+
+
+-- | x is very positive if it is 'epsilon' greater than zero.
+very_positive :: Double -> Bool
+very_positive x = x - epsilon > 0
+
+
+-- | Takes a list of Doubles and returns the ones which are not very
+-- positive.
+non_very_positive_entries :: [Double] -> [Double]
+non_very_positive_entries = filter (not . very_positive)