// Override OsiSolver::solve() because Soplex doesn't have branch & bound
int OsiSpxSolver::solve() {
OsiSolverInterface* si = OsiSolver::getSolver();
if(!OsiSolver::prepareSolve()) {
return UNSAT;
}
timer.reset();
try {
si->initialSolve();
} catch (CoinError err) {
err.print(true);
return UNSAT;
}
time = timer.timeElapsed();
if (si->isProvenOptimal())
return SAT;
else if (si->isProvenPrimalInfeasible())
return UNSAT;
else
return UNKNOWN;
}
// inner part of dive
int
CbcHeuristicDive::solution(double & solutionValue, int & numberNodes,
int & numberCuts, OsiRowCut ** cuts,
CbcSubProblem ** & nodes,
double * newSolution)
{
#ifdef DIVE_DEBUG
int nRoundInfeasible = 0;
int nRoundFeasible = 0;
#endif
int reasonToStop = 0;
double time1 = CoinCpuTime();
int numberSimplexIterations = 0;
int maxSimplexIterations = (model_->getNodeCount()) ? maxSimplexIterations_
: maxSimplexIterationsAtRoot_;
// but can't be exactly coin_int_max
maxSimplexIterations = CoinMin(maxSimplexIterations,COIN_INT_MAX>>3);
OsiSolverInterface * solver = cloneBut(6); // was model_->solver()->clone();
# ifdef COIN_HAS_CLP
OsiClpSolverInterface * clpSolver
= dynamic_cast<OsiClpSolverInterface *> (solver);
if (clpSolver) {
ClpSimplex * clpSimplex = clpSolver->getModelPtr();
int oneSolveIts = clpSimplex->maximumIterations();
oneSolveIts = CoinMin(1000+2*(clpSimplex->numberRows()+clpSimplex->numberColumns()),oneSolveIts);
clpSimplex->setMaximumIterations(oneSolveIts);
if (!nodes) {
// say give up easily
clpSimplex->setMoreSpecialOptions(clpSimplex->moreSpecialOptions() | 64);
} else {
// get ray
int specialOptions = clpSimplex->specialOptions();
specialOptions &= ~0x3100000;
specialOptions |= 32;
clpSimplex->setSpecialOptions(specialOptions);
clpSolver->setSpecialOptions(clpSolver->specialOptions() | 1048576);
if ((model_->moreSpecialOptions()&16777216)!=0) {
// cutoff is constraint
clpSolver->setDblParam(OsiDualObjectiveLimit, COIN_DBL_MAX);
}
}
}
# endif
const double * lower = solver->getColLower();
const double * upper = solver->getColUpper();
const double * rowLower = solver->getRowLower();
const double * rowUpper = solver->getRowUpper();
const double * solution = solver->getColSolution();
const double * objective = solver->getObjCoefficients();
double integerTolerance = model_->getDblParam(CbcModel::CbcIntegerTolerance);
double primalTolerance;
solver->getDblParam(OsiPrimalTolerance, primalTolerance);
int numberRows = matrix_.getNumRows();
assert (numberRows <= solver->getNumRows());
int numberIntegers = model_->numberIntegers();
const int * integerVariable = model_->integerVariable();
double direction = solver->getObjSense(); // 1 for min, -1 for max
double newSolutionValue = direction * solver->getObjValue();
int returnCode = 0;
// Column copy
const double * element = matrix_.getElements();
const int * row = matrix_.getIndices();
const CoinBigIndex * columnStart = matrix_.getVectorStarts();
const int * columnLength = matrix_.getVectorLengths();
#ifdef DIVE_FIX_BINARY_VARIABLES
// Row copy
const double * elementByRow = matrixByRow_.getElements();
const int * column = matrixByRow_.getIndices();
const CoinBigIndex * rowStart = matrixByRow_.getVectorStarts();
const int * rowLength = matrixByRow_.getVectorLengths();
#endif
// Get solution array for heuristic solution
int numberColumns = solver->getNumCols();
memcpy(newSolution, solution, numberColumns*sizeof(double));
// vectors to store the latest variables fixed at their bounds
int* columnFixed = new int [numberIntegers];
double* originalBound = new double [numberIntegers+2*numberColumns];
double * lowerBefore = originalBound+numberIntegers;
double * upperBefore = lowerBefore+numberColumns;
memcpy(lowerBefore,lower,numberColumns*sizeof(double));
memcpy(upperBefore,upper,numberColumns*sizeof(double));
double * lastDjs=newSolution+numberColumns;
bool * fixedAtLowerBound = new bool [numberIntegers];
PseudoReducedCost * candidate = new PseudoReducedCost [numberIntegers];
double * random = new double [numberIntegers];
int maxNumberAtBoundToFix = static_cast<int> (floor(percentageToFix_ * numberIntegers));
assert (!maxNumberAtBoundToFix||!nodes);
// count how many fractional variables
int numberFractionalVariables = 0;
for (int i = 0; i < numberIntegers; i++) {
random[i] = randomNumberGenerator_.randomDouble() + 0.3;
int iColumn = integerVariable[i];
double value = newSolution[iColumn];
if (fabs(floor(value + 0.5) - value) > integerTolerance) {
numberFractionalVariables++;
}
}
const double* reducedCost = NULL;
// See if not NLP
if (model_->solverCharacteristics()->reducedCostsAccurate())
reducedCost = solver->getReducedCost();
int iteration = 0;
while (numberFractionalVariables) {
iteration++;
// initialize any data
initializeData();
// select a fractional variable to bound
int bestColumn = -1;
int bestRound; // -1 rounds down, +1 rounds up
bool canRound = selectVariableToBranch(solver, newSolution,
bestColumn, bestRound);
// if the solution is not trivially roundable, we don't try to round;
// if the solution is trivially roundable, we try to round. However,
// if the rounded solution is worse than the current incumbent,
// then we don't round and proceed normally. In this case, the
// bestColumn will be a trivially roundable variable
if (canRound) {
// check if by rounding all fractional variables
// we get a solution with an objective value
// better than the current best integer solution
double delta = 0.0;
for (int i = 0; i < numberIntegers; i++) {
int iColumn = integerVariable[i];
double value = newSolution[iColumn];
if (fabs(floor(value + 0.5) - value) > integerTolerance) {
assert(downLocks_[i] == 0 || upLocks_[i] == 0);
double obj = objective[iColumn];
if (downLocks_[i] == 0 && upLocks_[i] == 0) {
if (direction * obj >= 0.0)
delta += (floor(value) - value) * obj;
else
delta += (ceil(value) - value) * obj;
} else if (downLocks_[i] == 0)
delta += (floor(value) - value) * obj;
else
delta += (ceil(value) - value) * obj;
}
}
if (direction*(solver->getObjValue() + delta) < solutionValue) {
#ifdef DIVE_DEBUG
nRoundFeasible++;
#endif
if (!nodes||bestColumn<0) {
// Round all the fractional variables
for (int i = 0; i < numberIntegers; i++) {
int iColumn = integerVariable[i];
double value = newSolution[iColumn];
if (fabs(floor(value + 0.5) - value) > integerTolerance) {
assert(downLocks_[i] == 0 || upLocks_[i] == 0);
if (downLocks_[i] == 0 && upLocks_[i] == 0) {
if (direction * objective[iColumn] >= 0.0)
newSolution[iColumn] = floor(value);
else
newSolution[iColumn] = ceil(value);
} else if (downLocks_[i] == 0)
newSolution[iColumn] = floor(value);
else
newSolution[iColumn] = ceil(value);
}
}
break;
} else {
// can't round if going to use in branching
int i;
for (i = 0; i < numberIntegers; i++) {
int iColumn = integerVariable[i];
double value = newSolution[bestColumn];
if (fabs(floor(value + 0.5) - value) > integerTolerance) {
if (iColumn==bestColumn) {
assert(downLocks_[i] == 0 || upLocks_[i] == 0);
double obj = objective[bestColumn];
if (downLocks_[i] == 0 && upLocks_[i] == 0) {
if (direction * obj >= 0.0)
bestRound=-1;
else
bestRound=1;
} else if (downLocks_[i] == 0)
bestRound=-1;
else
bestRound=1;
break;
}
}
}
}
}
#ifdef DIVE_DEBUG
else
nRoundInfeasible++;
#endif
}
// do reduced cost fixing
#ifdef DIVE_DEBUG
int numberFixed = reducedCostFix(solver);
std::cout << "numberReducedCostFixed = " << numberFixed << std::endl;
#else
reducedCostFix(solver);
#endif
int numberAtBoundFixed = 0;
#ifdef DIVE_FIX_BINARY_VARIABLES
// fix binary variables based on pseudo reduced cost
if (binVarIndex_.size()) {
int cnt = 0;
int n = static_cast<int>(binVarIndex_.size());
for (int j = 0; j < n; j++) {
int iColumn1 = binVarIndex_[j];
double value = newSolution[iColumn1];
if (fabs(value) <= integerTolerance &&
lower[iColumn1] != upper[iColumn1]) {
double maxPseudoReducedCost = 0.0;
#ifdef DIVE_DEBUG
std::cout << "iColumn1 = " << iColumn1 << ", value = " << value << std::endl;
#endif
int iRow = vbRowIndex_[j];
double chosenValue = 0.0;
for (int k = rowStart[iRow]; k < rowStart[iRow] + rowLength[iRow]; k++) {
int iColumn2 = column[k];
#ifdef DIVE_DEBUG
std::cout << "iColumn2 = " << iColumn2 << std::endl;
#endif
if (iColumn1 != iColumn2) {
double pseudoReducedCost = fabs(reducedCost[iColumn2] *
elementByRow[k]);
#ifdef DIVE_DEBUG
int k2;
for (k2 = rowStart[iRow]; k2 < rowStart[iRow] + rowLength[iRow]; k2++) {
if (column[k2] == iColumn1)
break;
}
std::cout << "reducedCost[" << iColumn2 << "] = "
<< reducedCost[iColumn2]
<< ", elementByRow[" << iColumn2 << "] = " << elementByRow[k]
<< ", elementByRow[" << iColumn1 << "] = " << elementByRow[k2]
<< ", pseudoRedCost = " << pseudoReducedCost
<< std::endl;
#endif
if (pseudoReducedCost > maxPseudoReducedCost)
maxPseudoReducedCost = pseudoReducedCost;
} else {
// save value
chosenValue = fabs(elementByRow[k]);
}
}
assert (chosenValue);
maxPseudoReducedCost /= chosenValue;
#ifdef DIVE_DEBUG
std::cout << ", maxPseudoRedCost = " << maxPseudoReducedCost << std::endl;
#endif
candidate[cnt].var = iColumn1;
candidate[cnt++].pseudoRedCost = maxPseudoReducedCost;
}
}
#ifdef DIVE_DEBUG
std::cout << "candidates for rounding = " << cnt << std::endl;
#endif
std::sort(candidate, candidate + cnt, compareBinaryVars);
for (int i = 0; i < cnt; i++) {
int iColumn = candidate[i].var;
if (numberAtBoundFixed < maxNumberAtBoundToFix) {
columnFixed[numberAtBoundFixed] = iColumn;
originalBound[numberAtBoundFixed] = upper[iColumn];
fixedAtLowerBound[numberAtBoundFixed] = true;
solver->setColUpper(iColumn, lower[iColumn]);
numberAtBoundFixed++;
if (numberAtBoundFixed == maxNumberAtBoundToFix)
break;
}
}
}
#endif
// fix other integer variables that are at their bounds
int cnt = 0;
#ifdef GAP
double gap = 1.0e30;
#endif
if (reducedCost && true) {
#ifndef JJF_ONE
cnt = fixOtherVariables(solver, solution, candidate, random);
#else
#ifdef GAP
double cutoff = model_->getCutoff() ;
if (cutoff < 1.0e20 && false) {
double direction = solver->getObjSense() ;
gap = cutoff - solver->getObjValue() * direction ;
gap *= 0.1; // Fix more if plausible
double tolerance;
solver->getDblParam(OsiDualTolerance, tolerance) ;
if (gap <= 0.0)
gap = tolerance;
gap += 100.0 * tolerance;
}
int nOverGap = 0;
#endif
int numberFree = 0;
int numberFixed = 0;
for (int i = 0; i < numberIntegers; i++) {
int iColumn = integerVariable[i];
if (upper[iColumn] > lower[iColumn]) {
numberFree++;
double value = newSolution[iColumn];
if (fabs(floor(value + 0.5) - value) <= integerTolerance) {
candidate[cnt].var = iColumn;
candidate[cnt++].pseudoRedCost =
fabs(reducedCost[iColumn] * random[i]);
#ifdef GAP
if (fabs(reducedCost[iColumn]) > gap)
nOverGap++;
#endif
}
} else {
numberFixed++;
}
}
#ifdef GAP
int nLeft = maxNumberAtBoundToFix - numberAtBoundFixed;
#ifdef CLP_INVESTIGATE4
printf("cutoff %g obj %g nover %d - %d free, %d fixed\n",
cutoff, solver->getObjValue(), nOverGap, numberFree, numberFixed);
#endif
if (nOverGap > nLeft && true) {
nOverGap = CoinMin(nOverGap, nLeft + maxNumberAtBoundToFix / 2);
maxNumberAtBoundToFix += nOverGap - nLeft;
}
#else
#ifdef CLP_INVESTIGATE4
printf("cutoff %g obj %g - %d free, %d fixed\n",
model_->getCutoff(), solver->getObjValue(), numberFree, numberFixed);
#endif
#endif
#endif
} else {
for (int i = 0; i < numberIntegers; i++) {
int iColumn = integerVariable[i];
if (upper[iColumn] > lower[iColumn]) {
double value = newSolution[iColumn];
if (fabs(floor(value + 0.5) - value) <= integerTolerance) {
candidate[cnt].var = iColumn;
candidate[cnt++].pseudoRedCost = numberIntegers - i;
}
}
}
}
std::sort(candidate, candidate + cnt, compareBinaryVars);
for (int i = 0; i < cnt; i++) {
int iColumn = candidate[i].var;
if (upper[iColumn] > lower[iColumn]) {
double value = newSolution[iColumn];
if (fabs(floor(value + 0.5) - value) <= integerTolerance &&
numberAtBoundFixed < maxNumberAtBoundToFix) {
// fix the variable at one of its bounds
if (fabs(lower[iColumn] - value) <= integerTolerance) {
columnFixed[numberAtBoundFixed] = iColumn;
originalBound[numberAtBoundFixed] = upper[iColumn];
fixedAtLowerBound[numberAtBoundFixed] = true;
solver->setColUpper(iColumn, lower[iColumn]);
numberAtBoundFixed++;
} else if (fabs(upper[iColumn] - value) <= integerTolerance) {
columnFixed[numberAtBoundFixed] = iColumn;
originalBound[numberAtBoundFixed] = lower[iColumn];
fixedAtLowerBound[numberAtBoundFixed] = false;
solver->setColLower(iColumn, upper[iColumn]);
numberAtBoundFixed++;
}
if (numberAtBoundFixed == maxNumberAtBoundToFix)
break;
}
}
}
#ifdef DIVE_DEBUG
std::cout << "numberAtBoundFixed = " << numberAtBoundFixed << std::endl;
#endif
double originalBoundBestColumn;
double bestColumnValue;
int whichWay;
if (bestColumn >= 0) {
bestColumnValue = newSolution[bestColumn];
if (bestRound < 0) {
originalBoundBestColumn = upper[bestColumn];
solver->setColUpper(bestColumn, floor(bestColumnValue));
whichWay=0;
} else {
originalBoundBestColumn = lower[bestColumn];
solver->setColLower(bestColumn, ceil(bestColumnValue));
whichWay=1;
}
} else {
break;
}
int originalBestRound = bestRound;
int saveModelOptions = model_->specialOptions();
while (1) {
model_->setSpecialOptions(saveModelOptions | 2048);
solver->resolve();
model_->setSpecialOptions(saveModelOptions);
if (!solver->isAbandoned()&&!solver->isIterationLimitReached()) {
numberSimplexIterations += solver->getIterationCount();
} else {
numberSimplexIterations = maxSimplexIterations + 1;
reasonToStop += 100;
break;
}
if (!solver->isProvenOptimal()) {
if (nodes) {
if (solver->isProvenPrimalInfeasible()) {
if (maxSimplexIterationsAtRoot_!=COIN_INT_MAX) {
// stop now
printf("stopping on first infeasibility\n");
break;
} else if (cuts) {
// can do conflict cut
printf("could do intermediate conflict cut\n");
bool localCut;
OsiRowCut * cut = model_->conflictCut(solver,localCut);
if (cut) {
if (!localCut) {
model_->makePartialCut(cut,solver);
cuts[numberCuts++]=cut;
} else {
delete cut;
}
}
}
} else {
reasonToStop += 10;
break;
}
}
if (numberAtBoundFixed > 0) {
// Remove the bound fix for variables that were at bounds
for (int i = 0; i < numberAtBoundFixed; i++) {
int iColFixed = columnFixed[i];
if (fixedAtLowerBound[i])
solver->setColUpper(iColFixed, originalBound[i]);
else
solver->setColLower(iColFixed, originalBound[i]);
}
numberAtBoundFixed = 0;
} else if (bestRound == originalBestRound) {
bestRound *= (-1);
whichWay |=2;
if (bestRound < 0) {
solver->setColLower(bestColumn, originalBoundBestColumn);
solver->setColUpper(bestColumn, floor(bestColumnValue));
} else {
solver->setColLower(bestColumn, ceil(bestColumnValue));
solver->setColUpper(bestColumn, originalBoundBestColumn);
}
} else
break;
} else
break;
}
if (!solver->isProvenOptimal() ||
direction*solver->getObjValue() >= solutionValue) {
reasonToStop += 1;
} else if (iteration > maxIterations_) {
reasonToStop += 2;
} else if (CoinCpuTime() - time1 > maxTime_) {
reasonToStop += 3;
} else if (numberSimplexIterations > maxSimplexIterations) {
reasonToStop += 4;
// also switch off
#ifdef CLP_INVESTIGATE
printf("switching off diving as too many iterations %d, %d allowed\n",
numberSimplexIterations, maxSimplexIterations);
#endif
when_ = 0;
} else if (solver->getIterationCount() > 1000 && iteration > 3 && !nodes) {
reasonToStop += 5;
// also switch off
#ifdef CLP_INVESTIGATE
printf("switching off diving one iteration took %d iterations (total %d)\n",
solver->getIterationCount(), numberSimplexIterations);
#endif
when_ = 0;
}
memcpy(newSolution, solution, numberColumns*sizeof(double));
numberFractionalVariables = 0;
double sumFractionalVariables=0.0;
for (int i = 0; i < numberIntegers; i++) {
int iColumn = integerVariable[i];
double value = newSolution[iColumn];
double away = fabs(floor(value + 0.5) - value);
if (away > integerTolerance) {
numberFractionalVariables++;
sumFractionalVariables += away;
}
}
if (nodes) {
// save information
//branchValues[numberNodes]=bestColumnValue;
//statuses[numberNodes]=whichWay+(bestColumn<<2);
//bases[numberNodes]=solver->getWarmStart();
ClpSimplex * simplex = clpSolver->getModelPtr();
CbcSubProblem * sub =
new CbcSubProblem(clpSolver,lowerBefore,upperBefore,
simplex->statusArray(),numberNodes);
nodes[numberNodes]=sub;
// other stuff
sub->branchValue_=bestColumnValue;
sub->problemStatus_=whichWay;
sub->branchVariable_=bestColumn;
sub->objectiveValue_ = simplex->objectiveValue();
sub->sumInfeasibilities_ = sumFractionalVariables;
sub->numberInfeasibilities_ = numberFractionalVariables;
printf("DiveNode %d column %d way %d bvalue %g obj %g\n",
numberNodes,sub->branchVariable_,sub->problemStatus_,
sub->branchValue_,sub->objectiveValue_);
numberNodes++;
if (solver->isProvenOptimal()) {
memcpy(lastDjs,solver->getReducedCost(),numberColumns*sizeof(double));
memcpy(lowerBefore,lower,numberColumns*sizeof(double));
memcpy(upperBefore,upper,numberColumns*sizeof(double));
}
}
if (!numberFractionalVariables||reasonToStop)
break;
}
if (nodes) {
printf("Exiting dive for reason %d\n",reasonToStop);
if (reasonToStop>1) {
printf("problems in diving\n");
int whichWay=nodes[numberNodes-1]->problemStatus_;
CbcSubProblem * sub;
if ((whichWay&2)==0) {
// leave both ways
sub = new CbcSubProblem(*nodes[numberNodes-1]);
nodes[numberNodes++]=sub;
} else {
sub = nodes[numberNodes-1];
}
if ((whichWay&1)==0)
sub->problemStatus_=whichWay|1;
else
sub->problemStatus_=whichWay&~1;
}
if (!numberNodes) {
// was good at start! - create fake
clpSolver->resolve();
ClpSimplex * simplex = clpSolver->getModelPtr();
CbcSubProblem * sub =
new CbcSubProblem(clpSolver,lowerBefore,upperBefore,
simplex->statusArray(),numberNodes);
nodes[numberNodes]=sub;
// other stuff
sub->branchValue_=0.0;
sub->problemStatus_=0;
sub->branchVariable_=-1;
sub->objectiveValue_ = simplex->objectiveValue();
sub->sumInfeasibilities_ = 0.0;
sub->numberInfeasibilities_ = 0;
printf("DiveNode %d column %d way %d bvalue %g obj %g\n",
numberNodes,sub->branchVariable_,sub->problemStatus_,
sub->branchValue_,sub->objectiveValue_);
numberNodes++;
assert (solver->isProvenOptimal());
}
nodes[numberNodes-1]->problemStatus_ |= 256*reasonToStop;
// use djs as well
if (solver->isProvenPrimalInfeasible()&&cuts) {
// can do conflict cut and re-order
printf("could do final conflict cut\n");
bool localCut;
OsiRowCut * cut = model_->conflictCut(solver,localCut);
if (cut) {
printf("cut - need to use conflict and previous djs\n");
if (!localCut) {
model_->makePartialCut(cut,solver);
cuts[numberCuts++]=cut;
} else {
delete cut;
}
} else {
printf("bad conflict - just use previous djs\n");
}
}
}
// re-compute new solution value
double objOffset = 0.0;
solver->getDblParam(OsiObjOffset, objOffset);
newSolutionValue = -objOffset;
for (int i = 0 ; i < numberColumns ; i++ )
newSolutionValue += objective[i] * newSolution[i];
newSolutionValue *= direction;
//printf("new solution value %g %g\n",newSolutionValue,solutionValue);
if (newSolutionValue < solutionValue && !reasonToStop) {
double * rowActivity = new double[numberRows];
memset(rowActivity, 0, numberRows*sizeof(double));
// paranoid check
memset(rowActivity, 0, numberRows*sizeof(double));
for (int i = 0; i < numberColumns; i++) {
int j;
double value = newSolution[i];
if (value) {
for (j = columnStart[i];
j < columnStart[i] + columnLength[i]; j++) {
int iRow = row[j];
rowActivity[iRow] += value * element[j];
}
}
}
// check was approximately feasible
bool feasible = true;
for (int i = 0; i < numberRows; i++) {
if (rowActivity[i] < rowLower[i]) {
if (rowActivity[i] < rowLower[i] - 1000.0*primalTolerance)
feasible = false;
} else if (rowActivity[i] > rowUpper[i]) {
if (rowActivity[i] > rowUpper[i] + 1000.0*primalTolerance)
feasible = false;
}
}
for (int i = 0; i < numberIntegers; i++) {
int iColumn = integerVariable[i];
double value = newSolution[iColumn];
if (fabs(floor(value + 0.5) - value) > integerTolerance) {
feasible = false;
break;
}
}
if (feasible) {
// new solution
solutionValue = newSolutionValue;
//printf("** Solution of %g found by CbcHeuristicDive\n",newSolutionValue);
//if (cuts)
//clpSolver->getModelPtr()->writeMps("good8.mps", 2);
returnCode = 1;
} else {
// Can easily happen
//printf("Debug CbcHeuristicDive giving bad solution\n");
}
delete [] rowActivity;
}
#ifdef DIVE_DEBUG
std::cout << "nRoundInfeasible = " << nRoundInfeasible
<< ", nRoundFeasible = " << nRoundFeasible
<< ", returnCode = " << returnCode
<< ", reasonToStop = " << reasonToStop
<< ", simplexIts = " << numberSimplexIterations
<< ", iterations = " << iteration << std::endl;
#endif
delete [] columnFixed;
delete [] originalBound;
delete [] fixedAtLowerBound;
delete [] candidate;
delete [] random;
delete [] downArray_;
downArray_ = NULL;
delete [] upArray_;
upArray_ = NULL;
delete solver;
return returnCode;
}
int main( int argc, char **argv )
{
if ( argc < 2 )
{
printf("Invalid number of parameters!\n");
exit( EXIT_FAILURE );
}
char problemName[ 256 ];
getFileName( problemName, argv[1] );
clock_t start = clock();
OsiClpSolverInterface *realSolver = new OsiClpSolverInterface();
realSolver->getModelPtr()->setPerturbation(50); /* makes CLP faster for hard instances */
OsiSolverInterface *solver = (OsiSolverInterface*) realSolver;
parseParameters( argc, argv );
readLP( solver, argv[1] );
FILE *log = NULL;
if(!output.empty())
{
log = fopen(output.c_str(), "a");
if(!log)
{
printf("Could not open the file!\n");
exit(EXIT_FAILURE);
}
}
const int numCols = solver->getNumCols(), numRows = solver->getNumRows();
int pass = 0, newCuts = 0, totalCuts = 0;
double pTime, opt, cgTime;
CGraph *cgraph = NULL;
if(sepMethod == Npsep)
cgraph = build_cgraph_osi( solver );
if(!optFile.empty())
{
getOptimals();
if(optimals.find(problemName) == optimals.end())
{
fprintf(stderr, "ERROR: optimal value not found!\n");
exit(EXIT_FAILURE);
}
opt = optimals[problemName];
}
solver->initialSolve();
if (!solver->isProvenOptimal())
{
if (solver->isAbandoned())
{
fprintf( stderr, "LP solver abandoned due to numerical dificulties.\n" );
exit( EXIT_FAILURE );
}
if (solver->isProvenPrimalInfeasible())
{
fprintf( stderr, "LP solver says PRIMAL INFEASIBLE.\n" );
exit( EXIT_FAILURE );
}
if (solver->isProvenDualInfeasible())
{
fprintf( stderr, "LP solver says DUAL INFEASIBLE.\n" );
exit( EXIT_FAILURE );
}
if (solver->isPrimalObjectiveLimitReached())
{
fprintf( stderr, "LP solver says isPrimalObjectiveLimitReached.\n" );
exit( EXIT_FAILURE );
}
if (solver->isDualObjectiveLimitReached())
{
fprintf( stderr, "LP solver says isDualObjectiveLimitReached.\n" );
exit( EXIT_FAILURE );
}
if (solver->isIterationLimitReached())
{
fprintf( stderr, "LP solver says isIterationLimitReached.\n" );
exit( EXIT_FAILURE );
}
fprintf( stderr, "ERROR: Could not solve LP relaxation to optimality. Checking status...\n" );
exit( EXIT_FAILURE );
}
double initialBound = solver->getObjValue();
printf("%.2lf %d %d %.7lf", ((double)(clock()-start)) / ((double)CLOCKS_PER_SEC), pass, 0, solver->getObjValue());
if(!optFile.empty())
{
printf(" %.7lf %.7lf", opt, abs_mip_gap(solver->getObjValue(), opt));
}
printf("\n");
do
{
clock_t startSep = clock();
newCuts = 0;
switch (sepMethod)
{
case Npsep:
{
CglEClique cliqueGen;
OsiCuts cuts;
CglTreeInfo info;
info.level = 0;
info.pass = 1;
vector<string> varNames = getVarNames(solver->getColNames(), numCols);
cliqueGen.parseParameters( argc, (const char**)argv );
cliqueGen.setCGraph( cgraph );
cliqueGen.setGenOddHoles( true ); //allow (or not) inserting odd hole cuts
cliqueGen.colNames = &varNames;
cliqueGen.generateCuts( *solver, cuts, info );
newCuts = cuts.sizeCuts();
solver->applyCuts( cuts );
}
break;
case CglSepM:
{
CglClique cliqueGen;
OsiCuts cuts;
CglTreeInfo info;
info.level = 0;
info.pass = 1;
cliqueGen.setMinViolation( MIN_VIOLATION );
cliqueGen.setStarCliqueReport(false);
cliqueGen.setRowCliqueReport(false);
cliqueGen.generateCuts( *solver, cuts, info );
newCuts = cuts.sizeCuts();
solver->applyCuts( cuts );
}
break;
Default:
{
fprintf( stderr, "Separation Method does not recognized!\n" );
exit( EXIT_FAILURE );
}
}
pTime = ((double)(clock()-start)) / ((double)CLOCKS_PER_SEC);
if(pTime > MAX_TIME) break;
totalCuts += newCuts;
++pass;
if (newCuts)
{
solver->resolve();
if (!solver->isProvenOptimal())
{
if (solver->isAbandoned())
{
fprintf( stderr, "LP solver abandoned due to numerical dificulties.\n" );
exit( EXIT_FAILURE );
}
if (solver->isProvenPrimalInfeasible())
{
fprintf( stderr, "LP solver says PRIMAL INFEASIBLE.\n" );
exit( EXIT_FAILURE );
}
if (solver->isProvenDualInfeasible())
{
fprintf( stderr, "LP solver says DUAL INFEASIBLE.\n" );
exit( EXIT_FAILURE );
}
if (solver->isPrimalObjectiveLimitReached())
{
fprintf( stderr, "LP solver says isPrimalObjectiveLimitReached.\n" );
exit( EXIT_FAILURE );
}
if (solver->isDualObjectiveLimitReached())
{
fprintf( stderr, "LP solver says isDualObjectiveLimitReached.\n" );
exit( EXIT_FAILURE );
}
if (solver->isIterationLimitReached())
{
fprintf( stderr, "LP solver says isIterationLimitReached.\n" );
exit( EXIT_FAILURE );
}
fprintf( stderr, "ERROR: Could not solve LP relaxation. Exiting.\n" );
exit( EXIT_FAILURE );
}
pTime = ((double)(clock()-start)) / ((double)CLOCKS_PER_SEC);
if(pTime > MAX_TIME) break;
double sepTime = ((double)(clock()-startSep)) / ((double)CLOCKS_PER_SEC);
printf("%.2lf %d %d %.7lf", sepTime, pass, newCuts, solver->getObjValue());
if(!optFile.empty())
printf(" %.7lf %.7lf", opt, abs_mip_gap(solver->getObjValue(), opt));
printf("\n");
}
}
while ( (newCuts>0) && (pass<MAX_PASSES) ) ;
if(log)
{
double totalTime = ((double)(clock()-start)) / ((double)CLOCKS_PER_SEC);
fprintf(log, "%s %.2lf %d %d %.7lf", problemName, totalTime, pass - 1, totalCuts, solver->getObjValue());
if(!optFile.empty())
fprintf(log, " %.7lf", abs_mip_gap(solver->getObjValue(), opt));
fprintf(log, "\n");
}
if(cgraph)
cgraph_free( &cgraph );
delete realSolver;
return EXIT_SUCCESS;
}
/* After a CbcModel::resolve this can return a status
-1 no effect
0 treat as optimal
1 as 0 but do not do any more resolves (i.e. no more cuts)
2 treat as infeasible
*/
int
CbcNlpStrategy::status(CbcModel * model, CbcNodeInfo * parent,int whereFrom)
{
OsiSolverInterface * solver = model->solver();//get solver
int feasible = 1;
bool solved = true;
int returnStatus = -1;
BonCbcPartialNodeInfo * bmNodeInfo = dynamic_cast<BonCbcPartialNodeInfo *>(parent);
if (!bmNodeInfo) return -1;
int seqOfInfeasiblesSize = bmNodeInfo->getSequenceOfInfeasiblesSize();
int seqOfUnsolvedSize = bmNodeInfo->getSequenceOfUnsolvedSize();
if (solver->isAbandoned()) {
solved = false;
seqOfUnsolvedSize++;
;
}
else if (solver->isProvenPrimalInfeasible()) {
feasible = 0;
seqOfInfeasiblesSize++;
}
if ((seqOfUnsolvedSize==0) || (maxFailure_ == 0) &&
(maxInfeasible_== 0) || (seqOfInfeasiblesSize==0))
if (feasible && seqOfInfeasiblesSize > 1) {
(*model->messageHandler())<<"Feasible node while father was infeasible."
<<CoinMessageEol;
}
if (solved && seqOfUnsolvedSize > 1) {
(*model->messageHandler())<<"Solved node while father was unsolved."
<<CoinMessageEol;
}
if (seqOfInfeasiblesSize < maxInfeasible_ &&
solved && !feasible) {
(*model->messageHandler())<<"Branching on infeasible node, sequence of infeasibles size "
<<seqOfInfeasiblesSize<<CoinMessageEol;
// Have to make sure that we will branch
OsiTMINLPInterface * ipopt = dynamic_cast<OsiTMINLPInterface *>(solver);
ipopt->forceBranchable();
//change objective value
returnStatus = 0;
}
if (!solved && parent != NULL &&
seqOfUnsolvedSize <= maxFailure_) {
(*model->messageHandler())<<"Branching on unsolved node, sequence of unsolved size "<<seqOfUnsolvedSize<<CoinMessageEol;
// Have to make sure that we will branch
OsiTMINLPInterface * osiMinlp = dynamic_cast<OsiTMINLPInterface *>(solver);
osiMinlp->forceBranchable(); // feasible=1;
returnStatus = 0;
}
if (solver->isAbandoned() && parent != NULL &&
seqOfUnsolvedSize > maxFailure_) {
hasFailed_ = true;
OsiTMINLPInterface * osiMinlp =
dynamic_cast<OsiTMINLPInterface *>(solver);
if (pretendFailIsInfeasible_) {
//force infeasible
osiMinlp->forceInfeasible();
returnStatus = 2;
}
else {
std::string probName;
osiMinlp->getStrParam(OsiProbName,probName);
throw osiMinlp->newUnsolvedError(0, osiMinlp->problem(), probName);
}
}
return returnStatus;
}
TNLPSolver::ReturnStatus LpBranchingSolver::
solveFromHotStart(OsiTMINLPInterface* tminlp_interface)
{
TNLPSolver::ReturnStatus retstatus = TNLPSolver::solvedOptimal;
// updated the bounds of the linear solver
std::vector<int> diff_low_bnd_index;
std::vector<double> diff_low_bnd_value;
std::vector<int> diff_up_bnd_index;
std::vector<double> diff_up_bnd_value;
// Get the bounds. We assume that the bounds in the linear solver
// are always the original ones
const int numCols = tminlp_interface->getNumCols();
const double* colLow_orig = lin_->getColLower();
const double* colUp_orig = lin_->getColUpper();
const double* colLow = tminlp_interface->getColLower();
const double* colUp = tminlp_interface->getColUpper();
OsiSolverInterface * lin = lin_;
// eventualy clone lin_
if(warm_start_mode_ == Clone){
lin = lin_->clone();
// std::cout<<"Cloning it"<<std::endl;
}
// Set the bounds on the LP solver according to the changes in
// tminlp_interface
for (int i=0; i<numCols; i++) {
const double& lo = colLow[i];
if (colLow_orig[i] < lo) {
if(warm_start_mode_ == Basis){
diff_low_bnd_value.push_back(colLow_orig[i]);
diff_low_bnd_index.push_back(i);
}
lin->setColLower(i,lo);
}
const double& up = colUp[i];
if (colUp_orig[i] > up) {
if(warm_start_mode_ == Basis){
diff_up_bnd_index.push_back(i);
diff_up_bnd_value.push_back(colUp_orig[i]);
}
lin->setColUpper(i,lo);
}
}
if(warm_start_mode_ == Basis){
lin->setWarmStart(warm_);
}
lin->resolve();
double obj = lin->getObjValue();
bool go_on = true;
if (lin->isProvenPrimalInfeasible() ||
lin->isDualObjectiveLimitReached()) {
retstatus = TNLPSolver::provenInfeasible;
go_on = false;
}
else if (lin->isIterationLimitReached()) {
retstatus = TNLPSolver::iterationLimit;
go_on = false;
}
else {
if (maxCuttingPlaneIterations_ > 0 && go_on) {
double violation;
obj = ecp_->doEcpRounds(*lin, true, &violation);
if (obj == COIN_DBL_MAX) {
retstatus = TNLPSolver::provenInfeasible;
}
else if (violation <= 1e-8) {
retstatus = TNLPSolver::solvedOptimal;
}
}
}
tminlp_interface->problem()->set_obj_value(obj);
tminlp_interface->problem()->Set_x_sol(numCols, lin_->getColSolution());
//restore the original bounds
if(warm_start_mode_ == Basis){
for (unsigned int i = 0; i < diff_low_bnd_index.size(); i++) {
lin_->setColLower(diff_low_bnd_index[i],diff_low_bnd_value[i]);
}
for (unsigned int i = 0; i < diff_up_bnd_index.size(); i++) {
lin_->setColUpper(diff_up_bnd_index[i],diff_up_bnd_value[i]);
}
}
else {
delete lin;
}
return retstatus;
}
// mex function usage:
// [x,y,status] = mexosi(n_vars,n_cons,A,x_lb,x_ub,c,Ax_lb,Ax_ub,isMIP,isQP,vartype,Q,options)
// 0 1 2 3 4 5 6 7 8 9 10 11 12
void mexFunction(int nlhs, mxArray *plhs[],int nrhs, const mxArray *prhs[])
{
// Enable printing in MATLAB
int loglevel = 0;
DerivedHandler *mexprinter = new DerivedHandler(); // assumed open
mexprinter->setLogLevel(loglevel);
// check that we have the right number of inputs
if(nrhs < 10) mexErrMsgTxt("At least 10 inputs required in call to mexosi. Bug in osi.m?...");
// check that we have the right number of outputs
if(nlhs < 3) mexErrMsgTxt("At least 3 ouptuts required in call to mexosi. Bug in osi.m?...");
// Get pointers to input values
const int n_vars = (int)*mxGetPr(prhs[0]);
const int n_cons = (int)*mxGetPr(prhs[1]);
const mxArray *A = prhs[2];
const double *x_lb = mxGetPr(prhs[3]);
const double *x_ub = mxGetPr(prhs[4]);
const double *c = mxGetPr(prhs[5]);
const double *Ax_lb = mxGetPr(prhs[6]);
const double *Ax_ub = mxGetPr(prhs[7]);
const bool isMIP = (bool)*(mxLogical*)mxGetData(prhs[8]);
const bool isQP = (bool)*(mxLogical*)mxGetData(prhs[9]);
mxLogical *isinteger = (mxLogical*)mxGetData(prhs[10]);
const mxArray* Q = prhs[11];
// process the options
int returnStatus = 0;
// extract row/col/value data from A
const mwIndex * A_col_starts = mxGetJc(A);
const mwIndex * A_row_index = mxGetIr(A);
const double * A_data = mxGetPr(A);
// figure out the number of non-zeros in A
int nnz = (int)(A_col_starts[n_vars] - A_col_starts[0]); // number of non-zeros
//mexPrintf("nnz = %d, n_vars = %d, n_cons = %d\n",nnz,n_vars,n_cons);
// we need to convert these into other types of indices for Coin to use them
std::vector<CoinBigIndex> A_col_starts_coin(A_col_starts,A_col_starts+n_vars+1);
std::vector<int> A_row_index_coin(A_row_index,A_row_index+nnz);
// declare the solver
OsiSolverInterface* pSolver;
// initialize the solver
if ( isMIP ) {
pSolver = new OsiCbcSolverInterface;
} else {
pSolver = new OsiClpSolverInterface;
}
// OsiCbcSolverInterface is deprecated and CbcModel should be used instead but don't
// know how to get that working with loadProblem.
// OsiCbcSolverInterface solver1;
// CbcModel model(solver1);
// CbcMain0(model);
// OsiSolverInterface * pSolver = model.solver();
if (nrhs>12) { // get stuff out of the options structure if provided
// Finish me
}
// mexPrintf("Setting Log Level to 0.\n");
// load the problem
mexPrintf("Loading the problem.\n");
pSolver->loadProblem( n_vars, n_cons, // problem size
&A_col_starts_coin[0], &A_row_index_coin[0], A_data, // the A matrix
x_lb, x_ub, c, // the objective and bounds
Ax_lb, Ax_ub ); // the constraint bounds
// pSolver->messageHandler()->setLogLevel(0); // This doesn't seem to work
pSolver->setHintParam(OsiDoReducePrint,true,OsiHintTry);
// deal with integer inputs
if ( isMIP ) {
for(int i=0;i<n_vars;i++) {
if (isinteger[i]) pSolver->setInteger(i);
}
}
if (isQP) {
error("QP is not working yet");
// need to call loadQuadraticObjective here ???
}
// CbcModel model(pSolver);
// model.solver()->setHintParam(OsiDoReducePrint,true,OsiHintTry);
// solve the problem
//mexPrintf("Trying to solve the problem.\n");
if (isMIP) {
pSolver->branchAndBound();
// model.branchAndBound();
} else {
// model.initialSolve();
pSolver->initialSolve();
}
// Allocate memory for return data
plhs[0] = mxCreateDoubleMatrix(n_vars,1, mxREAL); // for the solution
plhs[1] = mxCreateDoubleMatrix(n_cons,1, mxREAL); // for the constraint prices
plhs[2] = mxCreateDoubleMatrix(1,1, mxREAL); // for the return status
double *x = mxGetPr(plhs[0]);
double *y = mxGetPr(plhs[1]);
double *returncode = mxGetPr(plhs[2]);
// Copy solutions if available
if ( pSolver->isProvenOptimal() ) {
// if ( model.isProvenOptimal() ) {
// if ( model.solver()->isProvenOptimal() ) {
//mexPrintf("Solution found.\n");
// extract the solutions
const double * solution = pSolver->getColSolution();
const double * dualvars = pSolver->getRowPrice();
// copy the solution to the outpus
memcpy(x,solution,n_vars*sizeof(double));
memcpy(y,dualvars,n_cons*sizeof(double));
*returncode = 1;
} else {
if ( pSolver->isProvenPrimalInfeasible() ) {
mexPrintf("Primal problem is proven infeasible.\n");
*returncode = 0;
} else if ( pSolver->isProvenDualInfeasible() ) {
mexPrintf("Dual problem is proven infeasible.\n");
*returncode = -1;
} else if ( pSolver->isPrimalObjectiveLimitReached() ) {
mexPrintf("The primal objective limit was reached.\n");
*returncode = -2;
} else if ( pSolver->isDualObjectiveLimitReached() ) {
mexPrintf("The dual objective limit was reached.\n");
*returncode = -3;
} else if ( pSolver->isIterationLimitReached() ) {
mexPrintf("The iteration limit was reached\n");
*returncode = -4;
}
}
// clean up memory
if ( mexprinter!= NULL) delete mexprinter;
delete pSolver;
}
//Solver function
int sci_rmps(char *fname)
{
//creating a problem pointer using base class of OsiSolverInterface and
//instantiate the object using derived class of ClpSolverInterface
OsiSolverInterface* si = new OsiClpSolverInterface();
// Error management variable
SciErr sciErr;
//data declarations
int *piAddressVarOne = NULL; //pointer used to access argument of the function
char* ptr; //pointer to point to address of file name
double* options_; //options to set maximum iterations
CheckInputArgument(pvApiCtx, 2,2 ); //Check we have exactly two arguments as input or not
CheckOutputArgument(pvApiCtx, 6, 6); //Check we have exactly six arguments on output side or not
//Getting the input arguments from Scilab
//Getting the MPS file path
//Reading mps file
getStringFromScilab(1,&ptr);
std::cout<<ptr;
//get options from Scilab
if(getFixedSizeDoubleMatrixInList(2 , 2 , 1 , 1 , &options_))
{
return 1;
}
//Read the MPS file
si->readMps(ptr);
//setting options for maximum iterations
si->setIntParam(OsiMaxNumIteration,options_[0]);
//Solve the problem
si->initialSolve();
//Quering about the problem
//get number of variables
double numVars_;
numVars_ = si->getNumCols();
//get number of constraint equations
double numCons_;
numCons_ = si->getNumRows();
//Output the solution to Scilab
//get solution for x
const double* xValue = si->getColSolution();
//get objective value
double objValue = si->getObjValue();
//get Status value
double status;
if(si->isProvenOptimal())
status=0;
else if(si->isProvenPrimalInfeasible())
status=1;
else if(si->isProvenDualInfeasible())
status=2;
else if(si->isIterationLimitReached())
status=3;
else if(si->isAbandoned())
status=4;
else if(si->isPrimalObjectiveLimitReached())
status=5;
else if(si->isDualObjectiveLimitReached())
status=6;
//get number of iterations
double iterations = si->getIterationCount();
//get reduced cost
const double* reducedCost = si->getReducedCost();
//get dual vector
const double* dual = si->getRowPrice();
returnDoubleMatrixToScilab(1 , 1 , numVars_ , xValue);
returnDoubleMatrixToScilab(2 , 1 , 1 , &objValue);
returnDoubleMatrixToScilab(3 , 1 , 1 , &status);
returnDoubleMatrixToScilab(4 , 1 , 1 , &iterations);
returnDoubleMatrixToScilab(5 , 1 , numVars_ , reducedCost);
returnDoubleMatrixToScilab(6 , 1 , numCons_ , dual);
free(xValue);
free(dual);
free(reducedCost);
}
