| Portability | portable |
|---|---|
| Stability | experimental |
| Safe Haskell | Safe-Infered |
Data.Random.Extras
Contents
Description
Additional monadic random functions, based on random-fu.
- shuffle :: [a] -> RVar [a]
- shuffleSeq :: Seq a -> RVar [a]
- sample :: Int -> [a] -> RVar [a]
- sampleSeq :: Int -> Seq a -> RVar [a]
- choiceExtract :: [a] -> Maybe (RVar ([a], a))
- choiceExtractSeq :: Seq a -> Maybe (RVar (Seq a, a))
- choice :: [a] -> RVar a
- safeChoice :: [a] -> Maybe (RVar a)
- iterativeChoice :: [a] -> RVar a
- choiceSeq :: Seq a -> RVar a
- safeChoiceSeq :: Seq a -> Maybe (RVar a)
- choiceArray :: (IArray arr a, Ix i, Distribution Uniform i) => arr i a -> RVar a
- choices :: Int -> [a] -> RVar [a]
- safeChoices :: Int -> [a] -> Maybe (RVar [a])
- choicesArray :: (IArray arr a, Ix i, Distribution Uniform i) => Int -> arr i a -> RVar [a]
Random functions
Shuffling
shuffle :: [a] -> RVar [a]Source
Shuffle a list randomly. The method is based on Oleg Kiselyov's perfect shuffle http://okmij.org/ftp/Haskell/perfect-shuffle.txt, but much simpler because it uses existing data structures. The efficiency of both methods should be comparable.
Complexity: O(n * log n), where n is the length of the input list.
shuffleSeq :: Seq a -> RVar [a]Source
Shuffle a sequence randomly. This is being used by shuffle,
so it logically uses the same method.
Complexity: O(n * log n), where n is the length of the input sequence.
Sampling
sample :: Int -> [a] -> RVar [a]Source
Take a random sample from a list.
Complexity: O(n + m * log n), where n is the length of the input list and m is the sample size.
sampleSeq :: Int -> Seq a -> RVar [a]Source
Take a random sample from a sequence.
Complexity: O(m * log n), where n is the length of the input sequence and m is the sample size.
Choice
choiceExtract :: [a] -> Maybe (RVar ([a], a))Source
Randomly choose and extract an element from a list.
Complexity: O(n), where n is the length of the input list.
choiceExtractSeq :: Seq a -> Maybe (RVar (Seq a, a))Source
Randomly choose and extract an element from a sequence.
Complexity: O(log n), where n is the length of the input sequence.
Select a random element from a list.
Partial function: This function is only defined on non-empty lists.
Complexity: O(n), where n is the length of the input list.
safeChoice :: [a] -> Maybe (RVar a)Source
Safely select a random element from a list.
Complexity: O(n), where n is the length of the input list.
iterativeChoice :: [a] -> RVar aSource
Select a random element from a list, traversing the list only once.
Partial function: This function is only defined on non-empty lists
with a length below (maxBound + 1 :: Int).
Complexity: O(n), where n is the length of the input list.
choiceSeq :: Seq a -> RVar aSource
Select a random element from a sequence.
Partial function: This function is only defined on non-empty sequences.
Complexity: O(log n), where n is the length of the input sequence.
safeChoiceSeq :: Seq a -> Maybe (RVar a)Source
Safely select a random element from a sequence.
Complexity: O(log n), where n is the length of the input sequence.
choiceArray :: (IArray arr a, Ix i, Distribution Uniform i) => arr i a -> RVar aSource
Select a random element from an array.
Complexity: O(1).
Choices
choices :: Int -> [a] -> RVar [a]Source
A stream of random elements from a list.
Partial function: This function is only defined on non-empty lists.
Complexity: O(n) base and O(1) per element.
safeChoices :: Int -> [a] -> Maybe (RVar [a])Source
Safely get a stream of random elements from a list.
Complexity: O(n) base and O(1) per element, where n is the length of the input list.
choicesArray :: (IArray arr a, Ix i, Distribution Uniform i) => Int -> arr i a -> RVar [a]Source
A stream of random elements from an array.
Complexity: O(1) per element.