samer@4: function y=shiftl(x)
samer@4: % shiftl - shift a column vector up one
samer@4: % maintaining original length
samer@4: % eg [ 1 2 3 4 ] --> [ 2 3 4 0]
samer@4: if isvector(x)
samer@4: 	y = [ x(2:length(x)); 0];
samer@4: else
samer@4: 	y = [ x(:,2:size(x,2)), zeros(size(x,1),1) ];
samer@4: end