Fix a bug where predictions are always 0.0

Signed-off-by: David Celis <david@davidcelis.com>
davidcelis · Oct 24, 2012 · c8efb83 · c8efb83
1 parent b7202f4
commit c8efb83
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Showing 2 changed files with 7 additions and 6 deletions.
diff --git a/lib/recommendable/helpers/calculations.rb b/lib/recommendable/helpers/calculations.rb
@@ -131,11 +131,12 @@ def predict_for(user_id, klass, item_id)
           disliked_by_set = Recommendable::Helpers::RedisKeyMapper.disliked_by_set_for(klass, item_id)
           similarity_sum = 0.0
 
-          Recommendable.redis.smembers(liked_by_set).inject(similarity_sum) do |sum, id|
-            sum += Recommendable.redis.zscore(similarity_set, id).to_f
+          similarity_sum += Recommendable.redis.smembers(liked_by_set).inject(0) do |memo, id|
+            memo += Recommendable.redis.zscore(similarity_set, id).to_f
           end
-          Recommendable.redis.smembers(disliked_by_set).inject(similarity_sum) do |sum, id|
-            sum -= Recommendable.redis.zscore(similarity_set, id).to_f
+
+          similarity_sum += Recommendable.redis.smembers(disliked_by_set).inject(0) do |memo, id|
+            memo -= Recommendable.redis.zscore(similarity_set, id).to_f
           end
 
           liked_by_count = Recommendable.redis.scard(liked_by_set)

diff --git a/lib/recommendable/version.rb b/lib/recommendable/version.rb
@@ -1,8 +1,8 @@
 module Recommendable
   MAJOR = 2
   MINOR = 0
-  PATCH = 0
-  PRE   = 20121011
+  PATCH = 1
+  PRE   = nil
 
   VERSION = [MAJOR, MINOR, PATCH, PRE].compact.join '.'
 end