[petsc-users] Updating ghost mapping for an existing vector?

[Kirk, Benjamin (JSC-EG311)]

>> I've got a contact problem with moving unstructured meshes.  The issue here
>> is that the required ghost indices can change during the course of a
>> simulation.  Is there a mechanism to reset the ghost indices for an existing
>> Vec object?
> 
> It can't be done at the system level without reallocation (assuming the number
> of ghost points has changed). This is a weakness of using ghost vectors
> compared to explicit local work vectors. How often do you want to do this?

Thanks for the reply.  Probably once per time step.  I'll work around it
then by writing an in-place vector replacement function that takes the new
ghost points and does the required copy...

-Ben