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
Line 
1#include "test_tools.h"
2
3
4#include <lemon/mip_cplex.h>
5#include <lemon/mip_glpk.h>
6
7#ifdef HAVE_CONFIG_H
8#include <config.h>
9#endif
10
11
12
13using namespace lemon;
14
15void solveAndCheck(MipSolverBase& lp, MipSolverBase::SolutionStatus stat,
16                   double exp_opt) {
17  using std::string;
18
19  lp.solve();
20  //int decimal,sign;
21  std::ostringstream buf;
22  buf << "Primalstatus should be: " << int(stat)<<" and it is "<<int(lp.primalStatus());
23
24
25  //  itoa(stat,buf1, 10);
26  check(lp.mipStatus()==stat, buf.str());
27
28  if (stat ==  MipSolverBase::OPTIMAL) {
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
36void aTest(MipSolverBase& mip)
37{
38 //The following example is very simple
39
40
41  typedef MipSolverBase::Row Row;
42  typedef MipSolverBase::Col Col;
43
44
45
46  Col x1 = mip.addCol();
47  Col x2 = mip.addCol();
48
49
50  //Objective function
51  mip.setObj(x1);
52
53  mip.max();
54
55
56  //Unconstrained optimization
57  mip.solve();
58  //Check it out!
59
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
70  //over the triangle with vertices (0,0),(4/5,2/5),(0,2)
71  double expected_opt=4.0/5.0;
72  solveAndCheck(mip, MipSolverBase::OPTIMAL, expected_opt);
73
74  //Restrict x2 to integer
75  mip.colType(x2,MipSolverBase::LEMON_INTEGER); 
76  expected_opt=1.0/2.0;
77  solveAndCheck(mip, MipSolverBase::OPTIMAL, expected_opt);
78
79
80  //Restrict both to integer
81  mip.colType(x1,MipSolverBase::LEMON_INTEGER); 
82  expected_opt=0;
83  solveAndCheck(mip, MipSolverBase::OPTIMAL, expected_opt);
84
85 
86
87}
88
89
90int main()
91{
92
93#ifdef HAVE_GLPK
94  MipGlpk mip1;
95  aTest(mip1);
96#endif
97
98#ifdef HAVE_CPLEX
99  MipCplex mip2;
100  aTest(mip2);
101#endif
102
103  return 0;
104
105}
Note: See TracBrowser for help on using the repository browser.