diff options
Diffstat (limited to 'glpk-5.0/src/api/wrmcf.c')
| -rw-r--r-- | glpk-5.0/src/api/wrmcf.c | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/glpk-5.0/src/api/wrmcf.c b/glpk-5.0/src/api/wrmcf.c new file mode 100644 index 0000000..234bc05 --- /dev/null +++ b/glpk-5.0/src/api/wrmcf.c @@ -0,0 +1,120 @@ +/* wrmcf.c (write min-cost flow problem data in DIMACS format) */ + +/*********************************************************************** +* This code is part of GLPK (GNU Linear Programming Kit). +* Copyright (C) 2009-2016 Free Software Foundation, Inc. +* Written by Andrew Makhorin <mao@gnu.org>. +* +* GLPK is free software: you can redistribute it and/or modify it +* under the terms of the GNU General Public License as published by +* the Free Software Foundation, either version 3 of the License, or +* (at your option) any later version. +* +* GLPK is distributed in the hope that it will be useful, but WITHOUT +* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY +* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public +* License for more details. +* +* You should have received a copy of the GNU General Public License +* along with GLPK. If not, see <http://www.gnu.org/licenses/>. +***********************************************************************/ + +#include "env.h" +#include "glpk.h" + +#define xfprintf glp_format + +/*********************************************************************** +* NAME +* +* glp_write_mincost - write min-cost flow probl. data in DIMACS format +* +* SYNOPSIS +* +* int glp_write_mincost(glp_graph *G, int v_rhs, int a_low, int a_cap, +* int a_cost, const char *fname); +* +* DESCRIPTION +* +* The routine glp_write_mincost writes minimum cost flow problem data +* in DIMACS format to a text file. +* +* RETURNS +* +* If the operation was successful, the routine returns zero. Otherwise +* it prints an error message and returns non-zero. */ + +int glp_write_mincost(glp_graph *G, int v_rhs, int a_low, int a_cap, + int a_cost, const char *fname) +{ glp_file *fp; + glp_vertex *v; + glp_arc *a; + int i, count = 0, ret; + double rhs, low, cap, cost; + if (v_rhs >= 0 && v_rhs > G->v_size - (int)sizeof(double)) + xerror("glp_write_mincost: v_rhs = %d; invalid offset\n", + v_rhs); + if (a_low >= 0 && a_low > G->a_size - (int)sizeof(double)) + xerror("glp_write_mincost: a_low = %d; invalid offset\n", + a_low); + if (a_cap >= 0 && a_cap > G->a_size - (int)sizeof(double)) + xerror("glp_write_mincost: a_cap = %d; invalid offset\n", + a_cap); + if (a_cost >= 0 && a_cost > G->a_size - (int)sizeof(double)) + xerror("glp_write_mincost: a_cost = %d; invalid offset\n", + a_cost); + xprintf("Writing min-cost flow problem data to '%s'...\n", + fname); + fp = glp_open(fname, "w"); + if (fp == NULL) + { xprintf("Unable to create '%s' - %s\n", fname, get_err_msg()); + ret = 1; + goto done; + } + xfprintf(fp, "c %s\n", + G->name == NULL ? "unknown" : G->name), count++; + xfprintf(fp, "p min %d %d\n", G->nv, G->na), count++; + if (v_rhs >= 0) + { for (i = 1; i <= G->nv; i++) + { v = G->v[i]; + memcpy(&rhs, (char *)v->data + v_rhs, sizeof(double)); + if (rhs != 0.0) + xfprintf(fp, "n %d %.*g\n", i, DBL_DIG, rhs), count++; + } + } + for (i = 1; i <= G->nv; i++) + { v = G->v[i]; + for (a = v->out; a != NULL; a = a->t_next) + { if (a_low >= 0) + memcpy(&low, (char *)a->data + a_low, sizeof(double)); + else + low = 0.0; + if (a_cap >= 0) + memcpy(&cap, (char *)a->data + a_cap, sizeof(double)); + else + cap = 1.0; + if (a_cost >= 0) + memcpy(&cost, (char *)a->data + a_cost, sizeof(double)); + else + cost = 0.0; + xfprintf(fp, "a %d %d %.*g %.*g %.*g\n", + a->tail->i, a->head->i, DBL_DIG, low, DBL_DIG, cap, + DBL_DIG, cost), count++; + } + } + xfprintf(fp, "c eof\n"), count++; +#if 0 /* FIXME */ + xfflush(fp); +#endif + if (glp_ioerr(fp)) + { xprintf("Write error on '%s' - %s\n", fname, get_err_msg()); + ret = 1; + goto done; + } + xprintf("%d lines were written\n", count); + ret = 0; +done: if (fp != NULL) glp_close(fp); + return ret; +} + +/* eof */ |