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From: Robert Kern <robert.kern@gmail.com>
Subject: Re: Simplex Algorithm
Date: Mon, 02 Sep 2013 10:55:43 +0100
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On 2013-09-02 02:26, Tommy Vee wrote:
> Anyone know where I can get an easy to use Python class or algorithm for the
> Simplex optimization algorithm?  I've tried the one in the link below, but I
> can't figure out if a) I'm using it properly, or b) where to get the solution.
> BTW, I tried some test scenarios using MS Excel's "Solver" and just can't get
> this algorithm to match Excel's results (which is spot on).
>
> http://taw9.hubpages.com/hub/Simplex-Algorithm-in-Python
>
> BTW, if I can't something to work, I'm going to be forced to use the VBA
> programmatic Excel interface. That wouldn't be too bad, but the data comes from
> a DB and getting it properly positioned to use Excel's "Solver" is very
> painful.  A Python approach would be much cleaner.

Can you show some of the test scenarios that you tried? There are different 
conventions in how to represent a linear programming problem, and different 
solvers may choose different conventions. You may have to convert between 
representations.

You may have better luck with the PuLP interface:

   https://pypi.python.org/pypi/PuLP

PuLP itself is just a modelling language rather than a solver, but the sources 
do contain compiled binaries for the CoinMP solver so it will work out-of-box on 
popular platforms, like Windows.

   https://projects.coin-or.org/CoinMP

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco