class SVG::Graph::Pie
Create presentation quality SVG
pie graphs easily¶ ↑
Synopsis¶ ↑
require 'SVG/Graph/Pie' fields = %w(Jan Feb Mar) data_sales_02 = [12, 45, 21] graph = SVG::Graph::Pie.new({ :height => 500, :width => 300, :fields => fields, }) graph.add_data({ :data => data_sales_02, :title => 'Sales 2002', }) print "Content-type: image/svg+xml\r\n\r\n" print graph.burn();
Description¶ ↑
This object aims to allow you to easily create high quality SVG
pie graphs. You can either use the default style sheet or supply your own. Either way there are many options which can be configured to give you control over how the graph is generated - with or without a key, display percent on pie chart, title, subtitle etc.
Examples¶ ↑
www.germane-software/repositories/public/SVG/test/single.rb
See also¶ ↑
Author¶ ↑
Sean E. Russell <serATgermaneHYPHENsoftwareDOTcom>
Copyright 2004 Sean E. Russell This software is available under the Ruby license
Constants
- RADIANS
Attributes
The font size of the data point labels
The amount of space between expanded wedges
If true, expand the largest pie wedge
If true, “explode” the pie (put space between the wedges)
Sets the offset of the shadow from the pie chart
If true, display the actual field values in the data labels
If true, display the data labels on the chart
If true, display the actual value of the field in the key
If true, display the labels in the key
If true, display the percentage value of the wedges in the key
If true, display the percentage value of each pie wedge in the data labels
If true, displays a drop shadow for the chart
Public Instance Methods
Adds a data set to the graph.
graph.add_data( { :data => [1,2,3,4] } )
Note that the :title is not necessary. If multiple data sets are added to the graph, the pie chart will display the sums
of the data. EG:
graph.add_data( { :data => [1,2,3,4] } ) graph.add_data( { :data => [2,3,5,9] } )
is the same as:
graph.add_data( { :data => [3,5,8,13] } )
nil values in the array will be replaced by 0
graph.add_data( { :data => [3,nil,nil,2] } ) is equivalent to graph.add_data( { :data => [3,0,0,2] } )
# File lib/SVG/Graph/Pie.rb, line 116 def add_data arg arg[:data].each_index {|idx| @data[idx] = 0 unless @data[idx] if !arg[:data][idx].nil? @data[idx] += arg[:data][idx] end } end
Defaults are those set by Graph::initialize, and
show_shadow
-
true
shadow_offset
-
10
show_data_labels
-
false
show_actual_values
-
false
show_percent
-
true
show_key_data_labels
-
true
show_key_actual_values
-
true
show_key_percent
-
false
- expanded
-
false
expand_greatest
-
false
expand_gap
-
10
- show_x_labels
-
false
- show_y_labels
-
false
datapoint_font_size
-
12
# File lib/SVG/Graph/Pie.rb, line 73 def set_defaults init_with( :show_shadow => true, :shadow_offset => 10, :show_data_labels => false, :show_actual_values => false, :show_percent => true, :show_key_data_labels => true, :show_key_actual_values => true, :show_key_percent => false, :expanded => false, :expand_greatest => false, :expand_gap => 10, :show_x_labels => false, :show_y_labels => false, :datapoint_font_size => 12 ) @data = [] end
Protected Instance Methods
# File lib/SVG/Graph/Pie.rb, line 154 def add_defs defs gradient = defs.add_element( "filter", { "id"=>"dropshadow", "width" => "1.2", "height" => "1.2", } ) gradient.add_element( "feGaussianBlur", { "stdDeviation" => "4", "result" => "blur" }) end
# File lib/SVG/Graph/Pie.rb, line 197 def draw_data @graph = @root.add_element( "g" ) background = @graph.add_element("g") midground = @graph.add_element("g") diameter = @graph_height > @graph_width ? @graph_width : @graph_height diameter -= expand_gap if expanded or expand_greatest diameter -= datapoint_font_size if show_data_labels diameter -= 10 if show_shadow radius = diameter / 2.0 xoff = (@graph_width - diameter) / 2 yoff = (height - @border_bottom - diameter) yoff -= 10 if show_shadow @graph.attributes['transform'] = "translate( #{xoff} #{yoff} )" wedge_text_pad = 5 wedge_text_pad = 20 if show_percent and show_data_labels total = 0 max_value = 0 @data.each {|x| max_value = max_value < x ? x : max_value total += x } prev_percent = 0 rad_mult = 3.6 * RADIANS @config[:fields].each_index { |count| value = @data[count].to_f percent = total.zero? ? 0.0 : 100.0 * value / total radians = prev_percent * rad_mult if percent.rationalize(0.001) == 100.0 @foreground.add_element( "circle", { "cx" => radius.to_s, "cy" => radius.to_s, "r" => radius.to_s, "class" => "fill#{count+1}" }) if show_shadow shadow = background.add_element( "circle", { "cx" => radius.to_s, "cy" => radius.to_s, "r" => radius.to_s, "filter" => "url(#dropshadow)", "style" => "fill: #ccc; stroke: none;" }) clear = midground.add_element( "circle", { "cx" => radius.to_s, "cy" => radius.to_s, "r" => radius.to_s, "style" => "fill: #fff; stroke: none;" }) shadow.attributes["transform"] = "translate( #{shadow_offset} #{shadow_offset} )" end else x_start = radius+(Math.sin(radians) * radius) y_start = radius-(Math.cos(radians) * radius) radians = (prev_percent+percent) * rad_mult x_end = radius+(Math.sin(radians) * radius) x_end -= 0.00001 if @data.length == 1 y_end = radius-(Math.cos(radians) * radius) path = "M#{radius},#{radius} L#{x_start},#{y_start} "+ "A#{radius},#{radius} "+ "0, #{percent >= 50 ? '1' : '0'},1, "+ "#{x_end} #{y_end} Z" wedge = @foreground.add_element( "path", { "d" => path, "class" => "fill#{count+1}" }) translate = nil tx = 0 ty = 0 half_percent = prev_percent + percent / 2 radians = half_percent * rad_mult if show_shadow shadow = background.add_element( "path", { "d" => path, "filter" => "url(#dropshadow)", "style" => "fill: #ccc; stroke: none;" }) clear = midground.add_element( "path", { "d" => path, "style" => "fill: #fff; stroke: none;" }) end if expanded or (expand_greatest && value == max_value) tx = (Math.sin(radians) * expand_gap) ty = -(Math.cos(radians) * expand_gap) translate = "translate( #{tx} #{ty} )" wedge.attributes["transform"] = translate clear.attributes["transform"] = translate if clear end if show_shadow shadow.attributes["transform"] = "translate( #{tx+shadow_offset} #{ty+shadow_offset} )" end prev_percent += percent end if show_data_labels and value != 0 label = "" label += @config[:fields][count] if show_key_data_labels label += " ["+value.to_s+"]" if show_actual_values label += " "+percent.round.to_s+"%" if show_percent msr = Math.sin(radians) mcr = Math.cos(radians) tx = radius + (msr * radius) ty = radius - (mcr * radius) if expanded or (expand_greatest && value == max_value) tx += (msr * expand_gap) ty -= (mcr * expand_gap) end @foreground.add_element( "text", { "x" => tx.to_s, "y" => ty.to_s, "class" => "dataPointLabel", "style" => "stroke: #fff; stroke-width: 2;" }).text = label.to_s @foreground.add_element( "text", { "x" => tx.to_s, "y" => ty.to_s, "class" => "dataPointLabel", }).text = label.to_s end } end
We don't need the graph
# File lib/SVG/Graph/Pie.rb, line 167 def draw_graph end
# File lib/SVG/Graph/Pie.rb, line 344 def get_css return <<EOL .dataPointLabel, .dataPointLabelBackground, .dataPointPopup{ fill: #000000; text-anchor:middle; font-size: #{datapoint_font_size}px; font-family: "Arial", sans-serif; font-weight: normal; } .dataPointLabelBackground{ stroke: #ffffff; stroke-width: 2; } .dataPointPopup{ fill: #000000; visibility: hidden; stroke-width: 2; } /* key - MUST match fill styles */ .key1,.fill1{ fill: #ff0000; fill-opacity: 0.7; stroke: none; stroke-width: 1px; } .key2,.fill2{ fill: #0000ff; fill-opacity: 0.7; stroke: none; stroke-width: 1px; } .key3,.fill3{ fill-opacity: 0.7; fill: #00ff00; stroke: none; stroke-width: 1px; } .key4,.fill4{ fill-opacity: 0.7; fill: #ffcc00; stroke: none; stroke-width: 1px; } .key5,.fill5{ fill-opacity: 0.7; fill: #00ccff; stroke: none; stroke-width: 1px; } .key6,.fill6{ fill-opacity: 0.7; fill: #ff00ff; stroke: none; stroke-width: 1px; } .key7,.fill7{ fill-opacity: 0.7; fill: #00ff99; stroke: none; stroke-width: 1px; } .key8,.fill8{ fill-opacity: 0.7; fill: #ffff00; stroke: none; stroke-width: 1px; } .key9,.fill9{ fill-opacity: 0.7; fill: #cc6666; stroke: none; stroke-width: 1px; } .key10,.fill10{ fill-opacity: 0.7; fill: #663399; stroke: none; stroke-width: 1px; } .key11,.fill11{ fill-opacity: 0.7; fill: #339900; stroke: none; stroke-width: 1px; } .key12,.fill12{ fill-opacity: 0.7; fill: #9966FF; stroke: none; stroke-width: 1px; } EOL end
We don't have axis labels
# File lib/SVG/Graph/Pie.rb, line 176 def get_x_labels [""] end
We don't have axis labels
# File lib/SVG/Graph/Pie.rb, line 171 def get_y_labels [""] end
# File lib/SVG/Graph/Pie.rb, line 180 def keys total = 0 #max_value = 0 @data.each {|x| total += x } percent_scale = 100.0 / total count = -1 @config[:fields].collect{ |x| count += 1 v = @data[count] perc = show_key_percent ? " "+(v * percent_scale).round.to_s+"%" : "" val = show_key_actual_values ? " [" + v.to_s + "]" : "" x + val + perc } end
# File lib/SVG/Graph/Pie.rb, line 338 def round val, to up = 10**to.to_f (val * up).to_i / up end