Am Sonntag, 14. Mai 2006 09:30 schrieb SevenThunders: > I am new to Haskell and found myself in a bind concerning the use of > the C types, CDouble in particular. I extract a CDouble via it's pointer > from a StorableArray. Since the array must interface with C the elements > of the array must be CDouble. Now I'd like to use Text.Printf to format > print statements of elements of the array, but Text.Printf requires Doubles > as inputs and so far I have not found an obvious way to coerce CDoubles > into Doubles. [...]
You can use the Prelude function realToFrac to convert between the various floating-point types: ---------------------------------------------------------------- [EMAIL PROTECTED]:~> ghci -v0 Prelude> :t realToFrac realToFrac :: (Fractional t1, Real t) => t -> t1 Prelude> (realToFrac :: Foreign.C.Types.CDouble -> Double) 1234.5 1234.5 ---------------------------------------------------------------- As you can see from its type, realToFrac is not exactly about floating-point conversions, but for almost all practical use cases it is. :-) Cheers, S. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
