[petsc-users] Plex Submesh

[Dharmendar Reddy]

On Tue, Apr 30, 2013 at 8:12 AM, Matthew Knepley <knepley at gmail.com> wrote:

> On Tue, Apr 30, 2013 at 2:57 AM, Dharmendar Reddy <dharmareddy84 at gmail.com
> > wrote:
>
>> Hello,
>>          I have a doubt about how the node ordering in plex submesh is
>> created.
>>
>> I create a oneD mesh along y-direction from a two dimensional square mesh
>> in x-y direction.  In the original mesh the nodes are indexed such that the
>> count increase in y-direction first and then in x-direction.
>>
>> Consider a 5 by 5 square mesh
>>
>> Now the oneD subdm  has 5 nodes and 4 cells
>>
>> if the coordinates of the nodes is [0,1.0,2.0,3.0,4.0]   in x and y
>> drection
>>
>> I see that  cells in the subdm for x=1.0 have support:
>> Vertex id here is the numbering with respect to subdm.
>>
>> cellId:     vertexId       ExpectedVertexId (or atleast i want this also
>> this will be the
>>                                                                    case
>> for x = 0.0)
>>
>>  0            5    4            4  5
>>  1            6    5            5  6
>>  2            7    6            6  7
>>  3            8    7            7   8
>>
>>  Of course this is consistent with the node ordering in original dm but i
>> i use the coordinates of the nodes i get detJacobain negative.
>>
>> I am not sure if this make sense ....
>>
>> Should not (or can ) the nodes in the subdm be reoriented such that they
>> all have positive orientation ?
>>
>
> I am working all of this out now, which is why I have been slow in
> replying. I have a code that uses
> this call in every possible way, in all dimensions. I should be done this
> week.
>
> You are correct that the orientation is likely off. That is what I am
> checking.
>

  Thanks...i am eagerly waiting for the updates...Hopefully I will graduate
soon... J

>
>   Thanks,
>
>      Matt
>
>
>> Since i am creating the subdm using indexset of a select points in
>> original dm, i can see that the connectivity is preserved.
>>
>> Should i create a new dm using DMcreatefromCellList after fixing the
>> orientations ? but then i need maps from this dm to orignal dm to access
>> the dof values.
>>
>> Thanks
>> Reddy
>> --
>> -----------------------------------------------------
>> Dharmendar Reddy Palle
>> Graduate Student
>> Microelectronics Research center,
>> University of Texas at Austin,
>> 10100 Burnet Road, Bldg. 160
>> MER 2.608F, TX 78758-4445
>> e-mail: dharmareddy84 at gmail.com
>> Phone: +1-512-350-9082
>> United States of America.
>> Homepage: https://webspace.utexas.edu/~dpr342
>>
>
>
>
> --
> What most experimenters take for granted before they begin their
> experiments is infinitely more interesting than any results to which their
> experiments lead.
> -- Norbert Wiener
>



-- 
-----------------------------------------------------
Dharmendar Reddy Palle
Graduate Student
Microelectronics Research center,
University of Texas at Austin,
10100 Burnet Road, Bldg. 160
MER 2.608F, TX 78758-4445
e-mail: dharmareddy84 at gmail.com
Phone: +1-512-350-9082
United States of America.
Homepage: https://webspace.utexas.edu/~dpr342
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20130430/45f5c01d/attachment.html>