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Re: Mesh Refinement

 

I think I got it working. I used the version of eval which passes in
Data arguement.

On Sun, Jun 14, 2009 at 6:45 PM, Jehanzeb Hameed<jhameed2@xxxxxxxxxxxx> wrote:
> I want to do evaluate a form like this, arising from poisson equation
> with variable coefficient:
>
> k * dot(grad(v),grad(u))*dx
>
>
> To do this, I define k as
>
> cellElement = FiniteElement("Discontinuous Lagrange", "triangle", 0)
>
> k = Function(cellElement)
>
> Now I want to define values of k dependent on material type of cell.
> This is the link I cant figure out how to do.
>
> -Jehanzeb
>
> On Sun, Jun 14, 2009 at 5:50 PM, Jehanzeb Hameed<jhameed2@xxxxxxxxxxxx> wrote:
>> I am still struggling with this....
>>
>> I am trying to store subdomain identifiers in meshdata object, so that
>> they get updated when the mesh is refined. To do this, I have a file,
>> mesh.xml. In that file, there is a tag named "data". The "data" tag
>> has a child "array" with name = "material indicators". So, now when I
>> create mesh, will my meshdata have this array?
>>
>> And how do I create cell dependent functions. The example in Dolfin
>> user manual seems outdated. I think I need to use UFCfunction, but
>> what do I pass as Function arguement to its constructor (if
>> UFCfunction is indeed the correct way to go).
>>
>> -Jehanzeb
>>
>> On Thu, Jun 11, 2009 at 11:55 AM, Bartosz Sawicki<sawickib@xxxxxxxxxxxxx> wrote:
>>> Jehanzeb Hameed wrote:
>>>>
>>>> Hello,
>>>>
>>>> I am new to Dolfin, and was wondering how subdomains are supported as
>>>> regards to mesh reading and refinement. In my case, I will have a
>>>> mesh, with 2 subdomains. Each cell has an identifier indicating which
>>>> domain it belongs to. Looking at the examples, it seems I will need to
>>>> store domain identifiers in a separate xml file. Is that correct?
>>>
>>> Subdomain identifiers can be stored in different ways, as a separate
>>> MeshFunction, or in the MeshData structure.
>>> I prefer MeshData, because it is directly included in the Mesh object.
>>> You can also store boundary indicators using MeshData structure, see
>>> demo/pde/bcs.
>>>
>>>> With regard to mesh refinement, I assume I will be able to define
>>>> subdomains for each domain based on cell identifiers. Now, when I
>>>> refine the mesh, will the subdomains also be updated (i.e. will dolfin
>>>> know what domain the new cells belong to) ?
>>>
>>> If you name your MeshFunction "material indicators" it will be transformed
>>> to follow refined mesh. Arrays which store boundary indicators will be
>>> updated too.
>>> See LocalMeshRefinement::transformMeshData()
>>>
>>>> Also, is there a way to read archives of this list?
>>>
>>> Yes, there is http://www.fenics.org/pipermail/dolfin-dev/
>>>
>>> regrds.
>>> BArtek
>>>
>>>
>>>>
>>>> Thanks,
>>>> -Jehanzeb
>>>> _______________________________________________
>>>> DOLFIN-dev mailing list
>>>> DOLFIN-dev@xxxxxxxxxx
>>>> http://www.fenics.org/mailman/listinfo/dolfin-dev
>>>
>>>
>>
>


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