The 'Floating' class in the standard prelude reads:

class (Fractional a) => Floating a where pi :: a exp, log, sqrt :: a -> a (**), logBase :: a -> a -> a sin, cos, tan :: a -> a asin, acos, atan :: a -> a sinh, cosh, tanh :: a -> a asinh, acosh, atanh :: a -> a

-- Minimal complete definition: -- pi, exp, log, sin, cos, sinh, cosh -- asinh, acosh, atanh x ** y = exp (log x * y) logBase x y = log y / log x sqrt x = x ** 0.5 tan x = sin x / cos x tanh x = sinh x / cosh x

Please add asin, acos, and atan to the minimal complete definition list. [Incidentally, I find these minimal definition lists very useful; I'd love to see them become more than just comments.] --Dylan