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/* $Id: modify.cpp 1662 2011-01-04 17:52:40Z lou $ */
// Copyright (C) 2007, International Business Machines
// Corporation and others. All Rights Reserved.
// This code is licensed under the terms of the Eclipse Public License (EPL).
/*
This example shows the creation of a model from arrays, solution
and then changes to objective and adding a row
*/
#include "ClpSimplex.hpp"
#include "CoinHelperFunctions.hpp"
int main(int argc, const char *argv[])
{
ClpSimplex model;
// model is as exmip1.mps from Data/samples
int numberRows = 5;
int numberColumns = 8;
int numberElements = 14;
// matrix data - column ordered
CoinBigIndex start[9] = {0, 2, 4, 6, 8, 10, 11, 12, 14};
int length[8] = {2, 2, 2, 2, 2, 1, 1, 2};
int rows[14] = {0, 4, 0, 1, 1, 2, 0, 3, 0, 4, 2, 3, 0, 4};
double elements[14] = {3, 5.6, 1, 2, 1.1, 1, -2, 2.8, -1, 1, 1, -1.2, -1, 1.9};
CoinPackedMatrix matrix(true, numberRows, numberColumns, numberElements, elements, rows, start, length);
// rim data
double objective[8] = {1, 0, 0, 0, 2, 0, 0, -1};
double rowLower[5] = {2.5, -COIN_DBL_MAX, 4, 1.8, 3};
double rowUpper[5] = {COIN_DBL_MAX, 2.1, 4, 5, 15};
double colLower[8] = {2.5, 0, 0, 0, 0.5, 0, 0, 0};
double colUpper[8] = {COIN_DBL_MAX, 4.1, 1, 1, 4, COIN_DBL_MAX, COIN_DBL_MAX, 4.3};
// load problem
model.loadProblem(matrix, colLower, colUpper, objective,
rowLower, rowUpper);
// mark integer (really for Cbc/examples/modify.cpp
model.setInteger(2);
model.setInteger(3);
// Solve
model.initialSolve();
// Solution
const double * solution = model.primalColumnSolution();
int i;
for (i = 0; i < numberColumns; i++)
if (solution[i])
printf("Column %d has value %g\n", i, solution[i]);
// Change objective
double * objective2 = model.objective();
objective2[0] = -100.0;
// Solve - primal as primal feasible
model.primal(1);
// Solution (array won't have changed)
for (i = 0; i < numberColumns; i++)
if (solution[i])
printf("Column %d has value %g\n", i, solution[i]);
// Add constraint
int column[8] = {0, 1, 2, 3, 4, 5, 6, 7};
double element2[8] = {1, 1, 1, 1, 1, 1, 1, 1};
model.addRow(8, column, element2, 7.8, COIN_DBL_MAX);
// Solve - dual as dual feasible
model.dual();
/* Solution
This time we have changed arrays of solver so -
array won't have changed as column array and we added a row
- but be on safe side
*/
solution = model.primalColumnSolution();
for (i = 0; i < numberColumns; i++)
if (solution[i])
printf("Column %d has value %g\n", i, solution[i]);
return 0;
}
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