Nonlinear algorithm for controlling dynamical systems, particularly where linear methods fail.
function ydot = lorenzeq(t,y)
%LORENZEQ Equation of the Lorenz chaotic attractor.
% ydot = lorenzeq(t,y).
% The differential equation is written in almost linear form.
% Copyright (c) 1984-94 by The MathWorks, Inc.
global SIGMA RHO BETA
A = [ -BETA 0 y(2)
0 -SIGMA SIGMA
-y(2) RHO -1 ];
ydot = A*y;