Fourier Transform, Fft, Fast Fourier Transform, Algorithms, Mathematics.
np.exp(-2j*np.pi*np.arange(n)/n) m = int(n/2) return np.concatenate([even_fft + twiddle_factors[:m]*odd_fft, even_fft + twiddle_factors[m:]*odd_fft]) f = abs(fft(x)) The time complexity of the above code is O(nlogn) instead of O(n²) in our naive DFT implementation above. This is because we are