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Re: [Help-glpk] glpksol default settings
From: |
Andrew Makhorin |
Subject: |
Re: [Help-glpk] glpksol default settings |
Date: |
Tue, 29 Jul 2008 17:05:53 +0400 |
> Thanks, I changed it and I can kind of reproduce glpsol's behaviour,
> but now I pinpointed the problem to this LP:
> http://www.mimuw.edu.pl/~mucha/lpQ_bad.txt
> glpsol --cpxlp lpQ_bad.txt
> give UNBOUNDED solution here. However, both
> glpsol --std --cpxlp lpQ_bad.txt
> and
> glpsol --adv --cpxlp lpQ_bad.txt
> which is kind of weird.
Probably this happens because your instance is not well conditioned,
so due to excessive round-off errors the presolved lp is unbounded
while the original lp is not.
> Also neither lpx_adv_basis nor lpx_std_basis
> seem to solve the problem from C++ API level. Could anyone please tell
> me what I am missing here?
Could you provide the code returned by glp_simplex?
- [Help-glpk] glpksol default settings, Marcin Mucha, 2008/07/29
- Re: [Help-glpk] glpksol default settings, Andrew Makhorin, 2008/07/29
- Re: [Help-glpk] glpksol default settings, Marcin Mucha, 2008/07/29
- Re: [Help-glpk] glpksol default settings,
Andrew Makhorin <=
- Re: [Help-glpk] glpksol default settings, Marcin Mucha, 2008/07/29
- Re: [Help-glpk] glpksol default settings, Andrew Makhorin, 2008/07/29
- Re: [Help-glpk] glpksol default settings, Marcin Mucha, 2008/07/29
- Re: [Help-glpk] glpksol default settings, Haroldo Santos, 2008/07/29
- Re: [Help-glpk] glpksol default settings, Andrew Makhorin, 2008/07/30
- Re: [Help-glpk] glpksol default settings, Marcin Mucha, 2008/07/30
- Re: [Help-glpk] glpksol default settings, Andrew Makhorin, 2008/07/31