From 9bf32e3aa583d44406e033669418a496cedb9181 Mon Sep 17 00:00:00 2001
From: Kyle Isom <kyle@imap.cc>
Date: Thu, 18 Jan 2018 18:01:08 -0800
Subject: [PATCH] Finish ch05 practical.

---
 lpn/ch05/practical.pl | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/lpn/ch05/practical.pl b/lpn/ch05/practical.pl
index b9b42f3..e99173e 100644
--- a/lpn/ch05/practical.pl
+++ b/lpn/ch05/practical.pl
@@ -34,10 +34,9 @@ min([H|T], N) :-
 %% should yield
 %%    Result  =  [6,21,12]
 scalarMult(_, [], []).
-scalarMult(K, [H|T], R) :-
-	V is K * H, 
-	scalarMult(K, T, [R|V]).
-	
+scalarMult(K, [H|T], [V|R]) :-
+	V is K * H,
+	scalarMult(K, T, R).
 
 %% 3. Another fundamental operation on vectors is the dot product. This
 %% operation combines two vectors of the same dimension and yields a
@@ -51,4 +50,9 @@ scalarMult(K, [H|T], R) :-
 %% the query
 %%    ?-  dot([2,5,6],[3,4,1],Result).
 %% should yield
-%%    Result  =  32
\ No newline at end of file
+%%    Result  =  32
+dot([], [], 0).
+dot([X|TX], [Y|TY], R) :-
+	dot(TX, TY, R2),
+	V is X * Y,
+	R is R2 + V.
\ No newline at end of file