1 files changed, 1 insertions, 1 deletions

diff --git a/packages/base/src/Data/Packed/Internal/Numeric.hs b/packages/base/src/Data/Packed/Internal/Numeric.hs
index 9adc023..257ad73 100644
--- a/packages/base/src/Data/Packed/Internal/Numeric.hs
+++ b/packages/base/src/Data/Packed/Internal/Numeric.hs
@@ -241,7 +241,7 @@ instance Container Vector (Complex Float)
 
 ---------------------------------------------------------------
 
-instance (Container Vector a) => Container Matrix a
+instance (Fractional a, Element a, Container Vector a) => Container Matrix a
   where
     size' = size
     scale' x = liftMatrix (scale' x)