clear;
clf;

t = 0;
tstop = 2;
y0 = [1 2];

tspan = [t tstop];


[tt,yy] = ode23('func2',tspan,y0);


% plot numerical solution
plot(tt,yy(:,1), 'ro');
hold on;
plot(tt,yy(:,2), 'b*');
grid on;