MATLAB: FInd the function root

functionroot

How can I find the root of function without initial point?

I have a parametrized function, with one variable, N

a=@(N)(something)

How can I find the values of N without initial point , where a=0 ? … I've tried fzero but apparently it works only with initial value. Please help

Best Answer

You have to use a initial value (it can be 0). The fzero function uses a combination of bisection, secant, and inverse quadratic interpolation methods, but have to look around a point.

Actually, it doesn't really matter how precisse you are, but the problem could be that the function reaches it maximum number of iterations (which you can modify) before it get you the root value.

LINK

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