% doc ode23 to get the explanation of this example

function odetest()
    options = odeset('RelTol',1e-4,'AbsTol',[1e-4 1e-4 1e-5]);
    [T,Y] = ode45(@rigid,[0 12],[0 1 1],options);
    plot(T,Y(:,1),'-',T,Y(:,2),'-.',T,Y(:,3),'.')
end
    
function dy = rigid(t,y)
    dy = zeros(3,1);    % a column vector
    dy(1) = y(2) * y(3);
    dy(2) = -y(1) * y(3);
    dy(3) = -0.51 * y(1) * y(2);
end