How to use newton.m to find solutions to equations.

Hi. I've got a question that asks me to use the 'newton.m' function which I've downloaded and opened onto matlab, to solve 'x + 1 = atan(x)'. I am not sure how to use the newton.m program, and have not been able to find the method of using it online.

This is what I've got so far but i keep getting errors and am not sure where to go from here:

>> syms x

x_estimate = newton(x + 1 - atan(x), 1 - 1/(x^2 + 1), -1, 10^(-7))

Iteration xo x1 f(x)

========= =======================================================

Array indices must be positive integers or logical values.

Error in sym/subsref (line 890)

R_tilde = builtin('subsref',L_tilde,Idx);

Error in newton (line 14)

while ((abs(f(x0)) >= epsilon) && (Iter<30))

I'd really appreciate if anyone can help me with this.

Thanks a lot