Re: GLPK/glpsol gives different objective values for mip/nomip

Chris Matrakidis <[email protected]> Tue, 6 Oct 2020 16:25:02 +0300

Newsgroups	gmane.comp.gnu.glpk
Message-ID	<CAEaJ3S4_-QzXbhsTDT7J10o=EYQ3UQD868L2GzqPWP7qmRM_gA@mail.gmail.com>

On Tue, 6 Oct 2020 at 16:15, Domingo Alvarez Duarte <[email protected]>
wrote:

> Testing GLPK with miplib2017 I noticed that GLPK/glpsol gives different
> values for LP objective funcion value when a MIP problem is given with
> the option --nomip , is this the expected behavior ?
>

Yes, this is expected. For a mip additional preprocessing is possible, a
trivial example is that integer variable bounds can be tightened to the
next integer.

Best Regards,

Chris Matrakidis