lemon/cplex.cc
author Alpar Juttner <alpar@cs.elte.hu>
Tue, 24 Feb 2009 06:52:17 +0000
changeset 524 97674155c135
parent 461 08d495d48089
child 528 9db62975c32b
permissions -rw-r--r--
Merge
     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 <iostream>
    20 #include <vector>
    21 #include <cstring>
    22 
    23 #include <lemon/cplex.h>
    24 
    25 extern "C" {
    26 #include <ilcplex/cplex.h>
    27 }
    28 
    29 
    30 ///\file
    31 ///\brief Implementation of the LEMON-CPLEX lp solver interface.
    32 namespace lemon {
    33 
    34   CplexEnv::LicenseError::LicenseError(int status) {
    35     if (!CPXgeterrorstring(0, status, _message)) {
    36       std::strcpy(_message, "Cplex unknown error");
    37     }
    38   }
    39 
    40   CplexEnv::CplexEnv() {
    41     int status;
    42     _cnt = new int;
    43     _env = CPXopenCPLEX(&status);
    44     if (_env == 0) {
    45       delete _cnt;
    46       _cnt = 0;
    47       throw LicenseError(status);
    48     }
    49   }
    50 
    51   CplexEnv::CplexEnv(const CplexEnv& other) {
    52     _env = other._env;
    53     _cnt = other._cnt;
    54     ++(*_cnt);
    55   }
    56 
    57   CplexEnv& CplexEnv::operator=(const CplexEnv& other) {
    58     _env = other._env;
    59     _cnt = other._cnt;
    60     ++(*_cnt);
    61     return *this;
    62   }
    63 
    64   CplexEnv::~CplexEnv() {
    65     --(*_cnt);
    66     if (*_cnt == 0) {
    67       delete _cnt;
    68       CPXcloseCPLEX(&_env);
    69     }
    70   }
    71 
    72   CplexBase::CplexBase() : LpBase() {
    73     int status;
    74     _prob = CPXcreateprob(cplexEnv(), &status, "Cplex problem");
    75   }
    76 
    77   CplexBase::CplexBase(const CplexEnv& env)
    78     : LpBase(), _env(env) {
    79     int status;
    80     _prob = CPXcreateprob(cplexEnv(), &status, "Cplex problem");
    81   }
    82 
    83   CplexBase::CplexBase(const CplexBase& cplex)
    84     : LpBase() {
    85     int status;
    86     _prob = CPXcloneprob(cplexEnv(), cplex._prob, &status);
    87     rows = cplex.rows;
    88     cols = cplex.cols;
    89   }
    90 
    91   CplexBase::~CplexBase() {
    92     CPXfreeprob(cplexEnv(),&_prob);
    93   }
    94 
    95   int CplexBase::_addCol() {
    96     int i = CPXgetnumcols(cplexEnv(), _prob);
    97     double lb = -INF, ub = INF;
    98     CPXnewcols(cplexEnv(), _prob, 1, 0, &lb, &ub, 0, 0);
    99     return i;
   100   }
   101 
   102 
   103   int CplexBase::_addRow() {
   104     int i = CPXgetnumrows(cplexEnv(), _prob);
   105     const double ub = INF;
   106     const char s = 'L';
   107     CPXnewrows(cplexEnv(), _prob, 1, &ub, &s, 0, 0);
   108     return i;
   109   }
   110 
   111 
   112   void CplexBase::_eraseCol(int i) {
   113     CPXdelcols(cplexEnv(), _prob, i, i);
   114   }
   115 
   116   void CplexBase::_eraseRow(int i) {
   117     CPXdelrows(cplexEnv(), _prob, i, i);
   118   }
   119 
   120   void CplexBase::_eraseColId(int i) {
   121     cols.eraseIndex(i);
   122     cols.shiftIndices(i);
   123   }
   124   void CplexBase::_eraseRowId(int i) {
   125     rows.eraseIndex(i);
   126     rows.shiftIndices(i);
   127   }
   128 
   129   void CplexBase::_getColName(int col, std::string &name) const {
   130     int size;
   131     CPXgetcolname(cplexEnv(), _prob, 0, 0, 0, &size, col, col);
   132     if (size == 0) {
   133       name.clear();
   134       return;
   135     }
   136 
   137     size *= -1;
   138     std::vector<char> buf(size);
   139     char *cname;
   140     int tmp;
   141     CPXgetcolname(cplexEnv(), _prob, &cname, &buf.front(), size,
   142                   &tmp, col, col);
   143     name = cname;
   144   }
   145 
   146   void CplexBase::_setColName(int col, const std::string &name) {
   147     char *cname;
   148     cname = const_cast<char*>(name.c_str());
   149     CPXchgcolname(cplexEnv(), _prob, 1, &col, &cname);
   150   }
   151 
   152   int CplexBase::_colByName(const std::string& name) const {
   153     int index;
   154     if (CPXgetcolindex(cplexEnv(), _prob,
   155                        const_cast<char*>(name.c_str()), &index) == 0) {
   156       return index;
   157     }
   158     return -1;
   159   }
   160 
   161   void CplexBase::_getRowName(int row, std::string &name) const {
   162     int size;
   163     CPXgetrowname(cplexEnv(), _prob, 0, 0, 0, &size, row, row);
   164     if (size == 0) {
   165       name.clear();
   166       return;
   167     }
   168 
   169     size *= -1;
   170     std::vector<char> buf(size);
   171     char *cname;
   172     int tmp;
   173     CPXgetrowname(cplexEnv(), _prob, &cname, &buf.front(), size,
   174                   &tmp, row, row);
   175     name = cname;
   176   }
   177 
   178   void CplexBase::_setRowName(int row, const std::string &name) {
   179     char *cname;
   180     cname = const_cast<char*>(name.c_str());
   181     CPXchgrowname(cplexEnv(), _prob, 1, &row, &cname);
   182   }
   183 
   184   int CplexBase::_rowByName(const std::string& name) const {
   185     int index;
   186     if (CPXgetrowindex(cplexEnv(), _prob,
   187                        const_cast<char*>(name.c_str()), &index) == 0) {
   188       return index;
   189     }
   190     return -1;
   191   }
   192 
   193   void CplexBase::_setRowCoeffs(int i, ExprIterator b,
   194                                       ExprIterator e)
   195   {
   196     std::vector<int> indices;
   197     std::vector<int> rowlist;
   198     std::vector<Value> values;
   199 
   200     for(ExprIterator it=b; it!=e; ++it) {
   201       indices.push_back(it->first);
   202       values.push_back(it->second);
   203       rowlist.push_back(i);
   204     }
   205 
   206     CPXchgcoeflist(cplexEnv(), _prob, values.size(),
   207                    &rowlist.front(), &indices.front(), &values.front());
   208   }
   209 
   210   void CplexBase::_getRowCoeffs(int i, InsertIterator b) const {
   211     int tmp1, tmp2, tmp3, length;
   212     CPXgetrows(cplexEnv(), _prob, &tmp1, &tmp2, 0, 0, 0, &length, i, i);
   213 
   214     length = -length;
   215     std::vector<int> indices(length);
   216     std::vector<double> values(length);
   217 
   218     CPXgetrows(cplexEnv(), _prob, &tmp1, &tmp2,
   219                &indices.front(), &values.front(),
   220                length, &tmp3, i, i);
   221 
   222     for (int i = 0; i < length; ++i) {
   223       *b = std::make_pair(indices[i], values[i]);
   224       ++b;
   225     }
   226   }
   227 
   228   void CplexBase::_setColCoeffs(int i, ExprIterator b, ExprIterator e) {
   229     std::vector<int> indices;
   230     std::vector<int> collist;
   231     std::vector<Value> values;
   232 
   233     for(ExprIterator it=b; it!=e; ++it) {
   234       indices.push_back(it->first);
   235       values.push_back(it->second);
   236       collist.push_back(i);
   237     }
   238 
   239     CPXchgcoeflist(cplexEnv(), _prob, values.size(),
   240                    &indices.front(), &collist.front(), &values.front());
   241   }
   242 
   243   void CplexBase::_getColCoeffs(int i, InsertIterator b) const {
   244 
   245     int tmp1, tmp2, tmp3, length;
   246     CPXgetcols(cplexEnv(), _prob, &tmp1, &tmp2, 0, 0, 0, &length, i, i);
   247 
   248     length = -length;
   249     std::vector<int> indices(length);
   250     std::vector<double> values(length);
   251 
   252     CPXgetcols(cplexEnv(), _prob, &tmp1, &tmp2,
   253                &indices.front(), &values.front(),
   254                length, &tmp3, i, i);
   255 
   256     for (int i = 0; i < length; ++i) {
   257       *b = std::make_pair(indices[i], values[i]);
   258       ++b;
   259     }
   260 
   261   }
   262 
   263   void CplexBase::_setCoeff(int row, int col, Value value) {
   264     CPXchgcoef(cplexEnv(), _prob, row, col, value);
   265   }
   266 
   267   CplexBase::Value CplexBase::_getCoeff(int row, int col) const {
   268     CplexBase::Value value;
   269     CPXgetcoef(cplexEnv(), _prob, row, col, &value);
   270     return value;
   271   }
   272 
   273   void CplexBase::_setColLowerBound(int i, Value value) {
   274     const char s = 'L';
   275     CPXchgbds(cplexEnv(), _prob, 1, &i, &s, &value);
   276   }
   277 
   278   CplexBase::Value CplexBase::_getColLowerBound(int i) const {
   279     CplexBase::Value res;
   280     CPXgetlb(cplexEnv(), _prob, &res, i, i);
   281     return res <= -CPX_INFBOUND ? -INF : res;
   282   }
   283 
   284   void CplexBase::_setColUpperBound(int i, Value value)
   285   {
   286     const char s = 'U';
   287     CPXchgbds(cplexEnv(), _prob, 1, &i, &s, &value);
   288   }
   289 
   290   CplexBase::Value CplexBase::_getColUpperBound(int i) const {
   291     CplexBase::Value res;
   292     CPXgetub(cplexEnv(), _prob, &res, i, i);
   293     return res >= CPX_INFBOUND ? INF : res;
   294   }
   295 
   296   CplexBase::Value CplexBase::_getRowLowerBound(int i) const {
   297     char s;
   298     CPXgetsense(cplexEnv(), _prob, &s, i, i);
   299     CplexBase::Value res;
   300 
   301     switch (s) {
   302     case 'G':
   303     case 'R':
   304     case 'E':
   305       CPXgetrhs(cplexEnv(), _prob, &res, i, i);
   306       return res <= -CPX_INFBOUND ? -INF : res;
   307     default:
   308       return -INF;
   309     }
   310   }
   311 
   312   CplexBase::Value CplexBase::_getRowUpperBound(int i) const {
   313     char s;
   314     CPXgetsense(cplexEnv(), _prob, &s, i, i);
   315     CplexBase::Value res;
   316 
   317     switch (s) {
   318     case 'L':
   319     case 'E':
   320       CPXgetrhs(cplexEnv(), _prob, &res, i, i);
   321       return res >= CPX_INFBOUND ? INF : res;
   322     case 'R':
   323       CPXgetrhs(cplexEnv(), _prob, &res, i, i);
   324       {
   325         double rng;
   326         CPXgetrngval(cplexEnv(), _prob, &rng, i, i);
   327         res += rng;
   328       }
   329       return res >= CPX_INFBOUND ? INF : res;
   330     default:
   331       return INF;
   332     }
   333   }
   334 
   335   //This is easier to implement
   336   void CplexBase::_set_row_bounds(int i, Value lb, Value ub) {
   337     if (lb == -INF) {
   338       const char s = 'L';
   339       CPXchgsense(cplexEnv(), _prob, 1, &i, &s);
   340       CPXchgrhs(cplexEnv(), _prob, 1, &i, &ub);
   341     } else if (ub == INF) {
   342       const char s = 'G';
   343       CPXchgsense(cplexEnv(), _prob, 1, &i, &s);
   344       CPXchgrhs(cplexEnv(), _prob, 1, &i, &lb);
   345     } else if (lb == ub){
   346       const char s = 'E';
   347       CPXchgsense(cplexEnv(), _prob, 1, &i, &s);
   348       CPXchgrhs(cplexEnv(), _prob, 1, &i, &lb);
   349     } else {
   350       const char s = 'R';
   351       CPXchgsense(cplexEnv(), _prob, 1, &i, &s);
   352       CPXchgrhs(cplexEnv(), _prob, 1, &i, &lb);
   353       double len = ub - lb;
   354       CPXchgrngval(cplexEnv(), _prob, 1, &i, &len);
   355     }
   356   }
   357 
   358   void CplexBase::_setRowLowerBound(int i, Value lb)
   359   {
   360     LEMON_ASSERT(lb != INF, "Invalid bound");
   361     _set_row_bounds(i, lb, CplexBase::_getRowUpperBound(i));
   362   }
   363 
   364   void CplexBase::_setRowUpperBound(int i, Value ub)
   365   {
   366 
   367     LEMON_ASSERT(ub != -INF, "Invalid bound");
   368     _set_row_bounds(i, CplexBase::_getRowLowerBound(i), ub);
   369   }
   370 
   371   void CplexBase::_setObjCoeffs(ExprIterator b, ExprIterator e)
   372   {
   373     std::vector<int> indices;
   374     std::vector<Value> values;
   375     for(ExprIterator it=b; it!=e; ++it) {
   376       indices.push_back(it->first);
   377       values.push_back(it->second);
   378     }
   379     CPXchgobj(cplexEnv(), _prob, values.size(),
   380               &indices.front(), &values.front());
   381 
   382   }
   383 
   384   void CplexBase::_getObjCoeffs(InsertIterator b) const
   385   {
   386     int num = CPXgetnumcols(cplexEnv(), _prob);
   387     std::vector<Value> x(num);
   388 
   389     CPXgetobj(cplexEnv(), _prob, &x.front(), 0, num - 1);
   390     for (int i = 0; i < num; ++i) {
   391       if (x[i] != 0.0) {
   392         *b = std::make_pair(i, x[i]);
   393         ++b;
   394       }
   395     }
   396   }
   397 
   398   void CplexBase::_setObjCoeff(int i, Value obj_coef)
   399   {
   400     CPXchgobj(cplexEnv(), _prob, 1, &i, &obj_coef);
   401   }
   402 
   403   CplexBase::Value CplexBase::_getObjCoeff(int i) const
   404   {
   405     Value x;
   406     CPXgetobj(cplexEnv(), _prob, &x, i, i);
   407     return x;
   408   }
   409 
   410   void CplexBase::_setSense(CplexBase::Sense sense) {
   411     switch (sense) {
   412     case MIN:
   413       CPXchgobjsen(cplexEnv(), _prob, CPX_MIN);
   414       break;
   415     case MAX:
   416       CPXchgobjsen(cplexEnv(), _prob, CPX_MAX);
   417       break;
   418     }
   419   }
   420 
   421   CplexBase::Sense CplexBase::_getSense() const {
   422     switch (CPXgetobjsen(cplexEnv(), _prob)) {
   423     case CPX_MIN:
   424       return MIN;
   425     case CPX_MAX:
   426       return MAX;
   427     default:
   428       LEMON_ASSERT(false, "Invalid sense");
   429       return CplexBase::Sense();
   430     }
   431   }
   432 
   433   void CplexBase::_clear() {
   434     CPXfreeprob(cplexEnv(),&_prob);
   435     int status;
   436     _prob = CPXcreateprob(cplexEnv(), &status, "Cplex problem");
   437     rows.clear();
   438     cols.clear();
   439   }
   440 
   441   // CplexLp members
   442 
   443   CplexLp::CplexLp()
   444     : LpBase(), CplexBase(), LpSolver() {}
   445 
   446   CplexLp::CplexLp(const CplexEnv& env)
   447     : LpBase(), CplexBase(env), LpSolver() {}
   448 
   449   CplexLp::CplexLp(const CplexLp& other)
   450     : LpBase(), CplexBase(other), LpSolver() {}
   451 
   452   CplexLp::~CplexLp() {}
   453 
   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(), CplexBase(), MipSolver() {
   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(), CplexBase(env), MipSolver() {
   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(), CplexBase(other), MipSolver() {}
   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.
   884     case CPXMIP_OPTIMAL_TOL:
   885       // Optimal soluton with the tolerance defined by epgap or epagap has
   886       // been found.
   887       return OPTIMAL;
   888       //This also exists in later issues
   889       //    case CPXMIP_UNBOUNDED:
   890       //return UNBOUNDED;
   891       case CPXMIP_INFEASIBLE:
   892         return INFEASIBLE;
   893     default:
   894       return UNDEFINED;
   895     }
   896     //Unboundedness not treated well: the following is from cplex 9.0 doc
   897     // About Unboundedness
   898 
   899     // The treatment of models that are unbounded involves a few
   900     // subtleties. Specifically, a declaration of unboundedness means that
   901     // ILOG CPLEX has determined that the model has an unbounded
   902     // ray. Given any feasible solution x with objective z, a multiple of
   903     // the unbounded ray can be added to x to give a feasible solution
   904     // with objective z-1 (or z+1 for maximization models). Thus, if a
   905     // feasible solution exists, then the optimal objective is
   906     // unbounded. Note that ILOG CPLEX has not necessarily concluded that
   907     // a feasible solution exists. Users can call the routine CPXsolninfo
   908     // to determine whether ILOG CPLEX has also concluded that the model
   909     // has a feasible solution.
   910   }
   911 
   912   CplexMip::Value CplexMip::_getSol(int i) const {
   913     Value x;
   914     CPXgetmipx(cplexEnv(), _prob, &x, i, i);
   915     return x;
   916   }
   917 
   918   CplexMip::Value CplexMip::_getSolValue() const {
   919     Value objval;
   920     CPXgetmipobjval(cplexEnv(), _prob, &objval);
   921     return objval;
   922   }
   923 
   924 } //namespace lemon
   925