COIN-OR::LEMON - Graph Library

source: glpk-cmake/src/glpapi03.c @ 1:c445c931472f

Last change on this file since 1:c445c931472f was 1:c445c931472f, checked in by Alpar Juttner <alpar@…>, 10 years ago

Import glpk-4.45

  • Generated files and doc/notes are removed
File size: 5.1 KB
Line 
1/* glpapi03.c (row and column searching 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 "glpapi.h"
26
27/***********************************************************************
28*  NAME
29*
30*  glp_create_index - create the name index
31*
32*  SYNOPSIS
33*
34*  void glp_create_index(glp_prob *lp);
35*
36*  DESCRIPTION
37*
38*  The routine glp_create_index creates the name index for the
39*  specified problem object. The name index is an auxiliary data
40*  structure, which is intended to quickly (i.e. for logarithmic time)
41*  find rows and columns by their names.
42*
43*  This routine can be called at any time. If the name index already
44*  exists, the routine does nothing. */
45
46void glp_create_index(glp_prob *lp)
47{     GLPROW *row;
48      GLPCOL *col;
49      int i, j;
50      /* create row name index */
51      if (lp->r_tree == NULL)
52      {  lp->r_tree = avl_create_tree(avl_strcmp, NULL);
53         for (i = 1; i <= lp->m; i++)
54         {  row = lp->row[i];
55            xassert(row->node == NULL);
56            if (row->name != NULL)
57            {  row->node = avl_insert_node(lp->r_tree, row->name);
58               avl_set_node_link(row->node, row);
59            }
60         }
61      }
62      /* create column name index */
63      if (lp->c_tree == NULL)
64      {  lp->c_tree = avl_create_tree(avl_strcmp, NULL);
65         for (j = 1; j <= lp->n; j++)
66         {  col = lp->col[j];
67            xassert(col->node == NULL);
68            if (col->name != NULL)
69            {  col->node = avl_insert_node(lp->c_tree, col->name);
70               avl_set_node_link(col->node, col);
71            }
72         }
73      }
74      return;
75}
76
77/***********************************************************************
78*  NAME
79*
80*  glp_find_row - find row by its name
81*
82*  SYNOPSIS
83*
84*  int glp_find_row(glp_prob *lp, const char *name);
85*
86*  RETURNS
87*
88*  The routine glp_find_row returns the ordinal number of a row,
89*  which is assigned (by the routine glp_set_row_name) the specified
90*  symbolic name. If no such row exists, the routine returns 0. */
91
92int glp_find_row(glp_prob *lp, const char *name)
93{     AVLNODE *node;
94      int i = 0;
95      if (lp->r_tree == NULL)
96         xerror("glp_find_row: row name index does not exist\n");
97      if (!(name == NULL || name[0] == '\0' || strlen(name) > 255))
98      {  node = avl_find_node(lp->r_tree, name);
99         if (node != NULL)
100            i = ((GLPROW *)avl_get_node_link(node))->i;
101      }
102      return i;
103}
104
105/***********************************************************************
106*  NAME
107*
108*  glp_find_col - find column by its name
109*
110*  SYNOPSIS
111*
112*  int glp_find_col(glp_prob *lp, const char *name);
113*
114*  RETURNS
115*
116*  The routine glp_find_col returns the ordinal number of a column,
117*  which is assigned (by the routine glp_set_col_name) the specified
118*  symbolic name. If no such column exists, the routine returns 0. */
119
120int glp_find_col(glp_prob *lp, const char *name)
121{     AVLNODE *node;
122      int j = 0;
123      if (lp->c_tree == NULL)
124         xerror("glp_find_col: column name index does not exist\n");
125      if (!(name == NULL || name[0] == '\0' || strlen(name) > 255))
126      {  node = avl_find_node(lp->c_tree, name);
127         if (node != NULL)
128            j = ((GLPCOL *)avl_get_node_link(node))->j;
129      }
130      return j;
131}
132
133/***********************************************************************
134*  NAME
135*
136*  glp_delete_index - delete the name index
137*
138*  SYNOPSIS
139*
140*  void glp_delete_index(glp_prob *lp);
141*
142*  DESCRIPTION
143*
144*  The routine glp_delete_index deletes the name index previously
145*  created by the routine glp_create_index and frees the memory
146*  allocated to this auxiliary data structure.
147*
148*  This routine can be called at any time. If the name index does not
149*  exist, the routine does nothing. */
150
151void glp_delete_index(glp_prob *lp)
152{     int i, j;
153      /* delete row name index */
154      if (lp->r_tree != NULL)
155      {  for (i = 1; i <= lp->m; i++) lp->row[i]->node = NULL;
156         avl_delete_tree(lp->r_tree), lp->r_tree = NULL;
157      }
158      /* delete column name index */
159      if (lp->c_tree != NULL)
160      {  for (j = 1; j <= lp->n; j++) lp->col[j]->node = NULL;
161         avl_delete_tree(lp->c_tree), lp->c_tree = NULL;
162      }
163      return;
164}
165
166/* eof */
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