快速傅立葉變換是離散傅立葉變換的快速演算法，也可用於計算離散傅立葉變換的逆變換。快速傅立葉變換有廣泛的應用，如數位訊號處理、計算大整數乘法、求解偏微分方程等等。-Fast Fourier transform is a fast discrete Fourier transform algorithm can also be used to calculate the discrete Fourier transform of the inverse transform. Fast Fourier transform a wide range of applications, such as digital signal processing, computing large integer multiplication, solving partial differential equations, and so on.