I am running the python program which is exectuing prolog queries(using pyswip library) the problem in this is that i am not getting the value of the variable in the output instead i am getting type of it like Atom/Variable with some address.
here is the code,
from pyswip import Prolog
swipl = Prolog()
swipl.retractall('car(_)')
swipl.assertz('(fun(X) :- car(X),red(X))')
#swipl.assertz('car(porcshe)')
swipl.assertz('car(Mercedez)')
swipl.assertz('car(Buggati)')
swipl.assertz('car(Audi)')
print (list(swipl.query('car(Which)')))
Output:-
[{'Which': Variable(100)}, {'Which': Variable(100)}, {'Which': Variable(70)}]
Why it is giving output like this?
Remember that Prolog variables start with an upper case letter and constants start with a lower case letter.
So your program:
car(Mercedes).
car(Bugatti).
car(Audi).
Allows for any substitution:
?- car(beethoven).
true ; % Mercedes = beethoven
true ; % Bugatti = beethoven
true. % Audi = beethoven
A shorter version of your program would be:
car(_Anything).
But you probably don't want that anything is a car. Try replacing the variables by constants (mercedes, bugatti, audi).
Regarding Variable(100): when you use the underscore as a don't care notation for the contents of a variable or Prolog has to introduce variables for other reasons, they usually just get a number. I assume to distinguish the variable #100 from the nuber 100, they write Variable(100)- you can recognize it's not a Prolog term because Variable would be a variable but variables don't have arguments. So if you parse the output it would be clear what is meant.