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] } )
# File lib/SVG/Graph/Pie.rb, line 111 def add_data arg arg[:data].each_index {|idx| @data[idx] = 0 unless @data[idx] @data[idx] += arg[:data][idx] } 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 147 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 187 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 = (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 } percent_scale = 100.0 / total prev_percent = 0 rad_mult = 3.6 * RADIANS @config[:fields].each_index { |count| value = @data[count] percent = percent_scale * value radians = prev_percent * rad_mult 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 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 prev_percent += percent } end
We don't need the graph
# File lib/SVG/Graph/Pie.rb, line 160 def draw_graph end
# File lib/SVG/Graph/Pie.rb, line 308 def get_css return <<EOL .dataPointLabel{ fill: #000000; text-anchor:middle; font-size: #{datapoint_font_size}px; font-family: "Arial", sans-serif; font-weight: normal; } /* 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
# File lib/SVG/Graph/Pie.rb, line 167 def get_x_labels [""] end
# File lib/SVG/Graph/Pie.rb, line 163 def get_y_labels [""] end
# File lib/SVG/Graph/Pie.rb, line 171 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+"%" : "" x + " [" + v.to_s + "]" + perc } end
# File lib/SVG/Graph/Pie.rb, line 302 def round val, to up = 10**to.to_f (val * up).to_i / up end