Each stratum can be characterized by the dimension of the entities ("points", to borrow the DMPLEX terminology), from 0- to 3-dimensional.
In some cases this numbering is used directly, for example with DMStagGetDOF(). To allow easier reading and to some extent more similar code between different-dimensional implementations of the same problem, we associate canonical names for each type of point, for each dimension of DMStag.
1-dimensional DMStag objects have vertices (0D) and elements (1D).
2-dimensional DMStag objects have vertices (0D), faces (1D), and elements (2D).
3-dimensional DMStag objects have vertices (0D), edges (1D), faces (2D), and elements (3D).
This naming is reflected when viewing a DMStag object with DMView() , and in forming convenient options prefixes when creating a decomposition with DMCreateFieldDecomposition().