isto wrote:
] I've been trying to compile the following function
] (rounding to a desired degree):
]
] roundDec :: (Num a, Typeable a) => Int -> a -> a
] roundDec d a =
] let t = show (typeOf a)
] in case t of
] "Double" -> roundDDec d a
] "Complex Double" -> roundCDec d a
] otherwise -> a -- or something
]
] The two other functions are
]
] roundCDec :: (RealFloat a) => Int -> Complex a -> Complex a
] roundCDec d (c :+ b) = (roundDDec d c :+ roundDDec d b)
] and
] roundDDec :: (RealFloat a) => Int -> a -> a
] roundDDec d a = a -- or somegthing
Maybe you want type classes instead?
> import Complex
>
> class Round a where
> roundD :: Int -> a -> a
>
> instance Round Double where
> roundD d a = a
>
> instance (Round a, RealFloat a) => Round (Complex a) where
> roundD d (c :+ b) = (roundD d c :+ roundD d b)
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