ffc team mailing list archive

[Shawn Walker <walker@xxxxxxxxxxxxxxx>]

Actually, I meant how do I use the normal vector of the boundary in an 
FFC.form file?

for example, I would like to have this (in my .form file):

n = FacetNormal("triangle")
a = dot(v, u)*dx + dot(grad(v), grad(u))*dx + dot(v, n)*dot(u, n)*ds

It compiles fine in FFC, and the dolfin code also compiles.  But when I 
run it, it crashes and says that some coefficient is not set.  It seems to 
not know what `n' is.

- Shawn

On Mon, 13 Apr 2009, Harish Narayanan wrote:

> Shawn Walker wrote:
> > I was just wondering if the FacetNormal will be coming back to FFC any
> > time soon?
>
> I'm not sure it's gone anywhere (unless something changed really
> recently). The earlier syntax, FacetNormal(shape, mesh), is now
> FacetNormal(mesh).
>
> Harish