> | restart; |
> | with(DEtools): |
> | kappa:=2: g:=1: |
> | de1 := diff(u(t),t) = u(t)*(1-u(t)/kappa)-u(t)*v(t); |
> | de2 := diff(v(t),t) = g*(u(t)-1) * v(t); |
> | dfieldplot([de1,de2], [u(t), v(t)], t=0..1, u=0..2, v=0..0.8); |
> | de3:=diff(u(t),t) = v(t)/sqrt(u(t)^2+v(t)^2); |
> | de4:=diff(v(t),t) = -u(t)/sqrt(u(t)^2+v(t)^2); |
> | dfieldplot([de3,de4], [u(t), v(t)], t=0..1, u=-1..1, v=-1..1); |
> | de5:=diff(u(t),t) = -u(t)/sqrt(u(t)^2+v(t)^2); |
> | de6:=diff(v(t),t) = v(t)/sqrt(u(t)^2+v(t)^2); |
> | dfieldplot([de5,de6], [u(t), v(t)], t=0..1, u=-1..1, v=-1..1); |
> |