cirshftt.m

用DSP译文版课本的程序,相信对学DSP的同学会有所帮助

function y = cirshftt(x,m,N)
% Circular shift of m samples wrt size N in sequence x: (time domain)
% -------------------------------------------------------------------
% [y] = cirshftt(x,m,N)
% y = output sequence containing the circular shift
% x = input sequence of length <= N
% m = sample shift
% N = size of circular buffer
%  Method: y(n) = x((n-m) mod N)

% Check for length of x
if length(x) > N
        error('N must be >= the length of x')
end
x = [x zeros(1,N-length(x))];
n = [0:1:N-1];
n = mod(n-m,N);
y = x(n+1);