| 1 | /* -*- C++ -*- |
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| 2 | * |
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| 3 | * This file is a part of LEMON, a generic C++ optimization library |
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| 4 | * |
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| 5 | * Copyright (C) 2003-2006 |
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| 6 | * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
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| 7 | * (Egervary Research Group on Combinatorial Optimization, EGRES). |
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| 8 | * |
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| 9 | * Permission to use, modify and distribute this software is granted |
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| 10 | * provided that this copyright notice appears in all copies. For |
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| 11 | * precise terms see the accompanying LICENSE file. |
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| 12 | * |
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| 13 | * This software is provided "AS IS" with no warranty of any kind, |
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| 14 | * express or implied, and with no claim as to its suitability for any |
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| 15 | * purpose. |
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| 16 | * |
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| 17 | */ |
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| 18 | |
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| 19 | #ifndef LEMON_MIP_CPLEX_CC |
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| 20 | #define LEMON_MIP_CPLEX_CC |
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| 21 | |
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| 22 | ///\file |
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| 23 | ///\brief Implementation of the LEMON-CPLEX mip solver interface. |
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| 24 | |
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| 25 | #include <lemon/mip_cplex.h> |
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| 26 | |
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| 27 | namespace lemon { |
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| 28 | |
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| 29 | MipCplex::MipCplex() { |
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| 30 | //This is unnecessary: setting integrality constraints on |
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| 31 | //variables will set this, too |
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| 32 | |
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| 33 | ///\todo The constant CPXPROB_MIP is |
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| 34 | ///called CPXPROB_MILP in later versions |
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| 35 | CPXchgprobtype( env, lp, CPXPROB_MIP); |
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| 36 | } |
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| 37 | |
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| 38 | void MipCplex::_colType(int i, MipCplex::ColTypes col_type){ |
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| 39 | |
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| 40 | // Note If a variable is to be changed to binary, a call to CPXchgbds |
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| 41 | // should also be made to change the bounds to 0 and 1. |
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| 42 | |
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| 43 | int indices[1]; |
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| 44 | indices[0]=i; |
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| 45 | char ctype[1]; |
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| 46 | switch (col_type){ |
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| 47 | case INTEGER: |
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| 48 | ctype[0]=CPX_INTEGER;//'I' |
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| 49 | break; |
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| 50 | case REAL: |
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| 51 | ctype[0]=CPX_CONTINUOUS ;//'C' |
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| 52 | break; |
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| 53 | default:; |
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| 54 | //FIXME problem |
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| 55 | } |
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| 56 | CPXchgctype (env, lp, 1, indices, ctype); |
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| 57 | } |
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| 58 | |
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| 59 | MipCplex::ColTypes MipCplex::_colType(int i){ |
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| 60 | |
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| 61 | char ctype[1]; |
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| 62 | status = CPXgetctype (env, lp, ctype, i, i); |
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| 63 | std::cout<<"Kukucska: "<<INTEGER<<std::endl; |
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| 64 | return REAL; |
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| 65 | // switch (ctype[0]){ |
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| 66 | |
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| 67 | // case CPX_INTEGER: |
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| 68 | // return INTEGER; |
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| 69 | // case CPX_CONTINUOUS: |
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| 70 | // return REAL; |
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| 71 | // default: |
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| 72 | // return REAL;//Error! |
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| 73 | // } |
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| 74 | |
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| 75 | } |
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| 76 | |
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| 77 | LpCplex::SolveExitStatus MipCplex::_solve(){ |
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| 78 | |
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| 79 | status = CPXmipopt (env, lp); |
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| 80 | if (status==0) |
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| 81 | return SOLVED; |
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| 82 | else |
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| 83 | return UNSOLVED; |
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| 84 | |
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| 85 | } |
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| 86 | |
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| 87 | |
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| 88 | LpCplex::SolutionStatus MipCplex::_getMipStatus(){ |
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| 89 | |
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| 90 | int stat = CPXgetstat(env, lp); |
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| 91 | |
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| 92 | //Fortunately, MIP statuses did not change for cplex 8.0 |
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| 93 | switch (stat) |
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| 94 | { |
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| 95 | case CPXMIP_OPTIMAL: |
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| 96 | return OPTIMAL; |
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| 97 | //This also exists in later issues |
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| 98 | // case CPXMIP_UNBOUNDED: |
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| 99 | //return INFINITE; |
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| 100 | case CPXMIP_INFEASIBLE: |
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| 101 | return INFEASIBLE; |
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| 102 | default: |
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| 103 | return UNDEFINED; |
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| 104 | } |
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| 105 | //Unboundedness not treated well: the following is from cplex 9.0 doc |
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| 106 | // About Unboundedness |
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| 107 | |
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| 108 | // The treatment of models that are unbounded involves a few |
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| 109 | // subtleties. Specifically, a declaration of unboundedness means that |
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| 110 | // ILOG CPLEX has determined that the model has an unbounded |
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| 111 | // ray. Given any feasible solution x with objective z, a multiple of |
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| 112 | // the unbounded ray can be added to x to give a feasible solution |
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| 113 | // with objective z-1 (or z+1 for maximization models). Thus, if a |
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| 114 | // feasible solution exists, then the optimal objective is |
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| 115 | // unbounded. Note that ILOG CPLEX has not necessarily concluded that |
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| 116 | // a feasible solution exists. Users can call the routine CPXsolninfo |
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| 117 | // to determine whether ILOG CPLEX has also concluded that the model |
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| 118 | // has a feasible solution. |
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| 119 | |
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| 120 | } |
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| 121 | |
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| 122 | MipCplex::Value MipCplex::_getPrimal(int i){ |
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| 123 | Value x; |
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| 124 | CPXgetmipx(env, lp, &x, i, i); |
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| 125 | return x; |
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| 126 | } |
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| 127 | |
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| 128 | MipCplex::Value MipCplex::_getPrimalValue(){ |
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| 129 | Value objval; |
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| 130 | status = CPXgetmipobjval(env, lp, &objval); |
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| 131 | return objval; |
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| 132 | } |
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| 133 | } //END OF NAMESPACE LEMON |
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| 134 | |
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| 135 | #endif //END OF MIP_CPLEX_CC |
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