[petsc-users] How/where to update DASetStencilWidth() info

[Xuefeng Li]

On Fri, 6 Jan 2012, Matthew Knepley wrote:

> On Fri, Jan 6, 2012 at 4:32 PM, Xuefeng Li <li at loyno.edu> wrote:
>
>> However, is there a way to change/adjust the stencil width
>> AFTER the DA has been created and set up to a DMMG? Or,
>> in general, can we attach different DA objects to a DMMG
>> at different times?
>>
>
> 1) You cannot change this after setting up the DA. Just make another DA,
> since
>    they are very lightweight.
>
> 2) I think structuring new code around DMMG is wrong. It has been removed in
>    petsc-dev and is deprecated in 3.2. What are you trying to do?
>
I am just trying to use the ghost points to share
data among neighboring processes at one step
during the whole iteration. At that particular
step, the stencil width needs to be bigger.

One can always set the stencil width to be big
enough so that one does not need to adjust it.
But this is just not as efficient as it can be.

Thanks again.

Regards,

--Xuefeng Li, (504)865-3340(phone)
   Like floating clouds, the heart rests easy
   Like flowing water, the spirit stays free
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