Data/Floating.hs

   1 {-
   2  - Copyright (C) 2009-2010 Nick Bowler.
   3  -
   4  - License BSD2:  2-clause BSD license.  See LICENSE for full terms.
   5  - This is free software: you are free to change and redistribute it.
   6  - There is NO WARRANTY, to the extent permitted by law.
   7  -}
   8
   9 -- | Top level module for alternative floating point support.
  10 module Data.Floating (
  11     module Data.Floating.Classes,
  12     Double, Float,
  13     module Data.Floating,
  14     toFloating
  15 ) where
  16
  17 import Prelude hiding (RealFloat(..), RealFrac(..), Double, Float)
  18 import Data.Floating.Classes
  19 import Data.Floating.Instances
  20 import Data.Floating.Types
  21 import Data.Floating.Types.Double
  22 import Data.Floating.Types.Float
  23 import Data.Floating.Environment
  24 import Data.Floating.CMath.Instances
  25
  26 import Control.Monad
  27
  28 isInfinite :: PrimFloat a => a -> Bool
  29 isInfinite = (== FPInfinite) . classify
  30
  31 isNaN :: PrimFloat a => a -> Bool
  32 isNaN = (== FPNaN) . classify
  33
  34 isNormal :: PrimFloat a => a -> Bool
  35 isNormal = (== FPNormal) . classify
  36
  37 isSubNormal :: PrimFloat a => a -> Bool
  38 isSubNormal = (== FPSubNormal) . classify
  39
  40 isFinite :: PrimFloat a => a -> Bool
  41 isFinite = not . liftM2 (||) isInfinite isNaN
  42
  43 isNegativeZero :: PrimFloat a => a -> Bool
  44 isNegativeZero = liftM2 (&&) ((== FPZero) . classify) ((== (-1)) . signum)
  45
  46 -- | @fquotRem x y@ computes the remainder and integral quotient upon division
  47 -- of x by y.  The result is (x-n*y, n), where n is the value x/y rounded to
  48 -- the nearest integer.
  49 fquotRem :: RealFloat a => a -> a -> (a, a)
  50 fquotRem x y = (frem x y, nearbyint (x/y))