class SVG::Graph::Line
Create presentation quality SVG line graphs easily¶ ↑
Synopsis¶ ↑
require 'SVG/Graph/Line' fields = %w(Jan Feb Mar); data_sales_02 = [12, 45, 21] data_sales_03 = [15, 30, 40] graph = SVG::Graph::Line.new({ :height => 500, :width => 300, :fields => fields, }) graph.add_data({ :data => data_sales_02, :title => 'Sales 2002', }) graph.add_data({ :data => data_sales_03, :title => 'Sales 2003', }) 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 line 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, data elements at each point, title, subtitle etc.
Examples¶ ↑
www.germane-software/repositories/public/SVG/test/single.rb
Notes¶ ↑
The default stylesheet handles upto 10 data sets, if you use more you must create your own stylesheet and add the additional settings for the extra data sets. You will know if you go over 10 data sets as they will have no style and be in black.
See also¶ ↑
Author¶ ↑
Sean E. Russell <serATgermaneHYPHENsoftwareDOTcom>
Copyright 2004 Sean E. Russell This software is available under the Ruby license
Attributes
Fill in the area under the plot if true
Show a small circle on the graph where the line goes from one point to the next.
Accumulates each data set. (i.e. Each point increased by sum of
all previous series at same point). Default is 0, set to '1' to show.
Public Class Methods
The constructor takes a hash reference, fields (the names for each field on the X axis) MUST be set, all other values are defaulted to those shown above - with the exception of style_sheet which defaults to using the internal style sheet.
# File lib/SVG/Graph/Line.rb, line 85 def initialize config raise "fields was not supplied or is empty" unless config[:fields] && config[:fields].kind_of?(Array) && config[:fields].length > 0 super end
Public Instance Methods
In addition to the defaults set in Graph::initialize, sets
- #show_data_points
-
true
- show_data_values
-
true
- stacked
-
false
- #area_fill
-
false
# File lib/SVG/Graph/Line.rb, line 97 def set_defaults init_with( :show_data_points => true, :show_data_values => true, :stacked => false, :area_fill => false ) self.top_align = self.top_font = self.right_align = self.right_font = 1 end
Protected Instance Methods
# File lib/SVG/Graph/Line.rb, line 175 def calc_coords(field, value, width = field_width, height = field_height) coords = {:x => 0, :y => 0} coords[:x] = width * field coords[:y] = @graph_height - value * height return coords end
# File lib/SVG/Graph/Line.rb, line 149 def calculate_left_margin super label_left = @config[:fields][0].length / 2 * font_size * 0.6 @border_left = label_left if label_left > @border_left end
# File lib/SVG/Graph/Line.rb, line 183 def draw_data minvalue = min_value fieldheight = (@graph_height.to_f - font_size*2*top_font) / (get_y_labels.max - get_y_labels.min) fieldwidth = field_width line = @data.length prev_sum = Array.new(@config[:fields].length).fill(0) cum_sum = Array.new(@config[:fields].length).fill(-minvalue) for data in @data.reverse lpath = "" apath = "" if not stacked then cum_sum.fill(-minvalue) end data[:data].each_index do |i| cum_sum[i] += data[:data][i] c = calc_coords(i, cum_sum[i], fieldwidth, fieldheight) lpath << "#{c[:x]} #{c[:y]} " end if area_fill if stacked then (prev_sum.length - 1).downto 0 do |i| c = calc_coords(i, prev_sum[i], fieldwidth, fieldheight) apath << "#{c[:x]} #{c[:y]} " end c = calc_coords(0, prev_sum[0], fieldwidth, fieldheight) else apath = "V#@graph_height" c = calc_coords(0, 0, fieldwidth, fieldheight) end @graph.add_element("path", { "d" => "M#{c[:x]} #{c[:y]} L" + lpath + apath + "Z", "class" => "fill#{line}" }) end @graph.add_element("path", { "d" => "M0 #@graph_height L" + lpath, "class" => "line#{line}" }) if show_data_points || show_data_values cum_sum.each_index do |i| if show_data_points @graph.add_element( "circle", { "cx" => (fieldwidth * i).to_s, "cy" => (@graph_height - cum_sum[i] * fieldheight).to_s, "r" => "2.5", "class" => "dataPoint#{line}" }) end make_datapoint_text( fieldwidth * i, @graph_height - cum_sum[i] * fieldheight - 6, cum_sum[i] + minvalue ) end end prev_sum = cum_sum.dup line -= 1 end end
# File lib/SVG/Graph/Line.rb, line 256 def get_css return <<EOL /* default line styles */ .line1{ fill: none; stroke: #ff0000; stroke-width: 1px; } .line2{ fill: none; stroke: #0000ff; stroke-width: 1px; } .line3{ fill: none; stroke: #00ff00; stroke-width: 1px; } .line4{ fill: none; stroke: #ffcc00; stroke-width: 1px; } .line5{ fill: none; stroke: #00ccff; stroke-width: 1px; } .line6{ fill: none; stroke: #ff00ff; stroke-width: 1px; } .line7{ fill: none; stroke: #00ffff; stroke-width: 1px; } .line8{ fill: none; stroke: #ffff00; stroke-width: 1px; } .line9{ fill: none; stroke: #ccc6666; stroke-width: 1px; } .line10{ fill: none; stroke: #663399; stroke-width: 1px; } .line11{ fill: none; stroke: #339900; stroke-width: 1px; } .line12{ fill: none; stroke: #9966FF; stroke-width: 1px; } /* default fill styles */ .fill1{ fill: #cc0000; fill-opacity: 0.2; stroke: none; } .fill2{ fill: #0000cc; fill-opacity: 0.2; stroke: none; } .fill3{ fill: #00cc00; fill-opacity: 0.2; stroke: none; } .fill4{ fill: #ffcc00; fill-opacity: 0.2; stroke: none; } .fill5{ fill: #00ccff; fill-opacity: 0.2; stroke: none; } .fill6{ fill: #ff00ff; fill-opacity: 0.2; stroke: none; } .fill7{ fill: #00ffff; fill-opacity: 0.2; stroke: none; } .fill8{ fill: #ffff00; fill-opacity: 0.2; stroke: none; } .fill9{ fill: #cc6666; fill-opacity: 0.2; stroke: none; } .fill10{ fill: #663399; fill-opacity: 0.2; stroke: none; } .fill11{ fill: #339900; fill-opacity: 0.2; stroke: none; } .fill12{ fill: #9966FF; fill-opacity: 0.2; stroke: none; } /* default line styles */ .key1,.dataPoint1{ fill: #ff0000; stroke: none; stroke-width: 1px; } .key2,.dataPoint2{ fill: #0000ff; stroke: none; stroke-width: 1px; } .key3,.dataPoint3{ fill: #00ff00; stroke: none; stroke-width: 1px; } .key4,.dataPoint4{ fill: #ffcc00; stroke: none; stroke-width: 1px; } .key5,.dataPoint5{ fill: #00ccff; stroke: none; stroke-width: 1px; } .key6,.dataPoint6{ fill: #ff00ff; stroke: none; stroke-width: 1px; } .key7,.dataPoint7{ fill: #00ffff; stroke: none; stroke-width: 1px; } .key8,.dataPoint8{ fill: #ffff00; stroke: none; stroke-width: 1px; } .key9,.dataPoint9{ fill: #cc6666; stroke: none; stroke-width: 1px; } .key10,.dataPoint10{ fill: #663399; stroke: none; stroke-width: 1px; } .key11,.dataPoint11{ fill: #339900; stroke: none; stroke-width: 1px; } .key12,.dataPoint12{ fill: #9966FF; stroke: none; stroke-width: 1px; } EOL end
# File lib/SVG/Graph/Line.rb, line 145 def get_x_labels @config[:fields] end
# File lib/SVG/Graph/Line.rb, line 155 def get_y_labels maxvalue = max_value minvalue = min_value range = maxvalue - minvalue top_pad = range == 0 ? 10 : range / 20.0 scale_range = (maxvalue + top_pad) - minvalue scale_division = scale_divisions || (scale_range / 10.0) if scale_integers scale_division = scale_division < 1 ? 1 : scale_division.round end rv = [] maxvalue = maxvalue%scale_division == 0 ? maxvalue : maxvalue + scale_division minvalue.step( maxvalue, scale_division ) {|v| rv << v} return rv end
# File lib/SVG/Graph/Line.rb, line 111 def max_value max = 0 if (stacked == true) then sums = Array.new(@config[:fields].length).fill(0) @data.each do |data| sums.each_index do |i| sums[i] += data[:data][i].to_f end end max = sums.max else max = @data.collect{|x| x[:data].max}.max end return max end
# File lib/SVG/Graph/Line.rb, line 131 def min_value min = 0 if (min_scale_value.nil? == false) then min = min_scale_value elsif (stacked == true) then min = @data[-1][:data].min else min = @data.collect{|x| x[:data].min}.min end return min end