------------------
++calls_;
numConsGenerated_ += (coinCuts.sizeCuts() - numConsBefore);
time_ += (CoinCpuTime() - start);
if (numConsGenerated_ == 0) {
++noConsCalls_;
}
}
return status;
}
// Generate constraints for the model data contained in si.
// The generated constraints are inserted into and returned in the
// constraint pool.
// Default implementation use Cgl cut generators.
bool
BlisConGenerator::generateConstraints(BcpsConstraintPool &conPool)
{
bool status = false;
OsiSolverInterface * solver = model_->solver();
#if defined(BLIS_DEBUG_MORE)
std::cout << "model_->getNodeCount() = " << model_->getNodeCount()
<< std::endl;
#endif
//--------------------------------------------------
// Start to generate constraints...
//--------------------------------------------------
assert(generator_ != NULL);
int j;
OsiCuts newOsiCuts;
CglProbing* generator = dynamic_cast<CglProbing *>(generator_);
if (generator) {
// It is CglProbing - return tight column bounds
CglTreeInfo info;
generator->generateCutsAndModify(*solver, newOsiCuts, &info);
const double * tightLower = generator->tightLower();
const double * lower = solver->getColLower();
const double * tightUpper = generator->tightUpper();
const double * upper = solver->getColUpper();
const double * solution = solver->getColSolution();
int numberColumns = solver->getNumCols();
double primalTolerance = 1.0e-8;
for (j = 0; j < numberColumns; ++j) {
if ( (tightUpper[j] == tightLower[j]) &&
(upper[j] > lower[j]) ) {
// Fix column j
solver->setColLower(j, tightLower[j]);
solver->setColUpper(j, tightUpper[j]);
if ( (tightLower[j] > solution[j] + primalTolerance) ||
(tightUpper[j] < solution[j] - primalTolerance) ) {
status = true;
}
}
}
}
else {
// Other Cgl cut generators
generator_->generateCuts(*solver, newOsiCuts);
}
//--------------------------------------------------
// Create blis constraints and remove zero length row cuts.
//--------------------------------------------------
int numNewConstraints = newOsiCuts.sizeRowCuts();
for (j = 0; j < numNewConstraints; ++j) {
OsiRowCut & rCut = newOsiCuts.rowCut(j);
int len = rCut.row().getNumElements();
#ifdef BLIS_DEBUG_MORE
std::cout << "Cut " << j<<": length = " << len << std::endl;
#endif
if (len > 0) {
// Create BlisConstraints from OsiCuts.
BlisConstraint *blisCon = BlisOsiCutToConstraint(&rCut);
conPool.addConstraint(blisCon);
}
else if (len == 0) {
// Empty cuts
#ifdef BLIS_DEBUG
std::cout << "WARNING: Empty cut from " << name_ << std::endl;
#endif
}
else {
#ifdef BLIS_DEBUG
std::cout << "ERROR: Cut length = " << len << std::endl;
#endif
// Error
assert(0);
}
}
// Adjust cut strategy.
if ( (strategy_ == BlisCutStrategyAuto) &&
(noConsCalls_ > BLIS_CUT_DISABLE) ) {
strategy_ = BlisCutStrategyNone;
}
return status;
}
