let get_prev func status (states,trans) =
let st,tr = mk_empty_pre_or_post () in
let (_,trans_l) = Data_for_ltl.getAutomata() in
List.iter
(fun t ->
if (states.(t.stop.nums)) && (isCrossable t func status) && trans.(t.numt) then
st.(t.start.nums)<- true
)
trans_l;
List.iter
(fun t ->
if (st.(t.stop.nums)) then
tr.(t.numt)<- true
)
trans_l;
(st,tr)