X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FPiecewise.hs;h=59af066db58dcd3a424f12576b76e7ae6998adad;hb=288455e9aade0b3a8abf138c4319beab3a0be705;hp=e550e4bf54659f434e88ea5ea369e5c61e3ada90;hpb=ba5fa4536b8171dd58afe38176da0b9c37032103;p=numerical-analysis.git

diff --git a/src/Piecewise.hs b/src/Piecewise.hs
index e550e4b..59af066 100644
--- a/src/Piecewise.hs
+++ b/src/Piecewise.hs
@@ -11,10 +11,9 @@ where
 import qualified Algebra.Additive as Additive ( C )
 import qualified Algebra.Field as Field ( C )
 import Control.Arrow ( first )
-import Data.Maybe ( catMaybes )
 import Misc ( partition )
 import NumericPrelude
-import qualified Prelude as P
+import Prelude ()
 
 -- | A predicate is basically a function that returns True or
 --   False. In this case, the predicate is used to determine which
@@ -42,8 +41,8 @@ data Piecewise a =
 --   point and the result is returned wrapped in a 'Just'. If the
 --   point is outside of the domain, 'Nothing' is returned.
 evaluate :: Piecewise a -> a -> Maybe a
-evaluate (Piecewise pieces) x =
-  foldl f Nothing pieces
+evaluate (Piecewise ps) x =
+  foldl f Nothing ps
   where
     f (Just y) _ = Just y
     f Nothing (p,g) = if p x then Just (g x) else Nothing