splitmix-0.1.1: Fast Splittable PRNG
Safe HaskellTrustworthy
LanguageHaskell2010

System.Random.SplitMix32

Description

SplitMix is a splittable pseudorandom number generator (PRNG) that is quite fast.

This is 32bit variant (original one is 32 bit).

You really don't want to use this one.

Synopsis

Documentation

data SMGen Source #

SplitMix generator state.

Instances

Instances details
Read SMGen Source #
>>> readMaybe "SMGen 1 1" :: Maybe SMGen
Just (SMGen 1 1)

>>> readMaybe "SMGen 1 2" :: Maybe SMGen
Nothing

>>> readMaybe (show (mkSMGen 42)) :: Maybe SMGen
Just (SMGen 142593372 1604540297)
Instance details

Defined in System.Random.SplitMix32

Methods

readsPrec :: Int -> ReadS SMGen #

readList :: ReadS [SMGen] #

readPrec :: ReadPrec SMGen #

readListPrec :: ReadPrec [SMGen] #

Show SMGen Source # 
Instance details

Defined in System.Random.SplitMix32

Methods

showsPrec :: Int -> SMGen -> ShowS #

show :: SMGen -> String #

showList :: [SMGen] -> ShowS #

NFData SMGen Source # 
Instance details

Defined in System.Random.SplitMix32

Methods

rnf :: SMGen -> () #

nextWord32 :: SMGen -> (Word32, SMGen) Source #

Generate a Word32.

>>> take 3 $ map (printf "%x") $ unfoldr (Just . nextWord32) (mkSMGen 1337) :: [String]
["e0cfe722","a6ced0f0","c3a6d889"]

nextWord64 :: SMGen -> (Word64, SMGen) Source #

Generate a Word64, by generating to Word32s.

nextTwoWord32 :: SMGen -> (Word32, Word32, SMGen) Source #

Generate two Word32.

nextInt :: SMGen -> (Int, SMGen) Source #

Generate an Int.

nextDouble :: SMGen -> (Double, SMGen) Source #

Generate a Double in [0, 1) range.

>>> take 8 $ map (printf "%0.3f") $ unfoldr (Just . nextDouble) (mkSMGen 1337) :: [String]
["0.878","0.764","0.063","0.845","0.262","0.490","0.176","0.544"]

nextFloat :: SMGen -> (Float, SMGen) Source #

Generate a Float in [0, 1) range.

>>> take 8 $ map (printf "%0.3f") $ unfoldr (Just . nextFloat) (mkSMGen 1337) :: [String]
["0.878","0.652","0.764","0.631","0.063","0.180","0.845","0.645"]

nextInteger :: Integer -> Integer -> SMGen -> (Integer, SMGen) Source #

Generate an Integer in closed [x, y] range.

splitSMGen :: SMGen -> (SMGen, SMGen) Source #

Split a generator into a two uncorrelated generators.

Generation

bitmaskWithRejection32 :: Word32 -> SMGen -> (Word32, SMGen) Source #

Bitmask with rejection method of generating subrange of Word32.

bitmaskWithRejection32 w32 generates random numbers in closed-open range of [0, w32).

bitmaskWithRejection32' :: Word32 -> SMGen -> (Word32, SMGen) Source #

Bitmask with rejection method of generating subrange of Word32.

bitmaskWithRejection32' w32 generates random numbers in closed-closed range of [0, w32].

Since: 0.0.4

bitmaskWithRejection64 :: Word64 -> SMGen -> (Word64, SMGen) Source #

Bitmask with rejection method of generating subrange of Word64.

bitmaskWithRejection64 w64 generates random numbers in closed-open range of [0, w64).

>>> take 20 $ unfoldr (Just . bitmaskWithRejection64 5) (mkSMGen 1337)
[0,2,4,2,1,4,2,4,2,2,3,0,3,2,2,2,3,1,2,2]

bitmaskWithRejection64' :: Word64 -> SMGen -> (Word64, SMGen) Source #

Bitmask with rejection method of generating subrange of Word64.

bitmaskWithRejection64' w64 generates random numbers in closed-closed range of [0, w64].

>>> take 20 $ unfoldr (Just . bitmaskWithRejection64' 5) (mkSMGen 1337)
[0,2,4,2,1,4,2,4,5,5,2,2,5,3,5,0,3,2,2,2]

Since: 0.0.4

Initialisation

mkSMGen :: Word32 -> SMGen Source #

Preferred way to deterministically construct SMGen.

>>> mkSMGen 42
SMGen 142593372 1604540297

initSMGen :: IO SMGen Source #

Initialize SMGen using entropy available on the system (time, ...)

newSMGen :: IO SMGen Source #

Derive a new generator instance from the global SMGen using splitSMGen.

seedSMGen Source #

Arguments

:: Word32

seed

-> Word32

gamma

-> SMGen 

Create SMGen using seed and gamma.

>>> seedSMGen 2 2
SMGen 2 3

seedSMGen' :: (Word32, Word32) -> SMGen Source #

Like seedSMGen but takes a pair.

unseedSMGen :: SMGen -> (Word32, Word32) Source #

Extract current state of SMGen.