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function [val,len] = rle(x) 
% RLE   Run Length Encoding 
%    [VAL,LEN] = RLE(X) encodes the data in vector X into run values, VAL, and 
%    run lengths, LEN. 
% 
%    Example: 
% 		>> X = [1 1 1 1 3 3 8 8 8 8 8 8] 
%       >> [VAL,LEN] = RLE(X) 
%    Returns: 
%       X = 
%            1     1     1     1     3     3     8     8     8     8     8     8 
%       VAL = 
%            1     3     8 
%       LEN = 
%            4     2     6 
% 
%    See also RLD. 
 
% Steve Hoelzer 
% 2003-09-04 
 
% Transpose input vector if necessary 
if (size(x,2)==1) 
    x = x.'; 
end 
 
% Error checking 
if (size(x,1)~=1) 
    error('RLE can only process vectors, not matrices') 
end 
 
% Encode 
i = [ find(x(1:end-1) ~= x(2:end)), length(x) ]; 
len = diff([ 0 i ]); % run lengths 
val = x(i);          % run values