Prolog "query"

Admin User, erstellt 25. Okt. 2024
         /**
          * Prolog code for the database query benchmark.
          *
          * This is the benchmark of page 226 of:
          * Warren, D.H.D. (1983): Applied Logic - Its Use and
          * Implementation as a Programming Tool,
          * Technical Note 290, SRI International, 1983
          *
          * We use integer  division instead of float division,
          * since float division is not yet available in Jekejeke
          * Prolog 0.8.4. Further complication by two temporary
          * variables T1 and T2.
          *
          * Warranty & Liability
          * To the extent permitted by applicable law and unless explicitly
          * otherwise agreed upon, XLOG Technologies AG makes no warranties
          * regarding the provided information. XLOG Technologies AG assumes
          * no liability that any problems might be solved with the information
          * provided by XLOG Technologies AG.
          *
          * Rights & License
          * All industrial property rights regarding the information - copyright
          * and patent rights in particular - are the sole property of XLOG
          * Technologies AG. If the company was not the originator of some
          * excerpts, XLOG Technologies AG has at least obtained the right to
          * reproduce, change and translate the information.
          *
          * Reproduction is restricted to the whole unaltered document. Reproduction
          * of the information is only allowed for non-commercial uses. Selling,
          * giving away or letting of the execution of the library is prohibited.
          * The library can be distributed as part of your applications and libraries
          * for execution provided this comment remains unchanged.
          *
          * Restrictions
          * Only to be distributed with programs that add significant and primary
          * functionality to the library. Not to be distributed with additional
          * software intended to replace any components of the library.
          *
          * Trademarks
          * Jekejeke is a registered trademark of XLOG Technologies AG.
          */
         
         % pop(-Atom, -Integer)
         pop(china,      8250).
         pop(india,      5863).
         pop(ussr,       2521).
         pop(usa,        2119).
         pop(indonesia,  1276).
         pop(japan,      1097).
         pop(brazil,     1042).
         pop(bangladesh,  750).
         pop(pakistan,    682).
         pop(w_germany,   620).
         pop(nigeria,     613).
         pop(mexico,      581).
         pop(uk,          559).
         pop(italy,       554).
         pop(france,      525).
         pop(philippines, 415).
         pop(thailand,    410).
         pop(turkey,      383).
         pop(egypt,       364).
         pop(spain,       352).
         pop(poland,      337).
         pop(s_korea,     335).
         pop(iran,        320).
         pop(ethiopia,    272).
         pop(argentina,   251).
         
         % area(-Atom, -Integer)
         area(china,     3380).
         area(india,     1139).
         area(ussr,      8708).
         area(usa,       3609).
         area(indonesia,  570).
         area(japan,      148).
         area(brazil,    3288).
         area(bangladesh,  55).
         area(pakistan,   311).
         area(w_germany,   96).
         area(nigeria,    373).
         area(mexico,     764).
         area(uk,          86).
         area(italy,      116).
         area(france,     213).
         area(philippines, 90).
         area(thailand,   200).
         area(turkey,     296).
         area(egypt,      386).
         area(spain,      190).
         area(poland,     121).
         area(s_korea,     37).
         area(iran,       628).
         area(ethiopia,   350).
         area(argentina, 1080).
         
         % density(-Atom, -Integer)
         density(C, D) :-
           pop(C, P),
           area(C, A),
           D is P*100 // A.
         
         % query
         query :-
           density(_, D1),
           density(_, D2),
           D1 > D2,
           T1 is 20 * D1,
           T2 is 21 * D2,
           T1 < T2.