Dear all,

I'm created a timeSignal datatype as container around a "Vector Double" data
type (see simple code below) and subsequently started to instanciate Num &
Eq to be able to perform operations on it. Additionally I want store ifno
like an index, time information and eventually an inheritence log (the log
is not yet in there).

As I will in the end need up to 10 different datatypes, however using
slightly different content (time signal, single value, distribution, ...) I
ask myself, how I could define a super data-type with sub-data-types to
inherit, but then also overload certain functions (like u would do in OO).

What is best way in haskell to achieve this ? (I'm unsure wether haskell
classes are what I'm looking for)

Cheers Phil

########## Code below

import qualified Data.Vector.Unboxed as V

data TimeSig = TimeSig Int Double (V.Vector Double) -- signal Index timeStep
data

getVect :: TimeSig -> (V.Vector Double)
getVect (TimeSig idx dt vect)= vect

getIdx :: TimeSig -> Int
getIdx (TimeSig idx dt vect) = idx

getdt :: TimeSig -> Double
getdt (TimeSig idx dt vect) = dt

pzipWith :: (Double -> Double -> Double) -> TimeSig -> TimeSig -> TimeSig
pzipWith f p1 p2 =  TimeSig idx dt vect
             where
               vect = V.zipWith f (getVect p1)  (getVect p2)
               idx = getIdx p1
               dt = getdt p1

pmap :: (Double -> Double) -> TimeSig -> TimeSig
pmap f p = TimeSig (getIdx p) (getdt p) (V.map f (getVect p))

instance Num TimeSig
     where
     (+) p1 p2 = pzipWith (+) p1 p2
     (-) p1 p2 = pzipWith (-) p1 p2
     negate p1 = pmap negate p1
     abs p1 = pmap abs p1
     (*) p1 p2 = pzipWith (*) p1 p2

instance Eq TimeSig where
           (==) p1 p2 = (==) (getVect p1) (getVect p2)


instance Show TimeSig where
 show (TimeSig idx dt vect) = "TimeSignal Nr: " ++ show idx ++ "  dt: " ++
show dt ++ " val:" ++ show vect



main = do

       let p = TimeSig 5 0.1 (V.fromList [0..10::Double])
       putStrLn (show p)
       putStrLn (show (p+p))

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