%************************************************
%  MATLAB file for numerical solution from DE
%  AUTHOR: Balu Santhanam
%  DATE  : 03/19/01
%************************************************
function u_prime = de1(t,u)
    u_prime(1) = -u(1) -u(2) -u(3);
    u_prime(2) = u(1); 
    u_prime(3) = u(2); 
    u_prime = u_prime(:); 
return
