Another letrois explanation using cartesian coordinate system. N/M means neutrois or mesotrois/mesitrois/mestrois.
Ambitrois possibilities: ±, 0; 0, ±; +, -; -, +.
Positrois: +, +.
Negatrois: -, -.
Neutrois or mesotrois: 0, 0.
Nultrois or nulltrois: ∅ (out of the system)
Note that for cases of 0 & ± or ± & 0 they could be either ambitrois or positrois/negatrois (plus neutrois/mestrois).










