Dear sir:
I want to know if the MMG’s Tet cell has some specific node ordering?
Regards
What is the ordering of Tet nodes
Hello,
The nodes of tetrahedra cells are ordered in the forward direction. I copy a post with more informations about the Mmg numbering.
Tetra numbering in Mmg

edges are numbered in the order of their extremities indices:
 edge 0 is the edge with vertices 0  1
 edge 1 is the edge with vertices 0  2
 edge 2 is the edge with vertices 0  3
 edge 3 is the edge with vertices 1  2
 edge 4 is the edge with vertices 1  3
 edge 5 is the edge with vertices 2  3

A face is numbered with the index of its opposite vertex:
 face 0 is the face 1  2  3
 face 1 is the face 0  3  2
 face 2 is the face 0  1  3
 face 3 is the face 0  2  1
Illustration
numbering convention
Regards
Algiane