Re: blog update #2

[c.]

On 14 Jun 2013, at 09:02, c. <address@hidden> wrote:

> Marco,
> 
> Thanks for your blog posts on meshing formats.
> I think your example on boundaries needs to be made more clear.
> 
> It is not usually sufficient to know whether a specific cell or node
> is on the boundary, one needs to know which part of the boundary it belongs 
> to.
> 
> For example in this BIM tutorial:
> http://wiki.octave.org/Bim_package#2D_Diffusion_Advection_Reaction_example
> 
> Boundary regions marked as 1 and 2 in the mesh structure are given a Dirichlet
> boundary condition while regions marked 3 and 4 are given a Neumann boundary 
> condition.
> 
> In dolfin how does one apply a different boundary condition to a different 
> region in the boundary?
> 
> could you add an example of this in your blog?
> 
> c.


The answer to this post on stack exchange:
http://scicomp.stackexchange.com/questions/7547/fenics-importing-mesh-along-with-material-and-boundary-data

seems to imply that one may save boundary/interior subdomains in dolfin xml 
files.

Indeed by browsing the python source for the xml_writer I see that the dolfin 
format supports a field named "domains"
which sounds as it could possibly do what you need.

If you can't find sufficient documentation about the file format go ahead and 
ask the developers!

c.