what is the best data structure to represent prolog facts and rules bases in python

Question

i'm looking for the best data structure to represent prolog facts and rules bases in python for easy manipulation later , for example :

    parent(abraham,ismael).
    parent(abraham,isaac).
    parent(isaac,iacob).
    grandfather(B,N):- parent(B,P),parent(P,N).

is it the nested list like this :

base=[["parent","abraham","ismael"],["parent","abraham","isaac"],["parent","isaac","iacob"]]

or with dictionary :

base={"parent": ("abraham","ismael") ,"parent": ("abraham","isaac"), "parent":("isaac","iacob") }

or is there any best methods of representation that you suggest in this case .

PS: i mean by best : simplest , easiest , flexible way .

Sorry but this is off-topic as it's opinion-based as you're asking for best. Really you should just use what works until it doesn't work. Saying that this is similar to a network so you may consider networkx which supports these kinds of relationships — EdChum, Mar 23 '17 at 12:27
https://stackoverflow.com/questions/1917607/relational-logic-programming-in-python — languitar, Mar 23 '17 at 12:29
Define `'best'` (c: Algorithms and data structures go hand-in-hand. Do you mean the simplest, or most efficient, most flexible, extensible. What do you need to achieve with the data structure? Is it just defining the grandparent relationship? — Peter Wood, Mar 23 '17 at 12:31
@languitar i'm not looking for libraries , i have to implement it all by myself — Adelov, Mar 23 '17 at 12:31
@PeterWood i mean by best : simplest and easiest and flexible one ; and for the link that you gived to me : i'm not looking for libraries i have to implement it all by myself — Adelov, Mar 23 '17 at 12:34
See [PyKE](http://pyke.sourceforge.net/), in particular [this example](http://pyke.sourceforge.net/examples.html#family-relations) — Peter Wood, Mar 23 '17 at 12:38

score 1 · Answer 1 · edited May 31 '17 at 18:57

You can use python-like literal dict syntax directly in prolog.

Solution

{
    'parent':
    {
        'name_of_parent': 'abraham' ,
        'name_of_child': 'isaac'
    }
}
.

{
    'parent':
    {
        'name_of_parent': 'isaac'   ,
        'name_of_child': 'iacob'
    }
}
.

{
    'grandfather':
    {
        'name_of_grandfather':  __B__   ,
        'name_of_grandchild':   __N__
    }
}
:-
(
    {
        'parent':
        {
            'name_of_parent': __B__ ,
            'name_of_child': __P__
        }
    }
    ,
    {
        'parent':
        {
            'name_of_parent': __P__ ,
            'name_of_child': __N__
        }
    }
)
.

Example Query

?- 
{
    'grandfather':
    {
        'name_of_grandfather':  __B__ ,
        'name_of_grandchild':   __N__
    }
}
.
__B__ = abraham,
__N__ = iacob ;
false.

Caveat

The : operator might not be defined automatically for your implementation of prolog . If you get a syntax error because of the : , then place this at the top of your file:

:-  op((10'1),(yfx),(:))    .

you din't understand me i'm not looking to implement it in prolog i just want define facts and rules with the best data structure in python , so please re-read the post to get understand — Adelov, Mar 23 '17 at 15:33

what is the best data structure to represent prolog facts and rules bases in python

1 Answers1

Solution

Example Query

Caveat