Parses a mathematical expression from infix notation into reverse polish notation and produces a result.

Add this line to your application's Gemfile:

gem 'math_expr'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install math_expr

require 'math_expression/parser'

parser = MathExpression::Parser.new('4 + 5')

parser.to_tokens # => [{:type=>:number, :value=>4}, {:type=>:operator, :value=>"+"}, {:type=>:number, :value=>5}]

parser.to_postfix # => [4, 5, "+"]

parser.evaluate # => 9

After checking out the repo, run bin/setup to install dependencies. Then, run rake respec 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.

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

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