[petsc-users] Unique number in each element of a DMPlex mesh

[Berend van Wachem]

Dear Petsc-Team,

Is there a good way to define a unique integer number in each element 
(e.g. a cell) of a DMPlex mesh, which is in the same location, 
regardless of the number of processors or the distribution of the mesh 
over the processors?

So, for instance, if I have a DMPlex box mesh, the top-right-front 
corner element (e.g. cell) will always have the same unique number, 
regardless of the number of processors the mesh is distributed over?

I want to be able to link the results I have achieved with a mesh from 
DMPlex on a certain number of cores to the same mesh from a DMPlex on a 
different number of cores.

Of course, I could make a tree based on the distance of each element to 
a certain point (based on the X,Y,Z co-ordinates of the element), and go 
through this tree in the same way and define an integer based on this, 
but that seems rather cumbersome.

Thanks and best regards, Berend.