An array of frequencies and an array of impedance/amplitude values. Find the assymptote so that i can calculate cutoff frequency

Hello,

My aim is to find the cutoff frequency and wout, of the input data, array of frequencies and array of the impedance values. I want to plot de bode diagram. I tried with bode() but it only fits for transfer functions. I even tried with the code presented in (https://de.mathworks.com/matlabcentral/answers/314007-bode-plot-and-cutoff-frequency ) but it gives me the wrong wout and cutoff frequency. I think the problem using my data is of having no maximum gain or maximum value of impedance.

I could take the maximum value but I don't think it is correct, only in last case. So I am trying to find the horizontal asymptote of the graphic so that I can calculate manually the cutoff frequency.

Thank you in advance