glpapi01.c

著名的大规模线性规划求解器源码GLPK.C语言版本,可以修剪.内有详细帮助文档.

      if (ncs > N_MAX - lp->n)
         xerror("glp_add_cols: ncs = %d; too many columns\n", ncs);
      n_new = lp->n + ncs;
      /* increase the room, if necessary */
      if (lp->n_max < n_new)
      {  GLPCOL **save = lp->col;
         while (lp->n_max < n_new)
         {  lp->n_max += lp->n_max;
            xassert(lp->n_max > 0);
         }
         lp->col = xcalloc(1+lp->n_max, sizeof(GLPCOL *));
         memcpy(&lp->col[1], &save[1], lp->n * sizeof(GLPCOL *));
         xfree(save);
      }
      /* add new columns to the end of the column list */
      for (j = lp->n+1; j <= n_new; j++)
      {  /* create column descriptor */
         lp->col[j] = col = dmp_get_atom(lp->pool, sizeof(GLPCOL));
         col->j = j;
         col->name = NULL;
         col->node = NULL;
         col->kind = GLP_CV;
         col->type = GLP_FX;
         col->lb = col->ub = 0.0;
         col->coef = 0.0;
         col->ptr = NULL;
         col->sjj = 1.0;
         col->stat = GLP_NS;
#if 0
         col->bind = -1;
#else
         col->bind = 0; /* the basis may remain valid */
#endif
         col->prim = col->dual = 0.0;
         col->pval = col->dval = 0.0;
         col->mipx = 0.0;
      }
      /* set new number of columns */
      lp->n = n_new;
      /* return the ordinal number of the first column added */
      return n_new - ncs + 1;
}

/***********************************************************************
*  NAME
*
*  glp_set_row_name - assign (change) row name
*
*  SYNOPSIS
*
*  void glp_set_row_name(glp_prob *lp, int i, const char *name);
*
*  DESCRIPTION
*
*  The routine glp_set_row_name assigns a given symbolic name (1 up to
*  255 characters) to i-th row (auxiliary variable) of the specified
*  problem object.
*
*  If the parameter name is NULL or empty string, the routine erases an
*  existing name of i-th row. */

void glp_set_row_name(glp_prob *lp, int i, const char *name)
{     glp_tree *tree = lp->tree;
      GLPROW *row;
      if (!(1 <= i && i <= lp->m))
         xerror("glp_set_row_name: i = %d; row number out of range\n",
            i);
      row = lp->row[i];
      if (tree != NULL && tree->reason != 0)
      {  xassert(tree->curr != NULL);
         xassert(row->level == tree->curr->level);
      }
      if (row->name != NULL)
      {  if (row->node != NULL)
         {  xassert(lp->r_tree != NULL);
            avl_delete_node(lp->r_tree, row->node);
            row->node = NULL;
         }
         dmp_free_atom(lp->pool, row->name, strlen(row->name)+1);
         row->name = NULL;
      }
      if (!(name == NULL || name[0] == '\0'))
      {  int k;
         for (k = 0; name[k] != '\0'; k++)
         {  if (k == 256)
               xerror("glp_set_row_name: i = %d; row name too long\n",
                  i);
            if (iscntrl((unsigned char)name[k]))
               xerror("glp_set_row_name: i = %d: row name contains inva"
                  "lid character(s)\n", i);
         }
         row->name = dmp_get_atom(lp->pool, strlen(name)+1);
         strcpy(row->name, name);
         if (lp->r_tree != NULL)
         {  xassert(row->node == NULL);
            row->node = avl_insert_node(lp->r_tree, row->name);
            avl_set_node_link(row->node, row);
         }
      }
      return;
}

/***********************************************************************
*  NAME
*
*  glp_set_col_name - assign (change) column name
*
*  SYNOPSIS
*
*  void glp_set_col_name(glp_prob *lp, int j, const char *name);
*
*  DESCRIPTION
*
*  The routine glp_set_col_name assigns a given symbolic name (1 up to
*  255 characters) to j-th column (structural variable) of the specified
*  problem object.
*
*  If the parameter name is NULL or empty string, the routine erases an
*  existing name of j-th column. */

void glp_set_col_name(glp_prob *lp, int j, const char *name)
{     glp_tree *tree = lp->tree;
      GLPCOL *col;
      if (tree != NULL && tree->reason != 0)
         xerror("glp_set_col_name: operation not allowed\n");
      if (!(1 <= j && j <= lp->n))
         xerror("glp_set_col_name: j = %d; column number out of range\n"
            , j);
      col = lp->col[j];
      if (col->name != NULL)
      {  if (col->node != NULL)
         {  xassert(lp->c_tree != NULL);
            avl_delete_node(lp->c_tree, col->node);
            col->node = NULL;
         }
         dmp_free_atom(lp->pool, col->name, strlen(col->name)+1);
         col->name = NULL;
      }
      if (!(name == NULL || name[0] == '\0'))
      {  int k;
         for (k = 0; name[k] != '\0'; k++)
         {  if (k == 256)
               xerror("glp_set_col_name: j = %d; column name too long\n"
                  , j);
            if (iscntrl((unsigned char)name[k]))
               xerror("glp_set_col_name: j = %d: column name contains i"
                  "nvalid character(s)\n", j);
         }
         col->name = dmp_get_atom(lp->pool, strlen(name)+1);
         strcpy(col->name, name);
         if (lp->c_tree != NULL && col->name != NULL)
         {  xassert(col->node == NULL);
            col->node = avl_insert_node(lp->c_tree, col->name);
            avl_set_node_link(col->node, col);
         }
      }
      return;
}

/***********************************************************************
*  NAME
*
*  glp_set_row_bnds - set (change) row bounds
*
*  SYNOPSIS
*
*  void glp_set_row_bnds(glp_prob *lp, int i, int type, double lb,
*     double ub);
*
*  DESCRIPTION
*
*  The routine glp_set_row_bnds sets (changes) the type and bounds of
*  i-th row (auxiliary variable) of the specified problem object.
*
*  Parameters type, lb, and ub specify the type, lower bound, and upper
*  bound, respectively, as follows:
*
*     Type           Bounds        Comments
*     ------------------------------------------------------
*     GLP_FR   -inf <  x <  +inf   Free variable
*     GLP_LO     lb <= x <  +inf   Variable with lower bound
*     GLP_UP   -inf <  x <=  ub    Variable with upper bound
*     GLP_DB     lb <= x <=  ub    Double-bounded variable
*     GLP_FX           x  =  lb    Fixed variable
*
*  where x is the auxiliary variable associated with i-th row.
*
*  If the row has no lower bound, the parameter lb is ignored. If the
*  row has no upper bound, the parameter ub is ignored. If the row is
*  an equality constraint (i.e. the corresponding auxiliary variable is
*  of fixed type), only the parameter lb is used while the parameter ub
*  is ignored. */

void glp_set_row_bnds(glp_prob *lp, int i, int type, double lb,
      double ub)
{     GLPROW *row;
      if (!(1 <= i && i <= lp->m))
         xerror("glp_set_row_bnds: i = %d; row number out of range\n",
            i);
      row = lp->row[i];
      row->type = type;
      switch (type)
      {  case GLP_FR:
            row->lb = row->ub = 0.0;
            if (row->stat != GLP_BS) row->stat = GLP_NF;
            break;
         case GLP_LO:
            row->lb = lb, row->ub = 0.0;
            if (row->stat != GLP_BS) row->stat = GLP_NL;
            break;
         case GLP_UP:
            row->lb = 0.0, row->ub = ub;
            if (row->stat != GLP_BS) row->stat = GLP_NU;
            break;
         case GLP_DB:
            row->lb = lb, row->ub = ub;
            if (!(row->stat == GLP_BS ||
                  row->stat == GLP_NL || row->stat == GLP_NU))
               row->stat = (fabs(lb) <= fabs(ub) ? GLP_NL : GLP_NU);
            break;
         case GLP_FX:
            row->lb = row->ub = lb;
            if (row->stat != GLP_BS) row->stat = GLP_NS;
            break;
         default:
            xerror("glp_set_row_bnds: i = %d; type = %d; invalid row ty"
               "pe\n", i, type);
      }
      return;
}

/***********************************************************************
*  NAME
*
*  glp_set_col_bnds - set (change) column bounds
*
*  SYNOPSIS
*
*  void glp_set_col_bnds(glp_prob *lp, int j, int type, double lb,
*     double ub);
*
*  DESCRIPTION
*
*  The routine glp_set_col_bnds sets (changes) the type and bounds of
*  j-th column (structural variable) of the specified problem object.
*
*  Parameters type, lb, and ub specify the type, lower bound, and upper
*  bound, respectively, as follows:
*
*     Type           Bounds        Comments
*     ------------------------------------------------------
*     GLP_FR   -inf <  x <  +inf   Free variable
*     GLP_LO     lb <= x <  +inf   Variable with lower bound
*     GLP_UP   -inf <  x <=  ub    Variable with upper bound
*     GLP_DB     lb <= x <=  ub    Double-bounded variable
*     GLP_FX           x  =  lb    Fixed variable
*
*  where x is the structural variable associated with j-th column.
*
*  If the column has no lower bound, the parameter lb is ignored. If the
*  column has no upper bound, the parameter ub is ignored. If the column
*  is of fixed type, only the parameter lb is used while the parameter
*  ub is ignored. */

void glp_set_col_bnds(glp_prob *lp, int j, int type, double lb,
      double ub)
{     GLPCOL *col;
      if (!(1 <= j && j <= lp->n))
         xerror("glp_set_col_bnds: j = %d; column number out of range\n"
            , j);
      col = lp->col[j];
      col->type = type;
      switch (type)
      {  case GLP_FR:
            col->lb = col->ub = 0.0;
            if (col->stat != GLP_BS) col->stat = GLP_NF;
            break;
         case GLP_LO:
            col->lb = lb, col->ub = 0.0;
            if (col->stat != GLP_BS) col->stat = GLP_NL;
            break;
         case GLP_UP:
            col->lb = 0.0, col->ub = ub;
            if (col->stat != GLP_BS) col->stat = GLP_NU;
            break;
         case GLP_DB:
            col->lb = lb, col->ub = ub;
            if (!(col->stat == GLP_BS ||
                  col->stat == GLP_NL || col->stat == GLP_NU))
               col->stat = (fabs(lb) <= fabs(ub) ? GLP_NL : GLP_NU);
            break;
         case GLP_FX:
            col->lb = col->ub = lb;
            if (col->stat != GLP_BS) col->stat = GLP_NS;
            break;
         default:
            xerror("glp_set_col_bnds: j = %d; type = %d; invalid column"
               " type\n", j, type);
      }
      return;
}

/***********************************************************************
*  NAME
*
*  glp_set_obj_coef - set (change) obj. coefficient or constant term
*
*  SYNOPSIS
*
*  void glp_set_obj_coef(glp_prob *lp, int j, double coef);
*
*  DESCRIPTION
*
*  The routine glp_set_obj_coef sets (changes) objective coefficient at
*  j-th column (structural variable) of the specified problem object.
*
*  If the parameter j is 0, the routine sets (changes) the constant term
*  ("shift") of the objective function. */

void glp_set_obj_coef(glp_prob *lp, int j, double coef)
{     glp_tree *tree = lp->tree;
      if (tree != NULL && tree->reason != 0)
         xerror("glp_set_obj_coef: operation not allowed\n");
      if (!(0 <= j && j <= lp->n))
         xerror("glp_set_obj_coef: j = %d; column number out of range\n"
            , j);
      if (j == 0)
         lp->c0 = coef;
      else
         lp->col[j]->coef = coef;
      return;
}

/***********************************************************************
*  NAME
*
*  glp_set_mat_row - set (replace) row of the constraint matrix
*
*  SYNOPSIS
*
*  void glp_set_mat_row(glp_prob *lp, int i, int len, const int ind[],
*     const double val[]);
*
*  DESCRIPTION
*
*  The routine glp_set_mat_row stores (replaces) the contents of i-th
*  row of the constraint matrix of the specified problem object.