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function [cl, or]=f_class(r) 
 
a = [r(length(r)) r r(1) r(2)]; 
b = (a(1:length(r)+1)-a(2:length(r)+2)); 
b = b./abs(b); 
d = ones(1,length(r)).*(b(1:length(r))>b(2:length(r)+1)); 
c = find(d); 
 
m = [(r(c))' c']; 
m = sortrows(m,1); 
 
or(1) = (m(1,2)-1)*pi/length(r)*2; 
cl = 2; 
 
dst = m(:,1)-m(1,1); 
i=find(dst < .3*(max(r)-min(r))); 
 
cl = length(i); 
or = (m(i,2)-1)*pi/length(r)*2;