| Re: [eigen] What about HyperPlane ? |
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] What about HyperPlane ?
- From: "Gael Guennebaud" <gael.guennebaud@xxxxxxxxx>
- Date: Thu, 28 Aug 2008 17:42:02 +0200
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On Thu, Aug 28, 2008 at 4:17 PM, Benoît Jacob <jacob@xxxxxxxxxxxxxxx> wrote:
> Why not; There is a question: do you think the hyperplane equation should have
> normalized normal vector?
definitely yes ! my class currently enforces unit normal.
> For most use cases, this is very useful. Like computing the distance from your
> hyperplane to points. It is much faster if the normal vector can be assumed
> to be normalized. For that reason a hyperplane class is much more useful with
> normalized normal vector.
exactly
> This will probably require to normalize in fitHyperplane() but that's no big
> deal, the cost is not much compared to the eigensolver used.
fitHyperplane() already returns a normalized normal because it is and
eigen vector. (hm... this remark might be quite confusing ! for the
lost reader: don't think Eigen's vectors cannot be non-unit, only
eigen ones are normalized ;) )
> Notify me before changing the fitHyperplane() API because this affects
> Avogadro :) We need to coordinate.
yes I know that, so I'll mark the old one with a deprecated gcc
warning for a few weeks....
gael.