Prolog If Then 规则

Question

考虑由以下规则定义的决策情况：

• 如果天气好，现在是夏天，那我就去海滩 • 如果天气好，而且是冬天，那我就去运河划船胜地 • 如果天气不好而且是夏天，那我就去上班 • 如果天气不好而且是冬天，那我去上课 • 如果我去海滩，我会游泳。 • 如果我去运河划船度假村，我会去划船 • 如果我去划船或游泳，那么我会很开心。 • 如果我去工作，我就会赚钱。 • 如果我去上课，那么我会学到一些东西。

遵循以下情况的规则（您对每种情况的结论是什么？）：

• 这是美好的一天，现在是夏天。 • 天气不好，现在是冬天。 • 这是美好的一天，现在是冬天。 • 这不是一个好日子，而且是夏天。

我无法为上述问题制定规则。请有人帮帮我。

Answer 1

您有一个 CNL（受控自然语言）规范：规则和情况以（非常）受限的英语子集表示。因此，作业的重点将放在处理语句的“真值”上……在 SWI-Prolog 中，我们可以这样写：

kb :- rules(Rs), maplist(writeln,Rs), situations(Ls), maplist(writeln,Ls).

rules(Rs) :- tokenize_atom('
    If it is a nice day and it is summer, then I go to the beach.
    If it is a nice day and it is winter, then I go to the canal boating resort.
    If it is not a nice day and it is summer, then I go to work.
    If it is not a nice day and it is winter, then I go to class.
    If I go to the beach, then I swim.
    If I go to the canal boating resort , then I go boat riding.
    If I go boat riding or I swim, then I have fun.
    If I go to work, then I make money.
    If I go to class, then I learn something. 
', L), maplist(downcase_atom,L,D), phrase(rule(Rs), D).

rule([r(C -> A)|Rs]) --> [if], condition(C), [,], [then], consequence(A), [.], rule(Rs).
rule([]) --> [].

situations(S) :- tokenize_atom('
    It is a nice day and it is summer.
    It is not a nice day and it is winter.
    It is a nice day and it is winter.
    It is not a nice day and it is summer.
',L), maplist(downcase_atom,L,D), phrase(situations(S), D).

situations([s(S)|Rs]) --> condition(S), [.], situations(Rs).
situations([]) --> [].

condition(and(A,B)) --> fact(A), [and], condition(B).
condition(or(A,B)) --> fact(A), [or], condition(B).
condition(C) --> fact(C).
consequence(C) --> fact(C).

fact(fact(true, What)) --> [it,is], what(What).
fact(fact(false, What)) --> [it,is,not], what(What).
fact(fact(true, Action)) --> [i], action(Action).

what([A,B,C]) --> [A,B,C].
what([A]) --> [A].

action(L) --> {between(1,6,N),length(L,N)},L.

我们得到

?- kb.
r((and(fact(true,[a,nice,day]),fact(true,[summer]))->fact(true,[go,to,the,beach])))
r((and(fact(true,[a,nice,day]),fact(true,[winter]))->fact(true,[go,to,the,canal,boating,resort])))
r((and(fact(false,[a,nice,day]),fact(true,[summer]))->fact(true,[go,to,work])))
r((and(fact(false,[a,nice,day]),fact(true,[winter]))->fact(true,[go,to,class])))
r((fact(true,[go,to,the,beach])->fact(true,[swim])))
r((fact(true,[go,to,the,canal,boating,resort])->fact(true,[go,boat,riding])))
r((or(fact(true,[go,boat,riding]),fact(true,[swim]))->fact(true,[have,fun])))
r((fact(true,[go,to,work])->fact(true,[make,money])))
r((fact(true,[go,to,class])->fact(true,[learn,something])))
s(and(fact(true,[a,nice,day]),fact(true,[summer])))
s(and(fact(false,[a,nice,day]),fact(true,[winter])))
s(and(fact(true,[a,nice,day]),fact(true,[winter])))
s(and(fact(false,[a,nice,day]),fact(true,[summer])))
true 
.

现在应该更简单地处理情况，推断动作......