[petsc-users] DMDA Question

[Tim Gallagher]

Hi,

I'm trying to create some grids for a finite volume simulation and am a little stuck on the best way to tackle it. The approach now is to use DMDACreate3d with known number of I, J, K points and PETSC_DECIDE for the processors. Then I am trying to create another DMDA with the same distribution to store the cell centers and actual solution vector. The problem with is is the following:

Consider 9 points and two processors. Processor one gets points [1,5] with point 6 as a ghost and processor two gets points [6,9] with point 5 as a ghost. But now to create/store cell centers, processor two needs point 4 to construct a cell center for it's ghost. 

I can certainly fetch that point and do the calculation, but I feel like there is a more elegant way to do this out there. Has anybody used a DMDA to create a dual DMDA? 

Any advice would be appreciated,

Tim