static void parse_constraints(struct csa *csa)
{ int i, len, type;
double s;
/* parse the keyword 'subject to' */
xassert(csa->token == T_SUBJECT_TO);
scan_token(csa);
loop: /* create new row (constraint) */
i = glp_add_rows(csa->P, 1);
/* parse row name */
if (csa->token == T_NAME && csa->c == ':')
{ /* row name is followed by a colon */
if (glp_find_row(csa->P, csa->image) != 0)
error(csa, "constraint '%s' multiply defined\n",
csa->image);
glp_set_row_name(csa->P, i, csa->image);
scan_token(csa);
xassert(csa->token == T_COLON);
scan_token(csa);
}
else
{ /* row name is not specified; use default */
char name[50];
sprintf(name, "r.%d", csa->count);
glp_set_row_name(csa->P, i, name);
}
/* parse linear form */
len = parse_linear_form(csa);
glp_set_mat_row(csa->P, i, len, csa->ind, csa->val);
/* parse constraint sense */
if (csa->token == T_LE)
type = GLP_UP, scan_token(csa);
else if (csa->token == T_GE)
type = GLP_LO, scan_token(csa);
else if (csa->token == T_EQ)
type = GLP_FX, scan_token(csa);
else
error(csa, "missing constraint sense\n");
/* parse right-hand side */
if (csa->token == T_PLUS)
s = +1.0, scan_token(csa);
else if (csa->token == T_MINUS)
s = -1.0, scan_token(csa);
else
s = +1.0;
if (csa->token != T_NUMBER)
error(csa, "missing right-hand side\n");
glp_set_row_bnds(csa->P, i, type, s * csa->value, s * csa->value);
/* the rest of the current line must be empty */
if (!(csa->c == '\n' || csa->c == EOF))
error(csa, "invalid symbol(s) beyond right-hand side\n");
scan_token(csa);
/* if the next token is a sign, numeric constant, or a symbolic
name, here is another constraint */
if (csa->token == T_PLUS || csa->token == T_MINUS ||
csa->token == T_NUMBER || csa->token == T_NAME) goto loop;
return;
}
int lpx_find_row(LPX *lp, const char *name)
{ /* find row by its name */
return glp_find_row(lp, name);
}
int c_glp_find_row(glp_prob *lp, const char *name){
return glp_find_row(lp, name);
}
