Reynolds number, FalsePosition getting multiple errors with no output

I am to create a function that uses FalsePosition (function shown below) to solve for f in the given equation. I think I'm missing some connections between my script and the function I'm trying to call.

Here is FalsePosition

This is my code:

function [root, fx, ea, iter] = falsepositionnew(y)
xl = 2500;
xu = 1000000;
es = 0.0000001;
maxit = 200;
Re = 10000:200000;
y = @(f, Re) 1/sqrt(f) - 4*log(Re*sqrt(f))+0.4;  %equation given 
for = i:numel(Re)
    f(i) = falseposition(y,xl,xu,es,maxit);
end