嘿伙计们,我对Prolog有一个相当简单的问题。
%on(Block,Object).
% clear(Object).
block(b1).
block(b2).
block(b3).
place(p1).
place(p2).
place(p3).
place(p4).
state1([clear(p2),clear(p4),clear(b2),clear(b3),on(b1,p1),on(b2,p3),on(b3,b1)]).
% visual state1
% b3
% b1 b2
% = = = =
% 1 2 3 4 <----Positions
% can(Action,Condition).
% adds(Action,AddRelationship).
% deletes(Action,DeleteRelationship).
% move(Block,From,To).
can( move( Block, From, To), [ clear( Block), clear( To), on( Block, From)]) :-
block( Block), % Block to be moved
object( To), % "To" is a block or a place
To \== Block, % Block cannot bå moved to itself
object( From), % "From" is a block or a place
From \== To, % Move to new position
Block \== From. % Block not moved from itself
adds(move(X,From,To),[on(X,To),clear(From)]).
deletes(move(X,From,To),[on(X,From),clear(To)]).
object(X):-
place(X)
;
block(X).
% plan(State,Goals,Plan,FinalState).
plan(State,Goals,[],State):-
satisfied(State,Goals).
plan(State,Goals,Plan,FinalState) :-
append(PrePlan,[Action|PostPlan],Plan),
select(State,Goals,Goal),
achieves(Action,Goal),
can(Action,Condition),
plan(State,Condition,PrePlan,MidState1),
apply(MidState1,Action,MidState2),
plan(MidState2,Goals,PostPlan,FinalState).
% satisfied(State,[]).
satisfied(State,[Goal|Goals]):-
member(Goal,State),
satisfied(State,Goals).
select(State,Goals,Goal):-
member(Goal,Goals),
not(member(Goal,State)).
achieves(Action,Goal):-
adds(Action,Goals),
member(Goal,Goals).
apply(State,Action,NewState):-
deletes(Action,DelList),
delete_all(State,DelList,State1),!,
adds(action,AddList),
append(AddList,State1,NewState).
delete_all([],_,[]).
delete_all([X|L1],L2,Diff):-
member(X,L2),!,
delete_all(L1,L2,Diff).
delete_all([X|L1],L2,[X|Diff]):-
delete_all(L1,L2,Diff).
在编译器中运行后,它说它没有问题但是当我尝试执行命令时
plan(state1,on(b1,b2),Plan,FinalState).
它只是说出了全局堆栈。有人可以帮我修复这个
答案 0 :(得分:3)
你只需要看一下:
plan(State,Goals,[],State):- false,satisfied(State,Goals). plan(State,Goals,Plan,FinalState) :- append(PrePlan,[Action|PostPlan],Plan), false,select(State,Goals,Goal),achieves(Action,Goal),can(Action,Condition),plan(State,Condition,PrePlan,MidState1),apply(MidState1,Action,MidState2),plan(MidState2,Goals,PostPlan,FinalState). ?- plan(state1,on(b1,b2),Plan,FinalState).
由于此程序已经循环,因此相同的程序将循环删除其他 false
目标。您需要先解决此问题。有关详情,请参阅failure-slice。