更改 Prolog 中的输出 - 用于检测 covid 症状

Question

我想请问您能否建议我如何创建条件或重做代码。我需要程序的输出来检测 covid19 的症状。如果我在程序中的十个症状中至少有 3 次标记为“是”，则输出将是“您有 covid19 症状”。如果“是”少于 3 次，则输出将是“您没有 covid19 症状”。 谢谢

start :- x(Disease), write('the verdict is : '), write(Disease),nl, undo.


x(symptoms)   :- symptoms,!.
x(withoutsymptoms).  /* without symptoms */

symptoms :- verify(conjunctivitis),
            verify(sore_throat),            
            verify(fatigure),
            verify(shake),
            verify(diarrhea),        
            verify(runny_nose),      
            verify(cold),
            verify(muscle_pain),
            verify(chest_pressure),
            verify(loss_of_taste),          
            verify(fever).

ask(Question) :-
    write('How are you? '),
    write(Question),
    write('? '),
    read(Response),
    nl,
    ( (Response == yes ; Response == yes)
      ->
       assert(yes(Question)) ;
       assert(no(Question)), fail).

:- dynamic yes/1,no/1.

verify(S) :-
   (yes(S)
    ->
    true ;
    (no(S)
     ->
     fail ;
     ask(S))).

undo :- retract(yes(_)),fail.
undo :- retract(no(_)),fail.
undo.

Answer 1

这种尝试看起来令人困惑。下面的呢，它也不使用assertz/1 来戳Prolog 数据库，而是将响应收集在一个列表中以供以后分析。

此外，我们不使用“术语反序列化器”read/1，而是使用read_line_to_string/2

% ---
% Symptoms are listed naturally in a list.
% There are 11 symptoms

symptoms( [conjunctivitis,
           sore_throat,
           fatigue,
           shake,
           diarrhea,        
           runny_nose,      
           cold,
           muscle_pain,
           chest_pressure,
           loss_of_taste,          
           fever] ).

% ---
% Go through the symptoms list, collecting answers

ask_about_symptoms([],[]).
ask_about_symptoms([Symptom|MoreSymptoms],[Answer-Symptom|MorePairs]) :-
   repeat,
   format("Do you have: ~s?\n",[Symptom]),
   read_line_to_string(user_input,S1),
   string_lower(S1,S2),
   (
      member(S2,["yes","y","ja","oui"])
      ->
      Answer = yes
      ;
      member(S2,["no","n","nein","non"])
      ->
      Answer = no
      ;
      format("Please try again\n",[]),fail % Back to "repeat"
   ),   
   ask_about_symptoms(MoreSymptoms,MorePairs).
    
is_yes_pair(yes-_).

ask_candidate :-
   symptoms(Symptoms),
   ask_about_symptoms(Symptoms,AnswerPairs),
   !, % don't go back to asking
   include(is_yes_pair,AnswerPairs,Included),
   format("So you say you have the following symptoms: ~q~n",[Included]),
   length(Included,Hits),
   ((Hits>=3) -> format("Looks bad.~n",[]) ; format("You probably don't have it.~n",[])).

示例运行：

?- [rona].
true.

?- ask_candidate.
Do you have: conjunctivitis?
|: y
Do you have: sore_throat?
|: y
Do you have: fatigue?
|: n
Do you have: shake?
|: n
Do you have: diarrhea?
|: n
Do you have: runny_nose?
|: y
Do you have: cold?
|: foo
Please try again
Do you have: cold?
|: bar
Please try again
Do you have: cold?
|: n
Do you have: muscle_pain?
|: n
Do you have: chest_pressure?
|: y
Do you have: loss_of_taste?
|: y
Do you have: fever?
|: y
So you say you have the following symptoms: [yes-conjunctivitis,yes-sore_throat,yes-runny_nose,yes-chest_pressure,yes-loss_of_taste,yes-fever]
Looks bad.
true.