  function [A]  = gaussLU (A)
% function [A]  = gaussLU (A)
% LU factorization obtained from Gauss
% on return A stores the L and U factors
%--------------------------------------------
 n = size(A,1) ;
 for k=1:n-1 
   for i=k+1:n
     piv = A(i,k) / A(k,k) ;
     A(i,k) = piv;
     A(i,k+1:n)=A(i,k+1:n)-piv*A(k,k+1:n);
   end
 end 
