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GR framework - the graphics library for visualisation - for Ruby
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rdatasets-1 stem histogram barplot scatter3 volume griddata 2darray 2dpolararray hexbin rdatasets-2 rdatasets-3 surface face shade

📊 GR framework - powerful visualization library - for Ruby


GR.rb supports Ruby 2.5+.

First, install GR. Then install ruby-gr gem.

gem install ruby-gr

Note: If you are using RubyInstaller (Windows), pacman will automatically install mingw-w64-gr.

Set environment variable GRDIR.

export GRDIR="/your/path/to/gr"

If you use package managers to install GR, pkg-config may automatically detect the shared library location without specifying the GRDIR environment variable.

Quick Start

require 'gr/plot'

x = [0, 0.2, 0.4, 0.6, 0.8, 1.0]
y = [0.3, 0.5, 0.4, 0.2, 0.6, 0.7]

GR.plot(x, y)

require 'gr/plot'

x  = Numo::DFloat.linspace(0, 10, 101)
y1 = Numo::NMath.sin(x)
y2 = Numo::NMath.cos(x)

  [x, y1, 'bo'], [x, y2, 'g*'],
  title:    "Multiple plot example",
  xlabel:   "x",
  ylabel:   "y",
  ylim:     [-1.2, 1.2],
  labels:   ["sin(x)", "cos(x)"],
  location: 11

Save the figure in PNG format.


API Overview

There are two different approaches when plotting with GR.rb. One is to call Matlab-like APIs. The other is to call GR/GR3 native functions.

GR::Plot - A simple, matlab-style API.

require 'gr/plot'
GR.plot(x, y)

Below are a list of available functions. See GR.rb Wiki for details. Some GR module methods are overwritten.

plot step plot3 polar scatter scatter3 stem barplot histogram polarhistogram hexbin contour contourf tricont surface trisurf wireframe volume heatmap polarheatmap shade imshow isosurface

We are preparing a more object-oriented interface based on GRUtils.jl in the future.

GR - A module for calling native GR functions.

2-D Plots and common 3-D Plots.

require 'gr'

# For example
GR.setviewport(0.1, 0.9, 0.1, 0.9)
GR.setwindow(0.0, 20.0, 0.0, 20.0)

GR3 - A module for calling native GR3 functions.

Complex 3D scenes.

require 'gr3'

# For example
GR3.cameralookat(-3, 2, -2, 0, 0, 0, 0, 0, -1)


Although GR.rb adds methods dynamically, we try our best to provide a complete yard document. If you want to see more up-to-date information, we recommend using the official GR reference.

GR Installation

Installing an official release (recommended)

Download the latest release.

Set environment variable GRDIR.

export GRDIR="your/path/to/gr"
  • macOS Catalina and macOS Mojave: See the "How to open an app that hasn’t been notarized or is from an unidentified developer" section under Safely open apps on your Mac in the Apple documentation.

Using package managers

  • The third party GR packages for Mac, Linux and Windows are available (for advanced users).
  • If you find any problem, please report the issue here.
  • Note: These packages may not have some features such as video output.

Mac - Homebrew

brew install libgr
# brew install --build-from-source libgr

Linux - APT provides libgr-dev, libgr3-dev and libgrm-dev

Debian GNU/Linux and Ubuntu

sudo apt install -y -V ca-certificates lsb-release wget
wget$(lsb_release --id --short | tr 'A-Z' 'a-z')/red-data-tools-apt-source-latest-$(lsb_release --codename --short).deb
sudo apt install -y -V ./red-data-tools-apt-source-latest-$(lsb_release --codename --short).deb
sudo apt update
sudo apt install libgrm-dev

Linux - Yum


(. /etc/os-release && sudo dnf install -y${VERSION_ID}/red-data-tools-release-latest.noarch.rpm)
sudo dnf install -y gr-devel

Windows - MSYS2

If you are using Rubyinstaller, pacman will automatically install mingw-w64-gr when the gem is installed.

Backend for Charty

GR.rb will be the default backend for Charty.


GR.rb is a library under development, so even small improvements like fixing typos are welcome! Please feel free to send us your PR.

  • Report bugs
  • Fix bugs and submit pull requests
  • Write, clarify, or fix documentation
  • Suggest or add new features
  • Update GR packages ( Homebrew, MinGW, red-data-tools )
  • Create visualization tools based on GR.rb


We would like to thank Josef Heinen, the creator of GR and GR.jl, Florian Rhiem, the creator of python-gr, and all GR developers.