From: Michael Orlitzky <michael@orlitzky.com>
Date: Wed, 17 Oct 2012 16:40:38 +0000 (-0400)
Subject: Require Vector instances to be instances of Num as well.
X-Git-Url: https://gitweb.michael.orlitzky.com/?a=commitdiff_plain;h=d3b5d9259dd9f0650d51447d7f57ed6d782dfdeb;p=numerical-analysis.git

Require Vector instances to be instances of Num as well.
---

diff --git a/src/Vector.hs b/src/Vector.hs
index e608a50..97bb5d8 100644
--- a/src/Vector.hs
+++ b/src/Vector.hs
@@ -7,7 +7,7 @@ where
 
 import Data.Number.BigFloat
 
-class Vector a where
+class (Num a) => Vector a where
   norm :: RealFrac b => a -> b
 
 -- Define instances for common numeric types.