# 3.3 FE 2
var("R,J")
plot_vector_field([J, -R+0.1*J], (R,-5,5), (J,-5,5), axes_labels=["R","J"])
t =srange(0,10,1)
sol=desolve_odeint([J,-R+0.1*J], ics=[1,1], dvars=[R,J], times=t)
list_plot(sol, color= "red", plotjoined=True, axes_labels=["R","J"])