Vose: Sample random values from a discrete probability distribution.
Vose is a Ruby implementation of the Vose Alias Method. It allows for sampling of random values from a discrete probability distribution. In simpler terms, this gem simulates a loaded die. This implementation runs in O(1) time after after a O(n) initialization.
For more information on the theory, have a look at Darts, Dice, and Coins: Sampling from a Discrete Distribution
Installation
To track the latest officially released gem:
gem 'vose' # for the latest officially released gem
OR To track the git repo
gem 'vose', :git => "git://github.com/thunderboltlabs/vose.git"
And then execute:
$ bundle
Or install it yourself as:
$ gem install vose
Usage
probabilities = [0.4, 0.1, 0.2, 0.3]
vose = Vose::AliasMethod.new probabilities
choice = vose.next # => an int
The choice will be an index of the probabilities array.
Contributing
- Fork it
- Create your feature branch (
git checkout -b my-new-feature
) - Commit your changes (
git commit -am 'Added some feature'
) - Push to the branch (
git push origin my-new-feature
) - Create new Pull Request