COIN-OR::LEMON - Graph Library

source: lemon-0.x/test/mip_test.cc @ 2223:590c1b663a27

Last change on this file since 2223:590c1b663a27 was 2221:c7261e981330, checked in by athos, 13 years ago

Minor changes.

File size: 1.8 KB
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[2149]1#include "test_tools.h"
[2146]2
[2218]3
4#include <lemon/mip_cplex.h>
5#include <lemon/mip_glpk.h>
[2221]6
7#ifdef HAVE_CONFIG_H
8#include <config.h>
9#endif
10
11
[2218]12
[2146]13using namespace lemon;
14
[2218]15void solveAndCheck(MipSolverBase& lp, MipSolverBase::SolutionStatus stat,
[2149]16                   double exp_opt) {
17  using std::string;
[2218]18
[2149]19  lp.solve();
20  //int decimal,sign;
21  std::ostringstream buf;
22  buf << "Primalstatus should be: " << int(stat)<<" and it is "<<int(lp.primalStatus());
[2146]23
[2218]24
[2149]25  //  itoa(stat,buf1, 10);
[2213]26  check(lp.mipStatus()==stat, buf.str());
[2149]27
[2218]28  if (stat ==  MipSolverBase::OPTIMAL) {
[2149]29    std::ostringstream buf;
30    buf << "Wrong optimal value: the right optimum is " << exp_opt;
31    check(std::abs(lp.primalValue()-exp_opt) < 1e-3, buf.str());
32    //+ecvt(exp_opt,2)
33  }
34}
35
[2218]36void aTest(MipSolverBase& mip)
[2149]37{
38 //The following example is very simple
39
[2218]40
41  typedef MipSolverBase::Row Row;
42  typedef MipSolverBase::Col Col;
43
[2149]44
45
46  Col x1 = mip.addCol();
47  Col x2 = mip.addCol();
48
49
[2213]50  //Objective function
51  mip.setObj(x1);
52
53  mip.max();
54
55
56  //Unconstrained optimization
57  mip.solve();
58  //Check it out!
59
[2149]60  //Constraints
61  mip.addRow(2*x1+x2 <=2); 
62  mip.addRow(x1-2*x2 <=0); 
63
64  //Nonnegativity of the variable x1
65  mip.colLowerBound(x1, 0);
66
67
68
69  //Maximization of x1
[2221]70  //over the triangle with vertices (0,0),(4/5,2/5),(0,2)
[2149]71  double expected_opt=4.0/5.0;
[2218]72  solveAndCheck(mip, MipSolverBase::OPTIMAL, expected_opt);
[2149]73
74  //Restrict x2 to integer
[2218]75  mip.colType(x2,MipSolverBase::LEMON_INTEGER); 
[2149]76  expected_opt=1.0/2.0;
[2218]77  solveAndCheck(mip, MipSolverBase::OPTIMAL, expected_opt);
[2149]78
79
80  //Restrict both to integer
[2218]81  mip.colType(x1,MipSolverBase::LEMON_INTEGER); 
[2149]82  expected_opt=0;
[2218]83  solveAndCheck(mip, MipSolverBase::OPTIMAL, expected_opt);
[2149]84
85 
86
87}
88
89
90int main()
91{
[2146]92
[2147]93#ifdef HAVE_GLPK
[2149]94  MipGlpk mip1;
95  aTest(mip1);
[2147]96#endif
[2146]97
[2218]98#ifdef HAVE_CPLEX
99  MipCplex mip2;
100  aTest(mip2);
101#endif
102
[2147]103  return 0;
[2146]104
105}
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