module RangeTest (main) where
import Control.Monad
import System.Random
import Data.Int
import Data.Word
import Foreign.C.Types
-- Take many measurements and record the max/min/average random values.
approxBounds ::
(RandomGen g, Random a, Ord a, Num a) =>
(g -> (a,g)) -> Int -> a -> (a,a) -> g -> ((a,a,a),g)
-- Here we do a little hack to essentiall pass in the type in the last argument:
approxBounds nxt iters unused (explo,exphi) initrng =
if False
then ((unused,unused,unused),undefined)
-- else loop initrng iters 100 (-100) 0 -- Oops, can't use minBound/maxBound here.
else loop initrng iters exphi explo 0
where
loop rng 0 mn mx sum' = ((mn,mx,sum'),rng)
loop rng n mn mx sum' =
case nxt rng of
(x, rng') -> loop rng' (n-1) (min x mn) (max x mx) (x+sum')
-- We check that:
-- (1) all generated numbers are in bounds
-- (2) we get "close" to the bounds
-- The with (2) is that we do enough trials to ensure that we can at
-- least hit the 90% mark.
checkBounds ::
(Real a, Show a, Ord a) =>
String -> (Bool, a, a) -> ((a,a) -> StdGen -> ((a, a, t), StdGen)) -> IO ()
checkBounds msg (exclusive,lo,hi) fun = do
-- (lo,hi) is [inclusive,exclusive)
putStr $ msg ++ ": "
(mn,mx,_) <- getStdRandom (fun (lo,hi))
when (mn < lo) $ error $ "broke lower bound: " ++ show mn
when (mx > hi) $ error $ "broke upper bound: " ++ show mx
when (exclusive && mx >= hi)$ error$ "hit upper bound: " ++ show mx
let epsilon = 0.1 * (toRational hi - toRational lo)
when (toRational (hi - mx) > epsilon) $ error $ "didn't get close enough to upper bound: "++ show mx
when (toRational (mn - lo) > epsilon) $ error $ "didn't get close enough to lower bound: "++ show mn
putStrLn "Passed"
boundedRange :: (Num a, Bounded a) => (Bool, a, a)
boundedRange = ( False, minBound, maxBound )
trials :: Int
trials = 5000
-- Keep in mind here that on some architectures (e.g. ARM) CChar, CWchar, and CSigAtomic
-- are unsigned
main :: IO ()
main =
do
checkBounds "Int" boundedRange (approxBounds random trials (undefined::Int))
checkBounds "Integer" (False, fromIntegral (minBound::Int), fromIntegral (maxBound::Int))
(approxBounds random trials (undefined::Integer))
checkBounds "Int8" boundedRange (approxBounds random trials (undefined::Int8))
checkBounds "Int16" boundedRange (approxBounds random trials (undefined::Int16))
checkBounds "Int32" boundedRange (approxBounds random trials (undefined::Int32))
checkBounds "Int64" boundedRange (approxBounds random trials (undefined::Int64))
checkBounds "Word" boundedRange (approxBounds random trials (undefined::Word))
checkBounds "Word8" boundedRange (approxBounds random trials (undefined::Word8))
checkBounds "Word16" boundedRange (approxBounds random trials (undefined::Word16))
checkBounds "Word32" boundedRange (approxBounds random trials (undefined::Word32))
checkBounds "Word64" boundedRange (approxBounds random trials (undefined::Word64))
checkBounds "Double" (False,0.0,1.0) (approxBounds random trials (undefined::Double))
checkBounds "Float" (False,0.0,1.0) (approxBounds random trials (undefined::Float))
checkBounds "CChar" boundedRange (approxBounds random trials (undefined:: CChar))
checkBounds "CSChar" boundedRange (approxBounds random trials (undefined:: CSChar))
checkBounds "CUChar" boundedRange (approxBounds random trials (undefined:: CUChar))
checkBounds "CShort" boundedRange (approxBounds random trials (undefined:: CShort))
checkBounds "CUShort" boundedRange (approxBounds random trials (undefined:: CUShort))
checkBounds "CInt" boundedRange (approxBounds random trials (undefined:: CInt))
checkBounds "CUInt" boundedRange (approxBounds random trials (undefined:: CUInt))
checkBounds "CLong" boundedRange (approxBounds random trials (undefined:: CLong))
checkBounds "CULong" boundedRange (approxBounds random trials (undefined:: CULong))
checkBounds "CPtrdiff" boundedRange (approxBounds random trials (undefined:: CPtrdiff))
checkBounds "CSize" boundedRange (approxBounds random trials (undefined:: CSize))
checkBounds "CWchar" boundedRange (approxBounds random trials (undefined:: CWchar))
checkBounds "CSigAtomic" boundedRange (approxBounds random trials (undefined:: CSigAtomic))
checkBounds "CLLong" boundedRange (approxBounds random trials (undefined:: CLLong))
checkBounds "CULLong" boundedRange (approxBounds random trials (undefined:: CULLong))
checkBounds "CIntPtr" boundedRange (approxBounds random trials (undefined:: CIntPtr))
checkBounds "CUIntPtr" boundedRange (approxBounds random trials (undefined:: CUIntPtr))
checkBounds "CIntMax" boundedRange (approxBounds random trials (undefined:: CIntMax))
checkBounds "CUIntMax" boundedRange (approxBounds random trials (undefined:: CUIntMax))
-- Then check all the range-restricted versions:
checkBounds "Int R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined::Int))
checkBounds "Integer R"
(False,-100000000000000000000,100000000000000000000)
(approxBounds (randomR (-100000000000000000000,100000000000000000000)) trials (undefined::Integer))
checkBounds "Int8 R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined::Int8))
checkBounds "Int8 Rsmall" (False,-50,50) (approxBounds (randomR (-50,50)) trials (undefined::Int8))
checkBounds "Int8 Rmini" (False,3,4) (approxBounds (randomR (3,4)) trials (undefined::Int8))
checkBounds "Int8 Rtrivial" (False,3,3) (approxBounds (randomR (3,3)) trials (undefined::Int8))
checkBounds "Int16 R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined::Int16))
checkBounds "Int32 R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined::Int32))
checkBounds "Int64 R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined::Int64))
checkBounds "Word R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined::Word))
checkBounds "Word8 R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined::Word8))
checkBounds "Word16 R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined::Word16))
checkBounds "Word32 R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined::Word32))
checkBounds "Word64 R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined::Word64))
checkBounds "Double R" (False,10.0,77.0) (approxBounds (randomR (10,77)) trials (undefined::Double))
checkBounds "Float R" (False,10.0,77.0) (approxBounds (randomR (10,77)) trials (undefined::Float))
checkBounds "CChar R" (False,0,100) (approxBounds (randomR (0,100)) trials (undefined:: CChar))
checkBounds "CSChar R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined:: CSChar))
checkBounds "CUChar R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined:: CUChar))
checkBounds "CShort R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined:: CShort))
checkBounds "CUShort R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined:: CUShort))
checkBounds "CInt R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined:: CInt))
checkBounds "CUInt R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined:: CUInt))
checkBounds "CLong R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined:: CLong))
checkBounds "CULong R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined:: CULong))
checkBounds "CPtrdiff R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined:: CPtrdiff))
checkBounds "CSize R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined:: CSize))
checkBounds "CWchar R" (False,0,100) (approxBounds (randomR (0,100)) trials (undefined:: CWchar))
checkBounds "CSigAtomic R" (False,0,100) (approxBounds (randomR (0,100)) trials (undefined:: CSigAtomic))
checkBounds "CLLong R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined:: CLLong))
checkBounds "CULLong R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined:: CULLong))
checkBounds "CIntPtr R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined:: CIntPtr))
checkBounds "CUIntPtr R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined:: CUIntPtr))
checkBounds "CIntMax R" (False,-100,100) (approxBounds (randomR (-100,100)) trials (undefined:: CIntMax))
checkBounds "CUIntMax R" (False,0,200) (approxBounds (randomR (0,200)) trials (undefined:: CUIntMax))
-- Untested:
-- instance Random Char where
-- instance Random Bool where
-- instance Random Integer where