lib/conductor.rb in conductor-0.6.5 vs lib/conductor.rb in conductor-0.7.0

@@ -13,11 +13,12 @@
   MAX_WEIGHTING_FACTOR = 1.25
   MINIMUM_LAUNCH_DAYS = 7
   DBG = false
 
   cattr_writer :cache
-
+  cattr_writer :days_till_weighting
+  
   def self.cache
     @@cache || Rails.cache
   end
 
   class << self
@@ -26,23 +27,49 @@
     end
 
     def identity
       return (@conductor_identity || ActiveSupport::SecureRandom.hex(16))
     end
+    
+    def minimum_launch_days
+      return (@@days_till_weighting || MINIMUM_LAUNCH_DAYS)
+    end
+    
+    def attribute_for_weighting=(value)
+      raise "Conductor.attribute_for_weighting must be either :views, :conversions or :conversion_value (default)" unless [:views, :conversions, :conversion_value].include?(value) 
+      @attribute_for_weighting = value
+    end
+    
+    def attribute_for_weighting
+      return (@attribute_for_weighting || :conversion_value)
+    end
 
     def log(msg)
       puts msg if DBG
     end
-    
+
     def sanitize(str)
       str.gsub(/\s/,'_').downcase
     end
   end
-  
+
 end
 
 
 class Array
   def sum_it(attribute)
     self.map {|x| x.send(attribute) }.compact.sum
+  end
+
+  def weighted_mean_of_attribute(attribute)
+    self.map {|x| x.send(attribute) }.compact.weighted_mean
+  end
+
+  def weighted_mean
+    w_sum = sum(self)
+    return 0.00 if w_sum == 0.00
+    
+    w_prod = 0
+    self.each_index {|i| w_prod += (i+1) * self[i].to_f}
+    w_prod.to_f / w_sum.to_f
   end
 end