def initialize(data, document, options = {})
if options[:at].nil? || options[:at].empty?
raise Prawn::Errors::NoGraphStartSet,
"you must specify options[:at] as the coordinates where you" +
" wish this graph to be drawn from."
end
opts = { :theme => Prawn::Chart::Themes.monochrome, :width => 500, :height => 200, :spacing => 20 }.merge(options)
(@headings, @values, @highest_value) = process_the data
(grid_x_start, grid_y_start, grid_width, grid_height) = parse_sizing_from opts
@colour = (!opts[:use_color].nil? || !opts[:use_colour].nil?)
@document = document
@theme = opts[:theme]
off = 20
@grid = Prawn::Chart::Grid.new(grid_x_start, grid_y_start, grid_width, grid_height, opts[:spacing], document, @theme)
end