Hello Edd ------------------------------------------------------------ To: Robbie Morrison <[email protected]> Subject: Re: [Help-glpk] glpsol, arbitrary precision and large numbers Message-ID: <[email protected]> From: Edd Barrett <[email protected]> Date: Fri, 29 Jun 2012 18:57:34 +0100 ------------------------------------------------------------
> On Sat, Jun 30, 2012 at 04:34:19AM +1200, Robbie Morrison wrote: [snip] > Ah, I am failing the KKT.PB check. From the .sol file > I attached in my earlier mail: > > ---8<--- > Integer feasibility conditions: > > KKT.PE: max.abs.err = 0.00e+00 on row 0 > max.rel.err = 0.00e+00 on row 0 > High quality > > KKT.PB: max.abs.err = 5.00e+00 on row 15 > max.rel.err = 1.00e+00 on row 15 > SOLUTION IS INFEASIBLE > ---8<--- Yeh, I saw that earlier too. > So I guess the result is unreliable. I will have to > read into this more. The information in the wikibook I mentioned earlier might be a good place to start: http://en.wikibooks.org/wiki/GLPK/Solution_information#Karush-Kuhn-Tucker_optimality_conditions More KKT theory here too: http://en.wikibooks.org/wiki/GLPK/Background_theory#Karush-Kahn-Tucker_.28KKT.29_optimality_conditions I think richer return codes from GLPSOL could help in these kind of cases. That said, I use the API and can easily get this information programmatically. > Cheers for everyone's help. good luck with the bug hunt, Robbie --- Robbie Morrison PhD student -- policy-oriented energy system simulation Technical University of Berlin (TU-Berlin), Germany University email (redirected) : [email protected] Webmail (preferred) : [email protected] [from Webmail client] _______________________________________________ Help-glpk mailing list [email protected] https://lists.gnu.org/mailman/listinfo/help-glpk
