DA question

[Randall Mackie]

Hi Amit,

Why do you need two staggered grids? I do EM finite difference frequency
domain modeling on a staggered grid using just one DA. Works perfectly fine.
There are some grid points that are not used, but you just set them to zero
and put a 1 on the diagonal of the coefficient matrix.


Randy


Amit.Itagi at seagate.com wrote:
> Hi Berend,
> 
> A detailed explanation of the finite difference scheme is given here :
> 
> http://en.wikipedia.org/wiki/Finite-difference_time-domain_method
> 
> 
> Thanks
> 
> Rgds,
> Amit
> 
> 
> 
>                                                                            
>              Berend van Wachem                                             
>              <berend at chalmers.                                             
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>              04/09/2008 02:59                                              
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> 
> 
> 
> Dear Amit,
> 
> Could you explain how the two grids are attached?
> I am using multiple DA's for multiple structured grids glued together.
> I've done the gluing with setting up various IS objects. From the
> multiple DA's, one global variable vector is formed. Is that what you
> are looking for?
> 
> Best regards,
> 
> Berend.
> 
> 
> Amit.Itagi at seagate.com wrote:
>> Hi,
>>
>> Is it possible to use DA to perform finite differences on two staggered
>> regular grids (as in the electromagnetic finite difference time domain
>> method) ? Surrounding nodes from one grid are used to update the value in
>> the dual grid. In addition, local manipulations need to be done on the
>> nodal values.
>>
>> Thanks
>>
>> Rgds,
>> Amit
>>
> 
> 
>