yade-dev team mailing list archive

[Luc Sibille <luc.sibille@xxxxxxxxxxxxxx>]

Hi,

> Below is an example (from revno 2514). If somebody see an obvious reason 
> > for getting a NaN, please let me know; if not, I'll send this to Eigen 
> > (the first line should be enough).
> >
> > Bruno
> >
> >
> > NaN angle found in angleAxisr(q), for quaternion 1 -1.56132e-11 
> > 7.47311e-11 -1.7066e-10,



I know nothing about quaternion, but based on Janek's comment:
> - you cannot have an angle if a2+b2+c2+d2 is different from one.

then the norm of the quaternion you suggest is slightly different from 1 
(of course not a lot, but a little...)


--
Luc Sibille

Université de Nantes - Laboratoire GeM UMR CNRS

IUT de Saint Nazaire
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44606 Saint-Nazaire Cedex, France

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