[Coin-discuss] presolve IP

[Matthew Galati]

Cool! Clumsy is ok for my needs right now. I'll give it a try.

You mean there will be no offset? I.e., what if presolve fixes a variable to
1.0 and removes it, and it has nonzero cost?




Matt,
>
> This is a clumsy Cbc type reply.
>
> cbc xxxxx.mps -preprocess save -heuristic off -maxnode -1 -solve
>
> will save cbc-presolved model on presolved.mps
>
> The -heuristic off and -maxnode -1are there to make it stop as quickly as
> possible.
>
> The offset should be fine.
>
> John
>
>
>    *[Coin-discuss] presolve IP*
>  *Matthew Galati * to: coin-discuss 09/24/2009 02:34 PM
>
>    Sent by: *coin-discuss-bounces at list.coin-or.org*
>
>
>
>
> ------------------------------
>
>
>
> What is the simplest way to presolve an IP? I don't care about doing it in
> memory or even having any way to "unravel/postprocess" to get back to the
> original space.
>
> I simply want to:
>  (1) read an MPS file
>  (2) presolve it
>  (3) output a new MPS file (and perhaps an objective offset, so that I can
> check that I match up at end)
>
> Thanks,
> Matt_______________________________________________
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>
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