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     Double, Float,
  12     module Data.Floating.Types.Core,
  13     module Data.Floating,
  14 ) where
  15
  16 import Prelude hiding (RealFloat(..), RealFrac(..), Double, Float)
  17 import Data.Floating.Types.Core hiding (Double, Float, FloatConvert)
  18 import Data.Floating.Instances
  19 import Data.Floating.Types.Double
  20 import Data.Floating.Types.Float
  21 import Data.Floating.Environment
  22 import Data.Floating.CMath.Instances
  23
  24 import Control.Monad
  25
  26 isInfinite :: PrimFloat a => a -> Bool
  27 isInfinite = (== FPInfinite) . classify
  28
  29 isNaN :: PrimFloat a => a -> Bool
  30 isNaN = (== FPNaN) . classify
  31
  32 isNormal :: PrimFloat a => a -> Bool
  33 isNormal = (== FPNormal) . classify
  34
  35 isSubNormal :: PrimFloat a => a -> Bool
  36 isSubNormal = (== FPSubNormal) . classify
  37
  38 isFinite :: PrimFloat a => a -> Bool
  39 isFinite = not . liftM2 (||) isInfinite isNaN
  40
  41 isNegativeZero :: PrimFloat a => a -> Bool
  42 isNegativeZero = liftM2 (&&) ((== FPZero) . classify) ((== (-1)) . signum)
  43
  44 -- | @fquotRem x y@ computes the remainder and integral quotient upon division
  45 -- of x by y.  The result is (x-n*y, n), where n is the value x/y rounded to
  46 -- the nearest integer.
  47 fquotRem :: RealFloat a => a -> a -> (a, a)
  48 fquotRem x y = (frem x y, nearbyint (x/y))