[petsc-users] Structured multi-block topology

[Mark Lohry]

Most common use case would be from 1 to 15 blocks or so, although I
have occasionally seen need for 100+. This also brings to mind a
question I had about more general connectivity in single-block domains
like a C-mesh, where you have halo dependencies to itself that are not
simply "periodic."



As far as the difficult task of setting up the communication, is that
even possible to do manually without treating everything as fully
unstructured? What other packages are out there for multi block
structured domains?

On Fri, Apr 25, 2014 at 2:40 PM, Barry Smith <bsmith at mcs.anl.gov> wrote:
>
>   Mark,
>
>    Are you thinking of the case of two or three (or so blocks) or are you thinking of many blocks?
>
>    DMComposite helps with multiple DM’s but unfortunately does not do the difficult task of setting up the communication of data between the different block boundaries.
>
>     There are some other packages out there for multi block domains that might be better for your case thus I ask about your particular situation and what you need.
>
>    Barry
>
> On Apr 25, 2014, at 1:31 PM, Mark Lohry <mlohry at gmail.com> wrote:
>
>> To resurrect this thread:
>> https://lists.mcs.anl.gov/mailman/htdig/petsc-users/2012-August/014930.html
>>
>> Matt Knepley suggested the correct way to handle a structred
>> multi-block mesh was to use DMComposite. I'm not seeing anything in
>> the documentation about how to properly use DMComposite, however.
>>
>> What are the necessary steps to go from a single-block code using DMDA
>> to a multi-block code that handles all the appropriate data passing at
>> block boundaries?
>