sig=shift(si,a)

% method of class @signal
% 
%   INPUT VALUES:
%  
%   RETURN VALUE:
%
% 
% (c) 2003, University of Cambridge, Medical Research Council 
% Stefan Bleeck ([e-mail])
% http://www.mrc-cbu.cam.ac.uk/cnbh/aimmanual
% $Date: 2003/01/17 16:57:43 $
% $Revision: 1.3 $

function sig=shift(si,a)
%usage: sig=shift(a)
% shifts all Values by the constant factor a

sig=si;
sig.werte(:)=sig.werte(:)+a;