require 'SVG/Graph/Graph' module SVG module Graph # === 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 # # http://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 # # * SVG::Graph::Graph # * SVG::Graph::BarHorizontal # * SVG::Graph::Bar # * SVG::Graph::Pie # * SVG::Graph::Plot # * SVG::Graph::TimeSeries # # == Author # # Sean E. Russell # # Copyright 2004 Sean E. Russell # This software is available under the Ruby license[LICENSE.txt] # class Line < SVG::Graph::Graph # Show a small circle on the graph where the line # goes from one point to the next. attr_accessor :show_data_points # 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. attr_accessor :stacked # Fill in the area under the plot if true attr_accessor :area_fill # 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. 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 # In addition to the defaults set in Graph::initialize, sets # [show_data_points] true # [show_data_values] true # [stacked] false # [area_fill] false 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 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 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 def get_x_labels @config[:fields] end 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 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 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 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 def get_css return <