get_y_labels (SVG::Graph::Line)

    # File temp/Graph/Line.rb, line 150
          def get_y_labels
            max_value = @data.collect{|x| x[:data].max}.max
            min_value = @data.collect{|x| x[:data].min}.min
            range = max_value - min_value
            top_pad = range == 0 ? 10 : range / 20.0
            scale_range = (max_value + top_pad) - min_value

            scale_division = scale_divisions || (scale_range / 10.0)

            if scale_integers
              scale_division = scale_division < 1 ? 1 : scale_division.round
            end

            rv = []
            max_value = max_value%scale_division == 0 ?
              max_value : max_value + scale_division
            min_value.step( max_value, scale_division ) {|v| rv << v}
            return rv
          end