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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] Precision in Cholesky Decomposition
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Mon, 8 Jun 2009 17:45:55 +0200
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OK, cool! I hope you can stay on the development branch because that
would be quite heavy to backport.
Benoit
2009/6/8 Scott Stephens <stephens.js@xxxxxxxxx>:
> The development branch works! Thanks for the tip Benoit.
>
> On Mon, Jun 8, 2009 at 9:44 AM, Benoit Jacob<jacob.benoit.1@xxxxxxxxx> wrote:
>> 2009/6/8 Scott Stephens <stephens.js@xxxxxxxxx>:
>>> I am using Eigen 2.0.2; I will try the development branch.
>>>
>>> I just double checked the precision necessary, and 1e-16 works, but
>>> 1e-15 does not. The condition number of the matrix is
>>> 2525609.87787008 (computed in MATLAB), so it would seem to be okay by
>>> your 1e15 criterion.
>>
>> Indeed, that's a very reasonable condition number for double
>> precision, so it just seems that you hit the problems that existed in
>> the LLT implementation in Eigen 2.0.
>>
>> Here's hoping that the development branch works for you! Keep us posted.
>>
>> Benoit
>>
>>
>>
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>
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