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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] GivensQR
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Tue, 18 Aug 2009 17:30:54 -0400
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Thanks a lot!
> Pros:
>
> The computation of Q is performed only if strictly needed; by default (by
> the constructor) no computation is performed. Q is computed only if the user
> requests it.
that's something we'll have to uniformize across various
decompositions later on.
Actually I believe that the default should be "convenient but not
fast" i.e. compute Q, with an option to not compute Q. But we had yet
to discuss that on the list.
> The main algorithm (Givens rotations application) is written four times with
> small differences: one alteration in this algorithm requires actually four
> modification in the source.
Don't worry about that, we have new generic code for Jacobi rotations
which are just the same so i'll make your code use them.
OK, for the rest, i need to take a deeper look when i have time, but
thanks for your code, it's a good starting point and will same me lots
of time.
I'll polish and include it as soon as possible...
Benoit