/* rdprob.c (read problem data in GLPK format) */
/***********************************************************************
* This code is part of GLPK (GNU Linear Programming Kit).
* Copyright (C) 2010-2016 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 "dimacs.h"
#include "misc.h"
#include "prob.h"
#define xfprintf glp_format
#define error dmx_error
#define warning dmx_warning
#define read_char dmx_read_char
#define read_designator dmx_read_designator
#define read_field dmx_read_field
#define end_of_line dmx_end_of_line
#define check_int dmx_check_int
/***********************************************************************
* 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)
{ DMX _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 0 /* 04/IV-2016 */
if (P == NULL || P->magic != GLP_PROB_MAGIC)
xerror("glp_read_prob: P = %p; invalid problem object\n",
P);
#endif
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");
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;
}
/* eof */