|Re: [eigen] Transform.rotation() hang|
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] Transform.rotation() hang
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Wed, 11 Feb 2009 14:42:49 +0100
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2009/2/11 Keir Mierle <mierle@xxxxxxxxx>:
> I suspect a .truncate() function would be generally useful.
ok, it might be generally useful, but it's important to stress that
sane floating-point code should never require that; in fact, it should
never even care about the difference between a 1e-300 coefficient and
zero in a matrix whose norm is of the order of magnitude of 1.
So i think that a function like you suggest, would only ever be useful
when dealing with buggy code.
For sure, we want to shed all such buggy code from Eigen ASAP, the
only reason this SVD ever entered Eigen is that we needed a quick and
dirty first implementation but it was never meant to stay that way.
So if we add a function like that, it'll only be useful for dealing
with bad code presumably outside Eigen. So such a function can still
be worth having, but i wanted to mention that as it kind of
relativises the importance of such a function (again, except in the
very short term while we have bad SVD code).