probability: Probabilistic Functional Programming

[ bsd3, graphics, library, math, monads ] [ Propose Tags ]

The Library allows exact computation with discrete random variables in terms of their distributions by using a monad. The monad is similar to the List monad for non-deterministic computations, but extends the List monad by a measure of probability. Small interface to R plotting.

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Versions [faq] 0.1, 0.2, 0.2.1, 0.2.2,, 0.2.3,, 0.2.4,, 0.2.5,,
Dependencies base, mtl [details]
License BSD-3-Clause
Author Martin Erwig <>, Steve Kollmansberger
Maintainer Henning Thielemann <>
Category Math, Monads, Graphics
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Uploaded by HenningThielemann at Sun Feb 17 22:01:58 UTC 2008
Distributions FreeBSD:, LTSHaskell:, NixOS:, Stackage:
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  • Numeric
    • Probability
      • Numeric.Probability.Distribution
      • Example
        • Numeric.Probability.Example.Alarm
        • Numeric.Probability.Example.Barber
        • Numeric.Probability.Example.Bayesian
        • Numeric.Probability.Example.Boys
        • Numeric.Probability.Example.Collection
        • Numeric.Probability.Example.Diagnosis
        • Numeric.Probability.Example.Dice
        • Numeric.Probability.Example.DiceAccum
        • Numeric.Probability.Example.MontyHall
        • Numeric.Probability.Example.NBoys
        • Numeric.Probability.Example.Predator
        • Numeric.Probability.Example.Queuing
        • Numeric.Probability.Example.TreeGrowth
      • Numeric.Probability.Expectation
      • Numeric.Probability.Object
      • Numeric.Probability.Percentage
      • Numeric.Probability.Random
      • Numeric.Probability.Shape
      • Numeric.Probability.Simulation
      • Numeric.Probability.Trace
      • Numeric.Probability.Transition
      • Numeric.Probability.Visualize


Maintainer's Corner

For package maintainers and hackage trustees

Readme for probability-0.2

[back to package description]
Probabilistic Functional Programming in Haskell

Martin Erwig, Oregon State University,

These files have been tested with GHC 6.4

Core Library files:

Show.hs		Pretty Printing
Probability.hs	Core probabilistic module
Visualize.hs	Visualization system for use with R


Barber.hs		An example of the queueing system
BayesianNetwork.hs	Implementing Bayesian networks
Boys.hs			A statistical examples
NBoys.hs		A generalized version of the previous
Collection.hs		Collections and two examples:
			Marbles and cards
Dice.hs			Rolling dice
MontyHall.hs		The "Monty Hall" Game (statistical)
Predator.hs		Non-probabilistic, demonstrates visualization
TreeGrowth.hs		A simple tree growth example

Visualize output is placed in the file FuSE.R which can be loaded into the 
R statistical program to see visualizations.

Randomized values can be displayed to the console using the printR 
function, which shows the value from a IO monad function.