added readme, some doc and cleaned up gem- and rakefile

.gitignore

@@ -1,21 +1,5 @@
-## MAC OS
 .DS_Store
-
-## TEXTMATE
-*.tmproj
-tmtags
-
-## EMACS
-*~
-\#*
-.\#*
-
-## VIM
-*.swp
-
-## PROJECT::GENERAL
 coverage
-rdoc
-pkg
-
-## PROJECT::SPECIFIC
+doc
+.yardoc
+*.gem

Gemfile

@@ -0,0 +1,8 @@
+source :gemcutter
+
+gem 'rake',       '>= 0.8.7'
+gem 'rspec',      '>= 1.3.0'
+gem 'rcov',       '>= 0.9.8'
+gem 'yard',       '>= 0.5.4'
+gem 'yard-rspec', '>= 0.1.0'
+gem 'bluecloth',  '>= 2.0.5'

HISTORY.md

@@ -0,0 +1,4 @@
+v0.1.0
+------
+
+* Initial release of the trueskill gem

LICENSE

@@ -1,4 +1,4 @@
-Copyright (c) 2009 Lars Kuhnt
+Copyright (c) 2010 Lars Kuhnt
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the

README.md

@@ -0,0 +1,66 @@
+trueskill
+=========
+
+trueskill is a rating-system for games with an arbitrary number of teams and players developed by Microsoft Research. It is based on the Glicko rating system and solves some major flaws of the ELO system.
+
+Usage
+-----
+
+Example:
+
+    require 'rubygems'
+    require 'saulabs/trueskill'
+
+    include Saulabs::TrueSkill
+
+    # team 1 has just one player with a mean skill of 27.1, a skill-deviation of 2.13
+    # and an play activity of 100 %
+    team1 = [Rating.new(27.1, 2.13, 1.0)]
+
+    # team 2 has two players
+    team2 = [Rating.new(22.0, 0.98, 0.8), Rating.new(31.1, 5.33, 0.9)]
+
+    # team 1 finished first and team 2 second
+    graph = FactorGraph.new([team1, team2], [1,2])
+
+    # update the Ratings
+    graph.update_skills
+
+Installation
+------------
+
+To install the TrueSkill gem, simply run
+
+    [sudo] gem install trueskill
+
+Add the following to your script:
+
+    require 'saulabs/trueskill'
+
+Known issues
+------------
+
+* The calculation of the ranking probability is not yet implemented
+
+Plans
+-----
+
+* 
+
+Note on Patches/Pull Requests
+-----------------------------
+
+* Fork the project.
+* Make your feature addition or bug fix.
+* Add tests for it. This is important so I don't break it in a
+  future version unintentionally.
+* Commit, do not mess with rakefile, version, or history.
+  (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)
+* Send me a pull request. Bonus points for topic branches.
+
+Copyright
+---------
+
+© 2010 Lars Kuhnt (<http://saulabs.net>). 
+
+See LICENSE for details.

Rakefile

@@ -1,46 +1,24 @@
 require 'rubygems'
 require 'rake'
+require 'bundler'
 
-begin
-  require 'jeweler'
-  Jeweler::Tasks.new do |gem|
-    gem.name = "trueskill"
-    gem.summary = %Q{A ruby library for the trueskill rating system}
-    gem.description = %Q{A ruby library for the trueskill rating system}
-    gem.email = "lars.kuhnt@gmail.com"
-    gem.homepage = "http://github.com/saulabs/trueskill"
-    gem.authors = ["Lars Kuhnt"]
-    gem.add_development_dependency "rspec", ">= 1.2.9"
-    gem.add_dependency('narray', '>= 0.5.9.7')
-    # gem is a Gem::Specification... see http://www.rubygems.org/read/chapter/20 for additional settings
-  end
-  Jeweler::GemcutterTasks.new
-rescue LoadError
-  puts "Jeweler (or a dependency) not available. Install it with: gem install jeweler"
-end
+Bundler.setup
+Bundler.require
 
 require 'spec/rake/spectask'
-Spec::Rake::SpecTask.new(:spec) do |spec|
-  spec.libs << 'lib' << 'spec'
-  spec.spec_files = FileList['spec/**/*_spec.rb']
-end
-
-Spec::Rake::SpecTask.new(:rcov) do |spec|
-  spec.libs << 'lib' << 'spec'
-  spec.pattern = 'spec/**/*_spec.rb'
-  spec.rcov = true
-end
-
-task :spec => :check_dependencies
 
+desc 'Default: run specs.'
 task :default => :spec
 
-require 'rake/rdoctask'
-Rake::RDocTask.new do |rdoc|
-  version = File.exist?('VERSION') ? File.read('VERSION') : ""
+desc 'Run the specs'
+Spec::Rake::SpecTask.new(:spec) do |t|
+  t.rcov_opts  << '--exclude "gems/*,spec/*"'
+  t.rcov       = true
+  t.rcov_dir   = 'doc/coverage'
+  t.spec_files = FileList['spec/**/*_spec.rb']
+end
 
-  rdoc.rdoc_dir = 'rdoc'
-  rdoc.title = "trueskill #{version}"
-  rdoc.rdoc_files.include('README*')
-  rdoc.rdoc_files.include('lib/**/*.rb')
+YARD::Rake::YardocTask.new(:doc) do |t|
+  t.files   = ['lib/**/*.rb', 'HISTORY.md']
+  t.options = ['--no-private', '--title', 'trueskill Documentation', '--readme', 'README.md']
 end

lib/saulabs/gauss/distribution.rb

@@ -1,10 +1,13 @@
 module Saulabs
   module Gauss
+
+    # Implementation of a gaussian distribution
+    # 
     class Distribution
 
-      SQRT2 = Math.sqrt(2).freeze
-      INV_SQRT_2PI = (1 / Math.sqrt(2 * Math::PI)).freeze
-      LOG_SQRT_2PI = Math.log(Math.sqrt(2 * Math::PI)).freeze
+      @@sqrt2 = Math.sqrt(2).freeze
+      @@inv_sqrt_2pi = (1 / Math.sqrt(2 * Math::PI)).freeze
+      @@log_sqrt_2pi = Math.log(Math.sqrt(2 * Math::PI)).freeze
 
       # gaussian normal distribution values
       attr_accessor :mean, :deviation, :variance, :precision, :precision_mean
@@ -22,8 +25,7 @@ def initialize(mean = 0.0, deviation = 0.0)
       class << self
 
         def standard
-          @@standard ||= Distribution.new(0.0, 1.0)
-          @@standard
+          Distribution.new(0.0, 1.0)
         end
 
         def with_deviation(mean, deviation)
@@ -46,40 +48,40 @@ def log_product_normalization(x, y)
           return 0.0 if x.precision == 0.0 || y.precision == 0.0
           variance_sum = x.variance + y.variance
           mean_diff = x.mean - y.mean
-          -LOG_SQRT_2PI - (Math.log(variance_sum) / 2.0) - (mean_diff**2 / (2.0 * variance_sum))
+          -@@log_sqrt_2pi - (Math.log(variance_sum) / 2.0) - (mean_diff**2 / (2.0 * variance_sum))
         end
 
         def log_ratio_normalization(x, y)
           return 0.0 if x.precision == 0.0 || y.precision == 0.0
           variance_diff = y.variance - x.variance
           return 0.0 if variance_diff == 0.0
           mean_diff = x.mean - y.mean
-          Math.log(y.variance) + LOG_SQRT_2PI - (Math.log(variance_diff) / 2.0) + (mean_diff**2 / (2.0 * variance_diff))
+          Math.log(y.variance) + @@log_sqrt_2pi - (Math.log(variance_diff) / 2.0) + (mean_diff**2 / (2.0 * variance_diff))
         end
 
         # Computes the cummulative Gaussian distribution at a specified point of interest
         def cumulative_distribution_function(x)
-          0.5 * (1 + Math.erf(x / SQRT2))
+          0.5 * (1 + Math.erf(x / @@sqrt2))
         end
         alias_method :cdf, :cumulative_distribution_function
 
         # Computes the Gaussian density at a specified point of interest
         def probability_density_function(x)
-          INV_SQRT_2PI * Math.exp(-0.5 * (x**2))
+          @@inv_sqrt_2pi * Math.exp(-0.5 * (x**2))
         end
         alias_method :pdf, :probability_density_function
 
         # The inverse of the cummulative Gaussian distribution function
         def quantile_function(x)
-          -SQRT2 * Math.erfc(2.0 * x)
+          -@@sqrt2 * Math.erfc(2.0 * x)
         end
         alias_method :inv_cdf, :quantile_function
 
       end
 
       def value_at(x)
         exp = -(x - @mean)**2.0 / (2.0 * @variance)
-        (1.0/@deviation) * INV_SQRT_2PI * Math.exp(exp)
+        (1.0/@deviation) * @@inv_sqrt_2pi * Math.exp(exp)
       end
 
       # copy values from other distribution

lib/saulabs/trueskill/factor_graph.rb

@@ -5,7 +5,7 @@ class FactorGraph
 
       attr_reader :teams, :beta, :beta_squared, :draw_probability, :epsilon, :layers
 
-      # teams: 2 dimensional array of ratings
+      # @param teams (Array) 2 dimensional array of ratings
       def initialize(teams, ranks, options = {})
         @teams = teams
         @ranks = ranks

spec/saulabs/trueskill_spec.rb

@@ -0,0 +1,7 @@
+require File.dirname(__FILE__) + '/../../spec_helper'
+
+describe Saulabs::TrueSkill do
+
+
+
+end

spec/spec.opts

@@ -1 +1,4 @@
 --color
+--format specdoc
+--loadby mtime
+--reverse