Find sphere points in a lattice
Hello, say I have a lattice as in
Q = RootSystem('E8').weight_lattice()
with it's canonical bilinear form. How do I find the vectors v such that (v,v)=n for a positive integer n?
Edit: it would be even better if there's a way to get the points inside a cone, say the principal chamber in the above example.
Could you explain what is meant by "canonical bilinear form", the one coming from the geometric representation?
This will affect how to give you a better answer.
The one coming from the Killing for on the Cartan algebra.