lemon/lp_glpk.cc
author alpar
Fri, 03 Feb 2006 09:18:17 +0000
changeset 1949 5db4ff8d69de
parent 1875 98698b69a902
child 1956 a055123339d5
permissions -rw-r--r--
Fight with Doxygen.
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     1 /* -*- C++ -*-
     2  * lemon/lp_glpk.cc - Part of LEMON, a generic C++ optimization library
     3  *
     4  * Copyright (C) 2006 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
     5  * (Egervary Research Group on Combinatorial Optimization, EGRES).
     6  *
     7  * Permission to use, modify and distribute this software is granted
     8  * provided that this copyright notice appears in all copies. For
     9  * precise terms see the accompanying LICENSE file.
    10  *
    11  * This software is provided "AS IS" with no warranty of any kind,
    12  * express or implied, and with no claim as to its suitability for any
    13  * purpose.
    14  *
    15  */
    16 
    17 #ifndef LEMON_LP_GLPK_CC
    18 #define LEMON_LP_GLPK_CC
    19 
    20 ///\file
    21 ///\brief Implementation of the LEMON-GLPK lp solver interface.
    22 
    23 #include <lemon/lp_glpk.h>
    24 //#include <iostream>
    25 namespace lemon {
    26 
    27 
    28   LpGlpk::LpGlpk() : Parent(), 
    29 		     lp(lpx_create_prob()) {
    30     ///\todo constrol function for this:
    31     lpx_set_int_parm(lp, LPX_K_DUAL, 1);
    32     messageLevel(0);
    33   }
    34   
    35   LpGlpk::~LpGlpk() {
    36     lpx_delete_prob(lp);
    37   }
    38   
    39   int LpGlpk::_addCol() { 
    40     int i=lpx_add_cols(lp, 1);
    41     _setColLowerBound(i, -INF);
    42     _setColUpperBound(i, INF);
    43     return i;
    44   }
    45 
    46   ///\e
    47 
    48 
    49   LpSolverBase &LpGlpk::_newLp()
    50   {
    51     LpGlpk* newlp=new LpGlpk();
    52     return *newlp;
    53   }
    54   
    55   ///\e
    56 
    57   LpSolverBase &LpGlpk::_copyLp()
    58   {
    59     LpGlpk* newlp=new LpGlpk();
    60 
    61     //Coefficient matrix, row bounds
    62     lpx_add_rows(newlp->lp, lpx_get_num_rows(lp));
    63     lpx_add_cols(newlp->lp, lpx_get_num_cols(lp));
    64     int len;
    65     int ind[1+lpx_get_num_cols(lp)];
    66     Value val[1+lpx_get_num_cols(lp)];
    67     for (int i=1;i<=lpx_get_num_rows(lp);++i){
    68       len=lpx_get_mat_row(lp,i,ind,val);
    69       lpx_set_mat_row(newlp->lp, i,len,ind,val);
    70       lpx_set_row_bnds(newlp->lp,i,lpx_get_row_type(lp,i),
    71 		       lpx_get_row_lb(lp,i),lpx_get_row_ub(lp,i));
    72     }
    73 
    74     //Objective function, coloumn bounds
    75     lpx_set_obj_dir(newlp->lp, lpx_get_obj_dir(lp));
    76     //Objectif function's constant term treated separately
    77     lpx_set_obj_coef(newlp->lp,0,lpx_get_obj_coef(lp,0));
    78     for (int i=1;i<=lpx_get_num_cols(lp);++i){
    79       lpx_set_obj_coef(newlp->lp,i,lpx_get_obj_coef(lp,i));
    80       lpx_set_col_bnds(newlp->lp,i,lpx_get_col_type(lp,i),
    81 		       lpx_get_col_lb(lp,i),lpx_get_col_ub(lp,i));
    82       
    83       
    84     }
    85 
    86     return *newlp;
    87   }
    88 
    89   int LpGlpk::_addRow() { 
    90     int i=lpx_add_rows(lp, 1);
    91     return i;
    92   }
    93 
    94   
    95   void LpGlpk::_eraseCol(int i) {
    96     int cols[2];
    97     cols[1]=i;
    98     lpx_del_cols(lp, 1, cols);
    99   }
   100   
   101   void LpGlpk::_eraseRow(int i) {
   102     int rows[2];
   103     rows[1]=i;
   104     lpx_del_rows(lp, 1, rows);
   105   }
   106 
   107   void LpGlpk::_getColName(int col, std::string & name)
   108   {
   109     
   110     char *n = lpx_get_col_name(lp,col);
   111     name = n?n:"";
   112   }
   113   
   114   
   115   void LpGlpk::_setColName(int col, const std::string & name)
   116   {
   117     lpx_set_col_name(lp,col,const_cast<char*>(name.c_str()));
   118   }
   119   
   120   void LpGlpk::_setRowCoeffs(int i, 
   121 			     int length,
   122 			     const int   * indices, 
   123 			     const Value   * values )
   124   {
   125     lpx_set_mat_row(lp, i, length,
   126 		    const_cast<int * >(indices) ,
   127 		    const_cast<Value * >(values));
   128   }
   129   
   130   void LpGlpk::_setColCoeffs(int i, 
   131 			     int length,
   132 			     const int   * indices, 
   133 			     const Value   * values)
   134   {
   135     lpx_set_mat_col(lp, i, length,
   136 		    const_cast<int * >(indices),
   137 		    const_cast<Value * >(values));
   138   }
   139 
   140 
   141   void LpGlpk::_setCoeff(int row, int col, Value value) 
   142   {
   143     ///FIXME Of course this is not efficient at all, but GLPK knows not more.
   144     // First approach: get one row, apply changes and set it again
   145     //(one idea to improve this: maybe it is better to do this with 1 coloumn)
   146     
   147     int mem_length=2+lpx_get_num_cols(lp);
   148     int* indices = new int[mem_length];
   149     Value* values = new Value[mem_length];
   150     
   151 
   152     int length=lpx_get_mat_row(lp, row, indices, values);
   153 
   154     //The following code does not suppose that the elements of the array indices are sorted
   155     int i=1;
   156     bool found=false;
   157     while (i <= length && !found){
   158       if (indices[i]==col){
   159 	found = true;
   160 	values[i]=value;
   161       }
   162       ++i;
   163     }
   164     if (!found){
   165       ++length;
   166       indices[length]=col;
   167       values[length]=value;
   168     }
   169     
   170     lpx_set_mat_row(lp, row, length, indices, values);
   171     delete [] indices;
   172     delete [] values;
   173     
   174   }
   175 
   176   void LpGlpk::_setColLowerBound(int i, Value lo)
   177   {
   178     if (lo==INF) {
   179       //FIXME error
   180     }
   181     int b=lpx_get_col_type(lp, i);
   182     double up=lpx_get_col_ub(lp, i);	
   183     if (lo==-INF) {
   184       switch (b) {
   185       case LPX_FR:
   186       case LPX_LO:
   187 	lpx_set_col_bnds(lp, i, LPX_FR, lo, up);
   188 	break;
   189       case LPX_UP:
   190 	break;
   191       case LPX_DB:
   192       case LPX_FX:
   193 	lpx_set_col_bnds(lp, i, LPX_UP, lo, up);
   194 	break;
   195       default: ;
   196 	//FIXME error
   197       }
   198     } else {
   199       switch (b) {
   200       case LPX_FR:
   201       case LPX_LO:
   202 	lpx_set_col_bnds(lp, i, LPX_LO, lo, up);
   203 	break;
   204       case LPX_UP:	  
   205       case LPX_DB:
   206       case LPX_FX:
   207 	if (lo==up) 
   208 	  lpx_set_col_bnds(lp, i, LPX_FX, lo, up);
   209 	else 
   210 	  lpx_set_col_bnds(lp, i, LPX_DB, lo, up);
   211 	break;
   212       default: ;
   213 	//FIXME error
   214       }
   215     }
   216 
   217   }
   218   
   219   void LpGlpk::_setColUpperBound(int i, Value up)
   220   {
   221     if (up==-INF) {
   222       //FIXME error
   223     }
   224     int b=lpx_get_col_type(lp, i);
   225     double lo=lpx_get_col_lb(lp, i);
   226     if (up==INF) {
   227       switch (b) {
   228       case LPX_FR:
   229       case LPX_LO:
   230 	break;
   231       case LPX_UP:
   232 	lpx_set_col_bnds(lp, i, LPX_FR, lo, up);
   233 	break;
   234       case LPX_DB:
   235       case LPX_FX:
   236 	lpx_set_col_bnds(lp, i, LPX_LO, lo, up);
   237 	break;
   238       default: ;
   239 	//FIXME error
   240       }
   241     } else {
   242       switch (b) {
   243       case LPX_FR:
   244 	lpx_set_col_bnds(lp, i, LPX_UP, lo, up);
   245 	break;
   246       case LPX_UP:
   247 	lpx_set_col_bnds(lp, i, LPX_UP, lo, up);
   248 	break;
   249       case LPX_LO:
   250       case LPX_DB:
   251       case LPX_FX:
   252 	if (lo==up) 
   253 	  lpx_set_col_bnds(lp, i, LPX_FX, lo, up);
   254 	else 
   255 	  lpx_set_col_bnds(lp, i, LPX_DB, lo, up);
   256 	break;
   257       default: ;
   258 	//FIXME error
   259       }
   260     }
   261   }
   262   
   263 //   void LpGlpk::_setRowLowerBound(int i, Value lo)
   264 //   {
   265 //     if (lo==INF) {
   266 //       //FIXME error
   267 //     }
   268 //     int b=lpx_get_row_type(lp, i);
   269 //     double up=lpx_get_row_ub(lp, i);	
   270 //     if (lo==-INF) {
   271 //       switch (b) {
   272 //       case LPX_FR:
   273 //       case LPX_LO:
   274 // 	lpx_set_row_bnds(lp, i, LPX_FR, lo, up);
   275 // 	break;
   276 //       case LPX_UP:
   277 // 	break;
   278 //       case LPX_DB:
   279 //       case LPX_FX:
   280 // 	lpx_set_row_bnds(lp, i, LPX_UP, lo, up);
   281 // 	break;
   282 //       default: ;
   283 // 	//FIXME error
   284 //       }
   285 //     } else {
   286 //       switch (b) {
   287 //       case LPX_FR:
   288 //       case LPX_LO:
   289 // 	lpx_set_row_bnds(lp, i, LPX_LO, lo, up);
   290 // 	break;
   291 //       case LPX_UP:	  
   292 //       case LPX_DB:
   293 //       case LPX_FX:
   294 // 	if (lo==up) 
   295 // 	  lpx_set_row_bnds(lp, i, LPX_FX, lo, up);
   296 // 	else 
   297 // 	  lpx_set_row_bnds(lp, i, LPX_DB, lo, up);
   298 // 	break;
   299 //       default: ;
   300 // 	//FIXME error
   301 //       }
   302 //     }
   303 //   }
   304   
   305 //   void LpGlpk::_setRowUpperBound(int i, Value up)
   306 //   {
   307 //     if (up==-INF) {
   308 //       //FIXME error
   309 //     }
   310 //     int b=lpx_get_row_type(lp, i);
   311 //     double lo=lpx_get_row_lb(lp, i);
   312 //     if (up==INF) {
   313 //       switch (b) {
   314 //       case LPX_FR:
   315 //       case LPX_LO:
   316 // 	break;
   317 //       case LPX_UP:
   318 // 	lpx_set_row_bnds(lp, i, LPX_FR, lo, up);
   319 // 	break;
   320 //       case LPX_DB:
   321 //       case LPX_FX:
   322 // 	lpx_set_row_bnds(lp, i, LPX_LO, lo, up);
   323 // 	break;
   324 //       default: ;
   325 // 	//FIXME error
   326 //       }
   327 //     } else {
   328 //       switch (b) {
   329 //       case LPX_FR:
   330 // 	lpx_set_row_bnds(lp, i, LPX_UP, lo, up);
   331 // 	break;
   332 //       case LPX_UP:
   333 // 	lpx_set_row_bnds(lp, i, LPX_UP, lo, up);
   334 // 	break;
   335 //       case LPX_LO:
   336 //       case LPX_DB:
   337 //       case LPX_FX:
   338 // 	if (lo==up) 
   339 // 	  lpx_set_row_bnds(lp, i, LPX_FX, lo, up);
   340 // 	else 
   341 // 	  lpx_set_row_bnds(lp, i, LPX_DB, lo, up);
   342 // 	break;
   343 //       default: ;
   344 // 	//FIXME error
   345 //       }
   346 //     }
   347 //   }
   348 
   349   void LpGlpk::_setRowBounds(int i, Value lb, Value ub)
   350   {
   351     //Bad parameter
   352     if (lb==INF || ub==-INF) {
   353       //FIXME error
   354     }
   355 
   356     if (lb == -INF){
   357       if (ub == INF){
   358 	lpx_set_row_bnds(lp, i, LPX_FR, lb, ub);
   359       }
   360       else{
   361 	lpx_set_row_bnds(lp, i, LPX_UP, lb, ub);
   362       }
   363     }
   364     else{
   365       if (ub==INF){
   366 	lpx_set_row_bnds(lp, i, LPX_LO, lb, ub);
   367 
   368       }
   369       else{
   370 	if (lb == ub){
   371 	  lpx_set_row_bnds(lp, i, LPX_FX, lb, ub);
   372 	}
   373 	else{
   374 	  lpx_set_row_bnds(lp, i, LPX_DB, lb, ub);
   375 	}
   376       }
   377     }
   378 
   379   }
   380   
   381   void LpGlpk::_setObjCoeff(int i, Value obj_coef)
   382   {
   383     //i=0 means the constant term (shift)
   384     lpx_set_obj_coef(lp, i, obj_coef);
   385   }
   386 
   387   void LpGlpk::_clearObj()
   388   {
   389     for (int i=0;i<=lpx_get_num_cols(lp);++i){
   390       lpx_set_obj_coef(lp, i, 0);
   391     }
   392   }
   393 //   void LpGlpk::_setObj(int length,
   394 // 		       int  const * indices, 
   395 // 		       Value  const * values )
   396 //   {
   397 //     Value new_values[1+lpx_num_cols()];
   398 //     for (i=0;i<=lpx_num_cols();++i){
   399 //       new_values[i]=0;
   400 //     }
   401 //     for (i=1;i<=length;++i){
   402 //       new_values[indices[i]]=values[i];
   403 //     }
   404     
   405 //     for (i=0;i<=lpx_num_cols();++i){
   406 //       lpx_set_obj_coef(lp, i, new_values[i]);
   407 //     }
   408 //   }
   409 
   410   LpGlpk::SolveExitStatus LpGlpk::_solve()
   411   {
   412     int i =  lpx_simplex(lp);
   413     switch (i) {
   414     case LPX_E_OK: 
   415       return SOLVED;
   416     default:
   417       return UNSOLVED;
   418     }
   419   }
   420 
   421   LpGlpk::Value LpGlpk::_getPrimal(int i)
   422   {
   423     return lpx_get_col_prim(lp,i);
   424   }
   425 
   426   LpGlpk::Value LpGlpk::_getDual(int i)
   427   {
   428     return lpx_get_row_dual(lp,i);
   429   }
   430   
   431   LpGlpk::Value LpGlpk::_getPrimalValue()
   432   {
   433     return lpx_get_obj_val(lp);
   434   }
   435   bool LpGlpk::_isBasicCol(int i) {
   436     return (lpx_get_col_stat(lp, i)==LPX_BS);
   437   }
   438   
   439  
   440   LpGlpk::SolutionStatus LpGlpk::_getPrimalStatus()
   441   {
   442     int stat=  lpx_get_status(lp);
   443     switch (stat) {
   444     case LPX_UNDEF://Undefined (no solve has been run yet)
   445       return UNDEFINED;
   446     case LPX_NOFEAS://There is no feasible solution (primal, I guess)
   447     case LPX_INFEAS://Infeasible 
   448       return INFEASIBLE;
   449     case LPX_UNBND://Unbounded
   450       return INFINITE;
   451     case LPX_FEAS://Feasible
   452       return FEASIBLE;
   453     case LPX_OPT://Feasible
   454       return OPTIMAL;
   455     default:
   456       return UNDEFINED; //to avoid gcc warning
   457       //FIXME error
   458     }
   459   }
   460 
   461   LpGlpk::SolutionStatus LpGlpk::_getDualStatus()
   462   {
   463 //     std::cout<<"Itt megy: "<<lpx_get_dual_stat(lp)<<std::endl;
   464 //     std::cout<<"Itt a primal: "<<lpx_get_prim_stat(lp)<<std::endl;
   465 
   466     switch (lpx_get_dual_stat(lp)) {
   467     case LPX_D_UNDEF://Undefined (no solve has been run yet)
   468       return UNDEFINED;
   469     case LPX_D_NOFEAS://There is no dual feasible solution 
   470 //    case LPX_D_INFEAS://Infeasible 
   471       return INFEASIBLE;
   472     case LPX_D_FEAS://Feasible    
   473       switch (lpx_get_status(lp)) {
   474       case LPX_NOFEAS:
   475 	return INFINITE;
   476       case LPX_OPT:
   477 	return OPTIMAL;
   478       default:
   479 	return FEASIBLE;
   480       }
   481     default:
   482       return UNDEFINED; //to avoid gcc warning
   483       //FIXME error
   484     }
   485   }
   486 
   487   LpGlpk::ProblemTypes LpGlpk::_getProblemType()
   488   {
   489       //int stat=  lpx_get_status(lp);
   490     int statp=  lpx_get_prim_stat(lp);
   491     int statd=  lpx_get_dual_stat(lp);
   492     if (statp==LPX_P_FEAS && statd==LPX_D_FEAS)
   493 	return PRIMAL_DUAL_FEASIBLE;
   494     if (statp==LPX_P_FEAS && statd==LPX_D_NOFEAS)
   495 	return PRIMAL_FEASIBLE_DUAL_INFEASIBLE;
   496     if (statp==LPX_P_NOFEAS && statd==LPX_D_FEAS)
   497 	return PRIMAL_INFEASIBLE_DUAL_FEASIBLE;
   498     if (statp==LPX_P_NOFEAS && statd==LPX_D_NOFEAS)
   499 	return PRIMAL_DUAL_INFEASIBLE;
   500     //In all other cases
   501     return UNKNOWN;
   502   }
   503 
   504   void LpGlpk::_setMax()
   505   {
   506     lpx_set_obj_dir(lp, LPX_MAX);
   507   }
   508 
   509   void LpGlpk::_setMin()
   510   {
   511     lpx_set_obj_dir(lp, LPX_MIN);
   512   }
   513 
   514  
   515   void LpGlpk::messageLevel(int m)
   516   {
   517     lpx_set_int_parm(lp, LPX_K_MSGLEV, m);
   518   }
   519 
   520   void LpGlpk::presolver(bool b)
   521   {
   522     lpx_set_int_parm(lp, LPX_K_PRESOL, b);
   523   }
   524 
   525  
   526 } //END OF NAMESPACE LEMON
   527 
   528 #endif //LEMON_LP_GLPK_CC