view aim-mat/tools/@signal/expand.m @ 0:74dedb26614d

Initial checkin of AIM-MAT version 1.5 (6.4.2011).

% method of class @signal
% function sig=expand(sig,newlength,[value])
%
% makes the signal longer (or shorter) by appending values with the value value
% if time is negative, then expand it to the front by filling the first time with value
%
%   INPUT VALUES:
%       sig: original @signal
%       newlength: the new length of the signal
%       value: value, with wich the new part is filled [0]
% 
%   RETURN VALUE:
%       time: time, when signal is bigger 0 for first time
%
% (c) 2003-2008, University of Cambridge, Medical Research Council 
% Maintained by Tom Walters ([e-mail]), written by Stefan Bleeck ([e-mail])
% http://www.pdn.cam.ac.uk/cnbh/aim2006
% $Date: 2008-06-10 18:00:16 +0100 (Tue, 10 Jun 2008) $
% $Revision: 585 $

function sig=expand(a,newlength,value)

lenalt=getlength(a);
sig=a; % erst mal eine Kopie des Signals
sr=getsr(a);
if newlength < 0 % aha, länger machen mit vorne auffüllen
    lenneu=lenalt-newlength;    % denn die newlength ist ja negativ
    temp=a.werte;

    start=time2bin(a,-newlength);
    stop=time2bin(a,lenneu);
    
    neuevals=ones(1,stop)*value;% erst alle mit den gewünschten Werten belegen
    bla=time2bin(a,lenalt);
    neuevals(start+1:stop)=temp(1:bla); % dann mit dem alten Signal überschreiben

    sig.werte(1:stop)=neuevals(1:stop);
    
else % positive neue Länge
    if lenalt>=newlength    %nothing to do
        return;
    end
    start=time2bin(a,lenalt);
    stop=time2bin(a,newlength);
    sig.werte(start:stop)=value;
end