/* $Id$ */ // Copyright (C) 2004, International Business Machines // Corporation and others. All Rights Reserved. // This code is licensed under the terms of the Eclipse Public License (EPL). // This is a simple example to create a model by row #include "ClpSimplex.hpp" #include "CoinHelperFunctions.hpp" #include "CoinTime.hpp" #include "CoinBuild.hpp" #include "CoinModel.hpp" #include #include int main(int argc, const char *argv[]) { #if COIN_BIG_INDEX<2 try { // Empty model ClpSimplex model; // Objective - just nonzeros int objIndex[] = {0, 2}; double objValue[] = {1.0, 4.0}; // Upper bounds - as dense vector double upper[] = {2.0, COIN_DBL_MAX, 4.0}; // Create space for 3 columns model.resize(0, 3); // Fill in int i; // Virtuous way // First objective for (i = 0; i < 2; i++) model.setObjectiveCoefficient(objIndex[i], objValue[i]); // Now bounds (lower will be zero by default but do again) for (i = 0; i < 3; i++) { model.setColumnLower(i, 0.0); model.setColumnUpper(i, upper[i]); } /* We could also have done in non-virtuous way e.g. double * objective = model.objective(); and then set directly */ // Faster to add rows all at once - but this is easier to show // Now add row 1 as >= 2.0 int row1Index[] = {0, 2}; double row1Value[] = {1.0, 1.0}; model.addRow(2, row1Index, row1Value, 2.0, COIN_DBL_MAX); // Now add row 2 as == 1.0 int row2Index[] = {0, 1, 2}; double row2Value[] = {1.0, -5.0, 1.0}; model.addRow(3, row2Index, row2Value, 1.0, 1.0); // solve model.dual(); /* Adding one row at a time has a significant overhead so let's try a more complicated but faster way First time adding in 10000 rows one by one */ model.allSlackBasis(); ClpSimplex modelSave = model; double time1 = CoinCpuTime(); int k; for (k = 0; k < 10000; k++) { int row2Index[] = {0, 1, 2}; double row2Value[] = {1.0, -5.0, 1.0}; model.addRow(3, row2Index, row2Value, 1.0, 1.0); } printf("Time for 10000 addRow is %g\n", CoinCpuTime() - time1); model.dual(); model = modelSave; // Now use build CoinBuild buildObject; time1 = CoinCpuTime(); for (k = 0; k < 10000; k++) { int row2Index[] = {0, 1, 2}; double row2Value[] = {1.0, -5.0, 1.0}; buildObject.addRow(3, row2Index, row2Value, 1.0, 1.0); } model.addRows(buildObject); printf("Time for 10000 addRow using CoinBuild is %g\n", CoinCpuTime() - time1); model.dual(); model = modelSave; int del[] = {0, 1, 2}; model.deleteRows(2, del); // Now use build +-1 CoinBuild buildObject2; time1 = CoinCpuTime(); for (k = 0; k < 10000; k++) { int row2Index[] = {0, 1, 2}; double row2Value[] = {1.0, -1.0, 1.0}; buildObject2.addRow(3, row2Index, row2Value, 1.0, 1.0); } model.addRows(buildObject2, true); printf("Time for 10000 addRow using CoinBuild+-1 is %g\n", CoinCpuTime() - time1); model.dual(); model = modelSave; model.deleteRows(2, del); // Now use build +-1 CoinModel modelObject2; time1 = CoinCpuTime(); for (k = 0; k < 10000; k++) { int row2Index[] = {0, 1, 2}; double row2Value[] = {1.0, -1.0, 1.0}; modelObject2.addRow(3, row2Index, row2Value, 1.0, 1.0); } model.addRows(modelObject2, true); printf("Time for 10000 addRow using CoinModel+-1 is %g\n", CoinCpuTime() - time1); model.dual(); model = ClpSimplex(); // Now use build +-1 CoinModel modelObject3; time1 = CoinCpuTime(); for (k = 0; k < 10000; k++) { int row2Index[] = {0, 1, 2}; double row2Value[] = {1.0, -1.0, 1.0}; modelObject3.addRow(3, row2Index, row2Value, 1.0, 1.0); } model.loadProblem(modelObject3, true); printf("Time for 10000 addRow using CoinModel load +-1 is %g\n", CoinCpuTime() - time1); model.writeMps("xx.mps"); model.dual(); model = modelSave; // Now use model CoinModel modelObject; time1 = CoinCpuTime(); for (k = 0; k < 10000; k++) { int row2Index[] = {0, 1, 2}; double row2Value[] = {1.0, -5.0, 1.0}; modelObject.addRow(3, row2Index, row2Value, 1.0, 1.0); } model.addRows(modelObject); printf("Time for 10000 addRow using CoinModel is %g\n", CoinCpuTime() - time1); model.dual(); model.writeMps("b.mps"); // Method using least memory - but most complicated time1 = CoinCpuTime(); // Assumes we know exact size of model and matrix // Empty model ClpSimplex model2; { // Create space for 3 columns and 10000 rows int numberRows = 10000; int numberColumns = 3; // This is fully dense - but would not normally be so int numberElements = numberRows * numberColumns; // Arrays will be set to default values model2.resize(numberRows, numberColumns); double * elements = new double [numberElements]; CoinBigIndex * starts = new CoinBigIndex [numberColumns+1]; int * rows = new int [numberElements];; int * lengths = new int[numberColumns]; // Now fill in - totally unsafe but .... // no need as defaults to 0.0 double * columnLower = model2.columnLower(); double * columnUpper = model2.columnUpper(); double * objective = model2.objective(); double * rowLower = model2.rowLower(); double * rowUpper = model2.rowUpper(); // Columns - objective was packed for (k = 0; k < 2; k++) { int iColumn = objIndex[k]; objective[iColumn] = objValue[k]; } for (k = 0; k < numberColumns; k++) columnUpper[k] = upper[k]; // Rows for (k = 0; k < numberRows; k++) { rowLower[k] = 1.0; rowUpper[k] = 1.0; } // Now elements double row2Value[] = {1.0, -5.0, 1.0}; CoinBigIndex put = 0; for (k = 0; k < numberColumns; k++) { starts[k] = put; lengths[k] = numberRows; double value = row2Value[k]; for (int i = 0; i < numberRows; i++) { rows[put] = i; elements[put] = value; put++; } } starts[numberColumns] = put; // assign to matrix CoinPackedMatrix * matrix = new CoinPackedMatrix(true, 0.0, 0.0); matrix->assignMatrix(true, numberRows, numberColumns, numberElements, elements, rows, starts, lengths); ClpPackedMatrix * clpMatrix = new ClpPackedMatrix(matrix); model2.replaceMatrix(clpMatrix, true); printf("Time for 10000 addRow using hand written code is %g\n", CoinCpuTime() - time1); // If matrix is really big could switch off creation of row copy // model2.setSpecialOptions(256); } model2.dual(); model2.writeMps("a.mps"); // Print column solution int numberColumns = model.numberColumns(); // Alternatively getColSolution() double * columnPrimal = model.primalColumnSolution(); // Alternatively getReducedCost() double * columnDual = model.dualColumnSolution(); // Alternatively getColLower() double * columnLower = model.columnLower(); // Alternatively getColUpper() double * columnUpper = model.columnUpper(); // Alternatively getObjCoefficients() double * columnObjective = model.objective(); int iColumn; std::cout << " Primal Dual Lower Upper Cost" << std::endl; for (iColumn = 0; iColumn < numberColumns; iColumn++) { double value; std::cout << std::setw(6) << iColumn << " "; value = columnPrimal[iColumn]; if (fabs(value) < 1.0e5) std::cout << std::setiosflags(std::ios::fixed | std::ios::showpoint) << std::setw(14) << value; else std::cout << std::setiosflags(std::ios::scientific) << std::setw(14) << value; value = columnDual[iColumn]; if (fabs(value) < 1.0e5) std::cout << std::setiosflags(std::ios::fixed | std::ios::showpoint) << std::setw(14) << value; else std::cout << std::setiosflags(std::ios::scientific) << std::setw(14) << value; value = columnLower[iColumn]; if (fabs(value) < 1.0e5) std::cout << std::setiosflags(std::ios::fixed | std::ios::showpoint) << std::setw(14) << value; else std::cout << std::setiosflags(std::ios::scientific) << std::setw(14) << value; value = columnUpper[iColumn]; if (fabs(value) < 1.0e5) std::cout << std::setiosflags(std::ios::fixed | std::ios::showpoint) << std::setw(14) << value; else std::cout << std::setiosflags(std::ios::scientific) << std::setw(14) << value; value = columnObjective[iColumn]; if (fabs(value) < 1.0e5) std::cout << std::setiosflags(std::ios::fixed | std::ios::showpoint) << std::setw(14) << value; else std::cout << std::setiosflags(std::ios::scientific) << std::setw(14) << value; std::cout << std::endl; } std::cout << "--------------------------------------" << std::endl; // Test CoinAssert std::cout << "If Clp compiled without NDEBUG below should give assert, if with NDEBUG or COIN_ASSERT CoinError" << std::endl; model = modelSave; model.deleteRows(2, del); // Deliberate error model.deleteColumns(1, del + 2); // Now use build +-1 CoinBuild buildObject3; time1 = CoinCpuTime(); for (k = 0; k < 10000; k++) { int row2Index[] = {0, 1, 2}; double row2Value[] = {1.0, -1.0, 1.0}; buildObject3.addRow(3, row2Index, row2Value, 1.0, 1.0); } model.addRows(buildObject3, true); } catch (CoinError e) { e.print(); if (e.lineNumber() >= 0) std::cout << "This was from a CoinAssert" << std::endl; } #else printf("addRows not available with COIN_BIG_INDEX=2\n"); #endif return 0; }