说明：  本文是快速折叠算法的算法描述，快速折叠算法用于检测隐含在数据中的周期性，在周期性检测上类似于FFT，常用在天文学中对脉冲星的探测。
(This article describes the fast folding algorithm is an algorithm, fast folding algorithm for detecting hidden periodicity in the data, periodic testing is similar to the FFT, commonly used to detect pulsars in astronomy.)