% matlab script to demonstrate Newton iteration in higher dimensions

% the system of nonlinear equations to be solved is defined in function f
% the Jacobian of f is defined in function Jf

xOld = input('Enter initial guess: ');

tol = input('Enter error tolerance: ');
error = 1;
count = 0;

while (error > tol),
   % this is what you want to do ...
   %   xNew = xOld - inv(Jf(xOld))*f(xOld)
   % this is how you do it ...
   xNew = xOld - Jf(xOld)\f(xOld)
   count = count + 1
   error = norm(xNew-xOld)+4*eps*norm(xNew)
   xOld = xNew;
   pause
end