test/mip_test.cc
author Peter Kovacs <kpeter@inf.elte.hu>
Fri, 03 Apr 2009 13:46:16 +0200
changeset 607 9ad8d2122b50
parent 461 08d495d48089
child 537 0fec6a017ead
child 540 9db62975c32b
permissions -rw-r--r--
Separate types for flow and cost values in NetworkSimplex (#234)
     1 /* -*- mode: C++; indent-tabs-mode: nil; -*-
     2  *
     3  * This file is a part of LEMON, a generic C++ optimization library.
     4  *
     5  * Copyright (C) 2003-2008
     6  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
     7  * (Egervary Research Group on Combinatorial Optimization, EGRES).
     8  *
     9  * Permission to use, modify and distribute this software is granted
    10  * provided that this copyright notice appears in all copies. For
    11  * precise terms see the accompanying LICENSE file.
    12  *
    13  * This software is provided "AS IS" with no warranty of any kind,
    14  * express or implied, and with no claim as to its suitability for any
    15  * purpose.
    16  *
    17  */
    18 
    19 #include "test_tools.h"
    20 
    21 
    22 #ifdef HAVE_CONFIG_H
    23 #include <lemon/config.h>
    24 #endif
    25 
    26 #ifdef HAVE_CPLEX
    27 #include <lemon/cplex.h>
    28 #endif
    29 
    30 #ifdef HAVE_GLPK
    31 #include <lemon/glpk.h>
    32 #endif
    33 
    34 
    35 using namespace lemon;
    36 
    37 void solveAndCheck(MipSolver& mip, MipSolver::ProblemType stat,
    38                    double exp_opt) {
    39   using std::string;
    40 
    41   mip.solve();
    42   //int decimal,sign;
    43   std::ostringstream buf;
    44   buf << "Type should be: " << int(stat)<<" and it is "<<int(mip.type());
    45 
    46 
    47   //  itoa(stat,buf1, 10);
    48   check(mip.type()==stat, buf.str());
    49 
    50   if (stat ==  MipSolver::OPTIMAL) {
    51     std::ostringstream sbuf;
    52     buf << "Wrong optimal value: the right optimum is " << exp_opt;
    53     check(std::abs(mip.solValue()-exp_opt) < 1e-3, sbuf.str());
    54     //+ecvt(exp_opt,2)
    55   }
    56 }
    57 
    58 void aTest(MipSolver& mip)
    59 {
    60  //The following example is very simple
    61 
    62 
    63   typedef MipSolver::Row Row;
    64   typedef MipSolver::Col Col;
    65 
    66 
    67 
    68   Col x1 = mip.addCol();
    69   Col x2 = mip.addCol();
    70 
    71 
    72   //Objective function
    73   mip.obj(x1);
    74 
    75   mip.max();
    76 
    77 
    78   //Unconstrained optimization
    79   mip.solve();
    80   //Check it out!
    81 
    82   //Constraints
    83   mip.addRow(2*x1+x2 <=2);
    84   mip.addRow(x1-2*x2 <=0);
    85 
    86   //Nonnegativity of the variable x1
    87   mip.colLowerBound(x1, 0);
    88 
    89   //Maximization of x1
    90   //over the triangle with vertices (0,0),(4/5,2/5),(0,2)
    91   double expected_opt=4.0/5.0;
    92   solveAndCheck(mip, MipSolver::OPTIMAL, expected_opt);
    93 
    94   //Restrict x2 to integer
    95   mip.colType(x2,MipSolver::INTEGER);
    96   expected_opt=1.0/2.0;
    97   solveAndCheck(mip, MipSolver::OPTIMAL, expected_opt);
    98 
    99 
   100   //Restrict both to integer
   101   mip.colType(x1,MipSolver::INTEGER);
   102   expected_opt=0;
   103   solveAndCheck(mip, MipSolver::OPTIMAL, expected_opt);
   104 
   105 
   106 
   107 }
   108 
   109 
   110 int main()
   111 {
   112 
   113 #ifdef HAVE_GLPK
   114   {
   115     GlpkMip mip1;
   116     aTest(mip1);
   117   }
   118 #endif
   119 
   120 #ifdef HAVE_CPLEX
   121   try {
   122     CplexMip mip2;
   123     aTest(mip2);
   124   } catch (CplexEnv::LicenseError& error) {
   125 #ifdef LEMON_FORCE_CPLEX_CHECK
   126     check(false, error.what());
   127 #else
   128     std::cerr << error.what() << std::endl;
   129     std::cerr << "Cplex license check failed, lp check skipped" << std::endl;
   130 #endif
   131   }
   132 #endif
   133 
   134   return 0;
   135 
   136 }