fem.tet_radius_ratios

fem.tet_radius_ratios(points, cells)

Normalized radius ratio 3 r_in / r_circ per tet, in (0, 1].

The regular tetrahedron scores 1; slivers approach 0. Uses the exact inradius (3V / A_total) and circumradius (Cayley–Menger-free formula via opposite-edge products).