Prolog implement and/2, or/2, nand/2, nor/2, xor/2

prolog implementation xor clpb nor
PROLOGik picture PROLOGik · Oct 28, 2013 · Viewed 9k times · Source

I want to implement the following predicates in prolog and use them for truth-tables: and/2, or/2, nand/2, nor/2, xor/2

Maybe someone can show me how to implement and/2 for example so I can do the others myself and post them here.

Answer

Cameron White picture Cameron White · Oct 31, 2013

/2 is possible and actually very elegent.

and(A,B) :- A,B.
or(A,B) :- A;B.
nand(A,B) :- not(and(A,B)).
nor(A,B) :- not(or(A,B)).
xor(A,B) :- or(A,B), nand(A,B).

To use just replace A/B with true/false. For example:

?- and(true,true).
true.
?- and(false, true).
false.

Related questions

'if' in prolog?

Is there a way to do an if in prolog, e.g. if a variable is 0, then to do some actions (write text to the terminal). An else isn't even needed, but I can't find any documentation of if.

Read More
Prolog "or" operator, query

I'm working on some prolog that I'm new to. I'm looking for an "or" operator registered(X, Y), Y=ct101, Y=ct102, Y=ct103. Here's my query. What I want to write is code that will: "return X, given that …

Read More
"Not equal" sign in Visual Prolog?

I can't find any documentation on "not equal" sign in Visual Prolog. Please provide the right solution of this problem: class predicates sister : (string Person, string Sister) nondeterm(o,o). clauses sister(Person, Sister) :- Person [not-equal-sign] Sister, parent(Person, …

Read More