% Usage: A = A363(1000,100) % % Returns the matrix A defined by Trefethen problem 36.3. function A = A363(m,d2) if (nargin < 2) d2 = 0; end A = diag(sqrt([1:m])) + diag(ones(1,m-1),1) + diag(ones(1,m-1),-1); if (d2 > 0) A = A + diag(ones(1,m-d2),d2) + diag(ones(1,m-d2),-d2); end