使用 mondial - 序言具有最长陆地边界的谓词

Question

我正在尝试使用的一些帮助来编写具有最长陆地边界的谓词。我在这里面临的问题是生成的输出不是我所期望的。

我的代码的当前输出按所有国家和大陆的 'circumference' 降序生成。但是我只需要每个大陆的一个条目（周长最大），其次，位于多个大陆的国家不能包含在输出中。

我的代码：

lb_country(Continent, Country):-
    setof(L-R-C, X^Y^Z^( encompasses(C, R, X),
                         \+ geo_sea(Y, C, Z),
                         circumference(L, C) ), Cs),
    reverse(Cs, HighToLowAreas),
    member(_-Continent-Country, HighToLowAreas).

包含谓词周长定义为


borders_sym(X,Y,L) :- borders(X,Y,L);borders(Y,X,L). 
bord(Country,L) :-     borders_sym(_,C,L),     Country = C.

circumference(C, Country) :-
    setof(P, bord(Country,P), List),sum_list(List,C).

example of encompasses and geo_sea

% encompasses(C,R,Fr), country C is encompassed by region R to fraction Fr (percent)
encompasses(austria,'Europe',100).
encompasses(austria,'Europe',100).
encompasses(afghanistan,'Asia',100).
encompasses(antigua_and_barbuda,'America',100).
encompasses(albania,'Europe',100).
encompasses(american_samoa,'Australia/Oceania',100).
encompasses(andorra,'Europe',100).
encompasses(angola,'Africa',100).
encompasses(armenia,'Asia',100).
encompasses(aruba,'America',100).
encompasses(australia,'Australia/Oceania',100).
encompasses(anguilla,'America',100).
encompasses(azerbaijan,'Asia',100).
encompasses(bangladesh,'Asia',100).
encompasses(barbados,'America',100).
encompasses(benin,'Africa',100).
encompasses(bermuda,'America',100).
encompasses(belgium,'Europe',100).
encompasses(burkina_faso,'Africa',100).
encompasses(pitcairn_islands,'Australia/Oceania',100).
encompasses(pakistan,'Asia',100).
encompasses(poland,'Europe',100).
encompasses(papua_new_guinea,'Australia/Oceania',100).
encompasses(puerto_rico,'America',100).
encompasses(paraguay,'America',100).
encompasses(qatar,'Asia',100).
encompasses(argentina,'America',100).
encompasses(russia,'Asia',75).
encompasses(botswana,'Africa',100).
encompasses(central_african_republic,'Africa',100).
encompasses(taiwan,'Asia',100).
encompasses(congo,'Africa',100).
encompasses(chile,'America',100).
encompasses(reunion,'Australia/Oceania',100).
encompasses(russia,'Europe',25).



% geo_sea(N,C,P), the sea N is in country C in province P
geo_sea('Andaman Sea',india,'Andaman and Nicobar Is.').
% geo_sea(N,C,P), the sea N is in country C in province P
geo_sea('Andaman Sea',india,'Andaman and Nicobar Is.').
geo_sea('Andaman Sea',myanmar,'Ayeyarwady').
geo_sea('Andaman Sea',myanmar,'Bago').
geo_sea('Andaman Sea',myanmar,'Mon').
geo_sea('Andaman Sea',myanmar,'Yangon').
geo_sea('Andaman Sea',indonesia,'Aceh').
geo_sea('Andaman Sea',thailand,'Thailand').
geo_sea('Arabian Sea',india,'Goa').
geo_sea('Arabian Sea',india,'Gujarat').
geo_sea('Arabian Sea',india,'Karnataka').
geo_sea('Arabian Sea',india,'Kerala').
geo_sea('Arabian Sea',india,'Lakshadweep Is.').
geo_sea('Arabian Sea',india,'Maharashtra').
geo_sea('Arabian Sea',oman,'Oman').
geo_sea('Arabian Sea',pakistan,'Balochistan').
geo_sea('Arabian Sea',pakistan,'Sindh').
geo_sea('Arctic Ocean',canada,'Northwest Territories').

borders predicate

% borders(X,Y,L), country X borders country Y, the border is L kilometers
borders(austria,switzerland,164).
borders(austria,czech_republic,362).
borders(austria,germany,784).
borders(afghanistan,china,76).
borders(afghanistan,iran,936).
borders(afghanistan,pakistan,2430).
borders(afghanistan,tajikistan,1206).
borders(afghanistan,turkmenistan,744).
borders(afghanistan,uzbekistan,137).
borders(austria,liechtenstein,37).
borders(austria,hungary,366).
borders(austria,italy,430).
borders(albania,greece,282).
borders(albania,kosovo,112).
borders(albania,macedonia,151).
borders(albania,montenegro,172).
borders(andorra,spain,65).
borders(andorra,france,60).
borders(angola,namibia,1376).

Answer 1

对于circumference/2，你可以这样写：

circumference(Country, C) :-
    findall(Km, ( border(Country, _, Km) ; border(_, Country, Km) ), Kms),
    sum_list(Kms, C).

table encompasses/3 有完整的国家名单吗？然后，您可以将“完全位于一个大陆上的国家”定义为：encompasses(Country, _, 100)?

要按大洲分组，并且只列出完全位于该大洲的国家，您可以这样做：

?- bagof(Country, encompasses(Country, Continent, 100), Countries).
Continent = 'Africa',
Countries = [angola, benin, burkina_faso] ;
Continent = 'America',
Countries = [antigua_and_barbuda, aruba, anguilla, barbados, bermuda] ;
Continent = 'Asia',
Countries = [afghanistan, armenia, azerbaijan, bangladesh] ;
Continent = 'Australia/Oceania',
Countries = [american_samoa, australia] ;
Continent = 'Europe',
Countries = [austria, albania, andorra, belgium].

你现在可以按照你的问题做：添加圆周，按它排序，反转，取第一个元素：

longest_border(Continent, Country, Length) :-
    bagof(N-C,
          (   encompasses(C, Continent, 100),
              circumference(C, N)
          ),
          Cs),
    keysort(Countries, S),
    reverse(S, [X-Y|_]).

但是你有很多数据丢失了。我得到：

?- longest_border(Continent, Country, Length).
Continent = 'Africa',
Country = angola,
Length = 1376 ;
Continent = 'America',
Country = bermuda,
Length = 0 ;
Continent = 'Asia',
Country = afghanistan,
Length = 5529 ;
Continent = 'Australia/Oceania',
Country = australia,
Length = 0 ;
Continent = 'Europe',
Country = austria,
Length = 2143.

使用 mondial - 序言具有最长陆地边界的谓词

Predicate with longest land border using mondial - prolog

predicate

prolog