This library enables to directly call matplotlib from Ruby language. This is built on top of pycall.


Add this line to your application's Gemfile:

gem 'matplotlib'

And then execute:

$ bundle

Or install it yourself as:

$ gem install --pre matplotlib


Using pyplot in irb console or standalone scripts

Example usage:

require 'matplotlib/pyplot'
plt = Matplotlib::Pyplot

xs = [*1..100].map {|x| (x - 50) * Math::PI / 100.0 }
ys = {|x| Math.sin(x) }

plt.plot(xs, ys)

IRuby integration

matplotlib/iruby provides integration between IRuby notebook and matplotlib. This functionality can be enabled by calling Matplotlib::IRuby.activate.

require 'matplotlib/iruby'

matplotlib/iruby also loads matplotlib/pyplot, so you can use Matplotlib::Pyplot module without explicitly requiring matplotlib/pyplot. And this introduces a post execution hook which put figures that are created in a cell just below the execution result of the cell.

See ipynb files in examples to see example usages.


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


Bug reports and pull requests are welcome on GitHub at


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