[2144] | 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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[2218] | 19 | #ifndef LEMON_MIP_GLPK_CC |
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| 20 | #define LEMON_MIP_GLPK_CC |
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[2144] | 21 | |
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| 22 | ///\file |
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[2218] | 23 | ///\brief Implementation of the LEMON-GLPK mip solver interface. |
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[2144] | 24 | |
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| 25 | #include <lemon/mip_glpk.h> |
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| 26 | |
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| 27 | namespace lemon { |
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| 28 | |
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| 29 | MipGlpk::MipGlpk() { |
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| 30 | lpx_set_class(lp,LPX_MIP); |
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| 31 | } |
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[2148] | 32 | |
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[2149] | 33 | void MipGlpk::_colType(int i, MipGlpk::ColTypes col_type){ |
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[2148] | 34 | switch (col_type){ |
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[2218] | 35 | case LEMON_INTEGER: |
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[2148] | 36 | lpx_set_col_kind(lp,i,LPX_IV); |
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| 37 | break; |
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| 38 | case REAL: |
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| 39 | lpx_set_col_kind(lp,i,LPX_CV); |
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| 40 | break; |
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[2149] | 41 | default:; |
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[2148] | 42 | //FIXME problem |
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[2144] | 43 | } |
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| 44 | } |
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| 45 | |
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[2149] | 46 | MipGlpk::ColTypes MipGlpk::_colType(int i){ |
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[2148] | 47 | switch (lpx_get_col_kind(lp,i)){ |
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| 48 | case LPX_IV: |
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[2218] | 49 | return LEMON_INTEGER;//Or binary |
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[2148] | 50 | case LPX_CV: |
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| 51 | return REAL; |
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| 52 | default: |
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| 53 | return REAL;//Error! |
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[2144] | 54 | } |
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[2148] | 55 | |
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[2144] | 56 | } |
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| 57 | |
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| 58 | LpGlpk::SolveExitStatus MipGlpk::_solve(){ |
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| 59 | int result = lpx_simplex(lp); |
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[2213] | 60 | // |
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| 61 | if (lpx_get_status(lp)==LPX_OPT){ |
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| 62 | //Maybe we could try the routine lpx_intopt(lp), a revised |
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| 63 | //version of lpx_integer |
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| 64 | result = lpx_integer(lp); |
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| 65 | switch (result){ |
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[2144] | 66 | case LPX_E_OK: |
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[2213] | 67 | return SOLVED; |
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[2144] | 68 | default: |
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[2213] | 69 | return UNSOLVED; |
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| 70 | } |
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| 71 | |
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[2144] | 72 | } |
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[2213] | 73 | return UNSOLVED; |
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[2144] | 74 | } |
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[2185] | 75 | |
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| 76 | |
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| 77 | LpGlpk::SolutionStatus MipGlpk::_getMipStatus(){ |
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| 78 | |
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[2213] | 79 | if (lpx_get_status(lp)==LPX_OPT){ |
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| 80 | //Meg kell nezni: ha az LP is infinite, akkor ez is, ha az is |
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| 81 | //infeasible, akkor ez is, de ez lehet maskepp is infeasible. |
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| 82 | int stat= lpx_mip_status(lp); |
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| 83 | |
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| 84 | switch (stat) { |
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| 85 | case LPX_I_UNDEF://Undefined (no solve has been run yet) |
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| 86 | return UNDEFINED; |
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| 87 | case LPX_I_NOFEAS://There is no feasible integral solution |
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| 88 | return INFEASIBLE; |
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| 89 | // case LPX_UNBND://Unbounded |
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| 90 | // return INFINITE; |
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| 91 | case LPX_I_FEAS://Feasible |
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| 92 | return FEASIBLE; |
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| 93 | case LPX_I_OPT://Feasible |
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| 94 | return OPTIMAL; |
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| 95 | default: |
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[2185] | 96 | return UNDEFINED; //to avoid gcc warning |
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| 97 | //FIXME error |
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[2213] | 98 | } |
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[2185] | 99 | } |
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[2213] | 100 | else |
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| 101 | return UNDEFINED; //Maybe we could refine this: what does the LP |
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| 102 | //relaxation look like |
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| 103 | |
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[2185] | 104 | } |
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| 105 | |
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[2144] | 106 | MipGlpk::Value MipGlpk::_getPrimal(int i){ |
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| 107 | return lpx_mip_col_val(lp,i); |
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| 108 | } |
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| 109 | |
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| 110 | MipGlpk::Value MipGlpk::_getPrimalValue(){ |
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| 111 | return lpx_mip_obj_val(lp); |
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| 112 | } |
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[2218] | 113 | } //END OF NAMESPACE LEMON |
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[2144] | 114 | |
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[2218] | 115 | #endif //END OF MIP_GLPK_CC |
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