function [ATw] = AT(w,n);

% calculate: Arrow(w)
% input: w ... vector: n*n + 1    
%       n ... dimension of matices A, B, C     
% 20. 12. 2000, rsotirov
% call: [ATw] = AT(w,n);

pom = 2: n*n+1;
Arrow = [w(1,1), - w(pom,1)'/2; - w(pom,1)/2, diag(w(pom,1))];		
ATw = Arrow;       

