obsolete.ChilliProject/lib/SVG/Graph/Bar.rb

150 lines
4.1 KiB
Ruby
Raw Normal View History

2011-10-29 16:19:11 +04:00
#-- encoding: UTF-8
2011-05-29 23:00:18 +04:00
require 'rexml/document'
require 'SVG/Graph/Graph'
require 'SVG/Graph/BarBase'
module SVG
module Graph
# === Create presentation quality SVG bar graphs easily
#
# = Synopsis
#
# require 'SVG/Graph/Bar'
#
# fields = %w(Jan Feb Mar);
# data_sales_02 = [12, 45, 21]
#
# graph = SVG::Graph::Bar.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[http://www.w3c.org/tr/svg bar 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.
#
# = Notes
#
# The default stylesheet handles upto 12 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 12 data sets as they will have no style and
# be in black.
#
# = Examples
#
# * http://germane-software.com/repositories/public/SVG/test/test.rb
#
# = See also
#
# * SVG::Graph::Graph
# * SVG::Graph::BarHorizontal
# * SVG::Graph::Line
# * SVG::Graph::Pie
# * SVG::Graph::Plot
# * SVG::Graph::TimeSeries
class Bar < BarBase
include REXML
# See Graph::initialize and BarBase::set_defaults
def set_defaults
super
self.top_align = self.top_font = 1
end
protected
def get_x_labels
@config[:fields]
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 x_label_offset( width )
width / 2.0
end
def draw_data
minvalue = min_value
fieldwidth = field_width
unit_size = (@graph_height.to_f - font_size*2*top_font) /
(get_y_labels.max - get_y_labels.min)
bargap = bar_gap ? (fieldwidth < 10 ? fieldwidth / 2 : 10) : 0
bar_width = fieldwidth - bargap
bar_width /= @data.length if stack == :side
x_mod = (@graph_width-bargap)/2 - (stack==:side ? bar_width/2 : 0)
bottom = @graph_height
field_count = 0
@config[:fields].each_index { |i|
dataset_count = 0
for dataset in @data
# cases (assume 0 = +ve):
# value min length
# +ve +ve value - min
# +ve -ve value - 0
# -ve -ve value.abs - 0
value = dataset[:data][i]
left = (fieldwidth * field_count)
length = (value.abs - (minvalue > 0 ? minvalue : 0)) * unit_size
# top is 0 if value is negative
top = bottom - (((value < 0 ? 0 : value) - minvalue) * unit_size)
left += bar_width * dataset_count if stack == :side
@graph.add_element( "rect", {
"x" => left.to_s,
"y" => top.to_s,
"width" => bar_width.to_s,
"height" => length.to_s,
"class" => "fill#{dataset_count+1}"
})
make_datapoint_text(left + bar_width/2.0, top - 6, value.to_s)
dataset_count += 1
end
field_count += 1
}
end
end
end
end