[Top][All Lists]

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

Re: [Bug-glpk] Fpump

From: Andrew Makhorin
Subject: Re: [Bug-glpk] Fpump
Date: Mon, 17 Jun 2013 23:56:06 +0400

> there is something in your code that I can't explain.
> The first thing is that I added a loop counter (a double variable = 0
> and a loop++ command) and a xprintf to see the loops and the numerical
> instability disappeared. Well, this seems very strange.

I found the bug that causes numerical instability. A long time ago
Xypron fixed some my bug by adding a fragment to reoptimize lp, however,
he changes column types directly in the glp_prob object, and this leads
to inconsistency, because column statuses are not changed appropriately.
Glp_simplex does not check that assuming that all information in
glp_prob is correct. Will fix this bug in the next release.

reply via email to

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