Class: Gruff::Dot

Inherits:

Base

• Object
• Base
• Gruff::Dot

Defined in:

lib/gruff/dot.rb

Overview

Graph with dots and labels along a vertical access. see: ‘Creating More Effective Graphs’ by Robbins

Here’s how to set up a Gruff::Dot.

g = Gruff::Dot.new
g.title = 'Dot Graph'
g.data :Art, [0, 5, 8, 15]
g.data :Philosophy, [10, 3, 2, 8]
g.data :Science, [2, 15, 8, 11]
g.write('dot.png')

Constant Summary

Constants inherited from Base

Base::DEFAULT_MARGIN, Base::DEFAULT_TARGET_WIDTH, Base::LABEL_MARGIN, Base::LEGEND_MARGIN

Instance Attribute Summary

Attributes inherited from Base

#bold_title, #bottom_margin, #center_labels_over_point, #colors, #font_color, #has_left_labels, #hide_legend, #hide_line_markers, #hide_line_numbers, #hide_title, #label_max_size, #label_stagger_height, #label_truncation_style, #labels, #left_margin, #legend_at_bottom, #legend_box_size, #legend_font_size, #legend_margin, #marker_color, #marker_font_size, #marker_shadow_color, #maximum_value, #minimum_value, #no_data_message, #right_margin, #sort, #sorted_drawing, #title, #title_font, #title_font_size, #title_margin, #top_margin, #use_data_label, #x_axis_increment, #x_axis_label, #y_axis_increment, #y_axis_label

Instance Method Summary

• #draw ⇒ Object

Methods inherited from Base

#add_color, #data, #font=, #initialize, #margins=, #replace_colors, #theme=, #theme_37signals, #theme_greyscale, #theme_keynote, #theme_odeo, #theme_pastel, #theme_rails_keynote, #to_blob, #to_image, #write

Constructor Details

This class inherits a constructor from Gruff::Base

Instance Method Details

#draw ⇒ Object

# File 'lib/gruff/dot.rb', line 17

def draw
  @has_left_labels = true
  super

  return unless data_given?

  # Setup spacing.
  #
  spacing_factor = 1.0

  items_width = @graph_height / column_count.to_f
  item_width = items_width * spacing_factor / store.length
  padding = (items_width * (1 - spacing_factor)) / 2

  store.norm_data.each_with_index do |data_row, row_index|
    data_row.points.each_with_index do |data_point, point_index|
      x_pos = @graph_left + (data_point * @graph_width)
      y_pos = @graph_top + (items_width * point_index) + padding + (items_width.to_f / 2.0).round

      if row_index == 0
        Gruff::Renderer::Line.new(color: @marker_color).render(@graph_left, y_pos, @graph_left + @graph_width, y_pos)
      end

      Gruff::Renderer::Circle.new(color: data_row.color).render(x_pos, y_pos, x_pos + (item_width.to_f / 3.0).round, y_pos)

      draw_label(y_pos, point_index)
    end
  end
end