ufl team mailing list archive

["Garth N. Wells" <gnw20@xxxxxxxxx>]

On Apr 25 2009, Anders Logg wrote:

> On Sat, Apr 25, 2009 at 03:42:56PM +0100, Garth N. Wells wrote:
> > On Apr 25 2009, kent-and@xxxxxxxxx wrote:
> >
> > > > On Sat, Apr 25, 2009 at 03:10:07PM +0100, Garth N. Wells wrote:
> > > > > On Apr 25 2009, Anders Logg wrote:
> > > > >
> > > > > > On Sat, Apr 25, 2009 at 11:40:35AM +0200, Martin Sandve Alnæs wrote:
> > > > > > > I've verified the curl vs wikipedia and defined rot as the 
> > > > > > > z-component of the curl of the 2D vector operand embedded in 3D. Is 
> > > > > > > that right?
> > > > >
> > > > > rot is just a synonym for curl. For simplicity, I would remove rot.
> > > >
> > > > I'm used to the following notation (in pseudo-math):
> > > >
> > > >   rot:  R^2 --> R
> > > >   curl: R   --> R^2
> > > >   curl: R^3 --> R^3
> > >
> > > Agree.
> >
> > Must be a Scandinavian thing. All the references I'm finding on the net 
> > say that curl and rot are the same.
>
> Take a look at this, page 27:
>
>  http://www.ima.umn.edu/~arnold/papers/acta.pdf
>
> Ragnar Winther may be Norwegian, but not Doug Arnold and Richard Falk. :-)

Not the definitive reference, but certainly heavily scrutinised,

   http://en.wikipedia.org/wiki/Curl_(mathematics)

To quote: 

"The alternative terminology "rotor" and alternative notations 
\operatorname{rot}\ \mathbf{F} and \nabla\times\mathbf{F} are often used 
(the former especially in many European countries) for "curl" and 
\operatorname{curl}\ \mathbf{F}"

Garth

>