Mathn

mathn serves to make mathematical operations more precise in Ruby and to integrate other mathematical standard libraries.

Without mathn:

3 / 2 => 1 # Integer

With mathn:

require "mathn"
using Math::N
3 / 2 => 3/2 # Rational

mathn keeps value in exact terms.

Without mathn:

20 / 9 * 3 * 14 / 7 * 3 / 2 # => 18

With mathn:

require "mathn"
using Math::N
20 / 9 * 3 * 14 / 7 * 3 / 2 # => 20

Global Behavioral Changes

While older version of 'mathn', just by required, caused changes to the behavior (and even the types) of operations on classes like Integer, newer mathn introduces the refinements Math::N, and you have to enable it.

Before ruby 2.5, mathn was part of the ruby standard library. It was deprecated in ruby 2.2.0, and removed from ruby 2.5.0. In order to use the library with a current version of ruby, you must install it as a gem.

Installation

Add this line to your application's Gemfile:

gem 'mathn'

And then execute:

$ bundle

Or install it yourself as:

$ gem install mathn

Usage

require 'mathn'
using Math::N

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/ruby/mathn.

License

The gem is available as open source under the terms of the MIT License.