function n = orderselect(order,SIGMA)%ORDERSELECT   Select the model order.%%   Used in the functions BILINID and SUBID3B.   %% CUED System Identification Toolbox.% Cambridge University Engineering Department.% Copyright (C) 1998-2002. All Rights Reserved.% Version 1.00, Date: 01/06/2002% Created by H. Chen and E.C. Kerrigan. if isempty(order);   %  no order is given as input  n = min(rank(SIGMA),10);  disp(['Model order n = ',int2str(n),'.'])else  kk = length(order);  if kk > 1	order = sort(order(:));	eigvalue = zeros(1,kk);	for kkk=1:kk	  try		eigvalue(kkk) = SIGMA(order(kkk),order(kkk));	  catch		error('The block size is incompatible with this choice of order.')	  end	end         	eigvalue = log(eigvalue);	%plot(order,eigvalue,'k*')	bar(order,eigvalue)	axis([min(order)-1 max(order)+1 min(eigvalue)*.9 max(eigvalue)*1.1])	title('Model Order Selection')	xlabel('Model order')	ylabel('Log singular value')		n = input('Please select model order: ');	if isempty(n)	  n = min(rank(SIGMA),10);	  disp(['Model order n = ',int2str(n),'.'])	else	  if ~(n > 0 & fix(n) == n)		error('Model order must be a positive integer.')	  end	end	close(gcf)  else	n = order;  end end% *** last line of orderselect.m ***