Re: [Octave] Mesh

[Juan Pablo Carbajal]

On Sat, Jun 1, 2013 at 8:02 PM, Juan Pablo Carbajal
<address@hidden> wrote:
> On Sat, Jun 1, 2013 at 3:59 PM, Marco Vassallo
> <address@hidden> wrote:
>>
>>
>>> Subject: Re: [Octave] Mesh
>>> From: address@hidden
>>> Date: Sat, 1 Jun 2013 14:22:09 +0200
>>> To: address@hidden
>>
>>>
>>>
>>> On 31 May 2013, at 09:39, address@hidden wrote:
>>>
>>> > Message: 3
>>> > Date: Fri, 31 May 2013 00:52:31 +0200
>>> > From: Marco Vassallo <address@hidden>
>>> > To: "address@hidden" <address@hidden>
>>> > Subject: [Octave] Mesh
>>> > Message-ID: <address@hidden>
>>> > Content-Type: text/plain; charset="iso-8859-1"
>>> >
>>> > I would like to understand a little bit about mesh in Octave as
>>> > I have to use them with dolfin Mesh.
>>> > I have seen the forge pkg msh, but the documentation is not
>>> > very exhaustive.
>>>
>>> Marco the mesh format used by the msh package is extremely simple and is
>>> described
>>> here in detail for 2D:
>>>
>>> http://octave.sourceforge.net/msh/function/msh2m_structured_mesh.html
>>>
>>> and here for 3D
>>>
>>> http://octave.sourceforge.net/msh/function/msh3m_structured_mesh.html
>>>
>>> essentially it is just an Octave structure with 3 matrix fields:
>>>
>>> p is the list of vertices
>>> t is the connectivity matrix
>>> e is the list of boundary facets
>>>
>>> if you find that documentation unclear I'd be very glad to accept you
>>> patches to make more
>>> clear and to provide guidance in helping you prepare those patches.
>>>
>>>
>> this documentation is clear.
>> I was looking to the documentation for unstructured_mesh which refer to gmsh
>> manual
>> and so I was a little bit scared.
>> But I imagine that structured and unstructured mesh are managed with the
>> same format..
>>
>> Thanks,
>>
>> Marco
>>
>>
>>> > Is msh the only way in wich we can manage
>>> > mesh in Octave or there is some other options?
>>>
>>> yes msh is the only currently available mesh managing package I am aware
>>> of
>>> and it is part of Octave-Forge, not Octave.
>>>
>>> > Marco V.
>>>
>>> c.
>>>
>>>
>
> Hi Marco,
> Please also consider this type of conversion (again, without trying to
> overload you, just giving ideas)
> http://svn.code.sf.net/p/octave/code/trunk/octave-forge/main/geometry/inst/io/data2geo.m
>
> You can find all the quick&dirty Octave matrix to gmsh file format
> .geo in the private folder. It is basically string manipulation and I
> must say I am happy with the performance (I use this function
> intensively, I create meshes with the solution of an ODE, I know,
> weird, that's me!)
>
> I will be willing to give it a pump in a Octconf code-sprint if you
> think this will add up to your package.
>
> Cheers

A demo here
http://octave.sourceforge.net/geometry/function/data2geo.html