diff --git a/app/Main.hs b/app/Main.hs
index 054050c..5644a65 100644
--- a/app/Main.hs
+++ b/app/Main.hs
@@ -18,8 +18,8 @@ precision = 5 :: Int
 showRatio :: Int -> Rational -> String
 showRatio p r = (if (r < 0) then "-" else "") ++ prepoint_digits ++ "." ++ postpoint_digits
     where
-    	prepoint_digits  = init . show . round $ (r * 10)
-	postpoint_digits = (take p) . (drop (length prepoint_digits)) . show . round $ (r * 10^p)
+    	prepoint_digits  = init . show . round . abs $ (r * 10)
+	postpoint_digits = (take p) . (drop (length prepoint_digits)) . show . round . abs $ (r * 10^p)
 
 useResult (Right e) = (showRatio precision) . evaluate $ replaceVars e vars
 useResult (Left  e) = show e
diff --git a/src/Lib.hs b/src/Lib.hs
index d83b50d..2b24d47 100644
--- a/src/Lib.hs
+++ b/src/Lib.hs
@@ -85,6 +85,7 @@ rationalPower :: Rational -> Rational -> Rational
 rationalPower a b = rationalPower' (numerator a, denominator a) (numerator b, denominator b)
     where
         rationalPower' (a, b) (c, 1) = a ^ c % b ^ c
+        rationalPower' _ _ = error "Powers with unnatural numbers are not supported yet"
 
 term = m_parens exprparser
        <|> fmap Variable m_identifier