Main frequency Fast Fourier Transform (FFT)

I have an array X that contains a column with numbers from a time signal of 40hz sample. I want to find the main frequency component (MFC) of that array. I tried using ftt(X) function in matlab which returns a new complex array Y. What are the next step to find the MFC and the amplitude of MFC?

Answer 1

[Shadaab Siddiqie]

From my understanding you want to find frequency of signal in FFT. Here (link1 and link2) is a similar question which might help you.

[Michalis Gelastos]

To be honest, i'm not sure what i'm searching exactly. I have data from the accelerometer on the phone from x,y,z axis and i need to find the main frequency component. (It's a task from uni, that i have to do, so that's why i don't know what i'm looking for)