function dydt = vdpeq1(t,y)

% Evaluate the van der Pol ODEs for mu = 0.2

dydt = [y(2); 0.2*(1-y(1)^2)*y(2)-y(1)];

% "Complex and Chaotic Nonlinear Dynamics. 
% Advances in Economics and Finance, 
% Mathematics and Statistics" 
% T.Vialar, Springer 2009
% Copyright(c).