Generate graphs in PDFs

README.md

The libtiff steps might not be necessary, but to get everything working, I did:

brew install libtiff
brew install ghostscript
brew install imagemagick --with-libtiff

Gemfile

source 'https://rubygems.org'

gem 'prawn'
gem 'gruff'

main.rb

Bundler.require(:default)

g = Gruff::Line.new
g.title = 'My Graph'

g.data('Apples', [1, 2, 3, 4, 4, 3])
g.data('Oranges', [4, 8, 7, 9, 8, 9])
g.data('Watermelon', [2, 3, 1, 5, 6, 8])
g.data('Peaches', [9, 9, 10, 8, 7, 9])

g.labels = {0 => '2003', 2 => '2004', 4 => '2005'}

Prawn::Document.generate('example.pdf') do |pdf|
  pdf.text 'Graph Example'
  pdf.image StringIO.new(g.to_blob), :fit => [pdf.bounds.width, pdf.bounds.height]
end