Path: news.mathworks.com!not-for-mail
From: "Bobby Cheng" <bcheng@mathworks.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Ill conditioned matrix makes linsolve crash
Date: Fri, 30 Oct 2009 13:43:18 -0400
Organization: The MathWorks, Inc.
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I have not done this myself as I can change this from the inside. :)

But I think you can track the report update and comment of the content. 
Again, I have not tried any on this.

I can assure you that it is the same issue in the bug report. I am 
investigating the issue and have added your matrix into our tests. So thank 
you for the test case.

---Bob.

"Sebastiaan " <s.breedveld@erasmusmc.REMOVE.BOO.BOO.nl> wrote in message 
news:hcebj2$7o5$1@fred.mathworks.com...
> "Bobby Cheng" <bcheng@mathworks.com> wrote in message 
> <hcdekc$bdc$1@fred.mathworks.com>...
>> http://www.mathworks.com/support/bugreports/search_results?search_executed=1&keyword=573283&release_filter=Exists+in&release=168&selected_products=&commit=Search
>>
>> See bug report 573283.
>>
> Wow, thank you!
>
> Is it possible to reply or ammend to a bug report? (I can only give 
> quality feedback...)
>
> The bugreport tells me:
> ----
> The functions ldl and inv may hang MATLAB when the input matrix meets all 
> of the following criteria:
>    * Hermitian
>    * ill-conditioned
>    * full
>    * the eigenvalues cluster around zero.
> ---
> It hangs with ldl and inv too, but the last criterion is not met. A few 
> (5) eigenvalues are in the order of 1, 33 in the order of 100 and 32 are 
>  >1e6.
>
> Do I have to file a new bug report?
>
> Sebastiaan
>