implement your own newton-raphson iteration with a tolerance condition in matlab

To implement the Newton-Raphson iteration with a tolerance condition in MATLAB, you can follow these steps:

  1. Define your function, its derivative, and the initial guess:
main.m
f = @(x) x^3 - 2*x - 5;
df = @(x) 3*x^2 - 2;
x0 = 2;
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  1. Define a tolerance value:
main.m
tol = 1e-6;
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  1. Set a maximum number of iterations to prevent an infinite loop:
main.m
max_iter = 100;
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  1. Implement the iteration loop:
main.m
for iter = 1:max_iter
    % Evaluate the function and its derivative at the current x
    fx = f(x0);
    dfx = df(x0);
  
    % Compute the new x value using the Newton-Raphson formula
    x1 = x0 - fx/dfx;
  
    % Check if the tolerance condition is met
    if abs(x1 - x0) < tol
        break % exit the loop if the tolerance condition is met
    end
  
    % Update the value of x0 for the next iteration
    x0 = x1;
end
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  1. Output the result:
main.m
fprintf('The root is %f after %d iterations.\n', x1, iter);
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Note that you can replace the definition of f, df, and x0 with your own functions and initial guess. Also, the tol and max_iter values can be adjusted to suit your needs.

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