| Re: [eigen] Another LDLt issue |
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] Another LDLt issue
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Mon, 30 Mar 2009 20:32:07 +0200
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>>Anyway,
>> routine dsytrf does an LDLt factorization for a symmetric but not
>> necessarily positive definite
>> matrix.
>
> Our LDLt does the same,
Oops, I misread what you wrote. So, dsytrf doesn't require the matrix
to be positive? interesting. I don't have an example of a symmetric
matrix that doesn't have an LDLt decomposition, I was just saying that
the standard algorithm couldn't handle all of them, but maybe dsytrf
uses another algorithm...
Benoit