random is:package

Pseudo-random number generation This package provides basic pseudo-random number generation, including the ability to split random number generators.

System.Random: pure pseudo-random number interface

In pure code, use System.Random.uniform and System.Random.uniformR from System.Random to generate pseudo-random numbers with a pure pseudo-random number generator like System.Random.StdGen. As an example, here is how you can simulate rolls of a six-sided die using System.Random.uniformR:

>>> let roll = uniformR (1, 6)        :: RandomGen g => g -> (Word, g)

>>> let rolls = unfoldr (Just . roll) :: RandomGen g => g -> [Word]

>>> let pureGen = mkStdGen 42

>>> take 10 (rolls pureGen)           :: [Word]
[1,1,3,2,4,5,3,4,6,2]

See System.Random for more details.

System.Random.Stateful: monadic pseudo-random number interface

In monadic code, use System.Random.Stateful.uniformM and System.Random.Stateful.uniformRM from System.Random.Stateful to generate pseudo-random numbers with a monadic pseudo-random number generator, or using a monadic adapter. As an example, here is how you can simulate rolls of a six-sided die using System.Random.Stateful.uniformRM:

>>> let rollM = uniformRM (1, 6)                 :: StatefulGen g m => g -> m Word

>>> let pureGen = mkStdGen 42

>>> runStateGen_ pureGen (replicateM 10 . rollM) :: [Word]
[1,1,3,2,4,5,3,4,6,2]

The monadic adapter System.Random.Stateful.runStateGen_ is used here to lift the pure pseudo-random number generator pureGen into the System.Random.Stateful.StatefulGen context. The monadic interface can also be used with existing monadic pseudo-random number generators. In this example, we use the one provided in the mwc-random package:

>>> import System.Random.MWC as MWC

>>> let rollM = uniformRM (1, 6)       :: StatefulGen g m => g -> m Word

>>> monadicGen <- MWC.create

>>> replicateM 10 (rollM monadicGen) :: IO [Word]
[2,3,6,6,4,4,3,1,5,4]

See System.Random.Stateful for more details.

Random shuffle implementation. Random shuffle implementation, on immutable lists. Based on `perfect shuffle' implementation by Oleg Kiselyov, available on http:okmij.orgftpHaskell/perfect-shuffle.txt

Random number generation Random number generation based on modeling random variables in two complementary ways: first, by the parameters of standard mathematical distributions and, second, by an abstract type (RVar) which can be composed and manipulated monadically and sampled in either monadic or "pure" styles. The primary purpose of this library is to support defining and sampling a wide variety of high quality random variables. Quality is prioritized over speed, but performance is an important goal too. In my testing, I have found it capable of speed comparable to other Haskell libraries, but still a fair bit slower than straight C implementations of the same algorithms.

Not on Stackage, so not searched. Generic basis for random number generators

Not on Stackage, so not searched. Generate random strings with specific qualities

Efficient generation of random bytestrings This package is deprecated. Please, use genByteString from the random package (version >=1.2) instead. Efficient generation of random bytestrings. The implementation populates uninitialized memory with uniformily distributed random 64 bit words (and 8 bit words for remaining bytes at the end of the bytestring). Random words are generated using the PRNG from the mwc-random package or the pcg-random package. It is also possible to use a custom PRNG by providing an instance for the RandomWords type class and using the function generate from the module Data.ByteString.Random.Internal. The generated byte strings are suitable for statistical applications. They are not suitable for cryptographic applications.

Not on Stackage, so not searched. Additional functions for random values.

Not on Stackage, so not searched. Random file access methods, supporting application-level page cache.

Not on Stackage, so not searched. Multivariate distributions for random-fu

Not on Stackage, so not searched. Random-access lists in Haskell

Not on Stackage, so not searched. Class of random value generation

Not on Stackage, so not searched. Uniform draws of partitions and cycle-partitions, with thinning.

Not on Stackage, so not searched. A Template Haskell helper for deriving Random instances

Not on Stackage, so not searched. A simple random generator library for extensible-effects

Not on Stackage, so not searched. A simple random generator library for effin

Not on Stackage, so not searched. Random variate generation from hypergeometric distributions

Not on Stackage, so not searched. Expose Random and Arbitrary instances

Not on Stackage, so not searched. An infinite stream of random data

Not on Stackage, so not searched. Generate a random base 16, 58, or 64 string

Create random trees Create random trees

Not on Stackage, so not searched. "Uniform RNG => Non-Uniform RNGs"

Not on Stackage, so not searched. A fast, SMP parallel random data generator

Not on Stackage, so not searched. Haskell port of Random123 library

Not on Stackage, so not searched. Haskell bindings to the RANDOM.ORG Core API

Not on Stackage, so not searched. Randomness intuition trainer