[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re[4]: [Help-glpk] proposal for gnu lp/mip low-level format

From: Andrew Makhorin
Subject: Re[4]: [Help-glpk] proposal for gnu lp/mip low-level format
Date: Thu, 29 Jul 2004 08:25:28 +0400

>> There was an idea to implement a "mathematically exact" version of the
>> simplex method which would perform all calculations in rational numbers
>I'm not suggesting that rationals be used internally.
>As you noted, multi-precision is too slow.

There is an exact lp solver, exlp, which is based on GNU MP library
and performs all computations in rational numbers:

(There are more things in heaven and earth, Horatio, ... :+).

And it looks like the solution time is not so pessimistic even for
real-world models (I'm attaching exlp's benchmarks for netlib).
The solver's output is just fanatstic:

$ ./exlp boeing2.mps
variables: 162
rows:      166
iteration count(degenerate): 95(36)
iteration count(degenerate): 57(25)
optimal value: -6239290250177881164363943/19806093083700000000000
size: 3/3

Andrew Makhorin

Attachment: bench-steepest-edge.
Description: Binary data

Attachment: bench-dual.
Description: Binary data

reply via email to

[Prev in Thread] Current Thread [Next in Thread]