Type 0	Node i is a vertex of all terminal cells, ib ∈ {Ni}, which implies that it is not a hanging node. Type 0 nodes are further distinguished into two sub-types:
	Type 0A	All ib ∈ {Ni} are of equal size.
	Type 0B	The members ib ∈ {Ni} differ in size.
Type 1	The node lies on the mid-edge of at least one terminal cell, ib ∈ {Ni}.
Type 2	The node lies on the center of a terminal cell face of exactly one terminal cell, ib∈ {Ni}.