lorenzeqn.m

The programme ahout scientific computation

function ydot = lorenzeqn(t,y,A)
%  被交互实验 trylorenz 所调用
%  LORENZEQN  Equation of the Lorenz chaotic attractor.
%   ydot = lorenzeqn(t,y,A).
%   The differential equation is written in almost linear form.
%      ydot = A*y
%   where
%      A = [ -beta    0     y(2)
%               0  -sigma   sigma 
%            -y(2)   rho    -1  ];

A(1,3) = y(2);
A(3,1) = -y(2);
ydot = A*y;