Working on the boundary problem for the vibrating string, so I want to apply simplex theory.
I figure the Euler number for the string v - e + f is calculated as 2.
The reason is the there are n + 1 nodes for n waves and the concatenation itself is the face. So we have n - (n + 1) + 1 = 2
This seems to apply to guitar, too. We have 6 strings which are the vertices, 5 intervals which are the edges, and one face which is the pitch value set.
Can anyone dispute the calculation?