Re: DA question

[Randall Mackie <rlmackie862@xxxxxxxxx>]

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@xxxxxxxxxxx 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@chalmers.                                             
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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@xxxxxxxxxxx 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