#include "petscdmnetwork.h" PetscErrorCode DMNetworkAssembleGraphStructures(DM dm)Collective
points = [0 1 2 3 4 5 6]
where edges = [0,1,2,3] and vertices = [4,5,6]. The new orderings will be specific to the subset (i.e vertices = [0,1,2] <- [4,5,6]).
With this new ordering a local PetscSection, global PetscSection and PetscSF will be created specific to the subset.