correlations on the admins page

app/controllers/admins_controller.rb

@@ -66,7 +66,7 @@ class AdminsController < ApplicationController
   end
 
   def correlations
-    @post_count_correlation = Statistics.new.post_count_correlation
+    @correlations_hash = Statistics.new.generate_correlations
   end
 
   private

app/views/admins/correlations.haml

@@ -6,6 +6,8 @@
 
 .span-24.last
   %h1
-    = "Correlation between Post Count and Sign In Count"
+    = "Correlations between with Sign In Count"
   %ul
-    = @post_count_correlation
+    - @correlations_hash.keys.each do |k|
+      %li
+        = "#{k.to_s}, #{@correlations_hash[k]}"

lib/statistics.rb

@@ -55,16 +55,16 @@ SQL
 SQL
   end
 
-  def post_count_correlation
+  def correlate(first_metric, second_metric)
 
     # [{"id" => 1 , "count" => 123}]
 
     x_array = []
     y_array = []
 
-    post_count_hash.keys.each do |k| 
-      if val = sign_in_count_hash[k]
-        x_array << post_count_hash[k]
+    self.result_hash(first_metric).keys.each do |k| 
+      if val = self.result_hash(second_metric)[k]
+        x_array << self.result_hash(first_metric)[k]
         y_array << val
       end
     end
@@ -72,15 +72,15 @@ SQL
     correlation(x_array, y_array)
   end
 
+  def generate_correlations
+    result = {}
+    [:posts_count, :invites_sent_count, :tags_followed_count,
+     :mentions_count].each do |metric|
+      result[metric] = self.correlate(metric,:sign_in_count)
+     end
+    result
+  end
   
-  ###\
-  #def correlate(thing)
-  #  sql = self.send("#{thing}_count_sql".to_sym)
-  #  self.correlation(User.connection.select_all(sql), 
-  #end
-
-
-  ###
 
   def correlation(x_array, y_array)
     x = x_array.to_scale
@@ -99,23 +99,17 @@ SQL
     User.where("username IS NOT NULL").where("created_at > ? and created_at < ?", Time.now - (n+1).weeks, Time.now - n.weeks)
   end
 
-  def post_count_hash
-    unless @post_count_hash
-      post_count_array = User.connection.select_all(self.posts_count_sql)
+  #@param [Symbol] input type
+  #@returns [Hash] of resulting query
+  def result_hash(type)
+    instance_hash = self.instance_variable_get("@#{type.to_s}_hash".to_sym)
+    unless instance_hash
+      post_count_array = User.connection.select_all(self.send("#{type.to_s}_sql".to_sym))
 
-      @post_count_hash = {}
-      post_count_array.each{ |h| @post_count_hash[h['id']] = h["count"]}
+      instance_hash = {}
+      post_count_array.each{ |h| instance_hash[h['id']] = h["count"]}
+      self.instance_variable_set("@#{type.to_s}_hash".to_sym, instance_hash)
     end
-    @post_count_hash
-  end
-
-  def sign_in_count_hash
-    unless @sign_in_count_hash
-      sign_in_count_array = User.connection.select_all(self.sign_in_count_sql)
-
-      @sign_in_count_hash = {}
-      sign_in_count_array.each{ |h| @sign_in_count_hash[h['id']] = h["count"]}
-    end
-    @sign_in_count_hash
+    instance_hash
   end
 end

spec/lib/statistics_spec.rb

@@ -57,22 +57,25 @@ describe Statistics do
       @stats.correlation([1,2,1,2],[1,1,2,2]).to_s.should == 0.0.to_s
     end
   end
-  describe "#correlation_hash" do
+  describe "#generate_correlations" do
 
     it 'it returns a hash of including start and end time' do
+      pending
       hash = @stats.correlation_hash
-      hash[:starrt_time].should == @time
+      hash[:start_time].should == @time
       hash[:end_time].should == @time - 1.week
     end
 
     it 'returns the post count (and sign_in_count) correlation' do
-      @stats.stub(:posts_count_correlation).and_return(0.5)
+      bob.sign_in_count = 1
+      bob.post(:status_message, :text => "here is a message")
+      bob.save!
 
-      @stats.generate_correlations[:posts_count].should == 0.5
+      @stats.generate_correlations[:posts_count].to_s.should == "1.0"
     end
   end
   
-  describe "#post_count_correlation" do
+  describe "#correlate" do
     it 'calls correlation with post' do
       User.connection.should_receive(:select_all).and_return([{"id"=> 1, "count" => 7},
                                                             {"id" => 2, "count" => 8},
@@ -82,7 +85,7 @@ describe Statistics do
                                                             )
 
       @stats.should_receive(:correlation).with([7,9],[17,19]).and_return(0.5)
-      @stats.posts_count_correlation.should == 0.5
+      @stats.correlate(:posts_count,:sign_in_count).should == 0.5
     end
   end