A = [10, -1 , 2, 0; -1, 11, -1 3; 2, -1, 10, -1; 0, 3,-1,8];
b = [1,1,1,1]'; n = 4; x = zeros(n,1);
x = Jacobi(A,b,.000001,40)
norm(A*x-b)

A = [10, -1 , 2, 0; -1, 11, -1 3; 2, -1, 10, -1; 0, 3,-1,8];
b = [1,1,1,1]'; n = 4; x = zeros(n,1);
x = Jacobi(A,b,0,10);
norm(A*x-b)
x = GS(A,b,0,10);
norm(A*x-b)