 Fast Fourier transform

An efficient algorithm to calculate the discrete Fourier transform.

The Fast Fourier Transform (FFT) is an algorithm that computes the Discrete Fourier Transform (DFT) and its inverse efficiently. The DFT is a mathematical transformation used to analyze the frequency content of discrete signals, transforming a sequence of complex numbers into another sequence of complex numbers. The basic idea is to express a discrete signal as a sum of sinusoids, which can provide insights into the signal's frequency characteristics.