athos@2146: #include <lemon/lp.h>
athos@2149: #include "test_tools.h"
athos@2146: 
athos@2146: using namespace lemon;
athos@2146: 
athos@2149: void solveAndCheck(Mip& lp, LpSolverBase::SolutionStatus stat, 
athos@2149: 		   double exp_opt) {
athos@2149:   using std::string;
athos@2149:   lp.solve();
athos@2149:   //int decimal,sign;
athos@2149:   std::ostringstream buf;
athos@2149:   buf << "Primalstatus should be: " << int(stat)<<" and it is "<<int(lp.primalStatus());
athos@2146: 
athos@2149:   //  itoa(stat,buf1, 10);
athos@2149:   check(lp.primalStatus()==stat, buf.str());
athos@2149: 
athos@2149:   if (stat ==  LpSolverBase::OPTIMAL) {
athos@2149:     std::ostringstream buf;
athos@2149:     buf << "Wrong optimal value: the right optimum is " << exp_opt; 
athos@2149:     check(std::abs(lp.primalValue()-exp_opt) < 1e-3, buf.str());
athos@2149:     //+ecvt(exp_opt,2)
athos@2149:   }
athos@2149: }
athos@2149: 
athos@2149: void aTest(Mip& mip)
athos@2149: {
athos@2149:  //The following example is very simple
athos@2149: 
athos@2149:   typedef Mip::Row Row;
athos@2149:   typedef Mip::Col Col;
athos@2149: 
athos@2149: 
athos@2149:   Col x1 = mip.addCol();
athos@2149:   Col x2 = mip.addCol();
athos@2149: 
athos@2149: 
athos@2149: 
athos@2149:   //Constraints
athos@2149:   mip.addRow(2*x1+x2 <=2);  
athos@2149:   mip.addRow(x1-2*x2 <=0);  
athos@2149: 
athos@2149:   //Nonnegativity of the variable x1
athos@2149:   mip.colLowerBound(x1, 0);
athos@2149: 
athos@2149: 
athos@2149: 
athos@2149:   //Objective function
athos@2149:   mip.setObj(x1);
athos@2149: 
athos@2149:   mip.max();
athos@2149: 
athos@2149: 
athos@2149:   //Maximization of x1
athos@2149:   //over the triangle with vertices
athos@2149:   double expected_opt=4.0/5.0;
athos@2149:   solveAndCheck(mip, Mip::OPTIMAL, expected_opt);
athos@2149: 
athos@2149:   //Restrict x2 to integer
athos@2149:   mip.colType(x2,Mip::INTEGER);  
athos@2149:   expected_opt=1.0/2.0;
athos@2149:   solveAndCheck(mip, Mip::OPTIMAL, expected_opt);
athos@2149: 
athos@2149: 
athos@2149:   //Restrict both to integer
athos@2149:   mip.colType(x1,Mip::INTEGER);  
athos@2149:   expected_opt=0;
athos@2149:   solveAndCheck(mip, Mip::OPTIMAL, expected_opt);
athos@2149: 
athos@2149:  
athos@2149: 
athos@2149: }
athos@2149: 
athos@2149: 
athos@2149: int main() 
athos@2149: {
athos@2146: 
athos@2147: #ifdef HAVE_GLPK
athos@2149:   MipGlpk mip1;
athos@2149:   aTest(mip1);
athos@2147: #endif
athos@2146: 
athos@2147:   return 0;
athos@2146: 
athos@2146: }