時系列データ型

gistfile1.hs

module Data (
    TimeSeries(..)
) where

data TimeSeries a = TimeSeries {
    delta :: a 
    , dataArray :: [a]
} deriving (Show)

computeDerivative :: (Floating a) => TimeSeries a -> TimeSeries a
computeDerivative s =
    let make' [] = []
        make' (d0:[]) = []
        make' (d0:d1:da) = ((d1 - d0)/(delta s)) : make' (d1:da)
    in TimeSeries (delta s) $ make' (dataArray s)