I would like to ask regarding the advantages and disadvantages of the regular Fast Fourier Transform (fft) and the non uniform version (nufft). I noticed that for nufft, we need to specify the time samples. However, what is the real advantage and disadvantage of fft and nufft? I read that nufft provides faster computation than fft. But then, why do we still use fft? Is it because choosing the time sample difficult? Looking forward hearing from you guys!