Why is the answer in my command window multiplying every time I press run??

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So I got the correct code..I think but when I press run the answer first showed up as x2 and when I pressed run the answer showed up x4 on command window.
My function:
function x=my_newton(f,Df,x0,tol)
%f=@(x)(x.^3-cos(4*x));
%Df=@(x)((3*x^2)+(4*sin(4*x)));
x=x0;kmax=10; tol=0.5e-8;
for k=1:kmax
d=-f(x)/Df(x);
x=x+d;
disp([x d])
if abs(d)<tol, break
end
end
msg=sprintf('warning');
if k==kmax, disp(msg);
end
And in a separate script I run:
f=@(x)(x.^3-cos(4*x));
x=linspace(-3,7);
plot(x,f(x))
axis([-3 7 -5 10]);grid on
hold on
%--------------
f=@(x)(x.^3-cos(4*x));
Df=@(x)((3*x^2)+(4*sin(4*x)));
x=my_newton(f,Df,[-0.9],1e-8);
x=my_newton(f,Df,[-0.4],1e-8);
x=my_newton(f,Df,[0.4],1e-8);
I get correct answer in Command window but first the answer showed up in x2 and then when I pressed again run and it just multiplies....What is wrong?
  6 Comments
Britney
Britney on 14 Oct 2014
sorry I saw just now that you commented on my question. I figured out what was wrong. It was the disp() in my while loop. I just put a % in front of it and my code worked out fine.
Thank you for taking the time.

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