deff('yprime=f(t,y)','yprime=[y(2);y(3);2*y(3)+y(2)-2*y(1)]')
//
t=0:0.001:2;
Y=ode([1;3;-1],0,t,f);
plot2d(t,Y(1,:))
plot2d(t,-2/3*exp(2*t)+3*exp(t)-4/3*exp(-t),2)
