> This returns me a list of [t,x,y]. How can I plot x(t) and y(t)?
Separate your values into pairs [t,x] and [t,y] and use the discrete
option of plot2d:
xtvalues: map(lambda([e], part(e,[1,2])), res);
ytvalues: map(lambda([e], part(e,[1,3])), res);
plot2d([
[discrete, xtvalues],
[discrete, ytvalues]
]);