On Wed, Mar 12, 2008 at 9:27 PM, Don Stewart <[EMAIL PROTECTED]> wrote:
> You could consider binding directly to the C functions, if needed,
>
> {-# OPTIONS -fffi -#include "math.h" #-}
>
> import Foreign.C.Types
>
> foreign import ccall unsafe "math.h log10"
> c_log10 :: CDouble -> CDouble
>
> log10 :: Double -> Double
> log10 x = realToFrac (c_log10 (realToFrac x))
Actually, you could almost certainly just use
foreign import ccall unsafe "math.h log10" log10 :: Double -> Double
since in ghc CDouble and Double are identical.
It's a bit sloppier, but shouldn't cause any trouble. And I've no
idea how realToFrac is implemented, but would worry about it behaving
oddly... for instance when given NaNs.
David
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