spec.m

工程计算MATLAB code to calculate the reorthogonalized sine tapers input: N = the length of the time se

function [freq, a] = spec(X, N)
	
%%X = data of length N
%%gives frequencies and corresponding spectral estimate
%%(modulus squared of fft of the data); frequency from 
%%[0, 0.5]

freq=(0:(N-1))./(2*N);
freq=2*freq(1:(round(N/2)));
y=fft(X);
a=abs(y);
a=a.^2;
a=a(1:(round(N/2)));