MATLAB: NxN matrix with 2s on main diagonal

matrix

How do I create NxN matrix which has 2s on main diagonal, -1s on diagonal above and below 2s and -1 last element (Nth) in the first row and first element in Nth row.

Best Answer

N = 8; %e.g.
m = full(gallery('tridiag', N));
m([N, (N-1)*N+1]) = -1