/* Choose a variable Returns - -1 Node is infeasible 0 Normal termination - we have a candidate 1 All looks satisfied - no candidate 2 We can change the bound on a variable - but we also have a strong branching candidate 3 We can change the bound on a variable - but we have a non-strong branching candidate 4 We can change the bound on a variable - no other candidates We can pick up branch from whichObject() and whichWay() We can pick up a forced branch (can change bound) from whichForcedObject() and whichForcedWay() If we have a solution then we can pick up from goodObjectiveValue() and goodSolution() */ int BonNWayChoose::chooseVariable( OsiSolverInterface * solver, OsiBranchingInformation *info, bool fixVariables) { if(!numberUnsatisfied_) return 1;//Node is feasible double cutoff = info->cutoff_; double obj_val = info->objectiveValue_; if(info->depth_ > br_depth_ && ( (- useful_[0] > pseudocost_trust_value_ )|| num_eval_[list_[0] - start_nway_] >= 18) ){ const double * lower = info->lower_; const double * upper = info->upper_; // See if quick variable fixing can be done int n_fixed = 0; if(do_fixings_ > 1){ for(int i = 0 ; i < numberUnsatisfied_ ; i++){ int iObject = list_[i]; int nwayIndex = iObject - start_nway_; const BonNWayObject * nway = ASSERTED_CAST<const BonNWayObject *>(solver->object(iObject)); size_t n = nway->numberMembers(); const int * vars = nway->members(); for(size_t j = 0 ; j < n ; j++){ int iCol = vars[j]; if(upper[iCol] < lower[iCol] + 0.5) continue;//variable already fixed to lower buund if(bounds_[nwayIndex][j] > cutoff){//It can be fixed solver->setColUpper(iCol, lower[iCol]); n_fixed ++; } } } if(n_fixed && log_ > 1) printf("NWAY: Fixed %i variables\n", n_fixed); } assert(bounds_.size() == unit_changes_.size()); assert(unit_changes_.size() == info->solver_->numberObjects() - start_nway_); //Just take the most usefull bestObjectIndex_ = list_[0]; bestWhichWay_ = 1; OsiObject * obj = solver->objects()[bestObjectIndex_]; obj->setWhichWay(bestWhichWay_); if(log_ > 1){ printf("level %i branch on %i bound %g usefullness %g.\n", info->depth_, bestObjectIndex_ - start_nway_, obj_val, - useful_[0]); } if(n_fixed) return 2; return 0; } if(log_ > 0) printf("Restarting strong branching loop....\n\n"); numberStrongIterations_ = 0; numberStrongDone_ = 0; int numberLeft = numberOnList_;//Always do full strong at root int returnCode=0; bestObjectIndex_ = -1; bestWhichWay_ = -1; firstForcedObjectIndex_ = -1; firstForcedWhichWay_ =-1; double best_score = -COIN_DBL_MAX; int bestPriority=0; int n = solver->getNumCols(); std::vector<double> saveLower(n); std::vector<double> saveUpper(n); std::copy(info->lower_, info->lower_ + n, saveLower.begin()); std::copy(info->upper_, info->upper_ + n, saveUpper.begin()); solver->markHotStart(); for (int i=0;i<numberLeft;i++) { int iObject = list_[i]; const int objectPriority = solver->object(iObject)->priority(); if (objectPriority >= bestPriority){ bestPriority = objectPriority; } else break; double score; int r_val = doStrongBranching(solver, info, iObject, saveLower.data(), saveUpper.data(), score); if(r_val == -1) { if(log_ > 0) std::cout<<"This is Infeasible"<<std::endl; returnCode = -1; break; } if(do_fixings_ > 1 && r_val == 1 && info->depth_ == 0) returnCode=2; //Compute Score if(log_ > 0) printf("Usefullness from strong branching on %i : %g\n", iObject - start_nway_, score); if(score > best_score){//We have a winner best_score = score; bestObjectIndex_ = iObject; bestWhichWay_ = 0; } if (r_val==3) { returnCode = 3; // max time - just choose one if(bestObjectIndex_ < 0){ bestObjectIndex_ = list_[0]; bestWhichWay_ = 0; } break; } } solver->unmarkHotStart(); return returnCode; }
/** Perform a branch-and-bound on given setup.*/ void CouenneBab::branchAndBound (Bonmin::BabSetupBase & s) { double remaining_time = s.getDoubleParameter(Bonmin::BabSetupBase::MaxTime) + CoinCpuTime(); /* Put a link to this into solver.*/ OsiBabSolver * babInfo = dynamic_cast<OsiBabSolver *>(s.continuousSolver()->getAuxiliaryInfo()); assert(babInfo); Bonmin::BabInfo * bonBabInfoPtr = dynamic_cast<Bonmin::BabInfo*>(babInfo); if (bonBabInfoPtr == NULL) { //Replace with a Bonmin::babInfo bonBabInfoPtr = new Bonmin::BabInfo(*babInfo); s.continuousSolver()->setAuxiliaryInfo(bonBabInfoPtr); delete bonBabInfoPtr; bonBabInfoPtr = dynamic_cast<Bonmin::BabInfo*>(s.continuousSolver()->getAuxiliaryInfo()); } bonBabInfoPtr->setBabPtr(this); s.nonlinearSolver()->solver()->setup_global_time_limit(s.getDoubleParameter(Bonmin::BabSetupBase::MaxTime)); OsiSolverInterface * solver = s.continuousSolver()->clone(); delete modelHandler_; modelHandler_ = s.continuousSolver()->messageHandler()->clone(); model_.passInMessageHandler(modelHandler_); model_.assignSolver(solver, true); // s.continuousSolver() = model_.solver(); // if(s.continuousSolver()->objects()!=NULL){ // model_.addObjects(s.continuousSolver()->numberObjects(),s.continuousSolver()->objects()); // } int specOpt = s.getIntParameter(Bonmin::BabSetupBase::SpecialOption); if (specOpt) { model_.setSpecialOptions(specOpt); if (specOpt==16) { Bonmin::CbcNlpStrategy strat(s.getIntParameter(Bonmin::BabSetupBase::MaxFailures), s.getIntParameter(Bonmin::BabSetupBase::MaxInfeasible), s.getIntParameter(Bonmin::BabSetupBase::FailureBehavior)); model_.setStrategy(strat); } } model_.setMaximumCutPasses(s.getIntParameter(Bonmin::BabSetupBase::NumCutPasses)); model_.setMaximumCutPassesAtRoot(s.getIntParameter(Bonmin::BabSetupBase::NumCutPassesAtRoot)); //Setup cutting plane methods for (Bonmin::BabSetupBase::CuttingMethods::iterator i = s.cutGenerators().begin() ; i != s.cutGenerators().end() ; i++) { Bonmin::OaDecompositionBase * oa = dynamic_cast<Bonmin::OaDecompositionBase *>(i->cgl); if (oa && oa->reassignLpsolver()) oa->assignLpInterface(model_.solver()); model_.addCutGenerator(i->cgl,i->frequency,i->id.c_str(), i->normal, i->atSolution); if(i->always){ model_.cutGenerators()[model_.numberCutGenerators()-1] ->setMustCallAgain(true); } } for (Bonmin::BabSetupBase::HeuristicMethods::iterator i = s.heuristics().begin() ; i != s.heuristics().end() ; i++) { CbcHeuristic * heu = i->heuristic; heu->setModel(&model_); model_.addHeuristic(heu, i->id.c_str()); } //need to record solver logLevel here int logLevel = s.continuousSolver()->messageHandler()->logLevel(); //Set true branch-and-bound parameters model_.setLogLevel(s.getIntParameter(Bonmin::BabSetupBase::BabLogLevel)); // Put back solver logLevel model_.solver()->messageHandler()->setLogLevel(logLevel); model_.setPrintFrequency(s.getIntParameter(Bonmin::BabSetupBase::BabLogInterval)); bool ChangedObject = false; //Pass over user set branching priorities to Cbc if (s.continuousSolver()->objects()==NULL) { //assert (s.branchingMethod() == NULL); const OsiTMINLPInterface * nlpSolver = s.nonlinearSolver(); //set priorities, prefered directions... const int * priorities = nlpSolver->getPriorities(); const double * upPsCosts = nlpSolver->getUpPsCosts(); const double * downPsCosts = nlpSolver->getDownPsCosts(); const int * directions = nlpSolver->getBranchingDirections(); bool hasPseudo = (upPsCosts!=NULL); model_.findIntegers(true,hasPseudo); OsiObject ** simpleIntegerObjects = model_.objects(); int numberObjects = model_.numberObjects(); if (priorities != NULL || directions != NULL || hasPseudo) { ChangedObject = true; for (int i = 0 ; i < numberObjects ; i++) { CbcObject * object = dynamic_cast<CbcObject *> (simpleIntegerObjects[i]); int iCol = object->columnNumber(); if (priorities) object->setPriority(priorities[iCol]); if (directions) object->setPreferredWay(directions[iCol]); if (upPsCosts) { CbcSimpleIntegerPseudoCost * pscObject = dynamic_cast<CbcSimpleIntegerPseudoCost*> (object); pscObject->setUpPseudoCost(upPsCosts[iCol]); pscObject->setDownPseudoCost(downPsCosts[iCol]); } } } #if 1 // Now pass user set Sos constraints (code inspired from CoinSolve.cpp) const TMINLP::SosInfo * sos = s.nonlinearSolver()->model()->sosConstraints(); if (!s.getIntParameter(Bonmin::BabSetupBase::DisableSos) && sos && sos->num > 0) { // we have some sos constraints const OsiTMINLPInterface * nlpSolver = s.nonlinearSolver(); const int & numSos = sos->num; (*nlpSolver->messageHandler())<<"Adding "<<sos->num<<" sos constraints." <<CoinMessageEol; CbcObject ** objects = new CbcObject*[numSos]; const int * starts = sos->starts; const int * indices = sos->indices; const char * types = sos->types; const double * weights = sos->weights; //verify if model has user set priorities bool hasPriorities = false; const int * varPriorities = nlpSolver->getPriorities(); int numberObjects = model_.numberObjects(); if (varPriorities) { for (int i = 0 ; i < numberObjects ; i++) { if (varPriorities[i]) { hasPriorities = true; break; } } } const int * sosPriorities = sos->priorities; if (sosPriorities) { for (int i = 0 ; i < numSos ; i++) { if (sosPriorities[i]) { hasPriorities = true; break; } } } for (int i = 0 ; i < numSos ; i++) { int start = starts[i]; int length = starts[i + 1] - start; #ifdef DO_IT_NWAY printf("setting nway object\n"), objects[i] = new CbcNWay(&model_, length, &indices[start], i); objects[i]->setPriority(1); #else objects[i] = new CbcSOS(&model_, length, &indices[start], &weights[start], i, types[i]); objects[i]->setPriority(10); #endif if (hasPriorities && sosPriorities && sosPriorities[i]) { objects[i]->setPriority(sosPriorities[i]); } } model_.addObjects (numSos, objects); for (int i = 0 ; i < numSos ; i++) delete objects[i]; delete [] objects; } #endif //If Setup contains more objects add them to Cbc if (s.objects().size()) { CbcObject ** objects = new CbcObject *[s.objects().size()]; for (unsigned int i = 0 ; i < s.objects().size() ; i++) { objects[i] = dynamic_cast<CbcObject *> (s.objects()[i]); assert(objects[i]); objects[i]->setModel(&model_); } model_.addObjects ((int) s.objects().size(), objects); delete [] objects; } replaceIntegers(model_.objects(), model_.numberObjects()); } else { // Pass in objects to Cbc // Redundant definition of default branching (as Default == User) assert (s.branchingMethod() != NULL); // Add nonlinear and integer objects (need to add OsiSOS) model_.addObjects (s.continuousSolver () -> numberObjects (), s.continuousSolver () -> objects ()); // Now model_ has only CouenneObjects and SOS objects // for (int i=0; i<nco; i++) // if (!(dynamic_cast <CbcSimpleInteger *> (s.continuousSolver () -> objects () [i]))) // model_ . objects () [nRealObj++] = s.continuousSolver () -> objects () [i] -> clone (); CbcBranchDefaultDecision branch; s.branchingMethod()->setSolver(model_.solver()); BonChooseVariable * strong2 = dynamic_cast<BonChooseVariable *>(s.branchingMethod()); if (strong2) strong2->setCbcModel(&model_); branch.setChooseMethod(*s.branchingMethod()); model_.setBranchingMethod(&branch); // prevent duplicating object when copying in CbcModel.cpp model_.solver()->deleteObjects(); } model_.setDblParam(CbcModel::CbcCutoffIncrement, s.getDoubleParameter(Bonmin::BabSetupBase::CutoffDecr)); model_.setCutoff(s.getDoubleParameter(Bonmin::BabSetupBase::Cutoff) + CUTOFF_TOL); model_.setDblParam(CbcModel::CbcAllowableGap, s.getDoubleParameter(Bonmin::BabSetupBase::AllowableGap)); model_.setDblParam(CbcModel::CbcAllowableFractionGap, s.getDoubleParameter(Bonmin::BabSetupBase::AllowableFractionGap)); // Definition of node selection strategy if (s.nodeComparisonMethod()==Bonmin::BabSetupBase::bestBound) { CbcCompareObjective compare; model_.setNodeComparison(compare); } else if (s.nodeComparisonMethod()==Bonmin::BabSetupBase::DFS) { CbcCompareDepth compare; model_.setNodeComparison(compare); } else if (s.nodeComparisonMethod()==Bonmin::BabSetupBase::BFS) { CbcCompareDefault compare; compare.setWeight(0.0); model_.setNodeComparison(compare); } else if (s.nodeComparisonMethod()==Bonmin::BabSetupBase::dynamic) { CbcCompareDefault compare; model_.setNodeComparison(compare); } else if (s.nodeComparisonMethod()==Bonmin::BabSetupBase::bestGuess) { // Right now, this is a mess. We need a separation of the // pseudo costs from the ChooseVariable method CbcCompareEstimate compare; model_.setNodeComparison(compare); GuessHeuristic * guessHeu = new GuessHeuristic(model_); model_.addHeuristic(guessHeu); delete guessHeu; } if (s.treeTraversalMethod() == Bonmin::BabSetupBase::HeapOnly) { //Do nothing this is the default of Cbc. } else if (s.treeTraversalMethod() == Bonmin::BabSetupBase::DiveFromBest) { CbcDiver treeTraversal; treeTraversal.initialize(s); model_.passInTreeHandler(treeTraversal); } else if (s.treeTraversalMethod() == Bonmin::BabSetupBase::ProbedDive) { CbcProbedDiver treeTraversal; treeTraversal.initialize(s); model_.passInTreeHandler(treeTraversal); } else if (s.treeTraversalMethod() == Bonmin::BabSetupBase::DfsDiveFromBest) { CbcDfsDiver treeTraversal; treeTraversal.initialize(s); model_.passInTreeHandler(treeTraversal); } else if (s.treeTraversalMethod() == Bonmin::BabSetupBase::DfsDiveDynamic) { CbcDfsDiver treeTraversal; treeTraversal.initialize(s); model_.passInTreeHandler(treeTraversal); DiverCompare compare; compare.setComparisonDive(*model_.nodeComparison()); compare.setComparisonBound(CbcCompareObjective()); CbcDfsDiver * dfs = dynamic_cast<CbcDfsDiver *> (model_.tree()); assert(dfs); compare.setDiver(dfs); model_.setNodeComparison(compare); } model_.setNumberStrong(s.getIntParameter(Bonmin::BabSetupBase::NumberStrong)); model_.setNumberBeforeTrust(s.getIntParameter(Bonmin::BabSetupBase::MinReliability)); model_.setNumberPenalties(8); model_.setDblParam(CbcModel::CbcMaximumSeconds, s.getDoubleParameter(Bonmin::BabSetupBase::MaxTime)); model_.setMaximumNodes(s.getIntParameter(Bonmin::BabSetupBase::MaxNodes)); model_.setMaximumNumberIterations(s.getIntParameter(Bonmin::BabSetupBase::MaxIterations)); model_.setMaximumSolutions(s.getIntParameter(Bonmin::BabSetupBase::MaxSolutions)); model_.setIntegerTolerance(s.getDoubleParameter(Bonmin::BabSetupBase::IntTol)); //Get objects from model_ if it is not null means there are some sos constraints or non-integer branching object // pass them to cut generators. OsiObject ** objects = model_.objects(); if (specOpt!=16 && objects) { int numberObjects = model_.numberObjects(); if (objects_ != NULL) { for (int i = 0 ; i < nObjects_; i++) delete objects_[i]; } delete [] objects_; objects_ = new OsiObject*[numberObjects]; nObjects_ = numberObjects; for (int i = 0 ; i < numberObjects; i++) { OsiObject * obj = objects[i]; CbcSimpleInteger * intObj = dynamic_cast<CbcSimpleInteger *> (obj); if (intObj) { objects_[i] = intObj->osiObject(); } else { CbcSOS * sosObj = dynamic_cast<CbcSOS *>(obj); if (sosObj) objects_[i] = sosObj->osiObject(model_.solver()); else {//Maybe an unsupported CbcObject CbcObject * cbcObj = dynamic_cast<CbcObject *>(obj); if (cbcObj) { std::cerr<<"Unsupported CbcObject appears in the code"<<std::endl; throw UNSUPPORTED_CBC_OBJECT; } else {//It has to be an OsiObject. objects_[i]=obj->clone(); } } } } CbcCutGenerator ** gen = model_.cutGenerators(); int numGen = model_.numberCutGenerators(); for (int i = 0 ; i < numGen ; i++) { Bonmin::OaDecompositionBase * oa = dynamic_cast<Bonmin::OaDecompositionBase * >(gen[i]->generator()); // if (oa) // printf ("\n\n\nat least one OADecompBase\n\n\n"); if (oa) // pass objects oa->setObjects(objects_,nObjects_); } } // if (objects_) { // for (int i = 0 ; i < nObjects_; i++) // delete objects_ [i]; // delete [] objects_; // } // OsiObject ** objects = model_.objects(); // int numObjects = model_.numberObjects(); // nObjects_ = 0; // objects_ = new OsiObject* [numObjects]; // for (int i=0; i < numObjects; ++i) // if (objects [i]) // objects_ [nObjects_++] = objects [i] -> clone (); try { //Get the time and start. { OsiTMINLPInterface * tmpOsi = NULL; if(s.nonlinearSolver() == s.continuousSolver()){ tmpOsi = dynamic_cast<OsiTMINLPInterface *> (model_.solver()); tmpOsi->forceSolverOutput(s.getIntParameter(Bonmin::BabSetupBase::RootLogLevel)); } model_.initialSolve(); if(tmpOsi != NULL){ tmpOsi->setSolverOutputToDefault(); } } int ival; s.options()->GetEnumValue("enable_dynamic_nlp", ival, "bonmin."); if(s.nonlinearSolver() == s.continuousSolver() && ival) { if(!model_.solver()->isProvenOptimal() ){//Something went wrong check if objective is linear and alternate model // can be solved OsiTMINLPInterface * tmpOsi = dynamic_cast<OsiTMINLPInterface *> (model_.solver()); TMINLPLinObj * tmp_tminlp = dynamic_cast<TMINLPLinObj *> (tmpOsi->model()); tmpOsi->setModel(tmp_tminlp->tminlp()); model_.initialSolve(); } else { LinearCutsGenerator cgl; cgl.initialize(s); OsiCuts cuts; cgl.generateCuts(*model_.solver(), cuts); std::vector<const OsiRowCut *> mycuts(cuts.sizeRowCuts()); for(int i = 0 ; i < cuts.sizeRowCuts() ; i++){ mycuts[i] = cuts.rowCutPtr(i); } model_. solver () -> applyRowCuts ((int) mycuts.size(), (const OsiRowCut **) &mycuts[0]); } //Added by Claudia OsiTMINLPInterface * nlpSolver = dynamic_cast<OsiTMINLPInterface *>(model_.solver()); if(nlpSolver && nlpSolver->getNewCutoffDecr()!=COIN_DBL_MAX) model_.setDblParam(CbcModel::CbcCutoffIncrement, nlpSolver->getNewCutoffDecr()); model_.solver()->resolve(); } // for Couenne model_.passInSolverCharacteristics (bonBabInfoPtr); continuousRelaxation_ =model_.solver()->getObjValue(); if (specOpt==16)//Set warm start point for Ipopt { #if 1 const double * colsol = model_.solver()->getColSolution(); const double * duals = model_.solver()->getRowPrice(); OsiTMINLPInterface * tnlpSolver = dynamic_cast<OsiTMINLPInterface *>(model_.solver()); // Primal dual point is not copied if one (supposedly a better one) has already been put into the solver. if(tnlpSolver->problem()->has_x_init() != 2){ model_.solver()->setColSolution(colsol); model_.solver()->setRowPrice(duals); } #else OsiTMINLPInterface * tnlpSolver = dynamic_cast<OsiTMINLPInterface *>(model_.solver()); CoinWarmStart * warm = tnlpSolver->solver()->getWarmStart(tnlpSolver->problem()); tnlpSolver->solver()->setWarmStart(warm, tnlpSolver->problem()); delete warm; #endif #if 0 // Sometimes primal dual point is problematic in the context of Cut-and-branch model_.solver()->resolve(); if(!model_.solver()->isProvenOptimal()) model_.solver()->setColSolution(NULL); #endif } #ifdef SIGNAL CoinSighandler_t saveSignal = SIG_DFL; // register signal handler saveSignal = signal (SIGINT,couenne_signal_handler); currentBranchModel = &model_; #endif // to get node parent info in Cbc, pass parameter 3. //model_.branchAndBound(3); remaining_time -= CoinCpuTime(); model_.setDblParam(CbcModel::CbcMaximumSeconds, remaining_time); if(remaining_time > 0.) model_.branchAndBound(); } catch(TNLPSolver::UnsolvedError *E){ s.nonlinearSolver()->model()->finalize_solution (TMINLP::MINLP_ERROR, 0, NULL, DBL_MAX); throw E; } numNodes_ = model_.getNodeCount(); bestObj_ = model_.getObjValue(); bestBound_ = model_.getBestPossibleObjValue(); mipIterationCount_ = model_.getIterationCount(); bool hasFailed = false; if (specOpt==16)//Did we continue branching on a failure { CbcNlpStrategy * nlpStrategy = dynamic_cast<CbcNlpStrategy *>(model_.strategy()); if (nlpStrategy) hasFailed = nlpStrategy->hasFailed(); else throw -1; } else hasFailed = s.nonlinearSolver()->hasContinuedOnAFailure(); // Output summarizing cut generators (taken from CbcSolver.cpp) // ToDo put into proper print level int numberGenerators = model_.numberCutGenerators(); for (int iGenerator=0;iGenerator<numberGenerators;iGenerator++) { CbcCutGenerator * generator = model_.cutGenerator(iGenerator); //CglStored * stored = dynamic_cast<CglStored*>(generator->generator()); if (true&&!(generator->numberCutsInTotal() || generator->numberColumnCuts())) continue; if(modelHandler_->logLevel() >= 1) { *modelHandler_ << generator->cutGeneratorName() << "was tried" << generator->numberTimesEntered() << "times and created" << generator->numberCutsInTotal()+generator->numberColumnCuts() << "cuts of which" << generator->numberCutsActive() << "were active after adding rounds of cuts"; // if (generator->timing()) { // char timebuf[20]; // sprintf(timebuf, "(%.3fs)", generator->timeInCutGenerator()); // *modelHandler_ << timebuf << CoinMessageEol; // } // else { // *modelHandler_ << CoinMessageEol; // } } } TMINLP::SolverReturn status = TMINLP::MINLP_ERROR; if (model_.numberObjects()==0) { if (bestSolution_) delete [] bestSolution_; OsiSolverInterface * solver = (s.nonlinearSolver() == s.continuousSolver())? model_.solver() : s.nonlinearSolver(); bestSolution_ = new double[solver->getNumCols()]; CoinCopyN(solver->getColSolution(), solver->getNumCols(), bestSolution_); bestObj_ = bestBound_ = solver->getObjValue(); } if (bonBabInfoPtr->bestSolution2().size() > 0) { assert((int) bonBabInfoPtr->bestSolution2().size() == s.nonlinearSolver()->getNumCols()); if (bestSolution_) delete [] bestSolution_; bestSolution_ = new double[s.nonlinearSolver()->getNumCols()]; std::copy(bonBabInfoPtr->bestSolution2().begin(), bonBabInfoPtr->bestSolution2().end(), bestSolution_); bestObj_ = (bonBabInfoPtr->bestObj2()); (*s.nonlinearSolver()->messageHandler())<<"\nReal objective function: " <<bestObj_<<CoinMessageEol; } else if (model_.bestSolution()) { if (bestSolution_) delete [] bestSolution_; bestSolution_ = new double[s.nonlinearSolver()->getNumCols()]; CoinCopyN(model_.bestSolution(), s.nonlinearSolver()->getNumCols(), bestSolution_); } if(remaining_time <= 0.){ status = TMINLP::LIMIT_EXCEEDED; if (bestSolution_) { mipStatus_ = Feasible; } else { mipStatus_ = NoSolutionKnown; } } else if (model_.status() == 0) { if(model_.isContinuousUnbounded()){ status = TMINLP::CONTINUOUS_UNBOUNDED; mipStatus_ = UnboundedOrInfeasible; } else if (bestSolution_) { status = TMINLP::SUCCESS; mipStatus_ = FeasibleOptimal; } else { status = TMINLP::INFEASIBLE; mipStatus_ = ProvenInfeasible; } } else if (model_.status() == 1 || model_.status() == 5) { #if (BONMIN_VERSION_MAJOR > 1) || (BONMIN_VERSION_MINOR > 6) status = model_.status() == 1 ? TMINLP::LIMIT_EXCEEDED : TMINLP::USER_INTERRUPT; #else status = TMINLP::LIMIT_EXCEEDED; #endif if (bestSolution_) { mipStatus_ = Feasible; } else { mipStatus_ = NoSolutionKnown; } } else if (model_.status()==2) { status = TMINLP::MINLP_ERROR; } // Which solution should we use? false if RBS's, true if Cbc's bool use_RBS_Cbc = !problem_ || !(problem_ -> getRecordBestSol ()) || !(problem_ -> getRecordBestSol () -> getHasSol()) || (((fabs (bestObj_) < COUENNE_INFINITY / 1e4) && (problem_ -> getRecordBestSol () -> getVal () > bestObj_))); /* if we do not pass the cbc solution and problem_ -> getRecordBestSol () -> getHasSol() is true, then there should be a solution vector in problem_ -> getRecordBestSol () */ assert(use_RBS_Cbc || problem_ -> getRecordBestSol () -> getSol() != NULL); s.nonlinearSolver () -> model () -> finalize_solution (status, s.nonlinearSolver () -> getNumCols (), use_RBS_Cbc ? bestSolution_ : problem_ -> getRecordBestSol () -> getSol (), use_RBS_Cbc ? bestObj_ : problem_ -> getRecordBestSol () -> getVal ()); }
/* Choose a variable Returns - -1 Node is infeasible 0 Normal termination - we have a candidate 1 All looks satisfied - no candidate 2 We can change the bound on a variable - but we also have a strong branching candidate 3 We can change the bound on a variable - but we have a non-strong branching candidate 4 We can change the bound on a variable - no other candidates We can pick up branch from whichObject() and whichWay() We can pick up a forced branch (can change bound) from whichForcedObject() and whichForcedWay() If we have a solution then we can pick up from goodObjectiveValue() and goodSolution() */ int OsiChooseStrong::chooseVariable( OsiSolverInterface * solver, OsiBranchingInformation *info, bool fixVariables) { if (numberUnsatisfied_) { const double* upTotalChange = pseudoCosts_.upTotalChange(); const double* downTotalChange = pseudoCosts_.downTotalChange(); const int* upNumber = pseudoCosts_.upNumber(); const int* downNumber = pseudoCosts_.downNumber(); int numberBeforeTrusted = pseudoCosts_.numberBeforeTrusted(); // Somehow we can get here with it 0 ! if (!numberBeforeTrusted) { numberBeforeTrusted=5; pseudoCosts_.setNumberBeforeTrusted(numberBeforeTrusted); } int numberLeft = CoinMin(numberStrong_-numberStrongDone_,numberUnsatisfied_); int numberToDo=0; resetResults(numberLeft); int returnCode=0; bestObjectIndex_ = -1; bestWhichWay_ = -1; firstForcedObjectIndex_ = -1; firstForcedWhichWay_ =-1; double bestTrusted=-COIN_DBL_MAX; for (int i=0;i<numberLeft;i++) { int iObject = list_[i]; if (upNumber[iObject]<numberBeforeTrusted||downNumber[iObject]<numberBeforeTrusted) { results_[numberToDo++] = OsiHotInfo(solver, info, solver->objects(), iObject); } else { const OsiObject * obj = solver->object(iObject); double upEstimate = (upTotalChange[iObject]*obj->upEstimate())/upNumber[iObject]; double downEstimate = (downTotalChange[iObject]*obj->downEstimate())/downNumber[iObject]; double value = MAXMIN_CRITERION*CoinMin(upEstimate,downEstimate) + (1.0-MAXMIN_CRITERION)*CoinMax(upEstimate,downEstimate); if (value > bestTrusted) { bestObjectIndex_=iObject; bestWhichWay_ = upEstimate>downEstimate ? 0 : 1; bestTrusted = value; } } } int numberFixed=0; if (numberToDo) { returnCode = doStrongBranching(solver, info, numberToDo, 1); if (returnCode>=0&&returnCode<=2) { if (returnCode) { returnCode=4; if (bestObjectIndex_>=0) returnCode=3; } for (int i=0;i<numResults_;i++) { int iObject = results_[i].whichObject(); double upEstimate; if (results_[i].upStatus()!=1) { assert (results_[i].upStatus()>=0); upEstimate = results_[i].upChange(); } else { // infeasible - just say expensive if (info->cutoff_<1.0e50) upEstimate = 2.0*(info->cutoff_-info->objectiveValue_); else upEstimate = 2.0*fabs(info->objectiveValue_); if (firstForcedObjectIndex_ <0) { firstForcedObjectIndex_ = iObject; firstForcedWhichWay_ =0; } numberFixed++; if (fixVariables) { const OsiObject * obj = solver->object(iObject); OsiBranchingObject * branch = obj->createBranch(solver,info,0); branch->branch(solver); delete branch; } } double downEstimate; if (results_[i].downStatus()!=1) { assert (results_[i].downStatus()>=0); downEstimate = results_[i].downChange(); } else { // infeasible - just say expensive if (info->cutoff_<1.0e50) downEstimate = 2.0*(info->cutoff_-info->objectiveValue_); else downEstimate = 2.0*fabs(info->objectiveValue_); if (firstForcedObjectIndex_ <0) { firstForcedObjectIndex_ = iObject; firstForcedWhichWay_ =1; } numberFixed++; if (fixVariables) { const OsiObject * obj = solver->object(iObject); OsiBranchingObject * branch = obj->createBranch(solver,info,1); branch->branch(solver); delete branch; } } double value = MAXMIN_CRITERION*CoinMin(upEstimate,downEstimate) + (1.0-MAXMIN_CRITERION)*CoinMax(upEstimate,downEstimate); if (value>bestTrusted) { bestTrusted = value; bestObjectIndex_ = iObject; bestWhichWay_ = upEstimate>downEstimate ? 0 : 1; // but override if there is a preferred way const OsiObject * obj = solver->object(iObject); if (obj->preferredWay()>=0&&obj->infeasibility()) bestWhichWay_ = obj->preferredWay(); if (returnCode) returnCode=2; } } } else if (returnCode==3) { // max time - just choose one bestObjectIndex_ = list_[0]; bestWhichWay_ = 0; returnCode=0; } } else { bestObjectIndex_=list_[0]; } if ( bestObjectIndex_ >=0 ) { OsiObject * obj = solver->objects()[bestObjectIndex_]; obj->setWhichWay( bestWhichWay_); } if (numberFixed==numberUnsatisfied_&&numberFixed) returnCode=4; return returnCode; } else { return 1; } }