Constrain Normed instance to column vectors (m-by-1 matrices).

diff --git a/src/Linear/Matrix.hs b/src/Linear/Matrix.hs
index b17d0eb391484767cfed99d70f9b6ee7268a2394..8490b229921becb127a7a299be47efd16ddec7e4 100644 (file)
--- a/src/Linear/Matrix.hs
+++ b/src/Linear/Matrix.hs
@@ -417,9 +417,8 @@ instance (Ring.C a, Arity m, Arity n) => Module.C a (Mat m n a) where
 
 instance (Algebraic.C a,
           ToRational.C a,
-          Arity m,
-          Arity n)
-         => Normed (Mat (S m) (S n) a) where
+          Arity m)
+         => Normed (Mat (S m) N1 a) where
   -- | Generic p-norms. The usual norm in R^n is (norm_p 2). We treat
   --   all matrices as big vectors.
   --