| Re: [eigen] inconsistency in fast eigen decomposition |
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] inconsistency in fast eigen decomposition
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Thu, 3 Feb 2011 07:52:45 -0500
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2011/2/3 Gael Guennebaud <gael.guennebaud@xxxxxxxxx>:
> Hi,
>
> indeed, the code to extract the eigen vectors was quite naive. I've
> committed a more accurate version which should work fine for most use
> cases.
>
> I assume you are doing planar fit right? If so then the new version
> should really really be enough for you. It lacks some accuracy (but
> not too bad) only when all eigenvalues are relatively closed to each
> other. In this case there is no good planar approximation anyway.
Yeah, it's hard to be accurate when there are degenerate eigenvalues.
Radu's example had well separated eigenvalues.
Benoit