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/* glpdmx.c (reading/writing data in DIMACS format) */
/***********************************************************************
* This code is part of GLPK (GNU Linear Programming Kit).
*
* Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,
* 2009, 2010, 2011, 2013 Andrew Makhorin, Department for Applied
* Informatics, Moscow Aviation Institute, Moscow, Russia. All rights
* reserved. E-mail: <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 "misc.h"
#include "prob.h"
#define xfprintf glp_format
struct csa
{ /* common storage area */
jmp_buf jump;
/* label for go to in case of error */
const char *fname;
/* name of input text file */
glp_file *fp;
/* stream assigned to input text file */
int count;
/* line count */
int c;
/* current character */
char field[255+1];
/* data field */
int empty;
/* warning 'empty line ignored' was printed */
int nonint;
/* warning 'non-integer data detected' was printed */
};
static void error(struct csa *csa, const char *fmt, ...)
{ /* print error message and terminate processing */
va_list arg;
xprintf("%s:%d: error: ", csa->fname, csa->count);
va_start(arg, fmt);
xvprintf(fmt, arg);
va_end(arg);
xprintf("\n");
longjmp(csa->jump, 1);
/* no return */
}
static void warning(struct csa *csa, const char *fmt, ...)
{ /* print warning message and continue processing */
va_list arg;
xprintf("%s:%d: warning: ", csa->fname, csa->count);
va_start(arg, fmt);
xvprintf(fmt, arg);
va_end(arg);
xprintf("\n");
return;
}
static void read_char(struct csa *csa)
{ /* read character from input text file */
int c;
if (csa->c == '\n') csa->count++;
c = glp_getc(csa->fp);
if (c < 0)
{ if (glp_ioerr(csa->fp))
error(csa, "read error - %s", get_err_msg());
else if (csa->c == '\n')
error(csa, "unexpected end of file");
else
{ warning(csa, "missing final end of line");
c = '\n';
}
}
else if (c == '\n')
;
else if (isspace(c))
c = ' ';
else if (iscntrl(c))
error(csa, "invalid control character 0x%02X", c);
csa->c = c;
return;
}
static void read_designator(struct csa *csa)
{ /* read one-character line designator */
xassert(csa->c == '\n');
read_char(csa);
for (;;)
{ /* skip preceding white-space characters */
while (csa->c == ' ')
read_char(csa);
if (csa->c == '\n')
{ /* ignore empty line */
if (!csa->empty)
{ warning(csa, "empty line ignored");
csa->empty = 1;
}
read_char(csa);
}
else if (csa->c == 'c')
{ /* skip comment line */
while (csa->c != '\n')
read_char(csa);
read_char(csa);
}
else
{ /* hmm... looks like a line designator */
csa->field[0] = (char)csa->c, csa->field[1] = '\0';
/* check that it is followed by a white-space character */
read_char(csa);
if (!(csa->c == ' ' || csa->c == '\n'))
error(csa, "line designator missing or invalid");
break;
}
}
return;
}
static void read_field(struct csa *csa)
{ /* read data field */
int len = 0;
/* skip preceding white-space characters */
while (csa->c == ' ')
read_char(csa);
/* scan data field */
if (csa->c == '\n')
error(csa, "unexpected end of line");
while (!(csa->c == ' ' || csa->c == '\n'))
{ if (len == sizeof(csa->field)-1)
error(csa, "data field `%.15s...' too long", csa->field);
csa->field[len++] = (char)csa->c;
read_char(csa);
}
csa->field[len] = '\0';
return;
}
static void end_of_line(struct csa *csa)
{ /* skip white-space characters until end of line */
while (csa->c == ' ')
read_char(csa);
if (csa->c != '\n')
error(csa, "too many data fields specified");
return;
}
static void check_int(struct csa *csa, double num)
{ /* print a warning if non-integer data are detected */
if (!csa->nonint && num != floor(num))
{ warning(csa, "non-integer data detected");
csa->nonint = 1;
}
return;
}
/***********************************************************************
* NAME
*
* glp_read_mincost - read min-cost flow problem data in DIMACS format
*
* SYNOPSIS
*
* int glp_read_mincost(glp_graph *G, int v_rhs, int a_low, int a_cap,
* int a_cost, const char *fname);
*
* DESCRIPTION
*
* The routine glp_read_mincost reads minimum cost flow problem data in
* DIMACS format from 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_read_mincost(glp_graph *G, int v_rhs, int a_low, int a_cap,
int a_cost, const char *fname)
{ struct csa _csa, *csa = &_csa;
glp_vertex *v;
glp_arc *a;
int i, j, k, nv, na, ret = 0;
double rhs, low, cap, cost;
char *flag = NULL;
if (v_rhs >= 0 && v_rhs > G->v_size - (int)sizeof(double))
xerror("glp_read_mincost: v_rhs = %d; invalid offset\n",
v_rhs);
if (a_low >= 0 && a_low > G->a_size - (int)sizeof(double))
xerror("glp_read_mincost: a_low = %d; invalid offset\n",
a_low);
if (a_cap >= 0 && a_cap > G->a_size - (int)sizeof(double))
xerror("glp_read_mincost: a_cap = %d; invalid offset\n",
a_cap);
if (a_cost >= 0 && a_cost > G->a_size - (int)sizeof(double))
xerror("glp_read_mincost: a_cost = %d; invalid offset\n",
a_cost);
glp_erase_graph(G, G->v_size, G->a_size);
if (setjmp(csa->jump))
{ ret = 1;
goto done;
}
csa->fname = fname;
csa->fp = NULL;
csa->count = 0;
csa->c = '\n';
csa->field[0] = '\0';
csa->empty = csa->nonint = 0;
xprintf("Reading min-cost flow problem data from `%s'...\n",
fname);
csa->fp = glp_open(fname, "r");
if (csa->fp == NULL)
{ xprintf("Unable to open `%s' - %s\n", fname, get_err_msg());
longjmp(csa->jump, 1);
}
/* read problem line */
read_designator(csa);
if (strcmp(csa->field, "p") != 0)
error(csa, "problem line missing or invalid");
read_field(csa);
if (strcmp(csa->field, "min") != 0)
error(csa, "wrong problem designator; `min' expected");
read_field(csa);
if (!(str2int(csa->field, &nv) == 0 && nv >= 0))
error(csa, "number of nodes missing or invalid");
read_field(csa);
if (!(str2int(csa->field, &na) == 0 && na >= 0))
error(csa, "number of arcs missing or invalid");
xprintf("Flow network has %d node%s and %d arc%s\n",
nv, nv == 1 ? "" : "s", na, na == 1 ? "" : "s");
if (nv > 0) glp_add_vertices(G, nv);
end_of_line(csa);
/* read node descriptor lines */
flag = xcalloc(1+nv, sizeof(char));
memset(&flag[1], 0, nv * sizeof(char));
if (v_rhs >= 0)
{ rhs = 0.0;
for (i = 1; i <= nv; i++)
{ v = G->v[i];
memcpy((char *)v->data + v_rhs, &rhs, sizeof(double));
}
}
for (;;)
{ read_designator(csa);
if (strcmp(csa->field, "n") != 0) break;
read_field(csa);
if (str2int(csa->field, &i) != 0)
error(csa, "node number missing or invalid");
if (!(1 <= i && i <= nv))
error(csa, "node number %d out of range", i);
if (flag[i])
error(csa, "duplicate descriptor of node %d", i);
read_field(csa);
if (str2num(csa->field, &rhs) != 0)
error(csa, "node supply/demand missing or invalid");
check_int(csa, rhs);
if (v_rhs >= 0)
{ v = G->v[i];
memcpy((char *)v->data + v_rhs, &rhs, sizeof(double));
}
flag[i] = 1;
end_of_line(csa);
}
xfree(flag), flag = NULL;
/* read arc descriptor lines */
for (k = 1; k <= na; k++)
{ if (k > 1) read_designator(csa);
if (strcmp(csa->field, "a") != 0)
error(csa, "wrong line designator; `a' expected");
read_field(csa);
if (str2int(csa->field, &i) != 0)
error(csa, "starting node number missing or invalid");
if (!(1 <= i && i <= nv))
error(csa, "starting node number %d out of range", i);
read_field(csa);
if (str2int(csa->field, &j) != 0)
error(csa, "ending node number missing or invalid");
if (!(1 <= j && j <= nv))
error(csa, "ending node number %d out of range", j);
read_field(csa);
if (!(str2num(csa->field, &low) == 0 && low >= 0.0))
error(csa, "lower bound of arc flow missing or invalid");
check_int(csa, low);
read_field(csa);
if (!(str2num(csa->field, &cap) == 0 && cap >= low))
error(csa, "upper bound of arc flow missing or invalid");
check_int(csa, cap);
read_field(csa);
if (str2num(csa->field, &cost) != 0)
error(csa, "per-unit cost of arc flow missing or invalid");
check_int(csa, cost);
a = glp_add_arc(G, i, j);
if (a_low >= 0)
memcpy((char *)a->data + a_low, &low, sizeof(double));
if (a_cap >= 0)
memcpy((char *)a->data + a_cap, &cap, sizeof(double));
if (a_cost >= 0)
memcpy((char *)a->data + a_cost, &cost, sizeof(double));
end_of_line(csa);
}
xprintf("%d lines were read\n", csa->count);
done: if (ret) glp_erase_graph(G, G->v_size, G->a_size);
if (csa->fp != NULL) glp_close(csa->fp);
if (flag != NULL) xfree(flag);
return ret;
}
/***********************************************************************
* NAME
*
* glp_write_mincost - write min-cost flow problem 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;
}
/***********************************************************************
* NAME
*
* glp_read_maxflow - read maximum flow problem data in DIMACS format
*
* SYNOPSIS
*
* int glp_read_maxflow(glp_graph *G, int *s, int *t, int a_cap,
* const char *fname);
*
* DESCRIPTION
*
* The routine glp_read_maxflow reads maximum flow problem data in
* DIMACS format from 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_read_maxflow(glp_graph *G, int *_s, int *_t, int a_cap,
const char *fname)
{ struct csa _csa, *csa = &_csa;
glp_arc *a;
int i, j, k, s, t, nv, na, ret = 0;
double cap;
if (a_cap >= 0 && a_cap > G->a_size - (int)sizeof(double))
xerror("glp_read_maxflow: a_cap = %d; invalid offset\n",
a_cap);
glp_erase_graph(G, G->v_size, G->a_size);
if (setjmp(csa->jump))
{ ret = 1;
goto done;
}
csa->fname = fname;
csa->fp = NULL;
csa->count = 0;
csa->c = '\n';
csa->field[0] = '\0';
csa->empty = csa->nonint = 0;
xprintf("Reading maximum flow problem data from `%s'...\n",
fname);
csa->fp = glp_open(fname, "r");
if (csa->fp == NULL)
{ xprintf("Unable to open `%s' - %s\n", fname, get_err_msg());
longjmp(csa->jump, 1);
}
/* read problem line */
read_designator(csa);
if (strcmp(csa->field, "p") != 0)
error(csa, "problem line missing or invalid");
read_field(csa);
if (strcmp(csa->field, "max") != 0)
error(csa, "wrong problem designator; `max' expected");
read_field(csa);
if (!(str2int(csa->field, &nv) == 0 && nv >= 2))
error(csa, "number of nodes missing or invalid");
read_field(csa);
if (!(str2int(csa->field, &na) == 0 && na >= 0))
error(csa, "number of arcs missing or invalid");
xprintf("Flow network has %d node%s and %d arc%s\n",
nv, nv == 1 ? "" : "s", na, na == 1 ? "" : "s");
if (nv > 0) glp_add_vertices(G, nv);
end_of_line(csa);
/* read node descriptor lines */
s = t = 0;
for (;;)
{ read_designator(csa);
if (strcmp(csa->field, "n") != 0) break;
read_field(csa);
if (str2int(csa->field, &i) != 0)
error(csa, "node number missing or invalid");
if (!(1 <= i && i <= nv))
error(csa, "node number %d out of range", i);
read_field(csa);
if (strcmp(csa->field, "s") == 0)
{ if (s > 0)
error(csa, "only one source node allowed");
s = i;
}
else if (strcmp(csa->field, "t") == 0)
{ if (t > 0)
error(csa, "only one sink node allowed");
t = i;
}
else
error(csa, "wrong node designator; `s' or `t' expected");
if (s > 0 && s == t)
error(csa, "source and sink nodes must be distinct");
end_of_line(csa);
}
if (s == 0)
error(csa, "source node descriptor missing\n");
if (t == 0)
error(csa, "sink node descriptor missing\n");
if (_s != NULL) *_s = s;
if (_t != NULL) *_t = t;
/* read arc descriptor lines */
for (k = 1; k <= na; k++)
{ if (k > 1) read_designator(csa);
if (strcmp(csa->field, "a") != 0)
error(csa, "wrong line designator; `a' expected");
read_field(csa);
if (str2int(csa->field, &i) != 0)
error(csa, "starting node number missing or invalid");
if (!(1 <= i && i <= nv))
error(csa, "starting node number %d out of range", i);
read_field(csa);
if (str2int(csa->field, &j) != 0)
error(csa, "ending node number missing or invalid");
if (!(1 <= j && j <= nv))
error(csa, "ending node number %d out of range", j);
read_field(csa);
if (!(str2num(csa->field, &cap) == 0 && cap >= 0.0))
error(csa, "arc capacity missing or invalid");
check_int(csa, cap);
a = glp_add_arc(G, i, j);
if (a_cap >= 0)
memcpy((char *)a->data + a_cap, &cap, sizeof(double));
end_of_line(csa);
}
xprintf("%d lines were read\n", csa->count);
done: if (ret) glp_erase_graph(G, G->v_size, G->a_size);
if (csa->fp != NULL) glp_close(csa->fp);
return ret;
}
/***********************************************************************
* NAME
*
* glp_write_maxflow - write maximum flow problem data in DIMACS format
*
* SYNOPSIS
*
* int glp_write_maxflow(glp_graph *G, int s, int t, int a_cap,
* const char *fname);
*
* DESCRIPTION
*
* The routine glp_write_maxflow writes maximum 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_maxflow(glp_graph *G, int s, int t, int a_cap,
const char *fname)
{ glp_file *fp;
glp_vertex *v;
glp_arc *a;
int i, count = 0, ret;
double cap;
if (!(1 <= s && s <= G->nv))
xerror("glp_write_maxflow: s = %d; source node number out of r"
"ange\n", s);
if (!(1 <= t && t <= G->nv))
xerror("glp_write_maxflow: t = %d: sink node number out of ran"
"ge\n", t);
if (a_cap >= 0 && a_cap > G->a_size - (int)sizeof(double))
xerror("glp_write_mincost: a_cap = %d; invalid offset\n",
a_cap);
xprintf("Writing maximum 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 max %d %d\n", G->nv, G->na), count++;
xfprintf(fp, "n %d s\n", s), count++;
xfprintf(fp, "n %d t\n", t), count++;
for (i = 1; i <= G->nv; i++)
{ v = G->v[i];
for (a = v->out; a != NULL; a = a->t_next)
{ if (a_cap >= 0)
memcpy(&cap, (char *)a->data + a_cap, sizeof(double));
else
cap = 1.0;
xfprintf(fp, "a %d %d %.*g\n",
a->tail->i, a->head->i, DBL_DIG, cap), 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;
}
/***********************************************************************
* NAME
*
* glp_read_asnprob - read assignment problem data in DIMACS format
*
* SYNOPSIS
*
* int glp_read_asnprob(glp_graph *G, int v_set, int a_cost,
* const char *fname);
*
* DESCRIPTION
*
* The routine glp_read_asnprob reads assignment problem data in DIMACS
* format from 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_read_asnprob(glp_graph *G, int v_set, int a_cost, const char
*fname)
{ struct csa _csa, *csa = &_csa;
glp_vertex *v;
glp_arc *a;
int nv, na, n1, i, j, k, ret = 0;
double cost;
char *flag = NULL;
if (v_set >= 0 && v_set > G->v_size - (int)sizeof(int))
xerror("glp_read_asnprob: v_set = %d; invalid offset\n",
v_set);
if (a_cost >= 0 && a_cost > G->a_size - (int)sizeof(double))
xerror("glp_read_asnprob: a_cost = %d; invalid offset\n",
a_cost);
glp_erase_graph(G, G->v_size, G->a_size);
if (setjmp(csa->jump))
{ ret = 1;
goto done;
}
csa->fname = fname;
csa->fp = NULL;
csa->count = 0;
csa->c = '\n';
csa->field[0] = '\0';
csa->empty = csa->nonint = 0;
xprintf("Reading assignment problem data from `%s'...\n", fname);
csa->fp = glp_open(fname, "r");
if (csa->fp == NULL)
{ xprintf("Unable to open `%s' - %s\n", fname, get_err_msg());
longjmp(csa->jump, 1);
}
/* read problem line */
read_designator(csa);
if (strcmp(csa->field, "p") != 0)
error(csa, "problem line missing or invalid");
read_field(csa);
if (strcmp(csa->field, "asn") != 0)
error(csa, "wrong problem designator; `asn' expected");
read_field(csa);
if (!(str2int(csa->field, &nv) == 0 && nv >= 0))
error(csa, "number of nodes missing or invalid");
read_field(csa);
if (!(str2int(csa->field, &na) == 0 && na >= 0))
error(csa, "number of arcs missing or invalid");
if (nv > 0) glp_add_vertices(G, nv);
end_of_line(csa);
/* read node descriptor lines */
flag = xcalloc(1+nv, sizeof(char));
memset(&flag[1], 0, nv * sizeof(char));
n1 = 0;
for (;;)
{ read_designator(csa);
if (strcmp(csa->field, "n") != 0) break;
read_field(csa);
if (str2int(csa->field, &i) != 0)
error(csa, "node number missing or invalid");
if (!(1 <= i && i <= nv))
error(csa, "node number %d out of range", i);
if (flag[i])
error(csa, "duplicate descriptor of node %d", i);
flag[i] = 1, n1++;
end_of_line(csa);
}
xprintf(
"Assignment problem has %d + %d = %d node%s and %d arc%s\n",
n1, nv - n1, nv, nv == 1 ? "" : "s", na, na == 1 ? "" : "s");
if (v_set >= 0)
{ for (i = 1; i <= nv; i++)
{ v = G->v[i];
k = (flag[i] ? 0 : 1);
memcpy((char *)v->data + v_set, &k, sizeof(int));
}
}
/* read arc descriptor lines */
for (k = 1; k <= na; k++)
{ if (k > 1) read_designator(csa);
if (strcmp(csa->field, "a") != 0)
error(csa, "wrong line designator; `a' expected");
read_field(csa);
if (str2int(csa->field, &i) != 0)
error(csa, "starting node number missing or invalid");
if (!(1 <= i && i <= nv))
error(csa, "starting node number %d out of range", i);
if (!flag[i])
error(csa, "node %d cannot be a starting node", i);
read_field(csa);
if (str2int(csa->field, &j) != 0)
error(csa, "ending node number missing or invalid");
if (!(1 <= j && j <= nv))
error(csa, "ending node number %d out of range", j);
if (flag[j])
error(csa, "node %d cannot be an ending node", j);
read_field(csa);
if (str2num(csa->field, &cost) != 0)
error(csa, "arc cost missing or invalid");
check_int(csa, cost);
a = glp_add_arc(G, i, j);
if (a_cost >= 0)
memcpy((char *)a->data + a_cost, &cost, sizeof(double));
end_of_line(csa);
}
xprintf("%d lines were read\n", csa->count);
done: if (ret) glp_erase_graph(G, G->v_size, G->a_size);
if (csa->fp != NULL) glp_close(csa->fp);
if (flag != NULL) xfree(flag);
return ret;
}
/***********************************************************************
* NAME
*
* glp_write_asnprob - write assignment problem data in DIMACS format
*
* SYNOPSIS
*
* int glp_write_asnprob(glp_graph *G, int v_set, int a_cost,
* const char *fname);
*
* DESCRIPTION
*
* The routine glp_write_asnprob writes assignment 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_asnprob(glp_graph *G, int v_set, int a_cost, const char
*fname)
{ glp_file *fp;
glp_vertex *v;
glp_arc *a;
int i, k, count = 0, ret;
double cost;
if (v_set >= 0 && v_set > G->v_size - (int)sizeof(int))
xerror("glp_write_asnprob: v_set = %d; invalid offset\n",
v_set);
if (a_cost >= 0 && a_cost > G->a_size - (int)sizeof(double))
xerror("glp_write_asnprob: a_cost = %d; invalid offset\n",
a_cost);
xprintf("Writing assignment 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 asn %d %d\n", G->nv, G->na), count++;
for (i = 1; i <= G->nv; i++)
{ v = G->v[i];
if (v_set >= 0)
memcpy(&k, (char *)v->data + v_set, sizeof(int));
else
k = (v->out != NULL ? 0 : 1);
if (k == 0)
xfprintf(fp, "n %d\n", i), count++;
}
for (i = 1; i <= G->nv; i++)
{ v = G->v[i];
for (a = v->out; a != NULL; a = a->t_next)
{ if (a_cost >= 0)
memcpy(&cost, (char *)a->data + a_cost, sizeof(double));
else
cost = 1.0;
xfprintf(fp, "a %d %d %.*g\n",
a->tail->i, a->head->i, 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;
}
/***********************************************************************
* NAME
*
* glp_read_ccdata - read graph in DIMACS clique/coloring format
*
* SYNOPSIS
*
* int glp_read_ccdata(glp_graph *G, int v_wgt, const char *fname);
*
* DESCRIPTION
*
* The routine glp_read_ccdata reads an (undirected) graph in DIMACS
* clique/coloring format from 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_read_ccdata(glp_graph *G, int v_wgt, const char *fname)
{ struct csa _csa, *csa = &_csa;
glp_vertex *v;
int i, j, k, nv, ne, ret = 0;
double w;
char *flag = NULL;
if (v_wgt >= 0 && v_wgt > G->v_size - (int)sizeof(double))
xerror("glp_read_ccdata: v_wgt = %d; invalid offset\n",
v_wgt);
glp_erase_graph(G, G->v_size, G->a_size);
if (setjmp(csa->jump))
{ ret = 1;
goto done;
}
csa->fname = fname;
csa->fp = NULL;
csa->count = 0;
csa->c = '\n';
csa->field[0] = '\0';
csa->empty = csa->nonint = 0;
xprintf("Reading graph from `%s'...\n", fname);
csa->fp = glp_open(fname, "r");
if (csa->fp == NULL)
{ xprintf("Unable to open `%s' - %s\n", fname, get_err_msg());
longjmp(csa->jump, 1);
}
/* read problem line */
read_designator(csa);
if (strcmp(csa->field, "p") != 0)
error(csa, "problem line missing or invalid");
read_field(csa);
if (strcmp(csa->field, "edge") != 0)
error(csa, "wrong problem designator; `edge' expected");
read_field(csa);
if (!(str2int(csa->field, &nv) == 0 && nv >= 0))
error(csa, "number of vertices missing or invalid");
read_field(csa);
if (!(str2int(csa->field, &ne) == 0 && ne >= 0))
error(csa, "number of edges missing or invalid");
xprintf("Graph has %d vert%s and %d edge%s\n",
nv, nv == 1 ? "ex" : "ices", ne, ne == 1 ? "" : "s");
if (nv > 0) glp_add_vertices(G, nv);
end_of_line(csa);
/* read node descriptor lines */
flag = xcalloc(1+nv, sizeof(char));
memset(&flag[1], 0, nv * sizeof(char));
if (v_wgt >= 0)
{ w = 1.0;
for (i = 1; i <= nv; i++)
{ v = G->v[i];
memcpy((char *)v->data + v_wgt, &w, sizeof(double));
}
}
for (;;)
{ read_designator(csa);
if (strcmp(csa->field, "n") != 0) break;
read_field(csa);
if (str2int(csa->field, &i) != 0)
error(csa, "vertex number missing or invalid");
if (!(1 <= i && i <= nv))
error(csa, "vertex number %d out of range", i);
if (flag[i])
error(csa, "duplicate descriptor of vertex %d", i);
read_field(csa);
if (str2num(csa->field, &w) != 0)
error(csa, "vertex weight missing or invalid");
check_int(csa, w);
if (v_wgt >= 0)
{ v = G->v[i];
memcpy((char *)v->data + v_wgt, &w, sizeof(double));
}
flag[i] = 1;
end_of_line(csa);
}
xfree(flag), flag = NULL;
/* read edge descriptor lines */
for (k = 1; k <= ne; k++)
{ if (k > 1) read_designator(csa);
if (strcmp(csa->field, "e") != 0)
error(csa, "wrong line designator; `e' expected");
read_field(csa);
if (str2int(csa->field, &i) != 0)
error(csa, "first vertex number missing or invalid");
if (!(1 <= i && i <= nv))
error(csa, "first vertex number %d out of range", i);
read_field(csa);
if (str2int(csa->field, &j) != 0)
error(csa, "second vertex number missing or invalid");
if (!(1 <= j && j <= nv))
error(csa, "second vertex number %d out of range", j);
glp_add_arc(G, i, j);
end_of_line(csa);
}
xprintf("%d lines were read\n", csa->count);
done: if (ret) glp_erase_graph(G, G->v_size, G->a_size);
if (csa->fp != NULL) glp_close(csa->fp);
if (flag != NULL) xfree(flag);
return ret;
}
/***********************************************************************
* NAME
*
* glp_write_ccdata - write graph in DIMACS clique/coloring format
*
* SYNOPSIS
*
* int glp_write_ccdata(glp_graph *G, int v_wgt, const char *fname);
*
* DESCRIPTION
*
* The routine glp_write_ccdata writes the specified graph in DIMACS
* clique/coloring 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_ccdata(glp_graph *G, int v_wgt, const char *fname)
{ glp_file *fp;
glp_vertex *v;
glp_arc *e;
int i, count = 0, ret;
double w;
if (v_wgt >= 0 && v_wgt > G->v_size - (int)sizeof(double))
xerror("glp_write_ccdata: v_wgt = %d; invalid offset\n",
v_wgt);
xprintf("Writing graph 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 edge %d %d\n", G->nv, G->na), count++;
if (v_wgt >= 0)
{ for (i = 1; i <= G->nv; i++)
{ v = G->v[i];
memcpy(&w, (char *)v->data + v_wgt, sizeof(double));
if (w != 1.0)
xfprintf(fp, "n %d %.*g\n", i, DBL_DIG, w), count++;
}
}
for (i = 1; i <= G->nv; i++)
{ v = G->v[i];
for (e = v->out; e != NULL; e = e->t_next)
xfprintf(fp, "e %d %d\n", e->tail->i, e->head->i), 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;
}
/***********************************************************************
* NAME
*
* glp_read_prob - read problem data in GLPK format
*
* SYNOPSIS
*
* int glp_read_prob(glp_prob *P, int flags, const char *fname);
*
* The routine glp_read_prob reads problem data in GLPK LP/MIP format
* from 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_read_prob(glp_prob *P, int flags, const char *fname)
{ struct csa _csa, *csa = &_csa;
int mip, m, n, nnz, ne, i, j, k, type, kind, ret, *ln = NULL,
*ia = NULL, *ja = NULL;
double lb, ub, temp, *ar = NULL;
char *rf = NULL, *cf = NULL;
if (P == NULL || P->magic != GLP_PROB_MAGIC)
xerror("glp_read_prob: P = %p; invalid problem object\n",
P);
if (flags != 0)
xerror("glp_read_prob: flags = %d; invalid parameter\n",
flags);
if (fname == NULL)
xerror("glp_read_prob: fname = %d; invalid parameter\n",
fname);
glp_erase_prob(P);
if (setjmp(csa->jump))
{ ret = 1;
goto done;
}
csa->fname = fname;
csa->fp = NULL;
csa->count = 0;
csa->c = '\n';
csa->field[0] = '\0';
csa->empty = csa->nonint = 0;
xprintf("Reading problem data from `%s'...\n", fname);
csa->fp = glp_open(fname, "r");
if (csa->fp == NULL)
{ xprintf("Unable to open `%s' - %s\n", fname, get_err_msg());
longjmp(csa->jump, 1);
}
/* read problem line */
read_designator(csa);
if (strcmp(csa->field, "p") != 0)
error(csa, "problem line missing or invalid");
read_field(csa);
if (strcmp(csa->field, "lp") == 0)
mip = 0;
else if (strcmp(csa->field, "mip") == 0)
mip = 1;
else
error(csa, "wrong problem designator; `lp' or `mip' expected\n"
);
read_field(csa);
if (strcmp(csa->field, "min") == 0)
glp_set_obj_dir(P, GLP_MIN);
else if (strcmp(csa->field, "max") == 0)
glp_set_obj_dir(P, GLP_MAX);
else
error(csa, "objective sense missing or invalid");
read_field(csa);
if (!(str2int(csa->field, &m) == 0 && m >= 0))
error(csa, "number of rows missing or invalid");
read_field(csa);
if (!(str2int(csa->field, &n) == 0 && n >= 0))
error(csa, "number of columns missing or invalid");
read_field(csa);
if (!(str2int(csa->field, &nnz) == 0 && nnz >= 0))
error(csa, "number of constraint coefficients missing or inval"
"id");
if (m > 0)
{ glp_add_rows(P, m);
for (i = 1; i <= m; i++)
glp_set_row_bnds(P, i, GLP_FX, 0.0, 0.0);
}
if (n > 0)
{ glp_add_cols(P, n);
for (j = 1; j <= n; j++)
{ if (!mip)
glp_set_col_bnds(P, j, GLP_LO, 0.0, 0.0);
else
glp_set_col_kind(P, j, GLP_BV);
}
}
end_of_line(csa);
/* allocate working arrays */
rf = xcalloc(1+m, sizeof(char));
memset(rf, 0, 1+m);
cf = xcalloc(1+n, sizeof(char));
memset(cf, 0, 1+n);
ln = xcalloc(1+nnz, sizeof(int));
ia = xcalloc(1+nnz, sizeof(int));
ja = xcalloc(1+nnz, sizeof(int));
ar = xcalloc(1+nnz, sizeof(double));
/* read descriptor lines */
ne = 0;
for (;;)
{ read_designator(csa);
if (strcmp(csa->field, "i") == 0)
{ /* row descriptor */
read_field(csa);
if (str2int(csa->field, &i) != 0)
error(csa, "row number missing or invalid");
if (!(1 <= i && i <= m))
error(csa, "row number out of range");
read_field(csa);
if (strcmp(csa->field, "f") == 0)
type = GLP_FR;
else if (strcmp(csa->field, "l") == 0)
type = GLP_LO;
else if (strcmp(csa->field, "u") == 0)
type = GLP_UP;
else if (strcmp(csa->field, "d") == 0)
type = GLP_DB;
else if (strcmp(csa->field, "s") == 0)
type = GLP_FX;
else
error(csa, "row type missing or invalid");
if (type == GLP_LO || type == GLP_DB || type == GLP_FX)
{ read_field(csa);
if (str2num(csa->field, &lb) != 0)
error(csa, "row lower bound/fixed value missing or in"
"valid");
}
else
lb = 0.0;
if (type == GLP_UP || type == GLP_DB)
{ read_field(csa);
if (str2num(csa->field, &ub) != 0)
error(csa, "row upper bound missing or invalid");
}
else
ub = 0.0;
if (rf[i] & 0x01)
error(csa, "duplicate row descriptor");
glp_set_row_bnds(P, i, type, lb, ub), rf[i] |= 0x01;
}
else if (strcmp(csa->field, "j") == 0)
{ /* column descriptor */
read_field(csa);
if (str2int(csa->field, &j) != 0)
error(csa, "column number missing or invalid");
if (!(1 <= j && j <= n))
error(csa, "column number out of range");
if (!mip)
kind = GLP_CV;
else
{ read_field(csa);
if (strcmp(csa->field, "c") == 0)
kind = GLP_CV;
else if (strcmp(csa->field, "i") == 0)
kind = GLP_IV;
else if (strcmp(csa->field, "b") == 0)
{ kind = GLP_IV;
type = GLP_DB, lb = 0.0, ub = 1.0;
goto skip;
}
else
error(csa, "column kind missing or invalid");
}
read_field(csa);
if (strcmp(csa->field, "f") == 0)
type = GLP_FR;
else if (strcmp(csa->field, "l") == 0)
type = GLP_LO;
else if (strcmp(csa->field, "u") == 0)
type = GLP_UP;
else if (strcmp(csa->field, "d") == 0)
type = GLP_DB;
else if (strcmp(csa->field, "s") == 0)
type = GLP_FX;
else
error(csa, "column type missing or invalid");
if (type == GLP_LO || type == GLP_DB || type == GLP_FX)
{ read_field(csa);
if (str2num(csa->field, &lb) != 0)
error(csa, "column lower bound/fixed value missing or"
" invalid");
}
else
lb = 0.0;
if (type == GLP_UP || type == GLP_DB)
{ read_field(csa);
if (str2num(csa->field, &ub) != 0)
error(csa, "column upper bound missing or invalid");
}
else
ub = 0.0;
skip: if (cf[j] & 0x01)
error(csa, "duplicate column descriptor");
glp_set_col_kind(P, j, kind);
glp_set_col_bnds(P, j, type, lb, ub), cf[j] |= 0x01;
}
else if (strcmp(csa->field, "a") == 0)
{ /* coefficient descriptor */
read_field(csa);
if (str2int(csa->field, &i) != 0)
error(csa, "row number missing or invalid");
if (!(0 <= i && i <= m))
error(csa, "row number out of range");
read_field(csa);
if (str2int(csa->field, &j) != 0)
error(csa, "column number missing or invalid");
if (!((i == 0 ? 0 : 1) <= j && j <= n))
error(csa, "column number out of range");
read_field(csa);
if (i == 0)
{ if (str2num(csa->field, &temp) != 0)
error(csa, "objective %s missing or invalid",
j == 0 ? "constant term" : "coefficient");
if (cf[j] & 0x10)
error(csa, "duplicate objective %s",
j == 0 ? "constant term" : "coefficient");
glp_set_obj_coef(P, j, temp), cf[j] |= 0x10;
}
else
{ if (str2num(csa->field, &temp) != 0)
error(csa, "constraint coefficient missing or invalid"
);
if (ne == nnz)
error(csa, "too many constraint coefficient descripto"
"rs");
ln[++ne] = csa->count;
ia[ne] = i, ja[ne] = j, ar[ne] = temp;
}
}
else if (strcmp(csa->field, "n") == 0)
{ /* symbolic name descriptor */
read_field(csa);
if (strcmp(csa->field, "p") == 0)
{ /* problem name */
read_field(csa);
if (P->name != NULL)
error(csa, "duplicate problem name");
glp_set_prob_name(P, csa->field);
}
else if (strcmp(csa->field, "z") == 0)
{ /* objective name */
read_field(csa);
if (P->obj != NULL)
error(csa, "duplicate objective name");
glp_set_obj_name(P, csa->field);
}
else if (strcmp(csa->field, "i") == 0)
{ /* row name */
read_field(csa);
if (str2int(csa->field, &i) != 0)
error(csa, "row number missing or invalid");
if (!(1 <= i && i <= m))
error(csa, "row number out of range");
read_field(csa);
if (P->row[i]->name != NULL)
error(csa, "duplicate row name");
glp_set_row_name(P, i, csa->field);
}
else if (strcmp(csa->field, "j") == 0)
{ /* column name */
read_field(csa);
if (str2int(csa->field, &j) != 0)
error(csa, "column number missing or invalid");
if (!(1 <= j && j <= n))
error(csa, "column number out of range");
read_field(csa);
if (P->col[j]->name != NULL)
error(csa, "duplicate column name");
glp_set_col_name(P, j, csa->field);
}
else
error(csa, "object designator missing or invalid");
}
else if (strcmp(csa->field, "e") == 0)
break;
else
error(csa, "line designator missing or invalid");
end_of_line(csa);
}
if (ne < nnz)
error(csa, "too few constraint coefficient descriptors");
xassert(ne == nnz);
k = glp_check_dup(m, n, ne, ia, ja);
xassert(0 <= k && k <= nnz);
if (k > 0)
{ csa->count = ln[k];
error(csa, "duplicate constraint coefficient");
}
glp_load_matrix(P, ne, ia, ja, ar);
/* print some statistics */
if (P->name != NULL)
xprintf("Problem: %s\n", P->name);
if (P->obj != NULL)
xprintf("Objective: %s\n", P->obj);
xprintf("%d row%s, %d column%s, %d non-zero%s\n",
m, m == 1 ? "" : "s", n, n == 1 ? "" : "s", nnz, nnz == 1 ?
"" : "s");
if (glp_get_num_int(P) > 0)
{ int ni = glp_get_num_int(P);
int nb = glp_get_num_bin(P);
if (ni == 1)
{ if (nb == 0)
xprintf("One variable is integer\n");
else
xprintf("One variable is binary\n");
}
else
{ xprintf("%d integer variables, ", ni);
if (nb == 0)
xprintf("none");
else if (nb == 1)
xprintf("one");
else if (nb == ni)
xprintf("all");
else
xprintf("%d", nb);
xprintf(" of which %s binary\n", nb == 1 ? "is" : "are");
}
}
xprintf("%d lines were read\n", csa->count);
/* problem data has been successfully read */
glp_sort_matrix(P);
ret = 0;
done: if (csa->fp != NULL) glp_close(csa->fp);
if (rf != NULL) xfree(rf);
if (cf != NULL) xfree(cf);
if (ln != NULL) xfree(ln);
if (ia != NULL) xfree(ia);
if (ja != NULL) xfree(ja);
if (ar != NULL) xfree(ar);
if (ret) glp_erase_prob(P);
return ret;
}
/***********************************************************************
* NAME
*
* glp_write_prob - write problem data in GLPK format
*
* SYNOPSIS
*
* int glp_write_prob(glp_prob *P, int flags, const char *fname);
*
* The routine glp_write_prob writes problem data in GLPK LP/MIP 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_prob(glp_prob *P, int flags, const char *fname)
{ glp_file *fp;
GLPROW *row;
GLPCOL *col;
GLPAIJ *aij;
int mip, i, j, count, ret;
if (P == NULL || P->magic != GLP_PROB_MAGIC)
xerror("glp_write_prob: P = %p; invalid problem object\n",
P);
if (flags != 0)
xerror("glp_write_prob: flags = %d; invalid parameter\n",
flags);
if (fname == NULL)
xerror("glp_write_prob: fname = %d; invalid parameter\n",
fname);
xprintf("Writing problem data to `%s'...\n", fname);
fp = glp_open(fname, "w"), count = 0;
if (fp == NULL)
{ xprintf("Unable to create `%s' - %s\n", fname, get_err_msg());
ret = 1;
goto done;
}
/* write problem line */
mip = (glp_get_num_int(P) > 0);
xfprintf(fp, "p %s %s %d %d %d\n", !mip ? "lp" : "mip",
P->dir == GLP_MIN ? "min" : P->dir == GLP_MAX ? "max" : "???",
P->m, P->n, P->nnz), count++;
if (P->name != NULL)
xfprintf(fp, "n p %s\n", P->name), count++;
if (P->obj != NULL)
xfprintf(fp, "n z %s\n", P->obj), count++;
/* write row descriptors */
for (i = 1; i <= P->m; i++)
{ row = P->row[i];
if (row->type == GLP_FX && row->lb == 0.0)
goto skip1;
xfprintf(fp, "i %d ", i), count++;
if (row->type == GLP_FR)
xfprintf(fp, "f\n");
else if (row->type == GLP_LO)
xfprintf(fp, "l %.*g\n", DBL_DIG, row->lb);
else if (row->type == GLP_UP)
xfprintf(fp, "u %.*g\n", DBL_DIG, row->ub);
else if (row->type == GLP_DB)
xfprintf(fp, "d %.*g %.*g\n", DBL_DIG, row->lb, DBL_DIG,
row->ub);
else if (row->type == GLP_FX)
xfprintf(fp, "s %.*g\n", DBL_DIG, row->lb);
else
xassert(row != row);
skip1: if (row->name != NULL)
xfprintf(fp, "n i %d %s\n", i, row->name), count++;
}
/* write column descriptors */
for (j = 1; j <= P->n; j++)
{ col = P->col[j];
if (!mip && col->type == GLP_LO && col->lb == 0.0)
goto skip2;
if (mip && col->kind == GLP_IV && col->type == GLP_DB &&
col->lb == 0.0 && col->ub == 1.0)
goto skip2;
xfprintf(fp, "j %d ", j), count++;
if (mip)
{ if (col->kind == GLP_CV)
xfprintf(fp, "c ");
else if (col->kind == GLP_IV)
xfprintf(fp, "i ");
else
xassert(col != col);
}
if (col->type == GLP_FR)
xfprintf(fp, "f\n");
else if (col->type == GLP_LO)
xfprintf(fp, "l %.*g\n", DBL_DIG, col->lb);
else if (col->type == GLP_UP)
xfprintf(fp, "u %.*g\n", DBL_DIG, col->ub);
else if (col->type == GLP_DB)
xfprintf(fp, "d %.*g %.*g\n", DBL_DIG, col->lb, DBL_DIG,
col->ub);
else if (col->type == GLP_FX)
xfprintf(fp, "s %.*g\n", DBL_DIG, col->lb);
else
xassert(col != col);
skip2: if (col->name != NULL)
xfprintf(fp, "n j %d %s\n", j, col->name), count++;
}
/* write objective coefficient descriptors */
if (P->c0 != 0.0)
xfprintf(fp, "a 0 0 %.*g\n", DBL_DIG, P->c0), count++;
for (j = 1; j <= P->n; j++)
{ col = P->col[j];
if (col->coef != 0.0)
xfprintf(fp, "a 0 %d %.*g\n", j, DBL_DIG, col->coef),
count++;
}
/* write constraint coefficient descriptors */
for (i = 1; i <= P->m; i++)
{ row = P->row[i];
for (aij = row->ptr; aij != NULL; aij = aij->r_next)
xfprintf(fp, "a %d %d %.*g\n", i, aij->col->j, DBL_DIG,
aij->val), count++;
}
/* write end line */
xfprintf(fp, "e o f\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;
}
/**********************************************************************/
int glp_read_cnfsat(glp_prob *P, const char *fname)
{ /* read CNF-SAT problem data in DIMACS format */
struct csa _csa, *csa = &_csa;
int m, n, i, j, len, neg, rhs, ret = 0, *ind = NULL;
double *val = NULL;
char *map = NULL;
if (P == NULL || P->magic != GLP_PROB_MAGIC)
xerror("glp_read_cnfsat: P = %p; invalid problem object\n",
P);
if (fname == NULL)
xerror("glp_read_cnfsat: fname = %p; invalid parameter\n",
fname);
glp_erase_prob(P);
if (setjmp(csa->jump))
{ ret = 1;
goto done;
}
csa->fname = fname;
csa->fp = NULL;
csa->count = 0;
csa->c = '\n';
csa->field[0] = '\0';
csa->empty = csa->nonint = 0;
xprintf("Reading CNF-SAT problem data from `%s'...\n", fname);
csa->fp = glp_open(fname, "r");
if (csa->fp == NULL)
{ xprintf("Unable to open `%s' - %s\n", fname, get_err_msg());
longjmp(csa->jump, 1);
}
/* read problem line */
read_designator(csa);
if (strcmp(csa->field, "p") != 0)
error(csa, "problem line missing or invalid");
read_field(csa);
if (strcmp(csa->field, "cnf") != 0)
error(csa, "wrong problem designator; `cnf' expected\n");
read_field(csa);
if (!(str2int(csa->field, &n) == 0 && n >= 0))
error(csa, "number of variables missing or invalid\n");
read_field(csa);
if (!(str2int(csa->field, &m) == 0 && m >= 0))
error(csa, "number of clauses missing or invalid\n");
xprintf("Instance has %d variable%s and %d clause%s\n",
n, n == 1 ? "" : "s", m, m == 1 ? "" : "s");
end_of_line(csa);
if (m > 0)
glp_add_rows(P, m);
if (n > 0)
{ glp_add_cols(P, n);
for (j = 1; j <= n; j++)
glp_set_col_kind(P, j, GLP_BV);
}
/* allocate working arrays */
ind = xcalloc(1+n, sizeof(int));
val = xcalloc(1+n, sizeof(double));
map = xcalloc(1+n, sizeof(char));
for (j = 1; j <= n; j++) map[j] = 0;
/* read clauses */
for (i = 1; i <= m; i++)
{ /* read i-th clause */
len = 0, rhs = 1;
for (;;)
{ /* skip white-space characters */
while (csa->c == ' ' || csa->c == '\n')
read_char(csa);
/* read term */
read_field(csa);
if (str2int(csa->field, &j) != 0)
error(csa, "variable number missing or invalid\n");
if (j > 0)
neg = 0;
else if (j < 0)
neg = 1, j = -j, rhs--;
else
break;
if (!(1 <= j && j <= n))
error(csa, "variable number out of range\n");
if (map[j])
error(csa, "duplicate variable number\n");
len++, ind[len] = j, val[len] = (neg ? -1.0 : +1.0);
map[j] = 1;
}
glp_set_row_bnds(P, i, GLP_LO, (double)rhs, 0.0);
glp_set_mat_row(P, i, len, ind, val);
while (len > 0) map[ind[len--]] = 0;
}
xprintf("%d lines were read\n", csa->count);
/* problem data has been successfully read */
glp_sort_matrix(P);
done: if (csa->fp != NULL) glp_close(csa->fp);
if (ind != NULL) xfree(ind);
if (val != NULL) xfree(val);
if (map != NULL) xfree(map);
if (ret) glp_erase_prob(P);
return ret;
}
/**********************************************************************/
int glp_check_cnfsat(glp_prob *P)
{ /* check for CNF-SAT problem instance */
int m = P->m;
int n = P->n;
GLPROW *row;
GLPCOL *col;
GLPAIJ *aij;
int i, j, neg;
if (P == NULL || P->magic != GLP_PROB_MAGIC)
xerror("glp_check_cnfsat: P = %p; invalid problem object\n",
P);
/* check columns */
for (j = 1; j <= n; j++)
{ col = P->col[j];
/* the variable should be binary */
if (!(col->kind == GLP_IV && col->type == GLP_DB &&
col->lb == 0.0 && col->ub == 1.0))
return 1;
}
/* objective function should be zero */
if (P->c0 != 0.0)
return 2;
for (j = 1; j <= n; j++)
{ col = P->col[j];
if (col->coef != 0.0)
return 3;
}
/* check rows */
for (i = 1; i <= m; i++)
{ row = P->row[i];
/* the row should be of ">=" type */
if (row->type != GLP_LO)
return 4;
/* check constraint coefficients */
neg = 0;
for (aij = row->ptr; aij != NULL; aij = aij->r_next)
{ /* the constraint coefficient should be +1 or -1 */
if (aij->val == +1.0)
;
else if (aij->val == -1.0)
neg++;
else
return 5;
}
/* the right-hand side should be (1 - neg), where neg is the
number of negative constraint coefficients in the row */
if (row->lb != (double)(1 - neg))
return 6;
}
/* congratulations; this is CNF-SAT */
return 0;
}
/**********************************************************************/
int glp_write_cnfsat(glp_prob *P, const char *fname)
{ /* write CNF-SAT problem data in DIMACS format */
glp_file *fp = NULL;
GLPAIJ *aij;
int i, j, len, count = 0, ret;
char s[50];
if (P == NULL || P->magic != GLP_PROB_MAGIC)
xerror("glp_write_cnfsat: P = %p; invalid problem object\n",
P);
if (glp_check_cnfsat(P) != 0)
{ xprintf("glp_write_cnfsat: problem object does not encode CNF-"
"SAT instance\n");
ret = 1;
goto done;
}
xprintf("Writing CNF-SAT 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",
P->name == NULL ? "unknown" : P->name), count++;
xfprintf(fp, "p cnf %d %d\n", P->n, P->m), count++;
for (i = 1; i <= P->m; i++)
{ len = 0;
for (aij = P->row[i]->ptr; aij != NULL; aij = aij->r_next)
{ j = aij->col->j;
if (aij->val < 0.0) j = -j;
sprintf(s, "%d", j);
if (len > 0 && len + 1 + strlen(s) > 72)
xfprintf(fp, "\n"), count++, len = 0;
xfprintf(fp, "%s%s", len == 0 ? "" : " ", s);
if (len > 0) len++;
len += strlen(s);
}
if (len > 0 && len + 1 + 1 > 72)
xfprintf(fp, "\n"), count++, len = 0;
xfprintf(fp, "%s0\n", len == 0 ? "" : " "), 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 */