Ejemplo n.º 1
0
int main(int argc, char **argv) 
{
  char *f_name_lp, *last_dot_pos, f_name[256], *f_name_pos;
  int i, ncol;

  if((argc < 2) || (argc > 2)) {
    printf("### ERROR: main(): Usage: One of the following\ncgl_data_test input_file_name.mps\ncgl_data_test input_file_name.lp\n");
    exit(1);
  }

  f_name_lp = strdup(argv[1]);
  f_name_pos = strrchr(f_name_lp, '/');
  if(f_name_pos != NULL) {
    strcpy(f_name, &(f_name_pos[1]));
  }
  else {
    strcpy(f_name, f_name_lp);
  }
  last_dot_pos = strrchr(f_name, '.');
  if(last_dot_pos != NULL) {
    last_dot_pos = '\0';
  }

  OsiClpSolverInterface *clp = new OsiClpSolverInterface;
  clp->messageHandler()->setLogLevel(0);
  if(strcmp(&(f_name_lp[strlen(f_name_lp)-3]), ".lp") == 0) {
    clp->readLp(f_name_lp);    
  }
  else {
    if(strcmp(&(f_name_lp[strlen(f_name_lp)-4]), ".mps") == 0) {
      clp->readMps(f_name_lp);    
    }
    else {
      printf("### ERROR: unrecognized file type\n");
      exit(1);
    }
  }
  ncol = clp->getNumCols();
  clp->initialSolve();

  printf("LP value: %12.2f\n", clp->getObjValue());

  OsiCuts cuts;

  // Define parameters for CglRedSplit generator
  CglParam cpar;
  cpar.setMAX_SUPPORT(ncol+1);
  CglRedSplitParam rspar(cpar);

  // Create a cut generator with the given parameters
  CglRedSplit cutGen(rspar);

  char *colType = new char[ncol];
  for(i=0; i<ncol; i++) {
    if(clp->isContinuous(i)) {
      colType[i] = 'C';
    }
    else {
      colType[i] = 'I';
    }
  }

  int round, max_rounds = 10;
  for(round=0; round<max_rounds; round++) {
    cutGen.generateCuts(*clp, cuts);

    int ncuts = cuts.sizeRowCuts();

    const OsiRowCut **newRowCuts = new const OsiRowCut * [ncuts];
    for(i=0; i<ncuts; i++) {
      newRowCuts[i] = &cuts.rowCut(i); 
    }
    clp->applyRowCuts(ncuts, newRowCuts);
    delete[] newRowCuts;

    printf("round %4d: %4d generated cuts  new objective value: %12.2f\n", 
	   round, ncuts, clp->getObjValue());

    clp->resolve();  

    if(clp->isAbandoned()) {
      printf("###ERROR: Numerical difficulties in Solver\n");
      exit(1);
    }
  
    if(clp->isProvenPrimalInfeasible()) {
      printf("### WARNING: Problem is infeasible\n");
      exit(1);
    }
  }

  delete clp;
  free(f_name_lp);
  delete[] colType;

  return(0);
}
Ejemplo n.º 2
0
/*
  Randomized Rounding Heuristic
  Returns 1 if solution, 0 if not
*/
int
CbcHeuristicRandRound::solution(double & solutionValue,
                                double * betterSolution)
{
    // rlh: Todo: Memory Cleanup

    //  std::cout << "Entering the Randomized Rounding Heuristic" << std::endl;

    setWhen(1);  // setWhen(1) didn't have the effect I expected (e.g., run once).

    // Run only once.
    //
    //    See if at root node
    bool atRoot = model_->getNodeCount() == 0;
    int passNumber = model_->getCurrentPassNumber();
    //    Just do once
    if (!atRoot || passNumber > 1) {
        // std::cout << "Leaving the Randomized Rounding Heuristic" << std::endl;
        return 0;
    }

    std::cout << "Entering the Randomized Rounding Heuristic" << std::endl;
    typedef struct {
        int numberSolutions;
        int maximumSolutions;
        int numberColumns;
        double ** solution;
        int * numberUnsatisfied;
    } clpSolution;

    double start = CoinCpuTime();
    numCouldRun_++; //
#ifdef HEURISTIC_INFORM
    printf("Entering heuristic %s - nRuns %d numCould %d when %d\n",
	   heuristicName(),numRuns_,numCouldRun_,when_);
#endif
    // Todo: Ask JJHF what "number of times
    // the heuristic could run" means.

    OsiSolverInterface * solver = model_->solver()->clone();
    double primalTolerance ;
    solver->getDblParam(OsiPrimalTolerance, primalTolerance) ;
    OsiClpSolverInterface * clpSolver = dynamic_cast<OsiClpSolverInterface *> (solver);
    assert (clpSolver);
    ClpSimplex * simplex = clpSolver->getModelPtr();

    // Initialize the structure holding the solutions for the Simplex iterations
    clpSolution solutions;
    // Set typeStruct field of ClpTrustedData struct to 1 to indicate
    // desired behavior for  RandRound heuristic (which is what?)
    ClpTrustedData trustedSolutions;
    trustedSolutions.typeStruct = 1;
    trustedSolutions.data = &solutions;
    solutions.numberSolutions = 0;
    solutions.maximumSolutions = 0;
    solutions.numberColumns = simplex->numberColumns();
    solutions.solution = NULL;
    solutions.numberUnsatisfied = NULL;
    simplex->setTrustedUserPointer(&trustedSolutions);

    // Solve from all slack to get some points
    simplex->allSlackBasis();

    // Calling primal() invalidates pointers to some rim vectors,
    // like...row sense (!)
    simplex->primal();

    // 1. Okay - so a workaround would be to copy the data I want BEFORE
    // calling primal.
    // 2. Another approach is to ask the simplex solvers NOT to mess up my
    // rims.
    // 3. See freeCachedResults() for what is getting
    // deleted. Everything else points into the structure.
    // ...or use collower and colupper rather than rowsense.
    // ..store address of where one of these

    // Store the basic problem information
    // -Get the number of columns, rows and rhs vector
    int numCols = clpSolver->getNumCols();
    int numRows = clpSolver->getNumRows();

    // Find the integer variables (use columnType(?))
    // One if not continuous, that is binary or general integer)
    // columnType() = 0 continuous
    //              = 1 binary
    //              = 2 general integer
    bool * varClassInt = new bool[numCols];
    const char* columnType = clpSolver->columnType();
    int numGenInt = 0;
    for (int i = 0; i < numCols; i++) {
        if (clpSolver->isContinuous(i))
            varClassInt[i] = 0;
        else
            varClassInt[i] = 1;
        if (columnType[i] == 2) numGenInt++;
    }

    // Heuristic is for problems with general integer variables.
    // If there are none, quit.
    if (numGenInt++ < 1) {
        delete [] varClassInt ;
        std::cout << "Leaving the Randomized Rounding Heuristic" << std::endl;
        return 0;
    }


    // -Get the rows sense
    const char * rowSense;
    rowSense = clpSolver->getRowSense();

    // -Get the objective coefficients
    double *originalObjCoeff = CoinCopyOfArray(clpSolver->getObjCoefficients(), numCols);

    // -Get the matrix of the problem
    // rlh: look at using sparse representation
    double ** matrix = new double * [numRows];
    for (int i = 0; i < numRows; i++) {
        matrix[i] = new double[numCols];
        for (int j = 0; j < numCols; j++)
            matrix[i][j] = 0;
    }

    const CoinPackedMatrix* matrixByRow = clpSolver->getMatrixByRow();
    const double * matrixElements = matrixByRow->getElements();
    const int * matrixIndices = matrixByRow->getIndices();
    const int * matrixStarts = matrixByRow->getVectorStarts();
    for (int j = 0; j < numRows; j++) {
        for (int i = matrixStarts[j]; i < matrixStarts[j+1]; i++) {
            matrix[j][matrixIndices[i]] = matrixElements[i];
        }
    }

    double * newObj = new double [numCols];
    srand ( static_cast<unsigned int>(time(NULL) + 1));
    int randNum;

    // Shuffle the rows:
    // Put the rows in a random order
    // so that the optimal solution is a different corner point than the
    // starting point.
    int * index = new int [numRows];
    for (int i = 0; i < numRows; i++)
        index[i] = i;
    for (int i = 0; i < numRows; i++) {
        int temp = index[i];
        int randNumTemp = i + intRand(numRows - i);
        index[i] = index[randNumTemp];
        index[randNumTemp] = temp;
    }

    // Start finding corner points by iteratively doing the following:
    // - contruct a randomly tilted objective
    // - solve
    for (int i = 0; i < numRows; i++) {
        // TODO: that 10,000 could be a param in the member data
        if (solutions.numberSolutions  > 10000)
            break;
        randNum = intRand(2);
        for (int j = 0; j < numCols; j++) {
            // for row i and column j vary the coefficient "a bit"
            if (randNum == 1)
                // if the element is zero, then set the new obj
                // coefficient to 0.1 (i.e., round up)
                if (fabs(matrix[index[i]][j]) < primalTolerance)
                    newObj[j] = 0.1;
                else
                    // if the element is nonzero, then increase the new obj
                    // coefficient "a bit"
                    newObj[j] = matrix[index[i]][j] * 1.1;
            else
                // if randnum is 2, then
                // if the element is zero, then set the new obj coeffient
                // to NEGATIVE 0.1 (i.e., round down)
                if (fabs(matrix[index[i]][j]) < primalTolerance)
                    newObj[j] = -0.1;
                else
                    // if the element is nonzero, then DEcrease the new obj coeffienct "a bit"
                    newObj[j] = matrix[index[i]][j] * 0.9;
        }
        // Use the new "tilted" objective
        clpSolver->setObjective(newObj);

        // Based on the row sense, we decide whether to max or min
        if (rowSense[i] == 'L')
            clpSolver->setObjSense(-1);
        else
            clpSolver->setObjSense(1);

        // Solve with primal simplex
        simplex->primal(1);
        // rlh+ll: This was the original code. But we already have the
        // model pointer (it's in simplex). And, calling getModelPtr()
        // invalidates the cached data in the OsiClpSolverInterface
        // object, which means our precious rowsens is lost. So let's
        // not use the line below...
        /******* clpSolver->getModelPtr()->primal(1); */
        printf("---------------------------------------------------------------- %d\n", i);
    }
    // Iteratively do this process until...
    // either you reach the max number of corner points (aka 10K)
    // or all the rows have been used as an objective.

    // Look at solutions
    int numberSolutions = solutions.numberSolutions;
    //const char * integerInfo = simplex->integerInformation();
    //const double * columnLower = simplex->columnLower();
    //const double * columnUpper = simplex->columnUpper();
    printf("there are %d solutions\n", numberSolutions);

    // Up to here we have all the corner points
    // Now we need to do the random walks and roundings

    double ** cornerPoints = new double * [numberSolutions];
    for (int j = 0; j < numberSolutions; j++)
        cornerPoints[j] = solutions.solution[j];

    bool feasibility = 1;
    // rlh: use some COIN max instead of 1e30 (?)
    double bestObj = 1e30;
    std::vector< std::vector <double> > feasibles;
    int numFeasibles = 0;

    // Check the feasibility of the corner points
    int numCornerPoints = numberSolutions;

    const double * rhs = clpSolver->getRightHandSide();
    // rlh: row sense hasn't changed. why a fresh copy?
    // Delete next line.
    rowSense = clpSolver->getRowSense();

    for (int i = 0; i < numCornerPoints; i++) {
        //get the objective value for this this point
        double objValue = 0;
        for (int k = 0; k < numCols; k++)
            objValue += cornerPoints[i][k] * originalObjCoeff[k];

        if (objValue < bestObj) {
            // check integer feasibility
            feasibility = 1;
            for (int j = 0; j < numCols; j++) {
                if (varClassInt[j]) {
                    double closest = floor(cornerPoints[i][j] + 0.5);
                    if (fabs(cornerPoints[i][j] - closest) > primalTolerance) {
                        feasibility = 0;
                        break;
                    }
                }
            }
            // check all constraints satisfied
            if (feasibility) {
                for (int irow = 0; irow < numRows; irow++) {
                    double lhs = 0;
                    for (int j = 0; j < numCols; j++) {
                        lhs += matrix[irow][j] * cornerPoints[i][j];
                    }
                    if (rowSense[irow] == 'L' && lhs > rhs[irow] + primalTolerance) {
                        feasibility = 0;
                        break;
                    }
                    if (rowSense[irow] == 'G' && lhs < rhs[irow] - primalTolerance) {
                        feasibility = 0;
                        break;
                    }
                    if (rowSense[irow] == 'E' && (lhs - rhs[irow] > primalTolerance || lhs - rhs[irow] < -primalTolerance)) {
                        feasibility = 0;
                        break;
                    }
                }
            }

            if (feasibility) {
                numFeasibles++;
                feasibles.push_back(std::vector <double> (numCols));
                for (int k = 0; k < numCols; k++)
                    feasibles[numFeasibles-1][k] = cornerPoints[i][k];
                printf("obj: %f\n", objValue);
                if (objValue < bestObj)
                    bestObj = objValue;
            }
        }
    }
    int numFeasibleCorners;
    numFeasibleCorners = numFeasibles;
    //find the center of gravity of the corner points as the first random point
    double * rp = new double[numCols];
    for (int i = 0; i < numCols; i++) {
        rp[i] = 0;
        for (int j = 0; j < numCornerPoints; j++) {
            rp[i] += cornerPoints[j][i];
        }
        rp[i] = rp[i] / numCornerPoints;
    }

    //-------------------------------------------
    //main loop:
    // -generate the next random point
    // -round the random point
    // -check the feasibility of the random point
    //-------------------------------------------

    srand ( static_cast<unsigned int>(time(NULL) + 1));
    int numRandomPoints = 0;
    while (numRandomPoints < 50000) {
        numRandomPoints++;
        //generate the next random point
        int randomIndex = intRand(numCornerPoints);
        double random = CoinDrand48();
        for (int i = 0; i < numCols; i++) {
            rp[i] = (random * (cornerPoints[randomIndex][i] - rp[i])) + rp[i];
        }

        //CRISP ROUNDING
        //round the random point just generated
        double * roundRp = new double[numCols];
        for (int i = 0; i < numCols; i++) {
            roundRp[i] = rp[i];
            if (varClassInt[i]) {
                if (rp[i] >= 0) {
                    if (fmod(rp[i], 1) > 0.5)
                        roundRp[i] = floor(rp[i]) + 1;
                    else
                        roundRp[i] = floor(rp[i]);
                } else {
                    if (fabs(fmod(rp[i], 1)) > 0.5)
                        roundRp[i] = floor(rp[i]);
                    else
                        roundRp[i] = floor(rp[i]) + 1;

                }
            }
        }


        //SOFT ROUNDING
        // Look at original files for the "how to" on soft rounding;
        // Soft rounding omitted here.

        //Check the feasibility of the rounded random point
        // -Check the feasibility
        // -Get the rows sense
        rowSense = clpSolver->getRowSense();
        rhs = clpSolver->getRightHandSide();

        //get the objective value for this feasible point
        double objValue = 0;
        for (int i = 0; i < numCols; i++)
            objValue += roundRp[i] * originalObjCoeff[i];

        if (objValue < bestObj) {
            feasibility = 1;
            for (int i = 0; i < numRows; i++) {
                double lhs = 0;
                for (int j = 0; j < numCols; j++) {
                    lhs += matrix[i][j] * roundRp[j];
                }
                if (rowSense[i] == 'L' && lhs > rhs[i] + primalTolerance) {
                    feasibility = 0;
                    break;
                }
                if (rowSense[i] == 'G' && lhs < rhs[i] - primalTolerance) {
                    feasibility = 0;
                    break;
                }
                if (rowSense[i] == 'E' && (lhs - rhs[i] > primalTolerance || lhs - rhs[i] < -primalTolerance)) {
                    feasibility = 0;
                    break;
                }
            }
            if (feasibility) {
                printf("Feasible Found.\n");
                printf("%.2f\n", CoinCpuTime() - start);
                numFeasibles++;
                feasibles.push_back(std::vector <double> (numCols));
                for (int i = 0; i < numCols; i++)
                    feasibles[numFeasibles-1][i] = roundRp[i];
                printf("obj: %f\n", objValue);
                if (objValue < bestObj)
                    bestObj = objValue;
            }
        }
        delete [] roundRp;
    }
    printf("Number of Feasible Corners: %d\n", numFeasibleCorners);
    printf("Number of Feasibles Found: %d\n", numFeasibles);
    if (numFeasibles > 0)
        printf("Best Objective: %f\n", bestObj);
    printf("time: %.2f\n", CoinCpuTime() - start);

    if (numFeasibles == 0) {
        // cleanup
        delete [] varClassInt;
        for (int i = 0; i < numRows; i++)
            delete matrix[i];
        delete [] matrix;
        delete [] newObj;
        delete [] index;
        for (int i = 0; i < numberSolutions; i++)
            delete cornerPoints[i];
        delete [] cornerPoints;
        delete [] rp;
        return 0;
    }

    // We found something better
    solutionValue = bestObj;
    for (int k = 0; k < numCols; k++) {
        betterSolution[k] =  feasibles[numFeasibles-1][k];
    }
    delete [] varClassInt;
    for (int i = 0; i < numRows; i++)
        delete matrix[i];
    delete [] matrix;
    delete [] newObj;
    delete [] index;
    for (int i = 0; i < numberSolutions; i++)
        delete cornerPoints[i];
    delete [] cornerPoints;
    delete [] rp;
    std::cout << "Leaving the Randomized Rounding Heuristic" << std::endl;
    return 1;

}
Ejemplo n.º 3
0
int main (int argc, const char *argv[])
{

  // Define your favorite OsiSolver
  
  OsiClpSolverInterface solver1;

  // Read in model using argv[1]
  // and assert that it is a clean model
  std::string dirsep(1,CoinFindDirSeparator());
  std::string mpsFileName;
# if defined(SAMPLEDIR)
  mpsFileName = SAMPLEDIR ;
  mpsFileName += dirsep+"p0033.mps";
# else
  if (argc < 2) {
    fprintf(stderr, "Do not know where to find sample MPS files.\n");
    exit(1);
  }
# endif
  if (argc>=2) mpsFileName = argv[1];
  int numMpsReadErrors = solver1.readMps(mpsFileName.c_str(),"");
  if( numMpsReadErrors != 0 )
  {
     printf("%d errors reading MPS file\n", numMpsReadErrors);
     return numMpsReadErrors;
  }
  double time1 = CoinCpuTime();

  /* Options are:
     preprocess to do preprocessing
     time in minutes
     if 2 parameters and numeric taken as time
  */
  bool preProcess=false;
  double minutes=-1.0;
  int nGoodParam=0;
  for (int iParam=2; iParam<argc;iParam++) {
    if (!strcmp(argv[iParam],"preprocess")) {
      preProcess=true;
      nGoodParam++;
    } else if (!strcmp(argv[iParam],"time")) {
      if (iParam+1<argc&&isdigit(argv[iParam+1][0])) {
        minutes=atof(argv[iParam+1]);
        if (minutes>=0.0) {
          nGoodParam+=2;
          iParam++; // skip time
        }
      }
    }
  }
  if (nGoodParam==0&&argc==3&&isdigit(argv[2][0])) {
    // If time is given then stop after that number of minutes
    minutes = atof(argv[2]);
    if (minutes>=0.0) 
      nGoodParam=1;
  }
  if (nGoodParam!=argc-2&&argc>=2) {
    printf("Usage <file> [preprocess] [time <minutes>] or <file> <minutes>\n");
    exit(1);
  }
  solver1.initialSolve();
  // Reduce printout
  solver1.setHintParam(OsiDoReducePrint,true,OsiHintTry);
  // See if we want preprocessing
  OsiSolverInterface * solver2=&solver1;
#if PREPROCESS==1
  CglPreProcess process;
  if (preProcess) {
    /* Do not try and produce equality cliques and
       do up to 5 passes */
    solver2 = process.preProcess(solver1,false,5);
    if (!solver2) {
      printf("Pre-processing says infeasible\n");
      exit(2);
    }
    solver2->resolve();
  }
#endif
  CbcModel model(*solver2);
  model.solver()->setHintParam(OsiDoReducePrint,true,OsiHintTry);
  // Set up some cut generators and defaults
  // Probing first as gets tight bounds on continuous

  CglProbing generator1;
  generator1.setUsingObjective(true);
  generator1.setMaxPass(1);
  generator1.setMaxPassRoot(5);
  // Number of unsatisfied variables to look at
  generator1.setMaxProbe(10);
  generator1.setMaxProbeRoot(1000);
  // How far to follow the consequences
  generator1.setMaxLook(50);
  generator1.setMaxLookRoot(500);
  // Only look at rows with fewer than this number of elements
  generator1.setMaxElements(200);
  generator1.setRowCuts(3);

  CglGomory generator2;
  // try larger limit
  generator2.setLimit(300);

  CglKnapsackCover generator3;

  CglRedSplit generator4;
  // try larger limit
  generator4.setLimit(200);

  CglClique generator5;
  generator5.setStarCliqueReport(false);
  generator5.setRowCliqueReport(false);

  CglMixedIntegerRounding2 mixedGen;
  CglFlowCover flowGen;
  
  // Add in generators
  // Experiment with -1 and -99 etc
  model.addCutGenerator(&generator1,-1,"Probing");
  model.addCutGenerator(&generator2,-1,"Gomory");
  model.addCutGenerator(&generator3,-1,"Knapsack");
  // model.addCutGenerator(&generator4,-1,"RedSplit");
  model.addCutGenerator(&generator5,-1,"Clique");
  model.addCutGenerator(&flowGen,-1,"FlowCover");
  model.addCutGenerator(&mixedGen,-1,"MixedIntegerRounding");
  // Say we want timings
  int numberGenerators = model.numberCutGenerators();
  int iGenerator;
  for (iGenerator=0;iGenerator<numberGenerators;iGenerator++) {
    CbcCutGenerator * generator = model.cutGenerator(iGenerator);
    generator->setTiming(true);
  }
  OsiClpSolverInterface * osiclp = dynamic_cast< OsiClpSolverInterface*> (model.solver());
  // go faster stripes
  if (osiclp) {
    // Turn this off if you get problems
    // Used to be automatically set
    osiclp->setSpecialOptions(128);
    if(osiclp->getNumRows()<300&&osiclp->getNumCols()<500) {
      //osiclp->setupForRepeatedUse(2,0);
      osiclp->setupForRepeatedUse(0,0);
    }
  } 
  // Uncommenting this should switch off all CBC messages
  // model.messagesPointer()->setDetailMessages(10,10000,NULL);
  // Allow rounding heuristic

  CbcRounding heuristic1(model);
  model.addHeuristic(&heuristic1);

  // And local search when new solution found

  CbcHeuristicLocal heuristic2(model);
  model.addHeuristic(&heuristic2);

  // Redundant definition of default branching (as Default == User)
  CbcBranchUserDecision branch;
  model.setBranchingMethod(&branch);

  // Definition of node choice
  CbcCompareUser compare;
  model.setNodeComparison(compare);

  // Do initial solve to continuous
  model.initialSolve();

  // Could tune more
  double objValue = model.solver()->getObjSense()*model.solver()->getObjValue();
  double minimumDropA=CoinMin(1.0,fabs(objValue)*1.0e-3+1.0e-4);
  double minimumDrop= fabs(objValue)*1.0e-4+1.0e-4;
  printf("min drop %g (A %g)\n",minimumDrop,minimumDropA);
  model.setMinimumDrop(minimumDrop);

  if (model.getNumCols()<500)
    model.setMaximumCutPassesAtRoot(-100); // always do 100 if possible
  else if (model.getNumCols()<5000)
    model.setMaximumCutPassesAtRoot(100); // use minimum drop
  else
    model.setMaximumCutPassesAtRoot(20);
  model.setMaximumCutPasses(10);
  //model.setMaximumCutPasses(2);

  // Switch off strong branching if wanted
  // model.setNumberStrong(0);
  // Do more strong branching if small
  if (model.getNumCols()<5000)
    model.setNumberStrong(10);
  model.setNumberStrong(20);
  //model.setNumberStrong(5);
  model.setNumberBeforeTrust(5);

  model.solver()->setIntParam(OsiMaxNumIterationHotStart,100);

  // If time is given then stop after that number of minutes
  if (minutes>=0.0) {
    std::cout<<"Stopping after "<<minutes<<" minutes"<<std::endl;
    model.setDblParam(CbcModel::CbcMaximumSeconds,60.0*minutes);
  }
  // Switch off most output
  if (model.getNumCols()<3000) {
    model.messageHandler()->setLogLevel(1);
    //model.solver()->messageHandler()->setLogLevel(0);
  } else {
    model.messageHandler()->setLogLevel(2);
    model.solver()->messageHandler()->setLogLevel(1);
  }
  //model.messageHandler()->setLogLevel(2);
  //model.solver()->messageHandler()->setLogLevel(2);
  //model.setPrintFrequency(50);
  //#define DEBUG_CUTS
#ifdef DEBUG_CUTS
  // Set up debugger by name (only if no preprocesing)
  if (!preProcess) {
    std::string problemName ;
    model.solver()->getStrParam(OsiProbName,problemName) ;
    model.solver()->activateRowCutDebugger(problemName.c_str()) ;
  }
#endif
#if PREPROCESS==2
  // Default strategy will leave cut generators as they exist already
  // so cutsOnlyAtRoot (1) ignored
  // numberStrong (2) is 5 (default)
  // numberBeforeTrust (3) is 5 (default is 0)
  // printLevel (4) defaults (0)
  CbcStrategyDefault strategy(true,5,5);
  // Set up pre-processing to find sos if wanted
  if (preProcess)
    strategy.setupPreProcessing(2);
  model.setStrategy(strategy);
#endif
  // Do complete search
  
  model.branchAndBound();

  std::cout<<mpsFileName<<" took "<<CoinCpuTime()-time1<<" seconds, "
	   <<model.getNodeCount()<<" nodes with objective "
	   <<model.getObjValue()
	   <<(!model.status() ? " Finished" : " Not finished")
	   <<std::endl;

  // Print more statistics
  std::cout<<"Cuts at root node changed objective from "<<model.getContinuousObjective()
	   <<" to "<<model.rootObjectiveAfterCuts()<<std::endl;

  for (iGenerator=0;iGenerator<numberGenerators;iGenerator++) {
    CbcCutGenerator * generator = model.cutGenerator(iGenerator);
    std::cout<<generator->cutGeneratorName()<<" was tried "
	     <<generator->numberTimesEntered()<<" times and created "
	     <<generator->numberCutsInTotal()<<" cuts of which "
	     <<generator->numberCutsActive()<<" were active after adding rounds of cuts";
    if (generator->timing())
      std::cout<<" ( "<<generator->timeInCutGenerator()<<" seconds)"<<std::endl;
    else
      std::cout<<std::endl;
  }
  // Print solution if finished - we can't get names from Osi! - so get from OsiClp

  if (model.getMinimizationObjValue()<1.0e50) {
#if PREPROCESS==1
    // post process
    OsiSolverInterface * solver;
    if (preProcess) {
      process.postProcess(*model.solver());
      // Solution now back in solver1
      solver = & solver1;
    } else {
      solver = model.solver();
    }
#else
    OsiSolverInterface * solver = model.solver();
#endif
    int numberColumns = solver->getNumCols();
    
    const double * solution = solver->getColSolution();

    // Get names from solver1 (as OsiSolverInterface may lose)
    std::vector<std::string> columnNames = *solver1.getModelPtr()->columnNames();
    
    int iColumn;
    std::cout<<std::setiosflags(std::ios::fixed|std::ios::showpoint)<<std::setw(14);
    
    std::cout<<"--------------------------------------"<<std::endl;
    for (iColumn=0;iColumn<numberColumns;iColumn++) {
      double value=solution[iColumn];
      if (fabs(value)>1.0e-7&&solver->isInteger(iColumn)) 
	std::cout<<std::setw(6)<<iColumn<<" "
                 <<columnNames[iColumn]<<" "
                 <<value<<std::endl;
    }
    std::cout<<"--------------------------------------"<<std::endl;
  
    std::cout<<std::resetiosflags(std::ios::fixed|std::ios::showpoint|std::ios::scientific);
  }
  return 0;
}    
Ejemplo n.º 4
0
int main (int argc, const char *argv[])
{

  /* Define your favorite OsiSolver.

     CbcModel clones the solver so use solver1 up to the time you pass it
     to CbcModel then use a pointer to cloned solver (model.solver())
  */
  
  OsiClpSolverInterface solver1;
  /* From now on we can build model in a solver independent way.
     You can add rows one at a time but for large problems this is slow so
     this example uses CoinBuild or CoinModel
  */
  OsiSolverInterface * solver = &solver1;
  // Data (is exmip1.mps in Mps/Sample
  // Objective 
  double objValue[]={1.0,2.0,0.0,0.0,0.0,0.0,0.0,-1.0};
  // Lower bounds for columns
  double columnLower[]={2.5,0.0,0.0,0.0,0.5,0.0,0.0,0.0};
  // Upper bounds for columns
  double columnUpper[]={COIN_DBL_MAX,4.1,1.0,1.0,4.0,
                  COIN_DBL_MAX,COIN_DBL_MAX,4.3};
  // Lower bounds for row activities
  double rowLower[]={2.5,-COIN_DBL_MAX,-COIN_DBL_MAX,1.8,3.0};
  // Upper bounds for row activities
  double rowUpper[]={COIN_DBL_MAX,2.1,4.0,5.0,15.0};
  // Matrix stored packed
  int column[] = {0,1,3,4,7,
                  1,2,
                  2,5,
                  3,6,
                  4,7};
  double element[] = {3.0,1.0,-2.0,-1.0,-1.0,
                      2.0,1.1,
                      1.0,1.0,
                      2.8,-1.2,
                      1.0,1.9};
  int starts[]={0,5,7,9,11,13};
  // Integer variables (note upper bound already 1.0)
  int whichInt[]={2,3};
  int numberRows=(int) (sizeof(rowLower)/sizeof(double));
  int numberColumns=(int) (sizeof(columnLower)/sizeof(double));
#define BUILD 2
#if BUILD==1
  // Using CoinBuild 
  // First do columns (objective and bounds)
  int i;
  // We are not adding elements 
  for (i=0;i<numberColumns;i++) {
    solver->addCol(0,NULL,NULL,columnLower[i],columnUpper[i],
                    objValue[i]);
  }
  // mark as integer
  for (i=0;i<(int) (sizeof(whichInt)/sizeof(int));i++)
    solver->setInteger(whichInt[i]);
  // Now build rows
  CoinBuild build;
  for (i=0;i<numberRows;i++) {
    int startRow = starts[i];
    int numberInRow = starts[i+1]-starts[i];
    build.addRow(numberInRow,column+startRow,element+startRow,
                 rowLower[i],rowUpper[i]);
  }  
  // add rows into solver
  solver->addRows(build);
#else
  /* using CoinModel - more flexible but still beta.
     Can do exactly same way but can mix and match much more.
     Also all operations are on building object
  */
  CoinModel build;
  // First do columns (objective and bounds)
  int i;
  for (i=0;i<numberColumns;i++) {
    build.setColumnBounds(i,columnLower[i],columnUpper[i]);
    build.setObjective(i,objValue[i]);
  }
  // mark as integer
  for (i=0;i<(int) (sizeof(whichInt)/sizeof(int));i++)
    build.setInteger(whichInt[i]);
  // Now build rows
  for (i=0;i<numberRows;i++) {
    int startRow = starts[i];
    int numberInRow = starts[i+1]-starts[i];
    build.addRow(numberInRow,column+startRow,element+startRow,
                 rowLower[i],rowUpper[i]);
  }  
  // add rows into solver
  solver->loadFromCoinModel(build);
#endif

  // Pass to solver
  CbcModel model(*solver);
  model.solver()->setHintParam(OsiDoReducePrint,true,OsiHintTry);


  // Set up some cut generators and defaults
  // Probing first as gets tight bounds on continuous

  CglProbing generator1;
  generator1.setUsingObjective(true);
  generator1.setMaxPass(3);
  generator1.setMaxProbe(100);
  generator1.setMaxLook(50);
  generator1.setRowCuts(3);
  //  generator1.snapshot(*model.solver());
  //generator1.createCliques(*model.solver(),2,1000,true);
  //generator1.setMode(0);

  CglGomory generator2;
  // try larger limit
  generator2.setLimit(300);

  CglKnapsackCover generator3;

  CglOddHole generator4;
  generator4.setMinimumViolation(0.005);
  generator4.setMinimumViolationPer(0.00002);
  // try larger limit
  generator4.setMaximumEntries(200);

  CglClique generator5;
  generator5.setStarCliqueReport(false);
  generator5.setRowCliqueReport(false);

  CglMixedIntegerRounding mixedGen;
  CglFlowCover flowGen;
  
  // Add in generators
  model.addCutGenerator(&generator1,-1,"Probing");
  model.addCutGenerator(&generator2,-1,"Gomory");
  model.addCutGenerator(&generator3,-1,"Knapsack");
  model.addCutGenerator(&generator4,-1,"OddHole");
  model.addCutGenerator(&generator5,-1,"Clique");
  model.addCutGenerator(&flowGen,-1,"FlowCover");
  model.addCutGenerator(&mixedGen,-1,"MixedIntegerRounding");

  OsiClpSolverInterface * osiclp = dynamic_cast< OsiClpSolverInterface*> (model.solver());
  // go faster stripes
  if (osiclp->getNumRows()<300&&osiclp->getNumCols()<500) {
    osiclp->setupForRepeatedUse(2,0);
    printf("trying slightly less reliable but faster version (? Gomory cuts okay?)\n");
    printf("may not be safe if doing cuts in tree which need accuracy (level 2 anyway)\n");
  }

  // Allow rounding heuristic

  CbcRounding heuristic1(model);
  model.addHeuristic(&heuristic1);

  // And local search when new solution found

  CbcHeuristicLocal heuristic2(model);
  model.addHeuristic(&heuristic2);

  // Redundant definition of default branching (as Default == User)
  CbcBranchUserDecision branch;
  model.setBranchingMethod(&branch);

  // Definition of node choice
  CbcCompareUser compare;
  model.setNodeComparison(compare);

  // Do initial solve to continuous
  model.initialSolve();

  // Could tune more
  model.setMinimumDrop(CoinMin(1.0,
			     fabs(model.getMinimizationObjValue())*1.0e-3+1.0e-4));

  if (model.getNumCols()<500)
    model.setMaximumCutPassesAtRoot(-100); // always do 100 if possible
  else if (model.getNumCols()<5000)
    model.setMaximumCutPassesAtRoot(100); // use minimum drop
  else
    model.setMaximumCutPassesAtRoot(20);
  //model.setMaximumCutPasses(5);

  // Switch off strong branching if wanted
  // model.setNumberStrong(0);
  // Do more strong branching if small
  if (model.getNumCols()<5000)
    model.setNumberStrong(10);

  model.solver()->setIntParam(OsiMaxNumIterationHotStart,100);

  // If time is given then stop after that number of minutes
  if (argc>2) {
    int minutes = atoi(argv[2]);
    std::cout<<"Stopping after "<<minutes<<" minutes"<<std::endl;
    assert (minutes>=0);
    model.setDblParam(CbcModel::CbcMaximumSeconds,60.0*minutes);
  }
  // Switch off most output
  if (model.getNumCols()<3000) {
    model.messageHandler()->setLogLevel(1);
    //model.solver()->messageHandler()->setLogLevel(0);
  } else {
    model.messageHandler()->setLogLevel(2);
    model.solver()->messageHandler()->setLogLevel(1);
  }
  double time1 = CoinCpuTime();

  // Do complete search
  
  model.branchAndBound();

  std::cout<<" Branch and cut took "<<CoinCpuTime()-time1<<" seconds, "
	   <<model.getNodeCount()<<" nodes with objective "
	   <<model.getObjValue()
	   <<(!model.status() ? " Finished" : " Not finished")
	   <<std::endl;

  // Print more statistics
  std::cout<<"Cuts at root node changed objective from "<<model.getContinuousObjective()
	   <<" to "<<model.rootObjectiveAfterCuts()<<std::endl;

  int numberGenerators = model.numberCutGenerators();
  for (int iGenerator=0;iGenerator<numberGenerators;iGenerator++) {
    CbcCutGenerator * generator = model.cutGenerator(iGenerator);
    std::cout<<generator->cutGeneratorName()<<" was tried "
	     <<generator->numberTimesEntered()<<" times and created "
	     <<generator->numberCutsInTotal()<<" cuts of which "
	     <<generator->numberCutsActive()<<" were active after adding rounds of cuts"
	     <<std::endl;
  }
  // Print solution if any - we can't get names from Osi!

  if (model.getMinimizationObjValue()<1.0e50) {
    int numberColumns = model.solver()->getNumCols();
    
    const double * solution = model.solver()->getColSolution();
    
    int iColumn;
    std::cout<<std::setiosflags(std::ios::fixed|std::ios::showpoint)<<std::setw(14);
    
    std::cout<<"--------------------------------------"<<std::endl;
    for (iColumn=0;iColumn<numberColumns;iColumn++) {
      double value=solution[iColumn];
      if (fabs(value)>1.0e-7&&model.solver()->isInteger(iColumn)) 
	std::cout<<std::setw(6)<<iColumn<<" "<<value<<std::endl;
    }
    std::cout<<"--------------------------------------"<<std::endl;
  
    std::cout<<std::resetiosflags(std::ios::fixed|std::ios::showpoint|std::ios::scientific);
  }
  return 0;
}    
Ejemplo n.º 5
0
int main (int argc, const char *argv[])
{

  // Define your favorite OsiSolver
  
  OsiClpSolverInterface solver1;

  // Read in model using argv[1]
  // and assert that it is a clean model
  std::string mpsFileName;
#if defined(SAMPLEDIR)
  mpsFileName = SAMPLEDIR "/p0033.mps";
#else
  if (argc < 2) {
    fprintf(stderr, "Do not know where to find sample MPS files.\n");
    exit(1);
  }
#endif
  if (argc>=2) mpsFileName = argv[1];
  int numMpsReadErrors = solver1.readMps(mpsFileName.c_str(),"");
  assert(numMpsReadErrors==0);
  double time1 = CoinCpuTime();

  /* Options are:
     preprocess to do preprocessing
     time in minutes
     if 2 parameters and numeric taken as time
  */
  bool preProcess=false;
  double minutes=-1.0;
  int nGoodParam=0;
  for (int iParam=2; iParam<argc;iParam++) {
    if (!strcmp(argv[iParam],"preprocess")) {
      preProcess=true;
      nGoodParam++;
    } else if (!strcmp(argv[iParam],"time")) {
      if (iParam+1<argc&&isdigit(argv[iParam+1][0])) {
        minutes=atof(argv[iParam+1]);
        if (minutes>=0.0) {
          nGoodParam+=2;
          iParam++; // skip time
        }
      }
    }
  }
  if (nGoodParam==0&&argc==3&&isdigit(argv[2][0])) {
    // If time is given then stop after that number of minutes
    minutes = atof(argv[2]);
    if (minutes>=0.0) 
      nGoodParam=1;
  }
  if (nGoodParam!=argc-2&&argc>=2) {
    printf("Usage <file> [preprocess] [time <minutes>] or <file> <minutes>\n");
    exit(1);
  }
  //solver1.getModelPtr()->setLogLevel(0);
  solver1.messageHandler()->setLogLevel(0);
  solver1.initialSolve();
  // Reduce printout
  solver1.setHintParam(OsiDoReducePrint,true,OsiHintTry);
  CbcModel model(solver1);
  model.solver()->setHintParam(OsiDoReducePrint,true,OsiHintTry);
  // Set up some cut generators and defaults
  // Probing first as gets tight bounds on continuous

  CglProbing generator1;
  generator1.setUsingObjective(true);
  generator1.setMaxPass(1);
  generator1.setMaxPassRoot(5);
  // Number of unsatisfied variables to look at
  generator1.setMaxProbe(10);
  generator1.setMaxProbeRoot(1000);
  // How far to follow the consequences
  generator1.setMaxLook(50);
  generator1.setMaxLookRoot(500);
  // Only look at rows with fewer than this number of elements
  generator1.setMaxElements(200);
  generator1.setRowCuts(3);

  CglGomory generator2;
  // try larger limit
  generator2.setLimit(300);

  CglKnapsackCover generator3;

  CglRedSplit generator4;
  // try larger limit
  generator4.setLimit(200);

  CglClique generator5;
  generator5.setStarCliqueReport(false);
  generator5.setRowCliqueReport(false);

  CglMixedIntegerRounding2 mixedGen;
  CglFlowCover flowGen;
  
  // Add in generators
  // Experiment with -1 and -99 etc
  model.addCutGenerator(&generator1,-1,"Probing");
  model.addCutGenerator(&generator2,-1,"Gomory");
  model.addCutGenerator(&generator3,-1,"Knapsack");
  // model.addCutGenerator(&generator4,-1,"RedSplit");
  model.addCutGenerator(&generator5,-1,"Clique");
  model.addCutGenerator(&flowGen,-1,"FlowCover");
  model.addCutGenerator(&mixedGen,-1,"MixedIntegerRounding");
  OsiClpSolverInterface * osiclp = dynamic_cast< OsiClpSolverInterface*> (model.solver());
  // go faster stripes
  if (osiclp) {
    // Turn this off if you get problems
    // Used to be automatically set
    osiclp->setSpecialOptions(128);
    if(osiclp->getNumRows()<300&&osiclp->getNumCols()<500) {
      //osiclp->setupForRepeatedUse(2,1);
      osiclp->setupForRepeatedUse(0,1);
    }
  } 
  // Uncommenting this should switch off most CBC messages
  //model.messagesPointer()->setDetailMessages(10,5,5000);
  // Allow rounding heuristic

  CbcRounding heuristic1(model);
  model.addHeuristic(&heuristic1);

  // And local search when new solution found

  CbcHeuristicLocal heuristic2(model);
  model.addHeuristic(&heuristic2);

  // Redundant definition of default branching (as Default == User)
  CbcBranchUserDecision branch;
  model.setBranchingMethod(&branch);

  // Definition of node choice
  CbcCompareUser compare;
  model.setNodeComparison(compare);

  // Do initial solve to continuous
  model.initialSolve();

  // Could tune more
  double objValue = model.solver()->getObjSense()*model.solver()->getObjValue();
  double minimumDropA=CoinMin(1.0,fabs(objValue)*1.0e-3+1.0e-4);
  double minimumDrop= fabs(objValue)*1.0e-4+1.0e-4;
  printf("min drop %g (A %g)\n",minimumDrop,minimumDropA);
  model.setMinimumDrop(minimumDrop);

  if (model.getNumCols()<500)
    model.setMaximumCutPassesAtRoot(-100); // always do 100 if possible
  else if (model.getNumCols()<5000)
    model.setMaximumCutPassesAtRoot(100); // use minimum drop
  else
    model.setMaximumCutPassesAtRoot(20);
  model.setMaximumCutPasses(10);
  //model.setMaximumCutPasses(2);

  // Switch off strong branching if wanted
  // model.setNumberStrong(0);
  // Do more strong branching if small
  if (model.getNumCols()<5000)
    model.setNumberStrong(10);
  model.setNumberStrong(20);
  //model.setNumberStrong(5);
  model.setNumberBeforeTrust(5);
  //model.setSizeMiniTree(2);

  model.solver()->setIntParam(OsiMaxNumIterationHotStart,100);

  // If time is given then stop after that number of minutes
  if (minutes>=0.0) {
    std::cout<<"Stopping after "<<minutes<<" minutes"<<std::endl;
    model.setDblParam(CbcModel::CbcMaximumSeconds,60.0*minutes);
  }
  // Switch off most output
  if (model.getNumCols()<3000) {
    model.messageHandler()->setLogLevel(1);
    //model.solver()->messageHandler()->setLogLevel(0);
  } else {
    model.messageHandler()->setLogLevel(2);
    model.solver()->messageHandler()->setLogLevel(1);
  }
  // Default strategy will leave cut generators as they exist already
  // so cutsOnlyAtRoot (1) ignored
  // numberStrong (2) is 5 (default)
  // numberBeforeTrust (3) is 5 (default is 0)
  // printLevel (4) defaults (0)
  CbcStrategyDefault strategy(true,5,5);
  // Set up pre-processing to find sos if wanted
  if (preProcess)
    strategy.setupPreProcessing(2);
  model.setStrategy(strategy);

  // Go round adding cuts to cutoff last solution
  // Stop after finding 20 best solutions
  for (int iPass=0;iPass<20;iPass++) {
    time1 = CoinCpuTime();
    // Do complete search
    model.branchAndBound();
    
    std::cout<<mpsFileName<<" took "<<CoinCpuTime()-time1<<" seconds, "
             <<model.getNodeCount()<<" nodes with objective "
             <<model.getObjValue()
             <<(!model.status() ? " Finished" : " Not finished")
             <<std::endl;
    // Stop if infeasible
    if (model.isProvenInfeasible())
      break;
    // Print solution if finished - we can't get names from Osi! - so get from OsiClp
    
    assert (model.getMinimizationObjValue()<1.0e50);
    OsiSolverInterface * solver = model.solver();
    int numberColumns = solver->getNumCols();
    
    const double * solution = model.bestSolution();
    //const double * lower = solver->getColLower();
    //const double * upper = solver->getColUpper();

    // Get names from solver1 (as OsiSolverInterface may lose)
    std::vector<std::string> columnNames = *solver1.getModelPtr()->columnNames();
    
    int iColumn;
    std::cout<<std::setiosflags(std::ios::fixed|std::ios::showpoint)<<std::setw(14);
    
    std::cout<<"--------------------------------------"<<std::endl;
    for (iColumn=0;iColumn<numberColumns;iColumn++) {
      double value=solution[iColumn];
      if (fabs(value)>1.0e-7&&solver->isInteger(iColumn)) 
	std::cout<<std::setw(6)<<iColumn<<" "
                 <<columnNames[iColumn]<<" "
                 <<value
          //<<" "<<lower[iColumn]<<" "<<upper[iColumn]
                 <<std::endl;
    }
    std::cout<<"--------------------------------------"<<std::endl;
  
    std::cout<<std::resetiosflags(std::ios::fixed|std::ios::showpoint|std::ios::scientific);
    /* Now add cut to reference copy.
       resetting to reference copy also gets rid of best solution so we
       should either save best solution, reset, add cut OR
       add cut to reference copy then reset - this is doing latter
    */
    OsiSolverInterface * refSolver = model.referenceSolver();
    const double * bestSolution = model.bestSolution();
    const double * originalLower = refSolver->getColLower();
    const double * originalUpper = refSolver->getColUpper();
    CoinPackedVector cut;
    double rhs = 1.0;
    for (iColumn=0;iColumn<numberColumns;iColumn++) {
      double value=bestSolution[iColumn];
      if (solver->isInteger(iColumn)) {
        // only works for 0-1 variables
        assert (originalLower[iColumn]==0.0&&
                originalUpper[iColumn]==1.0);
        // double check integer
        assert (fabs(floor(value+0.5)-value)<1.0e-5);
        if (value>0.5) {
          // at 1.0
          cut.insert(iColumn,-1.0);
          rhs -= 1.0;
        } else {
          // at 0.0
          cut.insert(iColumn,1.0);
        }
      }
    }
    // now add cut
    refSolver->addRow(cut,rhs,COIN_DBL_MAX);
    model.resetToReferenceSolver();
  }
  return 0;
}    
Ejemplo n.º 6
0
int main (int argc, const char *argv[])
{

  // Define your favorite OsiSolver
  
  OsiClpSolverInterface solver1;

  // Read in model using argv[1]
  // and assert that it is a clean model
  std::string mpsFileName;
#if defined(SAMPLEDIR)
  mpsFileName = SAMPLEDIR "/p0033.mps";
#else
  if (argc < 2) {
    fprintf(stderr, "Do not know where to find sample MPS files.\n");
    exit(1);
  }
#endif
  if (argc>=2) mpsFileName = argv[1];
  int numMpsReadErrors = solver1.readMps(mpsFileName.c_str(),"");
  assert(numMpsReadErrors==0);
  double time1 = CoinCpuTime();
  OsiClpSolverInterface solverSave = solver1;

  /* Options are:
     preprocess to do preprocessing
     time in minutes
     if 2 parameters and numeric taken as time
  */
  bool preProcess=false;
  double minutes=-1.0;
  int nGoodParam=0;
  for (int iParam=2; iParam<argc;iParam++) {
    if (!strcmp(argv[iParam],"preprocess")) {
      preProcess=true;
      nGoodParam++;
    } else if (!strcmp(argv[iParam],"time")) {
      if (iParam+1<argc&&isdigit(argv[iParam+1][0])) {
        minutes=atof(argv[iParam+1]);
        if (minutes>=0.0) {
          nGoodParam+=2;
          iParam++; // skip time
        }
      }
    }
  }
  if (nGoodParam==0&&argc==3&&isdigit(argv[2][0])) {
    // If time is given then stop after that number of minutes
    minutes = atof(argv[2]);
    if (minutes>=0.0) 
      nGoodParam=1;
  }
  if (nGoodParam!=argc-2&&argc>=2) {
    printf("Usage <file> [preprocess] [time <minutes>] or <file> <minutes>\n");
    exit(1);
  }
  // Reduce printout
  solver1.setHintParam(OsiDoReducePrint,true,OsiHintTry);
  // See if we want preprocessing
  OsiSolverInterface * solver2=&solver1;
  CglPreProcess process;
  // Never do preprocessing until dual tests out as can fix incorrectly
  preProcess=false;
  if (preProcess) {
    /* Do not try and produce equality cliques and
       do up to 5 passes */
    solver2 = process.preProcess(solver1,false,5);
    if (!solver2) {
      printf("Pre-processing says infeasible\n");
      exit(2);
    }
    solver2->resolve();
  }
  // Turn L rows into cuts
  CglStoredUser stored;
 {
  int numberRows = solver2->getNumRows();

  int * whichRow = new int[numberRows];
  // get row copy
  const CoinPackedMatrix * rowCopy = solver2->getMatrixByRow();
  const int * column = rowCopy->getIndices();
  const int * rowLength = rowCopy->getVectorLengths();
  const CoinBigIndex * rowStart = rowCopy->getVectorStarts();
  const double * rowLower = solver2->getRowLower();
  const double * rowUpper = solver2->getRowUpper();
  const double * element = rowCopy->getElements();
  int iRow,nDelete=0;
  for (iRow=0;iRow<numberRows;iRow++) {
    if (rowLower[iRow]<-1.0e20||rowUpper[iRow]>1.0e20) {
      // take out
      whichRow[nDelete++]=iRow;
    }
  }
  // leave some rows to avoid empty problem (Gomory does not like)
  nDelete = CoinMax(CoinMin(nDelete,numberRows-5),0);
  for (int jRow=0;jRow<nDelete;jRow++) {
    iRow=whichRow[jRow];
    int start = rowStart[iRow];
    stored.addCut(rowLower[iRow],rowUpper[iRow],rowLength[iRow],
		  column+start,element+start);
  }
  /* The following is problem specific.
     Normally cuts are deleted if slack on cut basic.
     On some problems you may wish to leave cuts in as long
     as slack value zero
  */
  int numberCuts=stored.sizeRowCuts();
  for (int iCut=0;iCut<numberCuts;iCut++) {
    //stored.mutableRowCutPointer(iCut)->setEffectiveness(1.0e50);
  }
  solver2->deleteRows(nDelete,whichRow);
  delete [] whichRow;
 }
  CbcModel model(*solver2);
  model.solver()->setHintParam(OsiDoReducePrint,true,OsiHintTry);
  // Set up some cut generators and defaults
  // Probing first as gets tight bounds on continuous

  CglProbing generator1;
  generator1.setUsingObjective(true);
  generator1.setMaxPass(1);
  generator1.setMaxPassRoot(5);
  // Number of unsatisfied variables to look at
  generator1.setMaxProbe(10);
  generator1.setMaxProbeRoot(1000);
  // How far to follow the consequences
  generator1.setMaxLook(50);
  generator1.setMaxLookRoot(500);
  // Only look at rows with fewer than this number of elements
  generator1.setMaxElements(200);
  generator1.setRowCuts(3);

  CglGomory generator2;
  // try larger limit
  generator2.setLimit(300);

  CglKnapsackCover generator3;

  CglRedSplit generator4;
  // try larger limit
  generator4.setLimit(200);

  CglClique generator5;
  generator5.setStarCliqueReport(false);
  generator5.setRowCliqueReport(false);

  CglMixedIntegerRounding2 mixedGen;
  CglFlowCover flowGen;
  
  // Add in generators
  // Experiment with -1 and -99 etc
  // This is just for one particular model
  model.addCutGenerator(&generator1,-1,"Probing");
  //model.addCutGenerator(&generator2,-1,"Gomory");
  model.addCutGenerator(&generator2,1,"Gomory");
  model.addCutGenerator(&generator3,-1,"Knapsack");
  // model.addCutGenerator(&generator4,-1,"RedSplit");
  //model.addCutGenerator(&generator5,-1,"Clique");
  model.addCutGenerator(&generator5,1,"Clique");
  model.addCutGenerator(&flowGen,-1,"FlowCover");
  model.addCutGenerator(&mixedGen,-1,"MixedIntegerRounding");
  // Add stored cuts (making sure at all depths)
  model.addCutGenerator(&stored,1,"Stored",true,false,false,-100,1,-1);
  
  int numberGenerators = model.numberCutGenerators();
  int iGenerator;
  // Say we want timings
  for (iGenerator=0;iGenerator<numberGenerators;iGenerator++) {
    CbcCutGenerator * generator = model.cutGenerator(iGenerator);
    generator->setTiming(true);
  }
  OsiClpSolverInterface * osiclp = dynamic_cast< OsiClpSolverInterface*> (model.solver());
  // go faster stripes
  if (osiclp) { 
    if(osiclp->getNumRows()<300&&osiclp->getNumCols()<500) {
      //osiclp->setupForRepeatedUse(2,0);
      osiclp->setupForRepeatedUse(0,0);
    }
    // Don't allow dual stuff
    osiclp->setSpecialOptions(osiclp->specialOptions()|262144);
  } 
  // Uncommenting this should switch off all CBC messages
  // model.messagesPointer()->setDetailMessages(10,10000,NULL);
  // No heuristics
  // Do initial solve to continuous
  model.initialSolve();
  /*  You need the next few lines -
      a) so that cut generator will always be called again if it generated cuts
      b) it is known that matrix is not enough to define problem so do cuts even
         if it looks integer feasible at continuous optimum.
      c) a solution found by strong branching will be ignored.
      d) don't recompute a solution once found
  */
  // Make sure cut generator called correctly (a)
  iGenerator=numberGenerators-1;
  model.cutGenerator(iGenerator)->setMustCallAgain(true);
  // Say cuts needed at continuous (b)
  OsiBabSolver oddCuts;
  oddCuts.setSolverType(4);
  // owing to bug must set after initialSolve
  model.passInSolverCharacteristics(&oddCuts);
  // Say no to all solutions by strong branching (c)
  CbcFeasibilityNoStrong noStrong;
  model.setProblemFeasibility(noStrong);
  // Say don't recompute solution d)
  model.setSpecialOptions(4);

  // Could tune more
  double objValue = model.solver()->getObjSense()*model.solver()->getObjValue();
  double minimumDropA=CoinMin(1.0,fabs(objValue)*1.0e-3+1.0e-4);
  double minimumDrop= fabs(objValue)*1.0e-4+1.0e-4;
  printf("min drop %g (A %g)\n",minimumDrop,minimumDropA);
  model.setMinimumDrop(minimumDrop);

  if (model.getNumCols()<500)
    model.setMaximumCutPassesAtRoot(-100); // always do 100 if possible
  else if (model.getNumCols()<5000)
    model.setMaximumCutPassesAtRoot(100); // use minimum drop
  else
    model.setMaximumCutPassesAtRoot(20);
  model.setMaximumCutPasses(10);
  //model.setMaximumCutPasses(2);

  // Switch off strong branching if wanted
  // model.setNumberStrong(0);
  // Do more strong branching if small
  if (model.getNumCols()<5000)
    model.setNumberStrong(10);
  model.setNumberStrong(20);
  //model.setNumberStrong(5);
  model.setNumberBeforeTrust(5);

  model.solver()->setIntParam(OsiMaxNumIterationHotStart,100);

  // If time is given then stop after that number of minutes
  if (minutes>=0.0) {
    std::cout<<"Stopping after "<<minutes<<" minutes"<<std::endl;
    model.setDblParam(CbcModel::CbcMaximumSeconds,60.0*minutes);
  }
  // Switch off most output
  if (model.getNumCols()<30000) {
    model.messageHandler()->setLogLevel(1);
    //model.solver()->messageHandler()->setLogLevel(0);
  } else {
    model.messageHandler()->setLogLevel(2);
    model.solver()->messageHandler()->setLogLevel(1);
  }
  //model.messageHandler()->setLogLevel(2);
  //model.solver()->messageHandler()->setLogLevel(2);
  //model.setPrintFrequency(50);
  //#define DEBUG_CUTS
#ifdef DEBUG_CUTS
  // Set up debugger by name (only if no preprocesing)
  if (!preProcess) {
    std::string problemName ;
    model.solver()->getStrParam(OsiProbName,problemName) ;
    model.solver()->activateRowCutDebugger(problemName.c_str()) ;
  }
#endif
  // Do complete search
  
  model.branchAndBound();

  std::cout<<mpsFileName<<" took "<<CoinCpuTime()-time1<<" seconds, "
	   <<model.getNodeCount()<<" nodes with objective "
	   <<model.getObjValue()
	   <<(!model.status() ? " Finished" : " Not finished")
	   <<std::endl;

  // Print more statistics
  std::cout<<"Cuts at root node changed objective from "<<model.getContinuousObjective()
	   <<" to "<<model.rootObjectiveAfterCuts()<<std::endl;

  for (iGenerator=0;iGenerator<numberGenerators;iGenerator++) {
    CbcCutGenerator * generator = model.cutGenerator(iGenerator);
    std::cout<<generator->cutGeneratorName()<<" was tried "
	     <<generator->numberTimesEntered()<<" times and created "
	     <<generator->numberCutsInTotal()<<" cuts of which "
	     <<generator->numberCutsActive()<<" were active after adding rounds of cuts";
    if (generator->timing())
      std::cout<<" ( "<<generator->timeInCutGenerator()<<" seconds)"<<std::endl;
    else
      std::cout<<std::endl;
  }
  // Print solution if finished - we can't get names from Osi! - so get from OsiClp

  if (model.getMinimizationObjValue()<1.0e50) {
    // post process
    OsiSolverInterface * solver;
    if (preProcess) {
      process.postProcess(*model.solver());
      // Solution now back in solver1
      solver = & solver1;
    } else {
      solver = model.solver();
    }
    int numberColumns = solver->getNumCols();
    
    const double * solution = solver->getColSolution();

    // Get names from solver1 (as OsiSolverInterface may lose)
    std::vector<std::string> columnNames = *solver1.getModelPtr()->columnNames();
    
    int iColumn;
    std::cout<<std::setiosflags(std::ios::fixed|std::ios::showpoint)<<std::setw(14);
    
    std::cout<<"--------------------------------------"<<std::endl;
    for (iColumn=0;iColumn<numberColumns;iColumn++) {
      double value=solution[iColumn];
      if (fabs(value)>1.0e-7&&solver->isInteger(iColumn)) {
	std::cout<<std::setw(6)<<iColumn<<" "
                 <<columnNames[iColumn]<<" "
                 <<value<<std::endl;
	solverSave.setColLower(iColumn,value);
	solverSave.setColUpper(iColumn,value);
      }
    }
    std::cout<<"--------------------------------------"<<std::endl;
  
    std::cout<<std::resetiosflags(std::ios::fixed|std::ios::showpoint|std::ios::scientific);
    solverSave.initialSolve();
  }
  return 0;
}