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Re: Mathematica 5: Integration bug in quadratic found by the GEMM machine

• To: mathgroup at smc.vnet.net
• Subject: [mg46982] Re: Mathematica 5: Integration bug in quadratic found by the GEMM machine
• From: ankowar at yahoo.com (Andy Kowar)
• Date: Thu, 18 Mar 2004 01:25:19 -0500 (EST)
• References: <200403150454.XAA16166@smc.vnet.net> <c36avb$s0i$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

Andrzej Kozlowski <akoz at mimuw.edu.pl> wrote in message news:<c36avb$s0i$1 at smc.vnet.net>...
> Well, I hope that these are mostly "machine generated bugs". The 
> problem with this sort of approach of course is that you can take just 
> one genuine bug in, say, integration, and then by varying the input in 
> various ways generate 10, 100 or 10000 additional "bugs". Whenever I 
> hear of a "massive flow of bugs" I suspect something like this at work.

On the bright side a developer spends time to fix one genuine bug but
can claim eliminating 10000.:-)

AK

> 
> Andrzej
> 
> 
> On 15 Mar 2004, at 05:54, Vladimir Bondarenko wrote:
> 
> > Hello,
> >
> > Here is, just of pure curiosity, a sample from my GEMM machine:
> >
> >
> > $Version
> >
> > 5.0 for Microsoft Windows (June 11, 2003)
> >
> > Integrate[1/(-2 z^2 + 3 z - 1), {z, -1, 0}]
> >
> > Log[3/2]     // invalid answer
> >
> > 0.405465
> >
> > NIntegrate[1/(-2*z^2 + 3*z - 1), {z, -1, 0}]
> >
> > -0.405465
> >
> >
> > But the above is just a good opportunity: actually, ' am writing
> > here to announce the next good piece of news: a massive flow of
> > never published bug reports on a certain system is coming within
> > several next days after which we will operate at a new level
> > of speed; he who watches the activity knows well what I mean.
> >
> >
> > Best wishes,
> >
> > Vladimir Bondarenko
> >
> > http://www.cybertester.com/
> > http://www.CAS-testing.org/
> >
> >

• References:
  • Mathematica 5: Integration bug in quadratic found by the GEMM machine
    • From: Vladimir Bondarenko <vvb@mail.strace.net>