Re: [eigen] inconsistency in fast eigen decomposition |

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*To*: eigen@xxxxxxxxxxxxxxxxxxx
*Subject*: Re: [eigen] inconsistency in fast eigen decomposition
*From*: Gael Guennebaud <gael.guennebaud@xxxxxxxxx>
*Date*: Thu, 3 Feb 2011 14:21:01 +0100
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yes but was is strange in Radu's example is that the direct method
find a negative eigenvalue while they should all be positive (or equal
to zero). I guess that's because of the multiple trigonometric
functions. Anyway, now I start to compute the eigenvectors from the
biggest eigenvalue and compute the last eigenvectors from the first
two while taking care of some degenerated cases.
gael
On Thu, Feb 3, 2011 at 1:52 PM, Benoit Jacob <jacob.benoit.1@xxxxxxxxx> wrote:
> Yeah, it's hard to be accurate when there are degenerate eigenvalues.
> Radu's example had well separated eigenvalues.