RE: [Help-glpk] DIMACS, mincost and GLPSOL

[Meketon, Marc]

I had a modified form of Andrew Goldberg's CS2 on my laptop (I bought a license 
many years ago) which supposedly is a better version of RELAX-IV.

My modification had taken out the ability to read DIMACs, but I had some time 
to kill in the last hour and reinstalled that ability.

On my problem that took about 30 minutes with the out-of-kilter algorithm in 
GLPK (and about 170 minutes with the GLPK simplex), CS2 took 7 seconds.  Whew.

-----Original Message-----
From: Andrew Makhorin [mailto:address@hidden
Sent: Wednesday, April 06, 2011 11:44 AM
To: Meketon, Marc
Cc: 'address@hidden'
Subject: RE: [Help-glpk] DIMACS, mincost and GLPSOL


> Your example on Page 35 is even better.

That is what I meant, not that one on p.32. Sorry.

>
> Roughly, the out-of-kilter ran about 5 times faster than the simplex
> for the same problem, and took about 2/3rd's the memory.

I'd like to note that today the out-of-kilter algorithm is not a best one for 
solving mincost. For example, RELAX-IV developed by Prof. Bertsekas is much 
faster (even faster that the network simplex). It is free software, so I plan 
to translate it to C and include in glpk as a better alternative.



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