说明：  求一维序列x(n)的离散Fourier谱分析，s(0:m)离散功率谱，c(0:m)振幅谱，cta(0:m)位相谱，其中m=[n/2.]。
(The discrete Fourier spectral analysis of the request of one-dimensional sequence x (n), s (0: m) discrete power spectrum, c (0: m) amplitude spectrum, cta (0: m) phase spectrum, where m = [n/2. ].)