-- | Data.Index is a package for adding index column to data files module Data.Index ( hello , addTime) where -- | say hello hello :: String hello = "Hello Data.Index!" -- | Add an time column -- usage: addTime <data array> <time unit> addTime :: Num a => [[a]] -> a -> [[a]] addTime array time_unit = aux array time_unit [] where aux :: Num a => [[a]] -> a -> [[a]] -> [[a]] aux [] _ accum = reverse accum aux (x:xs) unit accum = aux xs unit ((i:x):accum) where i = unit * (fromIntegral ((length accum) + 1))