| 1 | /* -*- mode: C++; indent-tabs-mode: nil; -*- |
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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) 2003-2009 |
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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 | #include <iostream> |
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| 20 | #include <vector> |
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| 21 | #include <cstring> |
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| 22 | |
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| 23 | #include <lemon/cplex.h> |
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| 24 | |
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| 25 | extern "C" { |
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| 26 | #include <ilcplex/cplex.h> |
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| 27 | } |
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| 28 | |
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| 29 | |
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| 30 | ///\file |
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| 31 | ///\brief Implementation of the LEMON-CPLEX lp solver interface. |
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| 32 | namespace lemon { |
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| 33 | |
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| 34 | CplexEnv::LicenseError::LicenseError(int status) { |
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| 35 | if (!CPXgeterrorstring(0, status, _message)) { |
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| 36 | std::strcpy(_message, "Cplex unknown error"); |
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| 37 | } |
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| 38 | } |
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| 39 | |
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| 40 | CplexEnv::CplexEnv() { |
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| 41 | int status; |
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| 42 | _cnt = new int; |
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| 43 | _env = CPXopenCPLEX(&status); |
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| 44 | if (_env == 0) { |
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| 45 | delete _cnt; |
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| 46 | _cnt = 0; |
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| 47 | throw LicenseError(status); |
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| 48 | } |
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| 49 | } |
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| 50 | |
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| 51 | CplexEnv::CplexEnv(const CplexEnv& other) { |
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| 52 | _env = other._env; |
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| 53 | _cnt = other._cnt; |
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| 54 | ++(*_cnt); |
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| 55 | } |
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| 56 | |
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| 57 | CplexEnv& CplexEnv::operator=(const CplexEnv& other) { |
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| 58 | _env = other._env; |
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| 59 | _cnt = other._cnt; |
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| 60 | ++(*_cnt); |
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| 61 | return *this; |
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| 62 | } |
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| 63 | |
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| 64 | CplexEnv::~CplexEnv() { |
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| 65 | --(*_cnt); |
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| 66 | if (*_cnt == 0) { |
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| 67 | delete _cnt; |
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| 68 | CPXcloseCPLEX(&_env); |
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| 69 | } |
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| 70 | } |
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| 71 | |
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| 72 | CplexBase::CplexBase() : LpBase() { |
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| 73 | int status; |
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| 74 | _prob = CPXcreateprob(cplexEnv(), &status, "Cplex problem"); |
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| 75 | } |
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| 76 | |
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| 77 | CplexBase::CplexBase(const CplexEnv& env) |
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| 78 | : LpBase(), _env(env) { |
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| 79 | int status; |
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| 80 | _prob = CPXcreateprob(cplexEnv(), &status, "Cplex problem"); |
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| 81 | } |
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| 82 | |
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| 83 | CplexBase::CplexBase(const CplexBase& cplex) |
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| 84 | : LpBase() { |
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| 85 | int status; |
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| 86 | _prob = CPXcloneprob(cplexEnv(), cplex._prob, &status); |
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| 87 | rows = cplex.rows; |
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| 88 | cols = cplex.cols; |
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| 89 | } |
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| 90 | |
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| 91 | CplexBase::~CplexBase() { |
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| 92 | CPXfreeprob(cplexEnv(),&_prob); |
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| 93 | } |
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| 94 | |
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| 95 | int CplexBase::_addCol() { |
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| 96 | int i = CPXgetnumcols(cplexEnv(), _prob); |
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| 97 | double lb = -INF, ub = INF; |
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| 98 | CPXnewcols(cplexEnv(), _prob, 1, 0, &lb, &ub, 0, 0); |
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| 99 | return i; |
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| 100 | } |
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| 101 | |
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| 102 | |
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| 103 | int CplexBase::_addRow() { |
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| 104 | int i = CPXgetnumrows(cplexEnv(), _prob); |
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| 105 | const double ub = INF; |
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| 106 | const char s = 'L'; |
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| 107 | CPXnewrows(cplexEnv(), _prob, 1, &ub, &s, 0, 0); |
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| 108 | return i; |
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| 109 | } |
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| 110 | |
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| 111 | |
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| 112 | void CplexBase::_eraseCol(int i) { |
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| 113 | CPXdelcols(cplexEnv(), _prob, i, i); |
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| 114 | } |
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| 115 | |
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| 116 | void CplexBase::_eraseRow(int i) { |
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| 117 | CPXdelrows(cplexEnv(), _prob, i, i); |
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| 118 | } |
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| 119 | |
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| 120 | void CplexBase::_eraseColId(int i) { |
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| 121 | cols.eraseIndex(i); |
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| 122 | cols.shiftIndices(i); |
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| 123 | } |
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| 124 | void CplexBase::_eraseRowId(int i) { |
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| 125 | rows.eraseIndex(i); |
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| 126 | rows.shiftIndices(i); |
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| 127 | } |
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| 128 | |
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| 129 | void CplexBase::_getColName(int col, std::string &name) const { |
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| 130 | int size; |
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| 131 | CPXgetcolname(cplexEnv(), _prob, 0, 0, 0, &size, col, col); |
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| 132 | if (size == 0) { |
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| 133 | name.clear(); |
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| 134 | return; |
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| 135 | } |
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| 136 | |
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| 137 | size *= -1; |
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| 138 | std::vector<char> buf(size); |
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| 139 | char *cname; |
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| 140 | int tmp; |
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| 141 | CPXgetcolname(cplexEnv(), _prob, &cname, &buf.front(), size, |
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| 142 | &tmp, col, col); |
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| 143 | name = cname; |
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| 144 | } |
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| 145 | |
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| 146 | void CplexBase::_setColName(int col, const std::string &name) { |
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| 147 | char *cname; |
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| 148 | cname = const_cast<char*>(name.c_str()); |
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| 149 | CPXchgcolname(cplexEnv(), _prob, 1, &col, &cname); |
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| 150 | } |
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| 151 | |
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| 152 | int CplexBase::_colByName(const std::string& name) const { |
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| 153 | int index; |
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| 154 | if (CPXgetcolindex(cplexEnv(), _prob, |
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| 155 | const_cast<char*>(name.c_str()), &index) == 0) { |
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| 156 | return index; |
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| 157 | } |
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| 158 | return -1; |
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| 159 | } |
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| 160 | |
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| 161 | void CplexBase::_getRowName(int row, std::string &name) const { |
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| 162 | int size; |
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| 163 | CPXgetrowname(cplexEnv(), _prob, 0, 0, 0, &size, row, row); |
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| 164 | if (size == 0) { |
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| 165 | name.clear(); |
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| 166 | return; |
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| 167 | } |
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| 168 | |
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| 169 | size *= -1; |
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| 170 | std::vector<char> buf(size); |
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| 171 | char *cname; |
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| 172 | int tmp; |
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| 173 | CPXgetrowname(cplexEnv(), _prob, &cname, &buf.front(), size, |
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| 174 | &tmp, row, row); |
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| 175 | name = cname; |
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| 176 | } |
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| 177 | |
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| 178 | void CplexBase::_setRowName(int row, const std::string &name) { |
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| 179 | char *cname; |
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| 180 | cname = const_cast<char*>(name.c_str()); |
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| 181 | CPXchgrowname(cplexEnv(), _prob, 1, &row, &cname); |
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| 182 | } |
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| 183 | |
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| 184 | int CplexBase::_rowByName(const std::string& name) const { |
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| 185 | int index; |
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| 186 | if (CPXgetrowindex(cplexEnv(), _prob, |
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| 187 | const_cast<char*>(name.c_str()), &index) == 0) { |
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| 188 | return index; |
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| 189 | } |
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| 190 | return -1; |
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| 191 | } |
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| 192 | |
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| 193 | void CplexBase::_setRowCoeffs(int i, ExprIterator b, |
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| 194 | ExprIterator e) |
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| 195 | { |
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| 196 | std::vector<int> indices; |
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| 197 | std::vector<int> rowlist; |
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| 198 | std::vector<Value> values; |
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| 199 | |
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| 200 | for(ExprIterator it=b; it!=e; ++it) { |
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| 201 | indices.push_back(it->first); |
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| 202 | values.push_back(it->second); |
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| 203 | rowlist.push_back(i); |
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| 204 | } |
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| 205 | |
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| 206 | CPXchgcoeflist(cplexEnv(), _prob, values.size(), |
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| 207 | &rowlist.front(), &indices.front(), &values.front()); |
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| 208 | } |
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| 209 | |
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| 210 | void CplexBase::_getRowCoeffs(int i, InsertIterator b) const { |
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| 211 | int tmp1, tmp2, tmp3, length; |
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| 212 | CPXgetrows(cplexEnv(), _prob, &tmp1, &tmp2, 0, 0, 0, &length, i, i); |
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| 213 | |
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| 214 | length = -length; |
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| 215 | std::vector<int> indices(length); |
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| 216 | std::vector<double> values(length); |
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| 217 | |
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| 218 | CPXgetrows(cplexEnv(), _prob, &tmp1, &tmp2, |
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| 219 | &indices.front(), &values.front(), |
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| 220 | length, &tmp3, i, i); |
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| 221 | |
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| 222 | for (int i = 0; i < length; ++i) { |
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| 223 | *b = std::make_pair(indices[i], values[i]); |
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| 224 | ++b; |
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| 225 | } |
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| 226 | } |
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| 227 | |
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| 228 | void CplexBase::_setColCoeffs(int i, ExprIterator b, ExprIterator e) { |
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| 229 | std::vector<int> indices; |
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| 230 | std::vector<int> collist; |
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| 231 | std::vector<Value> values; |
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| 232 | |
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| 233 | for(ExprIterator it=b; it!=e; ++it) { |
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| 234 | indices.push_back(it->first); |
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| 235 | values.push_back(it->second); |
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| 236 | collist.push_back(i); |
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| 237 | } |
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| 238 | |
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| 239 | CPXchgcoeflist(cplexEnv(), _prob, values.size(), |
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| 240 | &indices.front(), &collist.front(), &values.front()); |
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| 241 | } |
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| 242 | |
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| 243 | void CplexBase::_getColCoeffs(int i, InsertIterator b) const { |
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| 244 | |
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| 245 | int tmp1, tmp2, tmp3, length; |
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| 246 | CPXgetcols(cplexEnv(), _prob, &tmp1, &tmp2, 0, 0, 0, &length, i, i); |
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| 247 | |
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| 248 | length = -length; |
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| 249 | std::vector<int> indices(length); |
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| 250 | std::vector<double> values(length); |
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| 251 | |
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| 252 | CPXgetcols(cplexEnv(), _prob, &tmp1, &tmp2, |
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| 253 | &indices.front(), &values.front(), |
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| 254 | length, &tmp3, i, i); |
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| 255 | |
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| 256 | for (int i = 0; i < length; ++i) { |
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| 257 | *b = std::make_pair(indices[i], values[i]); |
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| 258 | ++b; |
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| 259 | } |
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| 260 | |
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| 261 | } |
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| 262 | |
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| 263 | void CplexBase::_setCoeff(int row, int col, Value value) { |
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| 264 | CPXchgcoef(cplexEnv(), _prob, row, col, value); |
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| 265 | } |
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| 266 | |
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| 267 | CplexBase::Value CplexBase::_getCoeff(int row, int col) const { |
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| 268 | CplexBase::Value value; |
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| 269 | CPXgetcoef(cplexEnv(), _prob, row, col, &value); |
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| 270 | return value; |
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| 271 | } |
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| 272 | |
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| 273 | void CplexBase::_setColLowerBound(int i, Value value) { |
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| 274 | const char s = 'L'; |
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| 275 | CPXchgbds(cplexEnv(), _prob, 1, &i, &s, &value); |
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| 276 | } |
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| 277 | |
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| 278 | CplexBase::Value CplexBase::_getColLowerBound(int i) const { |
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| 279 | CplexBase::Value res; |
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| 280 | CPXgetlb(cplexEnv(), _prob, &res, i, i); |
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| 281 | return res <= -CPX_INFBOUND ? -INF : res; |
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| 282 | } |
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| 283 | |
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| 284 | void CplexBase::_setColUpperBound(int i, Value value) |
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| 285 | { |
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| 286 | const char s = 'U'; |
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| 287 | CPXchgbds(cplexEnv(), _prob, 1, &i, &s, &value); |
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| 288 | } |
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| 289 | |
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| 290 | CplexBase::Value CplexBase::_getColUpperBound(int i) const { |
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| 291 | CplexBase::Value res; |
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| 292 | CPXgetub(cplexEnv(), _prob, &res, i, i); |
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| 293 | return res >= CPX_INFBOUND ? INF : res; |
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| 294 | } |
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| 295 | |
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| 296 | CplexBase::Value CplexBase::_getRowLowerBound(int i) const { |
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| 297 | char s; |
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| 298 | CPXgetsense(cplexEnv(), _prob, &s, i, i); |
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| 299 | CplexBase::Value res; |
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| 300 | |
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| 301 | switch (s) { |
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| 302 | case 'G': |
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| 303 | case 'R': |
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| 304 | case 'E': |
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| 305 | CPXgetrhs(cplexEnv(), _prob, &res, i, i); |
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| 306 | return res <= -CPX_INFBOUND ? -INF : res; |
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| 307 | default: |
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| 308 | return -INF; |
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| 309 | } |
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| 310 | } |
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| 311 | |
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| 312 | CplexBase::Value CplexBase::_getRowUpperBound(int i) const { |
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| 313 | char s; |
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| 314 | CPXgetsense(cplexEnv(), _prob, &s, i, i); |
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| 315 | CplexBase::Value res; |
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| 316 | |
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| 317 | switch (s) { |
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| 318 | case 'L': |
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| 319 | case 'E': |
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| 320 | CPXgetrhs(cplexEnv(), _prob, &res, i, i); |
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| 321 | return res >= CPX_INFBOUND ? INF : res; |
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| 322 | case 'R': |
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| 323 | CPXgetrhs(cplexEnv(), _prob, &res, i, i); |
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| 324 | { |
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| 325 | double rng; |
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| 326 | CPXgetrngval(cplexEnv(), _prob, &rng, i, i); |
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| 327 | res += rng; |
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| 328 | } |
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| 329 | return res >= CPX_INFBOUND ? INF : res; |
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| 330 | default: |
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| 331 | return INF; |
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| 332 | } |
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| 333 | } |
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| 334 | |
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| 335 | //This is easier to implement |
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| 336 | void CplexBase::_set_row_bounds(int i, Value lb, Value ub) { |
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| 337 | if (lb == -INF) { |
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| 338 | const char s = 'L'; |
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| 339 | CPXchgsense(cplexEnv(), _prob, 1, &i, &s); |
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| 340 | CPXchgrhs(cplexEnv(), _prob, 1, &i, &ub); |
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| 341 | } else if (ub == INF) { |
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| 342 | const char s = 'G'; |
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| 343 | CPXchgsense(cplexEnv(), _prob, 1, &i, &s); |
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| 344 | CPXchgrhs(cplexEnv(), _prob, 1, &i, &lb); |
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| 345 | } else if (lb == ub){ |
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| 346 | const char s = 'E'; |
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| 347 | CPXchgsense(cplexEnv(), _prob, 1, &i, &s); |
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| 348 | CPXchgrhs(cplexEnv(), _prob, 1, &i, &lb); |
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| 349 | } else { |
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| 350 | const char s = 'R'; |
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| 351 | CPXchgsense(cplexEnv(), _prob, 1, &i, &s); |
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| 352 | CPXchgrhs(cplexEnv(), _prob, 1, &i, &lb); |
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| 353 | double len = ub - lb; |
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| 354 | CPXchgrngval(cplexEnv(), _prob, 1, &i, &len); |
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| 355 | } |
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| 356 | } |
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| 357 | |
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| 358 | void CplexBase::_setRowLowerBound(int i, Value lb) |
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| 359 | { |
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| 360 | LEMON_ASSERT(lb != INF, "Invalid bound"); |
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| 361 | _set_row_bounds(i, lb, CplexBase::_getRowUpperBound(i)); |
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| 362 | } |
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| 363 | |
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| 364 | void CplexBase::_setRowUpperBound(int i, Value ub) |
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| 365 | { |
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| 366 | |
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| 367 | LEMON_ASSERT(ub != -INF, "Invalid bound"); |
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| 368 | _set_row_bounds(i, CplexBase::_getRowLowerBound(i), ub); |
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| 369 | } |
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| 370 | |
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| 371 | void CplexBase::_setObjCoeffs(ExprIterator b, ExprIterator e) |
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| 372 | { |
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| 373 | std::vector<int> indices; |
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| 374 | std::vector<Value> values; |
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| 375 | for(ExprIterator it=b; it!=e; ++it) { |
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| 376 | indices.push_back(it->first); |
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| 377 | values.push_back(it->second); |
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| 378 | } |
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| 379 | CPXchgobj(cplexEnv(), _prob, values.size(), |
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| 380 | &indices.front(), &values.front()); |
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| 381 | |
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| 382 | } |
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| 383 | |
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| 384 | void CplexBase::_getObjCoeffs(InsertIterator b) const |
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| 385 | { |
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| 386 | int num = CPXgetnumcols(cplexEnv(), _prob); |
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| 387 | std::vector<Value> x(num); |
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| 388 | |
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| 389 | CPXgetobj(cplexEnv(), _prob, &x.front(), 0, num - 1); |
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| 390 | for (int i = 0; i < num; ++i) { |
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| 391 | if (x[i] != 0.0) { |
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| 392 | *b = std::make_pair(i, x[i]); |
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| 393 | ++b; |
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| 394 | } |
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| 395 | } |
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| 396 | } |
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| 397 | |
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| 398 | void CplexBase::_setObjCoeff(int i, Value obj_coef) |
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| 399 | { |
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| 400 | CPXchgobj(cplexEnv(), _prob, 1, &i, &obj_coef); |
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| 401 | } |
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| 402 | |
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| 403 | CplexBase::Value CplexBase::_getObjCoeff(int i) const |
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| 404 | { |
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| 405 | Value x; |
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| 406 | CPXgetobj(cplexEnv(), _prob, &x, i, i); |
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| 407 | return x; |
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| 408 | } |
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| 409 | |
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| 410 | void CplexBase::_setSense(CplexBase::Sense sense) { |
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| 411 | switch (sense) { |
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| 412 | case MIN: |
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| 413 | CPXchgobjsen(cplexEnv(), _prob, CPX_MIN); |
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| 414 | break; |
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| 415 | case MAX: |
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| 416 | CPXchgobjsen(cplexEnv(), _prob, CPX_MAX); |
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| 417 | break; |
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| 418 | } |
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| 419 | } |
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| 420 | |
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| 421 | CplexBase::Sense CplexBase::_getSense() const { |
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| 422 | switch (CPXgetobjsen(cplexEnv(), _prob)) { |
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| 423 | case CPX_MIN: |
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| 424 | return MIN; |
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| 425 | case CPX_MAX: |
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| 426 | return MAX; |
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| 427 | default: |
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| 428 | LEMON_ASSERT(false, "Invalid sense"); |
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| 429 | return CplexBase::Sense(); |
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| 430 | } |
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| 431 | } |
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| 432 | |
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| 433 | void CplexBase::_clear() { |
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| 434 | CPXfreeprob(cplexEnv(),&_prob); |
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| 435 | int status; |
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| 436 | _prob = CPXcreateprob(cplexEnv(), &status, "Cplex problem"); |
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| 437 | rows.clear(); |
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| 438 | cols.clear(); |
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| 439 | } |
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| 440 | |
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| 441 | // CplexLp members |
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| 442 | |
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| 443 | CplexLp::CplexLp() |
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| 444 | : LpBase(), LpSolver(), CplexBase() {} |
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| 445 | |
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| 446 | CplexLp::CplexLp(const CplexEnv& env) |
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| 447 | : LpBase(), LpSolver(), CplexBase(env) {} |
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| 448 | |
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| 449 | CplexLp::CplexLp(const CplexLp& other) |
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| 450 | : LpBase(), LpSolver(), CplexBase(other) {} |
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| 451 | |
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| 452 | CplexLp::~CplexLp() {} |
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| 453 | |
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| 454 | CplexLp* CplexLp::newSolver() const { return new CplexLp; } |
|---|
| 455 | CplexLp* CplexLp::cloneSolver() const {return new CplexLp(*this); } |
|---|
| 456 | |
|---|
| 457 | const char* CplexLp::_solverName() const { return "CplexLp"; } |
|---|
| 458 | |
|---|
| 459 | void CplexLp::_clear_temporals() { |
|---|
| 460 | _col_status.clear(); |
|---|
| 461 | _row_status.clear(); |
|---|
| 462 | _primal_ray.clear(); |
|---|
| 463 | _dual_ray.clear(); |
|---|
| 464 | } |
|---|
| 465 | |
|---|
| 466 | // The routine returns zero unless an error occurred during the |
|---|
| 467 | // optimization. Examples of errors include exhausting available |
|---|
| 468 | // memory (CPXERR_NO_MEMORY) or encountering invalid data in the |
|---|
| 469 | // CPLEX problem object (CPXERR_NO_PROBLEM). Exceeding a |
|---|
| 470 | // user-specified CPLEX limit, or proving the model infeasible or |
|---|
| 471 | // unbounded, are not considered errors. Note that a zero return |
|---|
| 472 | // value does not necessarily mean that a solution exists. Use query |
|---|
| 473 | // routines CPXsolninfo, CPXgetstat, and CPXsolution to obtain |
|---|
| 474 | // further information about the status of the optimization. |
|---|
| 475 | CplexLp::SolveExitStatus CplexLp::convertStatus(int status) { |
|---|
| 476 | #if CPX_VERSION >= 800 |
|---|
| 477 | if (status == 0) { |
|---|
| 478 | switch (CPXgetstat(cplexEnv(), _prob)) { |
|---|
| 479 | case CPX_STAT_OPTIMAL: |
|---|
| 480 | case CPX_STAT_INFEASIBLE: |
|---|
| 481 | case CPX_STAT_UNBOUNDED: |
|---|
| 482 | return SOLVED; |
|---|
| 483 | default: |
|---|
| 484 | return UNSOLVED; |
|---|
| 485 | } |
|---|
| 486 | } else { |
|---|
| 487 | return UNSOLVED; |
|---|
| 488 | } |
|---|
| 489 | #else |
|---|
| 490 | if (status == 0) { |
|---|
| 491 | //We want to exclude some cases |
|---|
| 492 | switch (CPXgetstat(cplexEnv(), _prob)) { |
|---|
| 493 | case CPX_OBJ_LIM: |
|---|
| 494 | case CPX_IT_LIM_FEAS: |
|---|
| 495 | case CPX_IT_LIM_INFEAS: |
|---|
| 496 | case CPX_TIME_LIM_FEAS: |
|---|
| 497 | case CPX_TIME_LIM_INFEAS: |
|---|
| 498 | return UNSOLVED; |
|---|
| 499 | default: |
|---|
| 500 | return SOLVED; |
|---|
| 501 | } |
|---|
| 502 | } else { |
|---|
| 503 | return UNSOLVED; |
|---|
| 504 | } |
|---|
| 505 | #endif |
|---|
| 506 | } |
|---|
| 507 | |
|---|
| 508 | CplexLp::SolveExitStatus CplexLp::_solve() { |
|---|
| 509 | _clear_temporals(); |
|---|
| 510 | return convertStatus(CPXlpopt(cplexEnv(), _prob)); |
|---|
| 511 | } |
|---|
| 512 | |
|---|
| 513 | CplexLp::SolveExitStatus CplexLp::solvePrimal() { |
|---|
| 514 | _clear_temporals(); |
|---|
| 515 | return convertStatus(CPXprimopt(cplexEnv(), _prob)); |
|---|
| 516 | } |
|---|
| 517 | |
|---|
| 518 | CplexLp::SolveExitStatus CplexLp::solveDual() { |
|---|
| 519 | _clear_temporals(); |
|---|
| 520 | return convertStatus(CPXdualopt(cplexEnv(), _prob)); |
|---|
| 521 | } |
|---|
| 522 | |
|---|
| 523 | CplexLp::SolveExitStatus CplexLp::solveBarrier() { |
|---|
| 524 | _clear_temporals(); |
|---|
| 525 | return convertStatus(CPXbaropt(cplexEnv(), _prob)); |
|---|
| 526 | } |
|---|
| 527 | |
|---|
| 528 | CplexLp::Value CplexLp::_getPrimal(int i) const { |
|---|
| 529 | Value x; |
|---|
| 530 | CPXgetx(cplexEnv(), _prob, &x, i, i); |
|---|
| 531 | return x; |
|---|
| 532 | } |
|---|
| 533 | |
|---|
| 534 | CplexLp::Value CplexLp::_getDual(int i) const { |
|---|
| 535 | Value y; |
|---|
| 536 | CPXgetpi(cplexEnv(), _prob, &y, i, i); |
|---|
| 537 | return y; |
|---|
| 538 | } |
|---|
| 539 | |
|---|
| 540 | CplexLp::Value CplexLp::_getPrimalValue() const { |
|---|
| 541 | Value objval; |
|---|
| 542 | CPXgetobjval(cplexEnv(), _prob, &objval); |
|---|
| 543 | return objval; |
|---|
| 544 | } |
|---|
| 545 | |
|---|
| 546 | CplexLp::VarStatus CplexLp::_getColStatus(int i) const { |
|---|
| 547 | if (_col_status.empty()) { |
|---|
| 548 | _col_status.resize(CPXgetnumcols(cplexEnv(), _prob)); |
|---|
| 549 | CPXgetbase(cplexEnv(), _prob, &_col_status.front(), 0); |
|---|
| 550 | } |
|---|
| 551 | switch (_col_status[i]) { |
|---|
| 552 | case CPX_BASIC: |
|---|
| 553 | return BASIC; |
|---|
| 554 | case CPX_FREE_SUPER: |
|---|
| 555 | return FREE; |
|---|
| 556 | case CPX_AT_LOWER: |
|---|
| 557 | return LOWER; |
|---|
| 558 | case CPX_AT_UPPER: |
|---|
| 559 | return UPPER; |
|---|
| 560 | default: |
|---|
| 561 | LEMON_ASSERT(false, "Wrong column status"); |
|---|
| 562 | return CplexLp::VarStatus(); |
|---|
| 563 | } |
|---|
| 564 | } |
|---|
| 565 | |
|---|
| 566 | CplexLp::VarStatus CplexLp::_getRowStatus(int i) const { |
|---|
| 567 | if (_row_status.empty()) { |
|---|
| 568 | _row_status.resize(CPXgetnumrows(cplexEnv(), _prob)); |
|---|
| 569 | CPXgetbase(cplexEnv(), _prob, 0, &_row_status.front()); |
|---|
| 570 | } |
|---|
| 571 | switch (_row_status[i]) { |
|---|
| 572 | case CPX_BASIC: |
|---|
| 573 | return BASIC; |
|---|
| 574 | case CPX_AT_LOWER: |
|---|
| 575 | { |
|---|
| 576 | char s; |
|---|
| 577 | CPXgetsense(cplexEnv(), _prob, &s, i, i); |
|---|
| 578 | return s != 'L' ? LOWER : UPPER; |
|---|
| 579 | } |
|---|
| 580 | case CPX_AT_UPPER: |
|---|
| 581 | return UPPER; |
|---|
| 582 | default: |
|---|
| 583 | LEMON_ASSERT(false, "Wrong row status"); |
|---|
| 584 | return CplexLp::VarStatus(); |
|---|
| 585 | } |
|---|
| 586 | } |
|---|
| 587 | |
|---|
| 588 | CplexLp::Value CplexLp::_getPrimalRay(int i) const { |
|---|
| 589 | if (_primal_ray.empty()) { |
|---|
| 590 | _primal_ray.resize(CPXgetnumcols(cplexEnv(), _prob)); |
|---|
| 591 | CPXgetray(cplexEnv(), _prob, &_primal_ray.front()); |
|---|
| 592 | } |
|---|
| 593 | return _primal_ray[i]; |
|---|
| 594 | } |
|---|
| 595 | |
|---|
| 596 | CplexLp::Value CplexLp::_getDualRay(int i) const { |
|---|
| 597 | if (_dual_ray.empty()) { |
|---|
| 598 | |
|---|
| 599 | } |
|---|
| 600 | return _dual_ray[i]; |
|---|
| 601 | } |
|---|
| 602 | |
|---|
| 603 | //7.5-os cplex statusai (Vigyazat: a 9.0-asei masok!) |
|---|
| 604 | // This table lists the statuses, returned by the CPXgetstat() |
|---|
| 605 | // routine, for solutions to LP problems or mixed integer problems. If |
|---|
| 606 | // no solution exists, the return value is zero. |
|---|
| 607 | |
|---|
| 608 | // For Simplex, Barrier |
|---|
| 609 | // 1 CPX_OPTIMAL |
|---|
| 610 | // Optimal solution found |
|---|
| 611 | // 2 CPX_INFEASIBLE |
|---|
| 612 | // Problem infeasible |
|---|
| 613 | // 3 CPX_UNBOUNDED |
|---|
| 614 | // Problem unbounded |
|---|
| 615 | // 4 CPX_OBJ_LIM |
|---|
| 616 | // Objective limit exceeded in Phase II |
|---|
| 617 | // 5 CPX_IT_LIM_FEAS |
|---|
| 618 | // Iteration limit exceeded in Phase II |
|---|
| 619 | // 6 CPX_IT_LIM_INFEAS |
|---|
| 620 | // Iteration limit exceeded in Phase I |
|---|
| 621 | // 7 CPX_TIME_LIM_FEAS |
|---|
| 622 | // Time limit exceeded in Phase II |
|---|
| 623 | // 8 CPX_TIME_LIM_INFEAS |
|---|
| 624 | // Time limit exceeded in Phase I |
|---|
| 625 | // 9 CPX_NUM_BEST_FEAS |
|---|
| 626 | // Problem non-optimal, singularities in Phase II |
|---|
| 627 | // 10 CPX_NUM_BEST_INFEAS |
|---|
| 628 | // Problem non-optimal, singularities in Phase I |
|---|
| 629 | // 11 CPX_OPTIMAL_INFEAS |
|---|
| 630 | // Optimal solution found, unscaled infeasibilities |
|---|
| 631 | // 12 CPX_ABORT_FEAS |
|---|
| 632 | // Aborted in Phase II |
|---|
| 633 | // 13 CPX_ABORT_INFEAS |
|---|
| 634 | // Aborted in Phase I |
|---|
| 635 | // 14 CPX_ABORT_DUAL_INFEAS |
|---|
| 636 | // Aborted in barrier, dual infeasible |
|---|
| 637 | // 15 CPX_ABORT_PRIM_INFEAS |
|---|
| 638 | // Aborted in barrier, primal infeasible |
|---|
| 639 | // 16 CPX_ABORT_PRIM_DUAL_INFEAS |
|---|
| 640 | // Aborted in barrier, primal and dual infeasible |
|---|
| 641 | // 17 CPX_ABORT_PRIM_DUAL_FEAS |
|---|
| 642 | // Aborted in barrier, primal and dual feasible |
|---|
| 643 | // 18 CPX_ABORT_CROSSOVER |
|---|
| 644 | // Aborted in crossover |
|---|
| 645 | // 19 CPX_INForUNBD |
|---|
| 646 | // Infeasible or unbounded |
|---|
| 647 | // 20 CPX_PIVOT |
|---|
| 648 | // User pivot used |
|---|
| 649 | // |
|---|
| 650 | // Ezeket hova tegyem: |
|---|
| 651 | // ??case CPX_ABORT_DUAL_INFEAS |
|---|
| 652 | // ??case CPX_ABORT_CROSSOVER |
|---|
| 653 | // ??case CPX_INForUNBD |
|---|
| 654 | // ??case CPX_PIVOT |
|---|
| 655 | |
|---|
| 656 | //Some more interesting stuff: |
|---|
| 657 | |
|---|
| 658 | // CPX_PARAM_PROBMETHOD 1062 int LPMETHOD |
|---|
| 659 | // 0 Automatic |
|---|
| 660 | // 1 Primal Simplex |
|---|
| 661 | // 2 Dual Simplex |
|---|
| 662 | // 3 Network Simplex |
|---|
| 663 | // 4 Standard Barrier |
|---|
| 664 | // Default: 0 |
|---|
| 665 | // Description: Method for linear optimization. |
|---|
| 666 | // Determines which algorithm is used when CPXlpopt() (or "optimize" |
|---|
| 667 | // in the Interactive Optimizer) is called. Currently the behavior of |
|---|
| 668 | // the "Automatic" setting is that CPLEX simply invokes the dual |
|---|
| 669 | // simplex method, but this capability may be expanded in the future |
|---|
| 670 | // so that CPLEX chooses the method based on problem characteristics |
|---|
| 671 | #if CPX_VERSION < 900 |
|---|
| 672 | void statusSwitch(CPXENVptr cplexEnv(),int& stat){ |
|---|
| 673 | int lpmethod; |
|---|
| 674 | CPXgetintparam (cplexEnv(),CPX_PARAM_PROBMETHOD,&lpmethod); |
|---|
| 675 | if (lpmethod==2){ |
|---|
| 676 | if (stat==CPX_UNBOUNDED){ |
|---|
| 677 | stat=CPX_INFEASIBLE; |
|---|
| 678 | } |
|---|
| 679 | else{ |
|---|
| 680 | if (stat==CPX_INFEASIBLE) |
|---|
| 681 | stat=CPX_UNBOUNDED; |
|---|
| 682 | } |
|---|
| 683 | } |
|---|
| 684 | } |
|---|
| 685 | #else |
|---|
| 686 | void statusSwitch(CPXENVptr,int&){} |
|---|
| 687 | #endif |
|---|
| 688 | |
|---|
| 689 | CplexLp::ProblemType CplexLp::_getPrimalType() const { |
|---|
| 690 | // Unboundedness not treated well: the following is from cplex 9.0 doc |
|---|
| 691 | // About Unboundedness |
|---|
| 692 | |
|---|
| 693 | // The treatment of models that are unbounded involves a few |
|---|
| 694 | // subtleties. Specifically, a declaration of unboundedness means that |
|---|
| 695 | // ILOG CPLEX has determined that the model has an unbounded |
|---|
| 696 | // ray. Given any feasible solution x with objective z, a multiple of |
|---|
| 697 | // the unbounded ray can be added to x to give a feasible solution |
|---|
| 698 | // with objective z-1 (or z+1 for maximization models). Thus, if a |
|---|
| 699 | // feasible solution exists, then the optimal objective is |
|---|
| 700 | // unbounded. Note that ILOG CPLEX has not necessarily concluded that |
|---|
| 701 | // a feasible solution exists. Users can call the routine CPXsolninfo |
|---|
| 702 | // to determine whether ILOG CPLEX has also concluded that the model |
|---|
| 703 | // has a feasible solution. |
|---|
| 704 | |
|---|
| 705 | int stat = CPXgetstat(cplexEnv(), _prob); |
|---|
| 706 | #if CPX_VERSION >= 800 |
|---|
| 707 | switch (stat) |
|---|
| 708 | { |
|---|
| 709 | case CPX_STAT_OPTIMAL: |
|---|
| 710 | return OPTIMAL; |
|---|
| 711 | case CPX_STAT_UNBOUNDED: |
|---|
| 712 | return UNBOUNDED; |
|---|
| 713 | case CPX_STAT_INFEASIBLE: |
|---|
| 714 | return INFEASIBLE; |
|---|
| 715 | default: |
|---|
| 716 | return UNDEFINED; |
|---|
| 717 | } |
|---|
| 718 | #else |
|---|
| 719 | statusSwitch(cplexEnv(),stat); |
|---|
| 720 | //CPXgetstat(cplexEnv(), _prob); |
|---|
| 721 | //printf("A primal status: %d, CPX_OPTIMAL=%d \n",stat,CPX_OPTIMAL); |
|---|
| 722 | switch (stat) { |
|---|
| 723 | case 0: |
|---|
| 724 | return UNDEFINED; //Undefined |
|---|
| 725 | case CPX_OPTIMAL://Optimal |
|---|
| 726 | return OPTIMAL; |
|---|
| 727 | case CPX_UNBOUNDED://Unbounded |
|---|
| 728 | return INFEASIBLE;//In case of dual simplex |
|---|
| 729 | //return UNBOUNDED; |
|---|
| 730 | case CPX_INFEASIBLE://Infeasible |
|---|
| 731 | // case CPX_IT_LIM_INFEAS: |
|---|
| 732 | // case CPX_TIME_LIM_INFEAS: |
|---|
| 733 | // case CPX_NUM_BEST_INFEAS: |
|---|
| 734 | // case CPX_OPTIMAL_INFEAS: |
|---|
| 735 | // case CPX_ABORT_INFEAS: |
|---|
| 736 | // case CPX_ABORT_PRIM_INFEAS: |
|---|
| 737 | // case CPX_ABORT_PRIM_DUAL_INFEAS: |
|---|
| 738 | return UNBOUNDED;//In case of dual simplex |
|---|
| 739 | //return INFEASIBLE; |
|---|
| 740 | // case CPX_OBJ_LIM: |
|---|
| 741 | // case CPX_IT_LIM_FEAS: |
|---|
| 742 | // case CPX_TIME_LIM_FEAS: |
|---|
| 743 | // case CPX_NUM_BEST_FEAS: |
|---|
| 744 | // case CPX_ABORT_FEAS: |
|---|
| 745 | // case CPX_ABORT_PRIM_DUAL_FEAS: |
|---|
| 746 | // return FEASIBLE; |
|---|
| 747 | default: |
|---|
| 748 | return UNDEFINED; //Everything else comes here |
|---|
| 749 | //FIXME error |
|---|
| 750 | } |
|---|
| 751 | #endif |
|---|
| 752 | } |
|---|
| 753 | |
|---|
| 754 | //9.0-as cplex verzio statusai |
|---|
| 755 | // CPX_STAT_ABORT_DUAL_OBJ_LIM |
|---|
| 756 | // CPX_STAT_ABORT_IT_LIM |
|---|
| 757 | // CPX_STAT_ABORT_OBJ_LIM |
|---|
| 758 | // CPX_STAT_ABORT_PRIM_OBJ_LIM |
|---|
| 759 | // CPX_STAT_ABORT_TIME_LIM |
|---|
| 760 | // CPX_STAT_ABORT_USER |
|---|
| 761 | // CPX_STAT_FEASIBLE_RELAXED |
|---|
| 762 | // CPX_STAT_INFEASIBLE |
|---|
| 763 | // CPX_STAT_INForUNBD |
|---|
| 764 | // CPX_STAT_NUM_BEST |
|---|
| 765 | // CPX_STAT_OPTIMAL |
|---|
| 766 | // CPX_STAT_OPTIMAL_FACE_UNBOUNDED |
|---|
| 767 | // CPX_STAT_OPTIMAL_INFEAS |
|---|
| 768 | // CPX_STAT_OPTIMAL_RELAXED |
|---|
| 769 | // CPX_STAT_UNBOUNDED |
|---|
| 770 | |
|---|
| 771 | CplexLp::ProblemType CplexLp::_getDualType() const { |
|---|
| 772 | int stat = CPXgetstat(cplexEnv(), _prob); |
|---|
| 773 | #if CPX_VERSION >= 800 |
|---|
| 774 | switch (stat) { |
|---|
| 775 | case CPX_STAT_OPTIMAL: |
|---|
| 776 | return OPTIMAL; |
|---|
| 777 | case CPX_STAT_UNBOUNDED: |
|---|
| 778 | return INFEASIBLE; |
|---|
| 779 | default: |
|---|
| 780 | return UNDEFINED; |
|---|
| 781 | } |
|---|
| 782 | #else |
|---|
| 783 | statusSwitch(cplexEnv(),stat); |
|---|
| 784 | switch (stat) { |
|---|
| 785 | case 0: |
|---|
| 786 | return UNDEFINED; //Undefined |
|---|
| 787 | case CPX_OPTIMAL://Optimal |
|---|
| 788 | return OPTIMAL; |
|---|
| 789 | case CPX_UNBOUNDED: |
|---|
| 790 | return INFEASIBLE; |
|---|
| 791 | default: |
|---|
| 792 | return UNDEFINED; //Everything else comes here |
|---|
| 793 | //FIXME error |
|---|
| 794 | } |
|---|
| 795 | #endif |
|---|
| 796 | } |
|---|
| 797 | |
|---|
| 798 | // CplexMip members |
|---|
| 799 | |
|---|
| 800 | CplexMip::CplexMip() |
|---|
| 801 | : LpBase(), MipSolver(), CplexBase() { |
|---|
| 802 | |
|---|
| 803 | #if CPX_VERSION < 800 |
|---|
| 804 | CPXchgprobtype(cplexEnv(), _prob, CPXPROB_MIP); |
|---|
| 805 | #else |
|---|
| 806 | CPXchgprobtype(cplexEnv(), _prob, CPXPROB_MILP); |
|---|
| 807 | #endif |
|---|
| 808 | } |
|---|
| 809 | |
|---|
| 810 | CplexMip::CplexMip(const CplexEnv& env) |
|---|
| 811 | : LpBase(), MipSolver(), CplexBase(env) { |
|---|
| 812 | |
|---|
| 813 | #if CPX_VERSION < 800 |
|---|
| 814 | CPXchgprobtype(cplexEnv(), _prob, CPXPROB_MIP); |
|---|
| 815 | #else |
|---|
| 816 | CPXchgprobtype(cplexEnv(), _prob, CPXPROB_MILP); |
|---|
| 817 | #endif |
|---|
| 818 | |
|---|
| 819 | } |
|---|
| 820 | |
|---|
| 821 | CplexMip::CplexMip(const CplexMip& other) |
|---|
| 822 | : LpBase(), MipSolver(), CplexBase(other) {} |
|---|
| 823 | |
|---|
| 824 | CplexMip::~CplexMip() {} |
|---|
| 825 | |
|---|
| 826 | CplexMip* CplexMip::newSolver() const { return new CplexMip; } |
|---|
| 827 | CplexMip* CplexMip::cloneSolver() const {return new CplexMip(*this); } |
|---|
| 828 | |
|---|
| 829 | const char* CplexMip::_solverName() const { return "CplexMip"; } |
|---|
| 830 | |
|---|
| 831 | void CplexMip::_setColType(int i, CplexMip::ColTypes col_type) { |
|---|
| 832 | |
|---|
| 833 | // Note If a variable is to be changed to binary, a call to CPXchgbds |
|---|
| 834 | // should also be made to change the bounds to 0 and 1. |
|---|
| 835 | |
|---|
| 836 | switch (col_type){ |
|---|
| 837 | case INTEGER: { |
|---|
| 838 | const char t = 'I'; |
|---|
| 839 | CPXchgctype (cplexEnv(), _prob, 1, &i, &t); |
|---|
| 840 | } break; |
|---|
| 841 | case REAL: { |
|---|
| 842 | const char t = 'C'; |
|---|
| 843 | CPXchgctype (cplexEnv(), _prob, 1, &i, &t); |
|---|
| 844 | } break; |
|---|
| 845 | default: |
|---|
| 846 | break; |
|---|
| 847 | } |
|---|
| 848 | } |
|---|
| 849 | |
|---|
| 850 | CplexMip::ColTypes CplexMip::_getColType(int i) const { |
|---|
| 851 | char t; |
|---|
| 852 | CPXgetctype (cplexEnv(), _prob, &t, i, i); |
|---|
| 853 | switch (t) { |
|---|
| 854 | case 'I': |
|---|
| 855 | return INTEGER; |
|---|
| 856 | case 'C': |
|---|
| 857 | return REAL; |
|---|
| 858 | default: |
|---|
| 859 | LEMON_ASSERT(false, "Invalid column type"); |
|---|
| 860 | return ColTypes(); |
|---|
| 861 | } |
|---|
| 862 | |
|---|
| 863 | } |
|---|
| 864 | |
|---|
| 865 | CplexMip::SolveExitStatus CplexMip::_solve() { |
|---|
| 866 | int status; |
|---|
| 867 | status = CPXmipopt (cplexEnv(), _prob); |
|---|
| 868 | if (status==0) |
|---|
| 869 | return SOLVED; |
|---|
| 870 | else |
|---|
| 871 | return UNSOLVED; |
|---|
| 872 | |
|---|
| 873 | } |
|---|
| 874 | |
|---|
| 875 | |
|---|
| 876 | CplexMip::ProblemType CplexMip::_getType() const { |
|---|
| 877 | |
|---|
| 878 | int stat = CPXgetstat(cplexEnv(), _prob); |
|---|
| 879 | |
|---|
| 880 | //Fortunately, MIP statuses did not change for cplex 8.0 |
|---|
| 881 | switch (stat) { |
|---|
| 882 | case CPXMIP_OPTIMAL: |
|---|
| 883 | // Optimal integer solution has been found. |
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| 884 | case CPXMIP_OPTIMAL_TOL: |
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| 885 | // Optimal soluton with the tolerance defined by epgap or epagap has |
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| 886 | // been found. |
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| 887 | return OPTIMAL; |
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| 888 | //This also exists in later issues |
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| 889 | // case CPXMIP_UNBOUNDED: |
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| 890 | //return UNBOUNDED; |
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| 891 | case CPXMIP_INFEASIBLE: |
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| 892 | return INFEASIBLE; |
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| 893 | default: |
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| 894 | return UNDEFINED; |
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| 895 | } |
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| 896 | //Unboundedness not treated well: the following is from cplex 9.0 doc |
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| 897 | // About Unboundedness |
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| 898 | |
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| 899 | // The treatment of models that are unbounded involves a few |
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| 900 | // subtleties. Specifically, a declaration of unboundedness means that |
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| 901 | // ILOG CPLEX has determined that the model has an unbounded |
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| 902 | // ray. Given any feasible solution x with objective z, a multiple of |
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| 903 | // the unbounded ray can be added to x to give a feasible solution |
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| 904 | // with objective z-1 (or z+1 for maximization models). Thus, if a |
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| 905 | // feasible solution exists, then the optimal objective is |
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| 906 | // unbounded. Note that ILOG CPLEX has not necessarily concluded that |
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| 907 | // a feasible solution exists. Users can call the routine CPXsolninfo |
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| 908 | // to determine whether ILOG CPLEX has also concluded that the model |
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| 909 | // has a feasible solution. |
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| 910 | } |
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| 911 | |
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| 912 | CplexMip::Value CplexMip::_getSol(int i) const { |
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| 913 | Value x; |
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| 914 | CPXgetmipx(cplexEnv(), _prob, &x, i, i); |
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| 915 | return x; |
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| 916 | } |
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| 917 | |
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| 918 | CplexMip::Value CplexMip::_getSolValue() const { |
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| 919 | Value objval; |
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| 920 | CPXgetmipobjval(cplexEnv(), _prob, &objval); |
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| 921 | return objval; |
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| 922 | } |
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| 923 | |
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| 924 | } //namespace lemon |
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| 925 | |
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