RE: [Help-glpk] Getting more info from presolver

[Joey Rios]

> > So this brings me to
> > the hope that the glpk presolver could offer more insight about which
> > constraints it finds unsatisfiable.  Even if it told me one of them,
> > it would be a great clue for my debugging.  If there is a way to do
> > this through the API (vs. glpsol), that's fine too.
>
> You may look at the output listing produced by either glpsol (with
> -o option) or the api routine lpx_print_sol.
> ...
> Note that on running glpsol you need to disable the lp presolver
> (--nopresol), because it is unable to recover non-optimal solutions.
>

Thanks for the response Andrew.  I had read this method of getting information in one of the previous threads, but was hoping for another (faster) way.  My problem is very large.  As in "can take several days to solve" large.  The presolver figures out quite quickly, however, that the instance is primal infeasible.  Was hoping that it could give me some clues before going forward with the fix described here.  Anyway, thanks again.

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