Fourier series of time domain data
Before doing the FFT, you will need to resample or interpolate the data until you get a set of amplitude values equally spaced in time.
I spent couple days trying to solve this problem, but no luck so I turn to you. I have file for a photometry of a star with time and amplitude data. I'm supposed to use this data to find period changes. I used Lomb-Scargle from pysca library, but I have to use Fourier analysis. I tried fft (dft) from scipy and numpy but I couldn't get anything that would resemble frequency spectrum or Fourier coefficients. I even tried to use nfft from pynfft library because my data are not evenly sampled, but I did not get anywhere with this. So if any of you know how to get from Fourier analysis main frequency in periodical data, please let me know.