MATLAB: Stopping the function from doing iteration (infinite while loop)

iterationmatlab functionwhile loop

After achieving the desired result the loop continues, how can i stop this? if truefunction y = mysqrt(x,y0,tol) % this function calculates the square root of a number x as y given the % less appropriate guess y0. The function ceases to iterate when the the % difference between y0 and y is less than 1e-3.

 y = (y0 + (x/y0))/2;
 y = (y + (x/y))/2;
 while abs(y-y0)>tol
     y = (y + (x/y))/2
 end

Best Answer

function y = mysqrt(x,y0,tol)
y = (y0 + (x/y0))/2;
y = (y + (x/y))/2;
while abs(y^2-x)>tol
   y = (y + (x/y))/2
end

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The underlying reason for this error message is that the output expected from the objective function provided to "fminsearch" is supposed to be a scalar as mentioned in the following link:

http://www.mathworks.com/help/matlab/ref/fminsearch.html

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Best Answer

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