fft_timereverse.m

用于模拟时变非平稳的ARMA过程

function Y= fft_timereverse(X)
% function Y= fft_timereverse(X)
%   This file is part of the TFPM toolbox v0.5 (c)
%   [e-mail] and underlies the GPL.
% 
% Comutes the time-reverse vector of the vector X. If X is a
% matrix, every column is reversed. 

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if(0)% TEST TEST TEST TEST TEST TEST TEST TEST TEST TEST
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X= [1 4;2 3;3 2;4 1];
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end;% TEST TEST TEST TEST TEST TEST TEST TEST TEST TEST
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Y= [X(1, :); flipud(X(2:end, :))];