@@ -50,6 +50,9 @@ user = User.find(:first) user.similar_users #=> [...] user.recommended_books #=> [...] +book = Book.find(:first) +book.similar_books #=> [...] + Example 2 ========= @@ -110,6 +113,7 @@ user.recommended_books #=> [...] # # The advantage of using a dataset is that you don't need to load all the users & items into # memory (which you do normally). The disadvantage is that you won't get as accurate results. +# Contact ======= README @@ -36,9 +36,15 @@ module MadeByMany class_inheritable_accessor :aar_options self.aar_options = options + + options[:on_class].class_eval do + define_method "similar_#{options[:on]}" do + Logic.similar_items(self, options) + end + end define_method "similar_#{options[:class].name.underscore.pluralize}" do - Logic.similar(self, options) + Logic.similar_users(self, options) end define_method "recommended_#{options[:on_class].name.underscore.pluralize}" do @@ -67,7 +73,7 @@ module MadeByMany }.compact.inject({}) {|h, item| h[item.id] = item; h } end end - + end end @@ -144,7 +150,7 @@ module MadeByMany num / den end - def self.similar(user, options) + def self.similar_users(user, options) rankings = [] items, prefs = self.matrix(options) prefs.each do |u, _| @@ -169,6 +175,43 @@ module MadeByMany user } end + + def self.similar_items(item, options) + if options[:use_dataset] + if options[:split_dataset] + rankings = Rails.cache.read("aar_#{options[:on]}_#{item.id}") + else + cached_dataset = Rails.cache.read("aar_#{options[:on]}_dataset") + logger.warn 'ActsRecommendable has an empty dataset - rebuild it' unless cached_dataset + rankings = cached_dataset && cached_dataset[self.id] + end + else + users, prefs = self.inverted_matrix(options) + rankings = [] + prefs.each do |i, _| + next if i == item.id + rankings << [self.__send__(options[:algorithm], prefs, users, item.id, i), i] + end + end + return [] unless rankings + + rankings = rankings.select {|score, _| score > 0.0 } + rankings = rankings.sort_by {|score, _| score }.reverse + rankings = rankings[0..(options[:limit] - 1)] + + # Return the sorted list + ranking_ids = rankings.collect {|_, u| u } + ar_items = options[:on_class].find_some_without_failing(ranking_ids) + ar_items = ar_items.inject({}){ |h, item| h[item.id] = item; h } + + rankings.collect {|score, item_id| + item = ar_items[item_id] + def item.similar_score; return @similar_score; end + def item.similar_score=(d); @similar_score = d; end + item.similar_score = score + item + } + end def self.recommended(user, options) totals = {} lib/acts_as_recommendable.rb e927612651e89cd298307fa666830abd06852353 Alex MacCaw maccman@gmail.com http://github.com/maccman/acts_as_recommendable/commit/f30d171e2ec2194d18502f3e7f51b43b3f3200b8 f30d171e2ec2194d18502f3e7f51b43b3f3200b8 2008-09-11T07:46:36-07:00 2008-09-11T07:46:36-07:00 Add Book#similar_books eb3d37a8c2433e6e0362cf629ff5c1d7e0b553a7 Alex MacCaw maccman@gmail.com