[Haskell-cafe] Can't explain this error

[robert dockins]

You are trying to divide by an Integer and get a Float.  Haskell doesn't 
do automatic numeric conversion, so you have to do the casts manually.

Prelude> let sumHam n = sum [ 1 / (fromIntegral x) | x <- [1..n] ]
Prelude> sumHam 5
2.283333333333333


Dinh Tien Tuan Anh wrote:
> 
>  could anyone tell me what i did wrong with this please
> 
> sumHam :: Integer -> Float
> sumHam n = sum [1/x | x<-[1..n]]
> 
> Error: type error in explicitly typed binding
> **** Term:                 sumHam
> **** Type:                  Integer -> Integer
> **** Does not match : Integer -> Float
> 
> 
> 
> 
> it only works if i remove the first line. Tried changing Float by Double 
> and still not working
> 
> Pls help
> Cheers
> 
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