src/glpapi01.c
changeset 1 c445c931472f
equal deleted inserted replaced
-1:000000000000 0:f557e813b4db
       
     1 /* glpapi01.c (problem creating and modifying routines) */
       
     2 
       
     3 /***********************************************************************
       
     4 *  This code is part of GLPK (GNU Linear Programming Kit).
       
     5 *
       
     6 *  Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,
       
     7 *  2009, 2010 Andrew Makhorin, Department for Applied Informatics,
       
     8 *  Moscow Aviation Institute, Moscow, Russia. All rights reserved.
       
     9 *  E-mail: <mao@gnu.org>.
       
    10 *
       
    11 *  GLPK is free software: you can redistribute it and/or modify it
       
    12 *  under the terms of the GNU General Public License as published by
       
    13 *  the Free Software Foundation, either version 3 of the License, or
       
    14 *  (at your option) any later version.
       
    15 *
       
    16 *  GLPK is distributed in the hope that it will be useful, but WITHOUT
       
    17 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
       
    18 *  or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
       
    19 *  License for more details.
       
    20 *
       
    21 *  You should have received a copy of the GNU General Public License
       
    22 *  along with GLPK. If not, see <http://www.gnu.org/licenses/>.
       
    23 ***********************************************************************/
       
    24 
       
    25 #include "glpios.h"
       
    26 
       
    27 /* CAUTION: DO NOT CHANGE THE LIMITS BELOW */
       
    28 
       
    29 #define M_MAX 100000000 /* = 100*10^6 */
       
    30 /* maximal number of rows in the problem object */
       
    31 
       
    32 #define N_MAX 100000000 /* = 100*10^6 */
       
    33 /* maximal number of columns in the problem object */
       
    34 
       
    35 #define NNZ_MAX 500000000 /* = 500*10^6 */
       
    36 /* maximal number of constraint coefficients in the problem object */
       
    37 
       
    38 /***********************************************************************
       
    39 *  NAME
       
    40 *
       
    41 *  glp_create_prob - create problem object
       
    42 *
       
    43 *  SYNOPSIS
       
    44 *
       
    45 *  glp_prob *glp_create_prob(void);
       
    46 *
       
    47 *  DESCRIPTION
       
    48 *
       
    49 *  The routine glp_create_prob creates a new problem object, which is
       
    50 *  initially "empty", i.e. has no rows and columns.
       
    51 *
       
    52 *  RETURNS
       
    53 *
       
    54 *  The routine returns a pointer to the object created, which should be
       
    55 *  used in any subsequent operations on this object. */
       
    56 
       
    57 static void create_prob(glp_prob *lp)
       
    58 {     lp->magic = GLP_PROB_MAGIC;
       
    59       lp->pool = dmp_create_pool();
       
    60 #if 0 /* 17/XI-2009 */
       
    61       lp->cps = xmalloc(sizeof(struct LPXCPS));
       
    62       lpx_reset_parms(lp);
       
    63 #else
       
    64       lp->parms = NULL;
       
    65 #endif
       
    66       lp->tree = NULL;
       
    67 #if 0
       
    68       lp->lwa = 0;
       
    69       lp->cwa = NULL;
       
    70 #endif
       
    71       /* LP/MIP data */
       
    72       lp->name = NULL;
       
    73       lp->obj = NULL;
       
    74       lp->dir = GLP_MIN;
       
    75       lp->c0 = 0.0;
       
    76       lp->m_max = 100;
       
    77       lp->n_max = 200;
       
    78       lp->m = lp->n = 0;
       
    79       lp->nnz = 0;
       
    80       lp->row = xcalloc(1+lp->m_max, sizeof(GLPROW *));
       
    81       lp->col = xcalloc(1+lp->n_max, sizeof(GLPCOL *));
       
    82       lp->r_tree = lp->c_tree = NULL;
       
    83       /* basis factorization */
       
    84       lp->valid = 0;
       
    85       lp->head = xcalloc(1+lp->m_max, sizeof(int));
       
    86       lp->bfcp = NULL;
       
    87       lp->bfd = NULL;
       
    88       /* basic solution (LP) */
       
    89       lp->pbs_stat = lp->dbs_stat = GLP_UNDEF;
       
    90       lp->obj_val = 0.0;
       
    91       lp->it_cnt = 0;
       
    92       lp->some = 0;
       
    93       /* interior-point solution (LP) */
       
    94       lp->ipt_stat = GLP_UNDEF;
       
    95       lp->ipt_obj = 0.0;
       
    96       /* integer solution (MIP) */
       
    97       lp->mip_stat = GLP_UNDEF;
       
    98       lp->mip_obj = 0.0;
       
    99       return;
       
   100 }
       
   101 
       
   102 glp_prob *glp_create_prob(void)
       
   103 {     glp_prob *lp;
       
   104       lp = xmalloc(sizeof(glp_prob));
       
   105       create_prob(lp);
       
   106       return lp;
       
   107 }
       
   108 
       
   109 /***********************************************************************
       
   110 *  NAME
       
   111 *
       
   112 *  glp_set_prob_name - assign (change) problem name
       
   113 *
       
   114 *  SYNOPSIS
       
   115 *
       
   116 *  void glp_set_prob_name(glp_prob *lp, const char *name);
       
   117 *
       
   118 *  DESCRIPTION
       
   119 *
       
   120 *  The routine glp_set_prob_name assigns a given symbolic name (1 up to
       
   121 *  255 characters) to the specified problem object.
       
   122 *
       
   123 *  If the parameter name is NULL or empty string, the routine erases an
       
   124 *  existing symbolic name of the problem object. */
       
   125 
       
   126 void glp_set_prob_name(glp_prob *lp, const char *name)
       
   127 {     glp_tree *tree = lp->tree;
       
   128       if (tree != NULL && tree->reason != 0)
       
   129          xerror("glp_set_prob_name: operation not allowed\n");
       
   130       if (lp->name != NULL)
       
   131       {  dmp_free_atom(lp->pool, lp->name, strlen(lp->name)+1);
       
   132          lp->name = NULL;
       
   133       }
       
   134       if (!(name == NULL || name[0] == '\0'))
       
   135       {  int k;
       
   136          for (k = 0; name[k] != '\0'; k++)
       
   137          {  if (k == 256)
       
   138                xerror("glp_set_prob_name: problem name too long\n");
       
   139             if (iscntrl((unsigned char)name[k]))
       
   140                xerror("glp_set_prob_name: problem name contains invalid"
       
   141                   " character(s)\n");
       
   142          }
       
   143          lp->name = dmp_get_atom(lp->pool, strlen(name)+1);
       
   144          strcpy(lp->name, name);
       
   145       }
       
   146       return;
       
   147 }
       
   148 
       
   149 /***********************************************************************
       
   150 *  NAME
       
   151 *
       
   152 *  glp_set_obj_name - assign (change) objective function name
       
   153 *
       
   154 *  SYNOPSIS
       
   155 *
       
   156 *  void glp_set_obj_name(glp_prob *lp, const char *name);
       
   157 *
       
   158 *  DESCRIPTION
       
   159 *
       
   160 *  The routine glp_set_obj_name assigns a given symbolic name (1 up to
       
   161 *  255 characters) to the objective function of the specified problem
       
   162 *  object.
       
   163 *
       
   164 *  If the parameter name is NULL or empty string, the routine erases an
       
   165 *  existing name of the objective function. */
       
   166 
       
   167 void glp_set_obj_name(glp_prob *lp, const char *name)
       
   168 {     glp_tree *tree = lp->tree;
       
   169       if (tree != NULL && tree->reason != 0)
       
   170          xerror("glp_set_obj_name: operation not allowed\n");
       
   171      if (lp->obj != NULL)
       
   172       {  dmp_free_atom(lp->pool, lp->obj, strlen(lp->obj)+1);
       
   173          lp->obj = NULL;
       
   174       }
       
   175       if (!(name == NULL || name[0] == '\0'))
       
   176       {  int k;
       
   177          for (k = 0; name[k] != '\0'; k++)
       
   178          {  if (k == 256)
       
   179                xerror("glp_set_obj_name: objective name too long\n");
       
   180             if (iscntrl((unsigned char)name[k]))
       
   181                xerror("glp_set_obj_name: objective name contains invali"
       
   182                   "d character(s)\n");
       
   183          }
       
   184          lp->obj = dmp_get_atom(lp->pool, strlen(name)+1);
       
   185          strcpy(lp->obj, name);
       
   186       }
       
   187       return;
       
   188 }
       
   189 
       
   190 /***********************************************************************
       
   191 *  NAME
       
   192 *
       
   193 *  glp_set_obj_dir - set (change) optimization direction flag
       
   194 *
       
   195 *  SYNOPSIS
       
   196 *
       
   197 *  void glp_set_obj_dir(glp_prob *lp, int dir);
       
   198 *
       
   199 *  DESCRIPTION
       
   200 *
       
   201 *  The routine glp_set_obj_dir sets (changes) optimization direction
       
   202 *  flag (i.e. "sense" of the objective function) as specified by the
       
   203 *  parameter dir:
       
   204 *
       
   205 *  GLP_MIN - minimization;
       
   206 *  GLP_MAX - maximization. */
       
   207 
       
   208 void glp_set_obj_dir(glp_prob *lp, int dir)
       
   209 {     glp_tree *tree = lp->tree;
       
   210       if (tree != NULL && tree->reason != 0)
       
   211          xerror("glp_set_obj_dir: operation not allowed\n");
       
   212      if (!(dir == GLP_MIN || dir == GLP_MAX))
       
   213          xerror("glp_set_obj_dir: dir = %d; invalid direction flag\n",
       
   214             dir);
       
   215       lp->dir = dir;
       
   216       return;
       
   217 }
       
   218 
       
   219 /***********************************************************************
       
   220 *  NAME
       
   221 *
       
   222 *  glp_add_rows - add new rows to problem object
       
   223 *
       
   224 *  SYNOPSIS
       
   225 *
       
   226 *  int glp_add_rows(glp_prob *lp, int nrs);
       
   227 *
       
   228 *  DESCRIPTION
       
   229 *
       
   230 *  The routine glp_add_rows adds nrs rows (constraints) to the specified
       
   231 *  problem object. New rows are always added to the end of the row list,
       
   232 *  so the ordinal numbers of existing rows remain unchanged.
       
   233 *
       
   234 *  Being added each new row is initially free (unbounded) and has empty
       
   235 *  list of the constraint coefficients.
       
   236 *
       
   237 *  RETURNS
       
   238 *
       
   239 *  The routine glp_add_rows returns the ordinal number of the first new
       
   240 *  row added to the problem object. */
       
   241 
       
   242 int glp_add_rows(glp_prob *lp, int nrs)
       
   243 {     glp_tree *tree = lp->tree;
       
   244       GLPROW *row;
       
   245       int m_new, i;
       
   246       /* determine new number of rows */
       
   247       if (nrs < 1)
       
   248          xerror("glp_add_rows: nrs = %d; invalid number of rows\n",
       
   249             nrs);
       
   250       if (nrs > M_MAX - lp->m)
       
   251          xerror("glp_add_rows: nrs = %d; too many rows\n", nrs);
       
   252       m_new = lp->m + nrs;
       
   253       /* increase the room, if necessary */
       
   254       if (lp->m_max < m_new)
       
   255       {  GLPROW **save = lp->row;
       
   256          while (lp->m_max < m_new)
       
   257          {  lp->m_max += lp->m_max;
       
   258             xassert(lp->m_max > 0);
       
   259          }
       
   260          lp->row = xcalloc(1+lp->m_max, sizeof(GLPROW *));
       
   261          memcpy(&lp->row[1], &save[1], lp->m * sizeof(GLPROW *));
       
   262          xfree(save);
       
   263          /* do not forget about the basis header */
       
   264          xfree(lp->head);
       
   265          lp->head = xcalloc(1+lp->m_max, sizeof(int));
       
   266       }
       
   267       /* add new rows to the end of the row list */
       
   268       for (i = lp->m+1; i <= m_new; i++)
       
   269       {  /* create row descriptor */
       
   270          lp->row[i] = row = dmp_get_atom(lp->pool, sizeof(GLPROW));
       
   271          row->i = i;
       
   272          row->name = NULL;
       
   273          row->node = NULL;
       
   274 #if 1 /* 20/IX-2008 */
       
   275          row->level = 0;
       
   276          row->origin = 0;
       
   277          row->klass = 0;
       
   278          if (tree != NULL)
       
   279          {  switch (tree->reason)
       
   280             {  case 0:
       
   281                   break;
       
   282                case GLP_IROWGEN:
       
   283                   xassert(tree->curr != NULL);
       
   284                   row->level = tree->curr->level;
       
   285                   row->origin = GLP_RF_LAZY;
       
   286                   break;
       
   287                case GLP_ICUTGEN:
       
   288                   xassert(tree->curr != NULL);
       
   289                   row->level = tree->curr->level;
       
   290                   row->origin = GLP_RF_CUT;
       
   291                   break;
       
   292                default:
       
   293                   xassert(tree != tree);
       
   294             }
       
   295          }
       
   296 #endif
       
   297          row->type = GLP_FR;
       
   298          row->lb = row->ub = 0.0;
       
   299          row->ptr = NULL;
       
   300          row->rii = 1.0;
       
   301          row->stat = GLP_BS;
       
   302 #if 0
       
   303          row->bind = -1;
       
   304 #else
       
   305          row->bind = 0;
       
   306 #endif
       
   307          row->prim = row->dual = 0.0;
       
   308          row->pval = row->dval = 0.0;
       
   309          row->mipx = 0.0;
       
   310       }
       
   311       /* set new number of rows */
       
   312       lp->m = m_new;
       
   313       /* invalidate the basis factorization */
       
   314       lp->valid = 0;
       
   315 #if 1
       
   316       if (tree != NULL && tree->reason != 0) tree->reopt = 1;
       
   317 #endif
       
   318       /* return the ordinal number of the first row added */
       
   319       return m_new - nrs + 1;
       
   320 }
       
   321 
       
   322 /***********************************************************************
       
   323 *  NAME
       
   324 *
       
   325 *  glp_add_cols - add new columns to problem object
       
   326 *
       
   327 *  SYNOPSIS
       
   328 *
       
   329 *  int glp_add_cols(glp_prob *lp, int ncs);
       
   330 *
       
   331 *  DESCRIPTION
       
   332 *
       
   333 *  The routine glp_add_cols adds ncs columns (structural variables) to
       
   334 *  the specified problem object. New columns are always added to the end
       
   335 *  of the column list, so the ordinal numbers of existing columns remain
       
   336 *  unchanged.
       
   337 *
       
   338 *  Being added each new column is initially fixed at zero and has empty
       
   339 *  list of the constraint coefficients.
       
   340 *
       
   341 *  RETURNS
       
   342 *
       
   343 *  The routine glp_add_cols returns the ordinal number of the first new
       
   344 *  column added to the problem object. */
       
   345 
       
   346 int glp_add_cols(glp_prob *lp, int ncs)
       
   347 {     glp_tree *tree = lp->tree;
       
   348       GLPCOL *col;
       
   349       int n_new, j;
       
   350       if (tree != NULL && tree->reason != 0)
       
   351          xerror("glp_add_cols: operation not allowed\n");
       
   352       /* determine new number of columns */
       
   353       if (ncs < 1)
       
   354          xerror("glp_add_cols: ncs = %d; invalid number of columns\n",
       
   355             ncs);
       
   356       if (ncs > N_MAX - lp->n)
       
   357          xerror("glp_add_cols: ncs = %d; too many columns\n", ncs);
       
   358       n_new = lp->n + ncs;
       
   359       /* increase the room, if necessary */
       
   360       if (lp->n_max < n_new)
       
   361       {  GLPCOL **save = lp->col;
       
   362          while (lp->n_max < n_new)
       
   363          {  lp->n_max += lp->n_max;
       
   364             xassert(lp->n_max > 0);
       
   365          }
       
   366          lp->col = xcalloc(1+lp->n_max, sizeof(GLPCOL *));
       
   367          memcpy(&lp->col[1], &save[1], lp->n * sizeof(GLPCOL *));
       
   368          xfree(save);
       
   369       }
       
   370       /* add new columns to the end of the column list */
       
   371       for (j = lp->n+1; j <= n_new; j++)
       
   372       {  /* create column descriptor */
       
   373          lp->col[j] = col = dmp_get_atom(lp->pool, sizeof(GLPCOL));
       
   374          col->j = j;
       
   375          col->name = NULL;
       
   376          col->node = NULL;
       
   377          col->kind = GLP_CV;
       
   378          col->type = GLP_FX;
       
   379          col->lb = col->ub = 0.0;
       
   380          col->coef = 0.0;
       
   381          col->ptr = NULL;
       
   382          col->sjj = 1.0;
       
   383          col->stat = GLP_NS;
       
   384 #if 0
       
   385          col->bind = -1;
       
   386 #else
       
   387          col->bind = 0; /* the basis may remain valid */
       
   388 #endif
       
   389          col->prim = col->dual = 0.0;
       
   390          col->pval = col->dval = 0.0;
       
   391          col->mipx = 0.0;
       
   392       }
       
   393       /* set new number of columns */
       
   394       lp->n = n_new;
       
   395       /* return the ordinal number of the first column added */
       
   396       return n_new - ncs + 1;
       
   397 }
       
   398 
       
   399 /***********************************************************************
       
   400 *  NAME
       
   401 *
       
   402 *  glp_set_row_name - assign (change) row name
       
   403 *
       
   404 *  SYNOPSIS
       
   405 *
       
   406 *  void glp_set_row_name(glp_prob *lp, int i, const char *name);
       
   407 *
       
   408 *  DESCRIPTION
       
   409 *
       
   410 *  The routine glp_set_row_name assigns a given symbolic name (1 up to
       
   411 *  255 characters) to i-th row (auxiliary variable) of the specified
       
   412 *  problem object.
       
   413 *
       
   414 *  If the parameter name is NULL or empty string, the routine erases an
       
   415 *  existing name of i-th row. */
       
   416 
       
   417 void glp_set_row_name(glp_prob *lp, int i, const char *name)
       
   418 {     glp_tree *tree = lp->tree;
       
   419       GLPROW *row;
       
   420       if (!(1 <= i && i <= lp->m))
       
   421          xerror("glp_set_row_name: i = %d; row number out of range\n",
       
   422             i);
       
   423       row = lp->row[i];
       
   424       if (tree != NULL && tree->reason != 0)
       
   425       {  xassert(tree->curr != NULL);
       
   426          xassert(row->level == tree->curr->level);
       
   427       }
       
   428       if (row->name != NULL)
       
   429       {  if (row->node != NULL)
       
   430          {  xassert(lp->r_tree != NULL);
       
   431             avl_delete_node(lp->r_tree, row->node);
       
   432             row->node = NULL;
       
   433          }
       
   434          dmp_free_atom(lp->pool, row->name, strlen(row->name)+1);
       
   435          row->name = NULL;
       
   436       }
       
   437       if (!(name == NULL || name[0] == '\0'))
       
   438       {  int k;
       
   439          for (k = 0; name[k] != '\0'; k++)
       
   440          {  if (k == 256)
       
   441                xerror("glp_set_row_name: i = %d; row name too long\n",
       
   442                   i);
       
   443             if (iscntrl((unsigned char)name[k]))
       
   444                xerror("glp_set_row_name: i = %d: row name contains inva"
       
   445                   "lid character(s)\n", i);
       
   446          }
       
   447          row->name = dmp_get_atom(lp->pool, strlen(name)+1);
       
   448          strcpy(row->name, name);
       
   449          if (lp->r_tree != NULL)
       
   450          {  xassert(row->node == NULL);
       
   451             row->node = avl_insert_node(lp->r_tree, row->name);
       
   452             avl_set_node_link(row->node, row);
       
   453          }
       
   454       }
       
   455       return;
       
   456 }
       
   457 
       
   458 /***********************************************************************
       
   459 *  NAME
       
   460 *
       
   461 *  glp_set_col_name - assign (change) column name
       
   462 *
       
   463 *  SYNOPSIS
       
   464 *
       
   465 *  void glp_set_col_name(glp_prob *lp, int j, const char *name);
       
   466 *
       
   467 *  DESCRIPTION
       
   468 *
       
   469 *  The routine glp_set_col_name assigns a given symbolic name (1 up to
       
   470 *  255 characters) to j-th column (structural variable) of the specified
       
   471 *  problem object.
       
   472 *
       
   473 *  If the parameter name is NULL or empty string, the routine erases an
       
   474 *  existing name of j-th column. */
       
   475 
       
   476 void glp_set_col_name(glp_prob *lp, int j, const char *name)
       
   477 {     glp_tree *tree = lp->tree;
       
   478       GLPCOL *col;
       
   479       if (tree != NULL && tree->reason != 0)
       
   480          xerror("glp_set_col_name: operation not allowed\n");
       
   481       if (!(1 <= j && j <= lp->n))
       
   482          xerror("glp_set_col_name: j = %d; column number out of range\n"
       
   483             , j);
       
   484       col = lp->col[j];
       
   485       if (col->name != NULL)
       
   486       {  if (col->node != NULL)
       
   487          {  xassert(lp->c_tree != NULL);
       
   488             avl_delete_node(lp->c_tree, col->node);
       
   489             col->node = NULL;
       
   490          }
       
   491          dmp_free_atom(lp->pool, col->name, strlen(col->name)+1);
       
   492          col->name = NULL;
       
   493       }
       
   494       if (!(name == NULL || name[0] == '\0'))
       
   495       {  int k;
       
   496          for (k = 0; name[k] != '\0'; k++)
       
   497          {  if (k == 256)
       
   498                xerror("glp_set_col_name: j = %d; column name too long\n"
       
   499                   , j);
       
   500             if (iscntrl((unsigned char)name[k]))
       
   501                xerror("glp_set_col_name: j = %d: column name contains i"
       
   502                   "nvalid character(s)\n", j);
       
   503          }
       
   504          col->name = dmp_get_atom(lp->pool, strlen(name)+1);
       
   505          strcpy(col->name, name);
       
   506          if (lp->c_tree != NULL && col->name != NULL)
       
   507          {  xassert(col->node == NULL);
       
   508             col->node = avl_insert_node(lp->c_tree, col->name);
       
   509             avl_set_node_link(col->node, col);
       
   510          }
       
   511       }
       
   512       return;
       
   513 }
       
   514 
       
   515 /***********************************************************************
       
   516 *  NAME
       
   517 *
       
   518 *  glp_set_row_bnds - set (change) row bounds
       
   519 *
       
   520 *  SYNOPSIS
       
   521 *
       
   522 *  void glp_set_row_bnds(glp_prob *lp, int i, int type, double lb,
       
   523 *     double ub);
       
   524 *
       
   525 *  DESCRIPTION
       
   526 *
       
   527 *  The routine glp_set_row_bnds sets (changes) the type and bounds of
       
   528 *  i-th row (auxiliary variable) of the specified problem object.
       
   529 *
       
   530 *  Parameters type, lb, and ub specify the type, lower bound, and upper
       
   531 *  bound, respectively, as follows:
       
   532 *
       
   533 *     Type           Bounds        Comments
       
   534 *     ------------------------------------------------------
       
   535 *     GLP_FR   -inf <  x <  +inf   Free variable
       
   536 *     GLP_LO     lb <= x <  +inf   Variable with lower bound
       
   537 *     GLP_UP   -inf <  x <=  ub    Variable with upper bound
       
   538 *     GLP_DB     lb <= x <=  ub    Double-bounded variable
       
   539 *     GLP_FX           x  =  lb    Fixed variable
       
   540 *
       
   541 *  where x is the auxiliary variable associated with i-th row.
       
   542 *
       
   543 *  If the row has no lower bound, the parameter lb is ignored. If the
       
   544 *  row has no upper bound, the parameter ub is ignored. If the row is
       
   545 *  an equality constraint (i.e. the corresponding auxiliary variable is
       
   546 *  of fixed type), only the parameter lb is used while the parameter ub
       
   547 *  is ignored. */
       
   548 
       
   549 void glp_set_row_bnds(glp_prob *lp, int i, int type, double lb,
       
   550       double ub)
       
   551 {     GLPROW *row;
       
   552       if (!(1 <= i && i <= lp->m))
       
   553          xerror("glp_set_row_bnds: i = %d; row number out of range\n",
       
   554             i);
       
   555       row = lp->row[i];
       
   556       row->type = type;
       
   557       switch (type)
       
   558       {  case GLP_FR:
       
   559             row->lb = row->ub = 0.0;
       
   560             if (row->stat != GLP_BS) row->stat = GLP_NF;
       
   561             break;
       
   562          case GLP_LO:
       
   563             row->lb = lb, row->ub = 0.0;
       
   564             if (row->stat != GLP_BS) row->stat = GLP_NL;
       
   565             break;
       
   566          case GLP_UP:
       
   567             row->lb = 0.0, row->ub = ub;
       
   568             if (row->stat != GLP_BS) row->stat = GLP_NU;
       
   569             break;
       
   570          case GLP_DB:
       
   571             row->lb = lb, row->ub = ub;
       
   572             if (!(row->stat == GLP_BS ||
       
   573                   row->stat == GLP_NL || row->stat == GLP_NU))
       
   574                row->stat = (fabs(lb) <= fabs(ub) ? GLP_NL : GLP_NU);
       
   575             break;
       
   576          case GLP_FX:
       
   577             row->lb = row->ub = lb;
       
   578             if (row->stat != GLP_BS) row->stat = GLP_NS;
       
   579             break;
       
   580          default:
       
   581             xerror("glp_set_row_bnds: i = %d; type = %d; invalid row ty"
       
   582                "pe\n", i, type);
       
   583       }
       
   584       return;
       
   585 }
       
   586 
       
   587 /***********************************************************************
       
   588 *  NAME
       
   589 *
       
   590 *  glp_set_col_bnds - set (change) column bounds
       
   591 *
       
   592 *  SYNOPSIS
       
   593 *
       
   594 *  void glp_set_col_bnds(glp_prob *lp, int j, int type, double lb,
       
   595 *     double ub);
       
   596 *
       
   597 *  DESCRIPTION
       
   598 *
       
   599 *  The routine glp_set_col_bnds sets (changes) the type and bounds of
       
   600 *  j-th column (structural variable) of the specified problem object.
       
   601 *
       
   602 *  Parameters type, lb, and ub specify the type, lower bound, and upper
       
   603 *  bound, respectively, as follows:
       
   604 *
       
   605 *     Type           Bounds        Comments
       
   606 *     ------------------------------------------------------
       
   607 *     GLP_FR   -inf <  x <  +inf   Free variable
       
   608 *     GLP_LO     lb <= x <  +inf   Variable with lower bound
       
   609 *     GLP_UP   -inf <  x <=  ub    Variable with upper bound
       
   610 *     GLP_DB     lb <= x <=  ub    Double-bounded variable
       
   611 *     GLP_FX           x  =  lb    Fixed variable
       
   612 *
       
   613 *  where x is the structural variable associated with j-th column.
       
   614 *
       
   615 *  If the column has no lower bound, the parameter lb is ignored. If the
       
   616 *  column has no upper bound, the parameter ub is ignored. If the column
       
   617 *  is of fixed type, only the parameter lb is used while the parameter
       
   618 *  ub is ignored. */
       
   619 
       
   620 void glp_set_col_bnds(glp_prob *lp, int j, int type, double lb,
       
   621       double ub)
       
   622 {     GLPCOL *col;
       
   623       if (!(1 <= j && j <= lp->n))
       
   624          xerror("glp_set_col_bnds: j = %d; column number out of range\n"
       
   625             , j);
       
   626       col = lp->col[j];
       
   627       col->type = type;
       
   628       switch (type)
       
   629       {  case GLP_FR:
       
   630             col->lb = col->ub = 0.0;
       
   631             if (col->stat != GLP_BS) col->stat = GLP_NF;
       
   632             break;
       
   633          case GLP_LO:
       
   634             col->lb = lb, col->ub = 0.0;
       
   635             if (col->stat != GLP_BS) col->stat = GLP_NL;
       
   636             break;
       
   637          case GLP_UP:
       
   638             col->lb = 0.0, col->ub = ub;
       
   639             if (col->stat != GLP_BS) col->stat = GLP_NU;
       
   640             break;
       
   641          case GLP_DB:
       
   642             col->lb = lb, col->ub = ub;
       
   643             if (!(col->stat == GLP_BS ||
       
   644                   col->stat == GLP_NL || col->stat == GLP_NU))
       
   645                col->stat = (fabs(lb) <= fabs(ub) ? GLP_NL : GLP_NU);
       
   646             break;
       
   647          case GLP_FX:
       
   648             col->lb = col->ub = lb;
       
   649             if (col->stat != GLP_BS) col->stat = GLP_NS;
       
   650             break;
       
   651          default:
       
   652             xerror("glp_set_col_bnds: j = %d; type = %d; invalid column"
       
   653                " type\n", j, type);
       
   654       }
       
   655       return;
       
   656 }
       
   657 
       
   658 /***********************************************************************
       
   659 *  NAME
       
   660 *
       
   661 *  glp_set_obj_coef - set (change) obj. coefficient or constant term
       
   662 *
       
   663 *  SYNOPSIS
       
   664 *
       
   665 *  void glp_set_obj_coef(glp_prob *lp, int j, double coef);
       
   666 *
       
   667 *  DESCRIPTION
       
   668 *
       
   669 *  The routine glp_set_obj_coef sets (changes) objective coefficient at
       
   670 *  j-th column (structural variable) of the specified problem object.
       
   671 *
       
   672 *  If the parameter j is 0, the routine sets (changes) the constant term
       
   673 *  ("shift") of the objective function. */
       
   674 
       
   675 void glp_set_obj_coef(glp_prob *lp, int j, double coef)
       
   676 {     glp_tree *tree = lp->tree;
       
   677       if (tree != NULL && tree->reason != 0)
       
   678          xerror("glp_set_obj_coef: operation not allowed\n");
       
   679       if (!(0 <= j && j <= lp->n))
       
   680          xerror("glp_set_obj_coef: j = %d; column number out of range\n"
       
   681             , j);
       
   682       if (j == 0)
       
   683          lp->c0 = coef;
       
   684       else
       
   685          lp->col[j]->coef = coef;
       
   686       return;
       
   687 }
       
   688 
       
   689 /***********************************************************************
       
   690 *  NAME
       
   691 *
       
   692 *  glp_set_mat_row - set (replace) row of the constraint matrix
       
   693 *
       
   694 *  SYNOPSIS
       
   695 *
       
   696 *  void glp_set_mat_row(glp_prob *lp, int i, int len, const int ind[],
       
   697 *     const double val[]);
       
   698 *
       
   699 *  DESCRIPTION
       
   700 *
       
   701 *  The routine glp_set_mat_row stores (replaces) the contents of i-th
       
   702 *  row of the constraint matrix of the specified problem object.
       
   703 *
       
   704 *  Column indices and numeric values of new row elements must be placed
       
   705 *  in locations ind[1], ..., ind[len] and val[1], ..., val[len], where
       
   706 *  0 <= len <= n is the new length of i-th row, n is the current number
       
   707 *  of columns in the problem object. Elements with identical column
       
   708 *  indices are not allowed. Zero elements are allowed, but they are not
       
   709 *  stored in the constraint matrix.
       
   710 *
       
   711 *  If the parameter len is zero, the parameters ind and/or val can be
       
   712 *  specified as NULL. */
       
   713 
       
   714 void glp_set_mat_row(glp_prob *lp, int i, int len, const int ind[],
       
   715       const double val[])
       
   716 {     glp_tree *tree = lp->tree;
       
   717       GLPROW *row;
       
   718       GLPCOL *col;
       
   719       GLPAIJ *aij, *next;
       
   720       int j, k;
       
   721       /* obtain pointer to i-th row */
       
   722       if (!(1 <= i && i <= lp->m))
       
   723          xerror("glp_set_mat_row: i = %d; row number out of range\n",
       
   724             i);
       
   725       row = lp->row[i];
       
   726       if (tree != NULL && tree->reason != 0)
       
   727       {  xassert(tree->curr != NULL);
       
   728          xassert(row->level == tree->curr->level);
       
   729       }
       
   730       /* remove all existing elements from i-th row */
       
   731       while (row->ptr != NULL)
       
   732       {  /* take next element in the row */
       
   733          aij = row->ptr;
       
   734          /* remove the element from the row list */
       
   735          row->ptr = aij->r_next;
       
   736          /* obtain pointer to corresponding column */
       
   737          col = aij->col;
       
   738          /* remove the element from the column list */
       
   739          if (aij->c_prev == NULL)
       
   740             col->ptr = aij->c_next;
       
   741          else
       
   742             aij->c_prev->c_next = aij->c_next;
       
   743          if (aij->c_next == NULL)
       
   744             ;
       
   745          else
       
   746             aij->c_next->c_prev = aij->c_prev;
       
   747          /* return the element to the memory pool */
       
   748          dmp_free_atom(lp->pool, aij, sizeof(GLPAIJ)), lp->nnz--;
       
   749          /* if the corresponding column is basic, invalidate the basis
       
   750             factorization */
       
   751          if (col->stat == GLP_BS) lp->valid = 0;
       
   752       }
       
   753       /* store new contents of i-th row */
       
   754       if (!(0 <= len && len <= lp->n))
       
   755          xerror("glp_set_mat_row: i = %d; len = %d; invalid row length "
       
   756             "\n", i, len);
       
   757       if (len > NNZ_MAX - lp->nnz)
       
   758          xerror("glp_set_mat_row: i = %d; len = %d; too many constraint"
       
   759             " coefficients\n", i, len);
       
   760       for (k = 1; k <= len; k++)
       
   761       {  /* take number j of corresponding column */
       
   762          j = ind[k];
       
   763          /* obtain pointer to j-th column */
       
   764          if (!(1 <= j && j <= lp->n))
       
   765             xerror("glp_set_mat_row: i = %d; ind[%d] = %d; column index"
       
   766                " out of range\n", i, k, j);
       
   767          col = lp->col[j];
       
   768          /* if there is element with the same column index, it can only
       
   769             be found in the beginning of j-th column list */
       
   770          if (col->ptr != NULL && col->ptr->row->i == i)
       
   771             xerror("glp_set_mat_row: i = %d; ind[%d] = %d; duplicate co"
       
   772                "lumn indices not allowed\n", i, k, j);
       
   773          /* create new element */
       
   774          aij = dmp_get_atom(lp->pool, sizeof(GLPAIJ)), lp->nnz++;
       
   775          aij->row = row;
       
   776          aij->col = col;
       
   777          aij->val = val[k];
       
   778          /* add the new element to the beginning of i-th row and j-th
       
   779             column lists */
       
   780          aij->r_prev = NULL;
       
   781          aij->r_next = row->ptr;
       
   782          aij->c_prev = NULL;
       
   783          aij->c_next = col->ptr;
       
   784          if (aij->r_next != NULL) aij->r_next->r_prev = aij;
       
   785          if (aij->c_next != NULL) aij->c_next->c_prev = aij;
       
   786          row->ptr = col->ptr = aij;
       
   787          /* if the corresponding column is basic, invalidate the basis
       
   788             factorization */
       
   789          if (col->stat == GLP_BS && aij->val != 0.0) lp->valid = 0;
       
   790       }
       
   791       /* remove zero elements from i-th row */
       
   792       for (aij = row->ptr; aij != NULL; aij = next)
       
   793       {  next = aij->r_next;
       
   794          if (aij->val == 0.0)
       
   795          {  /* remove the element from the row list */
       
   796             if (aij->r_prev == NULL)
       
   797                row->ptr = next;
       
   798             else
       
   799                aij->r_prev->r_next = next;
       
   800             if (next == NULL)
       
   801                ;
       
   802             else
       
   803                next->r_prev = aij->r_prev;
       
   804             /* remove the element from the column list */
       
   805             xassert(aij->c_prev == NULL);
       
   806             aij->col->ptr = aij->c_next;
       
   807             if (aij->c_next != NULL) aij->c_next->c_prev = NULL;
       
   808             /* return the element to the memory pool */
       
   809             dmp_free_atom(lp->pool, aij, sizeof(GLPAIJ)), lp->nnz--;
       
   810          }
       
   811       }
       
   812       return;
       
   813 }
       
   814 
       
   815 /***********************************************************************
       
   816 *  NAME
       
   817 *
       
   818 *  glp_set_mat_col - set (replace) column of the constraint matrix
       
   819 *
       
   820 *  SYNOPSIS
       
   821 *
       
   822 *  void glp_set_mat_col(glp_prob *lp, int j, int len, const int ind[],
       
   823 *     const double val[]);
       
   824 *
       
   825 *  DESCRIPTION
       
   826 *
       
   827 *  The routine glp_set_mat_col stores (replaces) the contents of j-th
       
   828 *  column of the constraint matrix of the specified problem object.
       
   829 *
       
   830 *  Row indices and numeric values of new column elements must be placed
       
   831 *  in locations ind[1], ..., ind[len] and val[1], ..., val[len], where
       
   832 *  0 <= len <= m is the new length of j-th column, m is the current
       
   833 *  number of rows in the problem object. Elements with identical column
       
   834 *  indices are not allowed. Zero elements are allowed, but they are not
       
   835 *  stored in the constraint matrix.
       
   836 *
       
   837 *  If the parameter len is zero, the parameters ind and/or val can be
       
   838 *  specified as NULL. */
       
   839 
       
   840 void glp_set_mat_col(glp_prob *lp, int j, int len, const int ind[],
       
   841       const double val[])
       
   842 {     glp_tree *tree = lp->tree;
       
   843       GLPROW *row;
       
   844       GLPCOL *col;
       
   845       GLPAIJ *aij, *next;
       
   846       int i, k;
       
   847       if (tree != NULL && tree->reason != 0)
       
   848          xerror("glp_set_mat_col: operation not allowed\n");
       
   849       /* obtain pointer to j-th column */
       
   850       if (!(1 <= j && j <= lp->n))
       
   851          xerror("glp_set_mat_col: j = %d; column number out of range\n",
       
   852             j);
       
   853       col = lp->col[j];
       
   854       /* remove all existing elements from j-th column */
       
   855       while (col->ptr != NULL)
       
   856       {  /* take next element in the column */
       
   857          aij = col->ptr;
       
   858          /* remove the element from the column list */
       
   859          col->ptr = aij->c_next;
       
   860          /* obtain pointer to corresponding row */
       
   861          row = aij->row;
       
   862          /* remove the element from the row list */
       
   863          if (aij->r_prev == NULL)
       
   864             row->ptr = aij->r_next;
       
   865          else
       
   866             aij->r_prev->r_next = aij->r_next;
       
   867          if (aij->r_next == NULL)
       
   868             ;
       
   869          else
       
   870             aij->r_next->r_prev = aij->r_prev;
       
   871          /* return the element to the memory pool */
       
   872          dmp_free_atom(lp->pool, aij, sizeof(GLPAIJ)), lp->nnz--;
       
   873       }
       
   874       /* store new contents of j-th column */
       
   875       if (!(0 <= len && len <= lp->m))
       
   876          xerror("glp_set_mat_col: j = %d; len = %d; invalid column leng"
       
   877             "th\n", j, len);
       
   878       if (len > NNZ_MAX - lp->nnz)
       
   879          xerror("glp_set_mat_col: j = %d; len = %d; too many constraint"
       
   880             " coefficients\n", j, len);
       
   881       for (k = 1; k <= len; k++)
       
   882       {  /* take number i of corresponding row */
       
   883          i = ind[k];
       
   884          /* obtain pointer to i-th row */
       
   885          if (!(1 <= i && i <= lp->m))
       
   886             xerror("glp_set_mat_col: j = %d; ind[%d] = %d; row index ou"
       
   887                "t of range\n", j, k, i);
       
   888          row = lp->row[i];
       
   889          /* if there is element with the same row index, it can only be
       
   890             found in the beginning of i-th row list */
       
   891          if (row->ptr != NULL && row->ptr->col->j == j)
       
   892             xerror("glp_set_mat_col: j = %d; ind[%d] = %d; duplicate ro"
       
   893                "w indices not allowed\n", j, k, i);
       
   894          /* create new element */
       
   895          aij = dmp_get_atom(lp->pool, sizeof(GLPAIJ)), lp->nnz++;
       
   896          aij->row = row;
       
   897          aij->col = col;
       
   898          aij->val = val[k];
       
   899          /* add the new element to the beginning of i-th row and j-th
       
   900             column lists */
       
   901          aij->r_prev = NULL;
       
   902          aij->r_next = row->ptr;
       
   903          aij->c_prev = NULL;
       
   904          aij->c_next = col->ptr;
       
   905          if (aij->r_next != NULL) aij->r_next->r_prev = aij;
       
   906          if (aij->c_next != NULL) aij->c_next->c_prev = aij;
       
   907          row->ptr = col->ptr = aij;
       
   908       }
       
   909       /* remove zero elements from j-th column */
       
   910       for (aij = col->ptr; aij != NULL; aij = next)
       
   911       {  next = aij->c_next;
       
   912          if (aij->val == 0.0)
       
   913          {  /* remove the element from the row list */
       
   914             xassert(aij->r_prev == NULL);
       
   915             aij->row->ptr = aij->r_next;
       
   916             if (aij->r_next != NULL) aij->r_next->r_prev = NULL;
       
   917             /* remove the element from the column list */
       
   918             if (aij->c_prev == NULL)
       
   919                col->ptr = next;
       
   920             else
       
   921                aij->c_prev->c_next = next;
       
   922             if (next == NULL)
       
   923                ;
       
   924             else
       
   925                next->c_prev = aij->c_prev;
       
   926             /* return the element to the memory pool */
       
   927             dmp_free_atom(lp->pool, aij, sizeof(GLPAIJ)), lp->nnz--;
       
   928          }
       
   929       }
       
   930       /* if j-th column is basic, invalidate the basis factorization */
       
   931       if (col->stat == GLP_BS) lp->valid = 0;
       
   932       return;
       
   933 }
       
   934 
       
   935 /***********************************************************************
       
   936 *  NAME
       
   937 *
       
   938 *  glp_load_matrix - load (replace) the whole constraint matrix
       
   939 *
       
   940 *  SYNOPSIS
       
   941 *
       
   942 *  void glp_load_matrix(glp_prob *lp, int ne, const int ia[],
       
   943 *     const int ja[], const double ar[]);
       
   944 *
       
   945 *  DESCRIPTION
       
   946 *
       
   947 *  The routine glp_load_matrix loads the constraint matrix passed in
       
   948 *  the arrays ia, ja, and ar into the specified problem object. Before
       
   949 *  loading the current contents of the constraint matrix is destroyed.
       
   950 *
       
   951 *  Constraint coefficients (elements of the constraint matrix) must be
       
   952 *  specified as triplets (ia[k], ja[k], ar[k]) for k = 1, ..., ne,
       
   953 *  where ia[k] is the row index, ja[k] is the column index, ar[k] is a
       
   954 *  numeric value of corresponding constraint coefficient. The parameter
       
   955 *  ne specifies the total number of (non-zero) elements in the matrix
       
   956 *  to be loaded. Coefficients with identical indices are not allowed.
       
   957 *  Zero coefficients are allowed, however, they are not stored in the
       
   958 *  constraint matrix.
       
   959 *
       
   960 *  If the parameter ne is zero, the parameters ia, ja, and ar can be
       
   961 *  specified as NULL. */
       
   962 
       
   963 void glp_load_matrix(glp_prob *lp, int ne, const int ia[],
       
   964       const int ja[], const double ar[])
       
   965 {     glp_tree *tree = lp->tree;
       
   966       GLPROW *row;
       
   967       GLPCOL *col;
       
   968       GLPAIJ *aij, *next;
       
   969       int i, j, k;
       
   970       if (tree != NULL && tree->reason != 0)
       
   971          xerror("glp_load_matrix: operation not allowed\n");
       
   972       /* clear the constraint matrix */
       
   973       for (i = 1; i <= lp->m; i++)
       
   974       {  row = lp->row[i];
       
   975          while (row->ptr != NULL)
       
   976          {  aij = row->ptr;
       
   977             row->ptr = aij->r_next;
       
   978             dmp_free_atom(lp->pool, aij, sizeof(GLPAIJ)), lp->nnz--;
       
   979          }
       
   980       }
       
   981       xassert(lp->nnz == 0);
       
   982       for (j = 1; j <= lp->n; j++) lp->col[j]->ptr = NULL;
       
   983       /* load the new contents of the constraint matrix and build its
       
   984          row lists */
       
   985       if (ne < 0)
       
   986          xerror("glp_load_matrix: ne = %d; invalid number of constraint"
       
   987             " coefficients\n", ne);
       
   988       if (ne > NNZ_MAX)
       
   989          xerror("glp_load_matrix: ne = %d; too many constraint coeffici"
       
   990             "ents\n", ne);
       
   991       for (k = 1; k <= ne; k++)
       
   992       {  /* take indices of new element */
       
   993          i = ia[k], j = ja[k];
       
   994          /* obtain pointer to i-th row */
       
   995          if (!(1 <= i && i <= lp->m))
       
   996             xerror("glp_load_matrix: ia[%d] = %d; row index out of rang"
       
   997                "e\n", k, i);
       
   998          row = lp->row[i];
       
   999          /* obtain pointer to j-th column */
       
  1000          if (!(1 <= j && j <= lp->n))
       
  1001             xerror("glp_load_matrix: ja[%d] = %d; column index out of r"
       
  1002                "ange\n", k, j);
       
  1003          col = lp->col[j];
       
  1004          /* create new element */
       
  1005          aij = dmp_get_atom(lp->pool, sizeof(GLPAIJ)), lp->nnz++;
       
  1006          aij->row = row;
       
  1007          aij->col = col;
       
  1008          aij->val = ar[k];
       
  1009          /* add the new element to the beginning of i-th row list */
       
  1010          aij->r_prev = NULL;
       
  1011          aij->r_next = row->ptr;
       
  1012          if (aij->r_next != NULL) aij->r_next->r_prev = aij;
       
  1013          row->ptr = aij;
       
  1014       }
       
  1015       xassert(lp->nnz == ne);
       
  1016       /* build column lists of the constraint matrix and check elements
       
  1017          with identical indices */
       
  1018       for (i = 1; i <= lp->m; i++)
       
  1019       {  for (aij = lp->row[i]->ptr; aij != NULL; aij = aij->r_next)
       
  1020          {  /* obtain pointer to corresponding column */
       
  1021             col = aij->col;
       
  1022             /* if there is element with identical indices, it can only
       
  1023                be found in the beginning of j-th column list */
       
  1024             if (col->ptr != NULL && col->ptr->row->i == i)
       
  1025             {  for (k = 1; k <= ne; k++)
       
  1026                   if (ia[k] == i && ja[k] == col->j) break;
       
  1027                xerror("glp_load_mat: ia[%d] = %d; ja[%d] = %d; duplicat"
       
  1028                   "e indices not allowed\n", k, i, k, col->j);
       
  1029             }
       
  1030             /* add the element to the beginning of j-th column list */
       
  1031             aij->c_prev = NULL;
       
  1032             aij->c_next = col->ptr;
       
  1033             if (aij->c_next != NULL) aij->c_next->c_prev = aij;
       
  1034             col->ptr = aij;
       
  1035          }
       
  1036       }
       
  1037       /* remove zero elements from the constraint matrix */
       
  1038       for (i = 1; i <= lp->m; i++)
       
  1039       {  row = lp->row[i];
       
  1040          for (aij = row->ptr; aij != NULL; aij = next)
       
  1041          {  next = aij->r_next;
       
  1042             if (aij->val == 0.0)
       
  1043             {  /* remove the element from the row list */
       
  1044                if (aij->r_prev == NULL)
       
  1045                   row->ptr = next;
       
  1046                else
       
  1047                   aij->r_prev->r_next = next;
       
  1048                if (next == NULL)
       
  1049                   ;
       
  1050                else
       
  1051                   next->r_prev = aij->r_prev;
       
  1052                /* remove the element from the column list */
       
  1053                if (aij->c_prev == NULL)
       
  1054                   aij->col->ptr = aij->c_next;
       
  1055                else
       
  1056                   aij->c_prev->c_next = aij->c_next;
       
  1057                if (aij->c_next == NULL)
       
  1058                   ;
       
  1059                else
       
  1060                   aij->c_next->c_prev = aij->c_prev;
       
  1061                /* return the element to the memory pool */
       
  1062                dmp_free_atom(lp->pool, aij, sizeof(GLPAIJ)), lp->nnz--;
       
  1063             }
       
  1064          }
       
  1065       }
       
  1066       /* invalidate the basis factorization */
       
  1067       lp->valid = 0;
       
  1068       return;
       
  1069 }
       
  1070 
       
  1071 /***********************************************************************
       
  1072 *  NAME
       
  1073 *
       
  1074 *  glp_check_dup - check for duplicate elements in sparse matrix
       
  1075 *
       
  1076 *  SYNOPSIS
       
  1077 *
       
  1078 *  int glp_check_dup(int m, int n, int ne, const int ia[],
       
  1079 *     const int ja[]);
       
  1080 *
       
  1081 *  DESCRIPTION
       
  1082 *
       
  1083 *  The routine glp_check_dup checks for duplicate elements (that is,
       
  1084 *  elements with identical indices) in a sparse matrix specified in the
       
  1085 *  coordinate format.
       
  1086 *
       
  1087 *  The parameters m and n specifies, respectively, the number of rows
       
  1088 *  and columns in the matrix, m >= 0, n >= 0.
       
  1089 *
       
  1090 *  The parameter ne specifies the number of (structurally) non-zero
       
  1091 *  elements in the matrix, ne >= 0.
       
  1092 *
       
  1093 *  Elements of the matrix are specified as doublets (ia[k],ja[k]) for
       
  1094 *  k = 1,...,ne, where ia[k] is a row index, ja[k] is a column index.
       
  1095 *
       
  1096 *  The routine glp_check_dup can be used prior to a call to the routine
       
  1097 *  glp_load_matrix to check that the constraint matrix to be loaded has
       
  1098 *  no duplicate elements.
       
  1099 *
       
  1100 *  RETURNS
       
  1101 *
       
  1102 *  The routine glp_check_dup returns one of the following values:
       
  1103 *
       
  1104 *   0 - the matrix has no duplicate elements;
       
  1105 *
       
  1106 *  -k - indices ia[k] or/and ja[k] are out of range;
       
  1107 *
       
  1108 *  +k - element (ia[k],ja[k]) is duplicate. */
       
  1109 
       
  1110 int glp_check_dup(int m, int n, int ne, const int ia[], const int ja[])
       
  1111 {     int i, j, k, *ptr, *next, ret;
       
  1112       char *flag;
       
  1113       if (m < 0)
       
  1114          xerror("glp_check_dup: m = %d; invalid parameter\n");
       
  1115       if (n < 0)
       
  1116          xerror("glp_check_dup: n = %d; invalid parameter\n");
       
  1117       if (ne < 0)
       
  1118          xerror("glp_check_dup: ne = %d; invalid parameter\n");
       
  1119       if (ne > 0 && ia == NULL)
       
  1120          xerror("glp_check_dup: ia = %p; invalid parameter\n", ia);
       
  1121       if (ne > 0 && ja == NULL)
       
  1122          xerror("glp_check_dup: ja = %p; invalid parameter\n", ja);
       
  1123       for (k = 1; k <= ne; k++)
       
  1124       {  i = ia[k], j = ja[k];
       
  1125          if (!(1 <= i && i <= m && 1 <= j && j <= n))
       
  1126          {  ret = -k;
       
  1127             goto done;
       
  1128          }
       
  1129       }
       
  1130       if (m == 0 || n == 0)
       
  1131       {  ret = 0;
       
  1132          goto done;
       
  1133       }
       
  1134       /* allocate working arrays */
       
  1135       ptr = xcalloc(1+m, sizeof(int));
       
  1136       next = xcalloc(1+ne, sizeof(int));
       
  1137       flag = xcalloc(1+n, sizeof(char));
       
  1138       /* build row lists */
       
  1139       for (i = 1; i <= m; i++)
       
  1140          ptr[i] = 0;
       
  1141       for (k = 1; k <= ne; k++)
       
  1142       {  i = ia[k];
       
  1143          next[k] = ptr[i];
       
  1144          ptr[i] = k;
       
  1145       }
       
  1146       /* clear column flags */
       
  1147       for (j = 1; j <= n; j++)
       
  1148          flag[j] = 0;
       
  1149       /* check for duplicate elements */
       
  1150       for (i = 1; i <= m; i++)
       
  1151       {  for (k = ptr[i]; k != 0; k = next[k])
       
  1152          {  j = ja[k];
       
  1153             if (flag[j])
       
  1154             {  /* find first element (i,j) */
       
  1155                for (k = 1; k <= ne; k++)
       
  1156                   if (ia[k] == i && ja[k] == j) break;
       
  1157                xassert(k <= ne);
       
  1158                /* find next (duplicate) element (i,j) */
       
  1159                for (k++; k <= ne; k++)
       
  1160                   if (ia[k] == i && ja[k] == j) break;
       
  1161                xassert(k <= ne);
       
  1162                ret = +k;
       
  1163                goto skip;
       
  1164             }
       
  1165             flag[j] = 1;
       
  1166          }
       
  1167          /* clear column flags */
       
  1168          for (k = ptr[i]; k != 0; k = next[k])
       
  1169             flag[ja[k]] = 0;
       
  1170       }
       
  1171       /* no duplicate element found */
       
  1172       ret = 0;
       
  1173 skip: /* free working arrays */
       
  1174       xfree(ptr);
       
  1175       xfree(next);
       
  1176       xfree(flag);
       
  1177 done: return ret;
       
  1178 }
       
  1179 
       
  1180 /***********************************************************************
       
  1181 *  NAME
       
  1182 *
       
  1183 *  glp_sort_matrix - sort elements of the constraint matrix
       
  1184 *
       
  1185 *  SYNOPSIS
       
  1186 *
       
  1187 *  void glp_sort_matrix(glp_prob *P);
       
  1188 *
       
  1189 *  DESCRIPTION
       
  1190 *
       
  1191 *  The routine glp_sort_matrix sorts elements of the constraint matrix
       
  1192 *  rebuilding its row and column linked lists. On exit from the routine
       
  1193 *  the constraint matrix is not changed, however, elements in the row
       
  1194 *  linked lists become ordered by ascending column indices, and the
       
  1195 *  elements in the column linked lists become ordered by ascending row
       
  1196 *  indices. */
       
  1197 
       
  1198 void glp_sort_matrix(glp_prob *P)
       
  1199 {     GLPAIJ *aij;
       
  1200       int i, j;
       
  1201       if (P == NULL || P->magic != GLP_PROB_MAGIC)
       
  1202          xerror("glp_sort_matrix: P = %p; invalid problem object\n",
       
  1203             P);
       
  1204       /* rebuild row linked lists */
       
  1205       for (i = P->m; i >= 1; i--)
       
  1206          P->row[i]->ptr = NULL;
       
  1207       for (j = P->n; j >= 1; j--)
       
  1208       {  for (aij = P->col[j]->ptr; aij != NULL; aij = aij->c_next)
       
  1209          {  i = aij->row->i;
       
  1210             aij->r_prev = NULL;
       
  1211             aij->r_next = P->row[i]->ptr;
       
  1212             if (aij->r_next != NULL) aij->r_next->r_prev = aij;
       
  1213             P->row[i]->ptr = aij;
       
  1214          }
       
  1215       }
       
  1216       /* rebuild column linked lists */
       
  1217       for (j = P->n; j >= 1; j--)
       
  1218          P->col[j]->ptr = NULL;
       
  1219       for (i = P->m; i >= 1; i--)
       
  1220       {  for (aij = P->row[i]->ptr; aij != NULL; aij = aij->r_next)
       
  1221          {  j = aij->col->j;
       
  1222             aij->c_prev = NULL;
       
  1223             aij->c_next = P->col[j]->ptr;
       
  1224             if (aij->c_next != NULL) aij->c_next->c_prev = aij;
       
  1225             P->col[j]->ptr = aij;
       
  1226          }
       
  1227       }
       
  1228       return;
       
  1229 }
       
  1230 
       
  1231 /***********************************************************************
       
  1232 *  NAME
       
  1233 *
       
  1234 *  glp_del_rows - delete rows from problem object
       
  1235 *
       
  1236 *  SYNOPSIS
       
  1237 *
       
  1238 *  void glp_del_rows(glp_prob *lp, int nrs, const int num[]);
       
  1239 *
       
  1240 *  DESCRIPTION
       
  1241 *
       
  1242 *  The routine glp_del_rows deletes rows from the specified problem
       
  1243 *  object. Ordinal numbers of rows to be deleted should be placed in
       
  1244 *  locations num[1], ..., num[nrs], where nrs > 0.
       
  1245 *
       
  1246 *  Note that deleting rows involves changing ordinal numbers of other
       
  1247 *  rows remaining in the problem object. New ordinal numbers of the
       
  1248 *  remaining rows are assigned under the assumption that the original
       
  1249 *  order of rows is not changed. */
       
  1250 
       
  1251 void glp_del_rows(glp_prob *lp, int nrs, const int num[])
       
  1252 {     glp_tree *tree = lp->tree;
       
  1253       GLPROW *row;
       
  1254       int i, k, m_new;
       
  1255       /* mark rows to be deleted */
       
  1256       if (!(1 <= nrs && nrs <= lp->m))
       
  1257          xerror("glp_del_rows: nrs = %d; invalid number of rows\n",
       
  1258             nrs);
       
  1259       for (k = 1; k <= nrs; k++)
       
  1260       {  /* take the number of row to be deleted */
       
  1261          i = num[k];
       
  1262          /* obtain pointer to i-th row */
       
  1263          if (!(1 <= i && i <= lp->m))
       
  1264             xerror("glp_del_rows: num[%d] = %d; row number out of range"
       
  1265                "\n", k, i);
       
  1266          row = lp->row[i];
       
  1267          if (tree != NULL && tree->reason != 0)
       
  1268          {  if (!(tree->reason == GLP_IROWGEN ||
       
  1269                   tree->reason == GLP_ICUTGEN))
       
  1270                xerror("glp_del_rows: operation not allowed\n");
       
  1271             xassert(tree->curr != NULL);
       
  1272             if (row->level != tree->curr->level)
       
  1273                xerror("glp_del_rows: num[%d] = %d; invalid attempt to d"
       
  1274                   "elete row created not in current subproblem\n", k,i);
       
  1275             if (row->stat != GLP_BS)
       
  1276                xerror("glp_del_rows: num[%d] = %d; invalid attempt to d"
       
  1277                   "elete active row (constraint)\n", k, i);
       
  1278             tree->reinv = 1;
       
  1279          }
       
  1280          /* check that the row is not marked yet */
       
  1281          if (row->i == 0)
       
  1282             xerror("glp_del_rows: num[%d] = %d; duplicate row numbers n"
       
  1283                "ot allowed\n", k, i);
       
  1284          /* erase symbolic name assigned to the row */
       
  1285          glp_set_row_name(lp, i, NULL);
       
  1286          xassert(row->node == NULL);
       
  1287          /* erase corresponding row of the constraint matrix */
       
  1288          glp_set_mat_row(lp, i, 0, NULL, NULL);
       
  1289          xassert(row->ptr == NULL);
       
  1290          /* mark the row to be deleted */
       
  1291          row->i = 0;
       
  1292       }
       
  1293       /* delete all marked rows from the row list */
       
  1294       m_new = 0;
       
  1295       for (i = 1; i <= lp->m; i++)
       
  1296       {  /* obtain pointer to i-th row */
       
  1297          row = lp->row[i];
       
  1298          /* check if the row is marked */
       
  1299          if (row->i == 0)
       
  1300          {  /* it is marked, delete it */
       
  1301             dmp_free_atom(lp->pool, row, sizeof(GLPROW));
       
  1302          }
       
  1303          else
       
  1304          {  /* it is not marked; keep it */
       
  1305             row->i = ++m_new;
       
  1306             lp->row[row->i] = row;
       
  1307          }
       
  1308       }
       
  1309       /* set new number of rows */
       
  1310       lp->m = m_new;
       
  1311       /* invalidate the basis factorization */
       
  1312       lp->valid = 0;
       
  1313       return;
       
  1314 }
       
  1315 
       
  1316 /***********************************************************************
       
  1317 *  NAME
       
  1318 *
       
  1319 *  glp_del_cols - delete columns from problem object
       
  1320 *
       
  1321 *  SYNOPSIS
       
  1322 *
       
  1323 *  void glp_del_cols(glp_prob *lp, int ncs, const int num[]);
       
  1324 *
       
  1325 *  DESCRIPTION
       
  1326 *
       
  1327 *  The routine glp_del_cols deletes columns from the specified problem
       
  1328 *  object. Ordinal numbers of columns to be deleted should be placed in
       
  1329 *  locations num[1], ..., num[ncs], where ncs > 0.
       
  1330 *
       
  1331 *  Note that deleting columns involves changing ordinal numbers of
       
  1332 *  other columns remaining in the problem object. New ordinal numbers
       
  1333 *  of the remaining columns are assigned under the assumption that the
       
  1334 *  original order of columns is not changed. */
       
  1335 
       
  1336 void glp_del_cols(glp_prob *lp, int ncs, const int num[])
       
  1337 {     glp_tree *tree = lp->tree;
       
  1338       GLPCOL *col;
       
  1339       int j, k, n_new;
       
  1340       if (tree != NULL && tree->reason != 0)
       
  1341          xerror("glp_del_cols: operation not allowed\n");
       
  1342       /* mark columns to be deleted */
       
  1343       if (!(1 <= ncs && ncs <= lp->n))
       
  1344          xerror("glp_del_cols: ncs = %d; invalid number of columns\n",
       
  1345             ncs);
       
  1346       for (k = 1; k <= ncs; k++)
       
  1347       {  /* take the number of column to be deleted */
       
  1348          j = num[k];
       
  1349          /* obtain pointer to j-th column */
       
  1350          if (!(1 <= j && j <= lp->n))
       
  1351             xerror("glp_del_cols: num[%d] = %d; column number out of ra"
       
  1352                "nge", k, j);
       
  1353          col = lp->col[j];
       
  1354          /* check that the column is not marked yet */
       
  1355          if (col->j == 0)
       
  1356             xerror("glp_del_cols: num[%d] = %d; duplicate column number"
       
  1357                "s not allowed\n", k, j);
       
  1358          /* erase symbolic name assigned to the column */
       
  1359          glp_set_col_name(lp, j, NULL);
       
  1360          xassert(col->node == NULL);
       
  1361          /* erase corresponding column of the constraint matrix */
       
  1362          glp_set_mat_col(lp, j, 0, NULL, NULL);
       
  1363          xassert(col->ptr == NULL);
       
  1364          /* mark the column to be deleted */
       
  1365          col->j = 0;
       
  1366          /* if it is basic, invalidate the basis factorization */
       
  1367          if (col->stat == GLP_BS) lp->valid = 0;
       
  1368       }
       
  1369       /* delete all marked columns from the column list */
       
  1370       n_new = 0;
       
  1371       for (j = 1; j <= lp->n; j++)
       
  1372       {  /* obtain pointer to j-th column */
       
  1373          col = lp->col[j];
       
  1374          /* check if the column is marked */
       
  1375          if (col->j == 0)
       
  1376          {  /* it is marked; delete it */
       
  1377             dmp_free_atom(lp->pool, col, sizeof(GLPCOL));
       
  1378          }
       
  1379          else
       
  1380          {  /* it is not marked; keep it */
       
  1381             col->j = ++n_new;
       
  1382             lp->col[col->j] = col;
       
  1383          }
       
  1384       }
       
  1385       /* set new number of columns */
       
  1386       lp->n = n_new;
       
  1387       /* if the basis header is still valid, adjust it */
       
  1388       if (lp->valid)
       
  1389       {  int m = lp->m;
       
  1390          int *head = lp->head;
       
  1391          for (j = 1; j <= n_new; j++)
       
  1392          {  k = lp->col[j]->bind;
       
  1393             if (k != 0)
       
  1394             {  xassert(1 <= k && k <= m);
       
  1395                head[k] = m + j;
       
  1396             }
       
  1397          }
       
  1398       }
       
  1399       return;
       
  1400 }
       
  1401 
       
  1402 /***********************************************************************
       
  1403 *  NAME
       
  1404 *
       
  1405 *  glp_copy_prob - copy problem object content
       
  1406 *
       
  1407 *  SYNOPSIS
       
  1408 *
       
  1409 *  void glp_copy_prob(glp_prob *dest, glp_prob *prob, int names);
       
  1410 *
       
  1411 *  DESCRIPTION
       
  1412 *
       
  1413 *  The routine glp_copy_prob copies the content of the problem object
       
  1414 *  prob to the problem object dest.
       
  1415 *
       
  1416 *  The parameter names is a flag. If it is non-zero, the routine also
       
  1417 *  copies all symbolic names; otherwise, if it is zero, symbolic names
       
  1418 *  are not copied. */
       
  1419 
       
  1420 void glp_copy_prob(glp_prob *dest, glp_prob *prob, int names)
       
  1421 {     glp_tree *tree = dest->tree;
       
  1422       glp_bfcp bfcp;
       
  1423       int i, j, len, *ind;
       
  1424       double *val;
       
  1425       if (tree != NULL && tree->reason != 0)
       
  1426          xerror("glp_copy_prob: operation not allowed\n");
       
  1427       if (dest == prob)
       
  1428          xerror("glp_copy_prob: copying problem object to itself not al"
       
  1429             "lowed\n");
       
  1430       if (!(names == GLP_ON || names == GLP_OFF))
       
  1431          xerror("glp_copy_prob: names = %d; invalid parameter\n",
       
  1432             names);
       
  1433       glp_erase_prob(dest);
       
  1434       if (names && prob->name != NULL)
       
  1435          glp_set_prob_name(dest, prob->name);
       
  1436       if (names && prob->obj != NULL)
       
  1437          glp_set_obj_name(dest, prob->obj);
       
  1438       dest->dir = prob->dir;
       
  1439       dest->c0 = prob->c0;
       
  1440       if (prob->m > 0)
       
  1441          glp_add_rows(dest, prob->m);
       
  1442       if (prob->n > 0)
       
  1443          glp_add_cols(dest, prob->n);
       
  1444       glp_get_bfcp(prob, &bfcp);
       
  1445       glp_set_bfcp(dest, &bfcp);
       
  1446       dest->pbs_stat = prob->pbs_stat;
       
  1447       dest->dbs_stat = prob->dbs_stat;
       
  1448       dest->obj_val = prob->obj_val;
       
  1449       dest->some = prob->some;
       
  1450       dest->ipt_stat = prob->ipt_stat;
       
  1451       dest->ipt_obj = prob->ipt_obj;
       
  1452       dest->mip_stat = prob->mip_stat;
       
  1453       dest->mip_obj = prob->mip_obj;
       
  1454       for (i = 1; i <= prob->m; i++)
       
  1455       {  GLPROW *to = dest->row[i];
       
  1456          GLPROW *from = prob->row[i];
       
  1457          if (names && from->name != NULL)
       
  1458             glp_set_row_name(dest, i, from->name);
       
  1459          to->type = from->type;
       
  1460          to->lb = from->lb;
       
  1461          to->ub = from->ub;
       
  1462          to->rii = from->rii;
       
  1463          to->stat = from->stat;
       
  1464          to->prim = from->prim;
       
  1465          to->dual = from->dual;
       
  1466          to->pval = from->pval;
       
  1467          to->dval = from->dval;
       
  1468          to->mipx = from->mipx;
       
  1469       }
       
  1470       ind = xcalloc(1+prob->m, sizeof(int));
       
  1471       val = xcalloc(1+prob->m, sizeof(double));
       
  1472       for (j = 1; j <= prob->n; j++)
       
  1473       {  GLPCOL *to = dest->col[j];
       
  1474          GLPCOL *from = prob->col[j];
       
  1475          if (names && from->name != NULL)
       
  1476             glp_set_col_name(dest, j, from->name);
       
  1477          to->kind = from->kind;
       
  1478          to->type = from->type;
       
  1479          to->lb = from->lb;
       
  1480          to->ub = from->ub;
       
  1481          to->coef = from->coef;
       
  1482          len = glp_get_mat_col(prob, j, ind, val);
       
  1483          glp_set_mat_col(dest, j, len, ind, val);
       
  1484          to->sjj = from->sjj;
       
  1485          to->stat = from->stat;
       
  1486          to->prim = from->prim;
       
  1487          to->dual = from->dual;
       
  1488          to->pval = from->pval;
       
  1489          to->dval = from->dval;
       
  1490          to->mipx = from->mipx;
       
  1491       }
       
  1492       xfree(ind);
       
  1493       xfree(val);
       
  1494       return;
       
  1495 }
       
  1496 
       
  1497 /***********************************************************************
       
  1498 *  NAME
       
  1499 *
       
  1500 *  glp_erase_prob - erase problem object content
       
  1501 *
       
  1502 *  SYNOPSIS
       
  1503 *
       
  1504 *  void glp_erase_prob(glp_prob *lp);
       
  1505 *
       
  1506 *  DESCRIPTION
       
  1507 *
       
  1508 *  The routine glp_erase_prob erases the content of the specified
       
  1509 *  problem object. The effect of this operation is the same as if the
       
  1510 *  problem object would be deleted with the routine glp_delete_prob and
       
  1511 *  then created anew with the routine glp_create_prob, with exception
       
  1512 *  that the handle (pointer) to the problem object remains valid. */
       
  1513 
       
  1514 static void delete_prob(glp_prob *lp);
       
  1515 
       
  1516 void glp_erase_prob(glp_prob *lp)
       
  1517 {     glp_tree *tree = lp->tree;
       
  1518       if (tree != NULL && tree->reason != 0)
       
  1519          xerror("glp_erase_prob: operation not allowed\n");
       
  1520       delete_prob(lp);
       
  1521       create_prob(lp);
       
  1522       return;
       
  1523 }
       
  1524 
       
  1525 /***********************************************************************
       
  1526 *  NAME
       
  1527 *
       
  1528 *  glp_delete_prob - delete problem object
       
  1529 *
       
  1530 *  SYNOPSIS
       
  1531 *
       
  1532 *  void glp_delete_prob(glp_prob *lp);
       
  1533 *
       
  1534 *  DESCRIPTION
       
  1535 *
       
  1536 *  The routine glp_delete_prob deletes the specified problem object and
       
  1537 *  frees all the memory allocated to it. */
       
  1538 
       
  1539 static void delete_prob(glp_prob *lp)
       
  1540 {     lp->magic = 0x3F3F3F3F;
       
  1541       dmp_delete_pool(lp->pool);
       
  1542 #if 0 /* 17/XI-2009 */
       
  1543       xfree(lp->cps);
       
  1544 #else
       
  1545       if (lp->parms != NULL) xfree(lp->parms);
       
  1546 #endif
       
  1547       xassert(lp->tree == NULL);
       
  1548 #if 0
       
  1549       if (lp->cwa != NULL) xfree(lp->cwa);
       
  1550 #endif
       
  1551       xfree(lp->row);
       
  1552       xfree(lp->col);
       
  1553       if (lp->r_tree != NULL) avl_delete_tree(lp->r_tree);
       
  1554       if (lp->c_tree != NULL) avl_delete_tree(lp->c_tree);
       
  1555       xfree(lp->head);
       
  1556       if (lp->bfcp != NULL) xfree(lp->bfcp);
       
  1557       if (lp->bfd != NULL) bfd_delete_it(lp->bfd);
       
  1558       return;
       
  1559 }
       
  1560 
       
  1561 void glp_delete_prob(glp_prob *lp)
       
  1562 {     glp_tree *tree = lp->tree;
       
  1563       if (tree != NULL && tree->reason != 0)
       
  1564          xerror("glp_delete_prob: operation not allowed\n");
       
  1565       delete_prob(lp);
       
  1566       xfree(lp);
       
  1567       return;
       
  1568 }
       
  1569 
       
  1570 /* eof */