Fixed Point iteration using matlab, whats wrong with my code?

AI Thread Summary
The discussion revolves around troubleshooting a MATLAB code for fixed point iteration aimed at finding the root of an equation. The user is uncertain about the implementation of the while loop and how to correctly incorporate the modified function g(x). They provide a code snippet but encounter an error related to the convergence condition. There is a request for clarification on the specific error being faced and suggestions for commenting the code for better understanding. The conversation highlights the need for proper syntax and logical structure in the code to ensure successful execution of the fixed point iteration method.
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Fixed Point iteration using matlab, what's wrong with my code??

Homework Statement


We are suppose to use MatLab to make a program using the fixed point iteration to find the root of an equation.
I just can't figure out what I'm doing wrong here...

I'm pretty sure a while loop is the appropriate measure to use, but how should I go about plugging in g(x) which is the modified form of the original equation..

Homework Equations





The Attempt at a Solution



%finds the approximate root using fixed point iteration
%input: inline function g(x)
%guess point x0
%max error (err_max)
%number of iterations (n)
%output: x is the approx. root
%k is the number of iterations carried out

function root= fixed_point(g,x0,n,err_max)
i=1;
x(1)=g(x0);
while i<=n
x(i+1)=g(x(i));
if abs((x(i+1)-x(i))/(x(i+1)) < err_max
disp('Converges after k iterations')
k=i;
disp('The root to the equation is')
x(i+1)
return
end
i=i+1;
end
 
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What kind of error are you getting?
 


Could you comment your code? I can't quite figure out how this is supposed to perform fixed point iteration.
 
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