====== Vectors inner product 2 ======
{{tag>math}}
===== Description =====
Computing inner products of vectors

**Source**:  The Art of Prolog
===== Download =====
Program source code: {{vectors_inner_product_2.pl}}
===== Listing =====
<code prolog>
/*
   inner_product(Xs,Ys,Value) :- 
	Value is the inner product of the vectors
	represented by the lists of integers Xs and Ys.
*/
     inner_product([X|Xs],[Y|Ys],IP) :-
	inner_product(Xs,Ys,IP1), IP is X*Y + IP1.
     inner_product([],[],0).

%  Program 8.7a   Computing inner products of vectors
</code>
===== Comments =====