Hello, I'm a student doing a project for my engeneering degree. I'm using DasyLab to analyze vibration on metal object. I have a signal, FFT of this signal and now im trying to calculate logarythmic decrement. My problem is, that on FFT data I want to find X values (in Hz) thats corresponds to calcucated Y value. For example if I my Y=0.1, I'd like to find all frequencies on X axis that coressponds to that Y value. Could anyone please help me where to look or give any tips? I will be forever thankful.