Re: [Help-glpk] Preprocessing - Interior Point Method

[glpk xypron]

Hello Andrew,

How is the presolver invoked for the interior point method?
There is no field in glp_iptcp for this purpose.

> It is important to
> make sure that all basic solution components (statuses, primal and dual
> values) are recovered correctly.

I will have to add the code for pushing the transformation
on the transformation stack (npp_push_tse()) and to recover.

This is missing in the current version.

Best regards

Xypron

-------- Original-Nachricht --------
> Datum: Sat, 16 Oct 2010 01:12:50 +0400
> Betreff: Re: [Help-glpk] Preprocessing

> Hi Xypron,
> 
> > I implemented an elimination of linear dependent rows in appended
> > glpnpp06.c.
> > 
> > This cuts the solution time for Kevin's problem down from several
> > hours to 9 minutes.
> 
> Great! Did you intensively test that transformation? It is important to
> make sure that all basic solution components (statuses, primal and dual
> values) are recovered correctly. Besides, can it be applied to interior
> point and mip solutions?
> 
> 
> Andrew Makhorin
> 
> 

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