Re: [Help-glpk] spx_simplex

[Andrew Makhorin]

> what is this ???
> 
> spx_simplex : double-bounded variable 391 has invalid bounds
> 
> I dont undestand

This message means that you set both lower and upper bounds using

   lpx_set_row_bnds(lp, i, LPX_DB, lb, ub);

or

   lpx_set_col_bnds(lp, j, LPX_DB, lb, ub);

and lb >= ub while lb must be strictly less than ub. Note that
this error is detected by lpx_simplex, not by lpx_set_xxx_bnds.

Variables are numbered as x[1], ..., x[m], x[m+1], ..., x[m+n],
where m is the number or rows, n is number of the columns.