From 5cb1919c2180125115cf048821cbbe36e595796a Mon Sep 17 00:00:00 2001
From: Jeff Moser <jeff@moserware.com>
Date: Sun, 26 Sep 2010 21:43:17 -0400
Subject: [PATCH] Start of journey to actually give real names to factor graph
 variables using more PHP style

---
 PHPSkills/FactorGraphs/VariableFactory.php    |  8 ++--
 PHPSkills/Player.php                          |  2 +-
 .../Factors/GaussianWeightedSumFactor.php     | 39 ++++++++++++++++++-
 ...yerPerformancesToTeamPerformancesLayer.php | 13 +++++--
 .../Layers/PlayerPriorValuesToSkillsLayer.php |  2 +-
 .../PlayerSkillsToPerformancesLayer.php       |  2 +-
 6 files changed, 53 insertions(+), 13 deletions(-)

diff --git a/PHPSkills/FactorGraphs/VariableFactory.php b/PHPSkills/FactorGraphs/VariableFactory.php
index 74cb315..3d72f8e 100644
--- a/PHPSkills/FactorGraphs/VariableFactory.php
+++ b/PHPSkills/FactorGraphs/VariableFactory.php
@@ -14,17 +14,17 @@ class VariableFactory
         $this->_variablePriorInitializer = &$variablePriorInitializer;
     }
 
-    public function createBasicVariable()
+    public function createBasicVariable($name)
     {
         $initializer = $this->_variablePriorInitializer;
-        $newVar = new Variable("variable", $initializer());
+        $newVar = new Variable($name, $initializer());
         return $newVar;
     }
 
-    public function createKeyedVariable($key)
+    public function createKeyedVariable($key, $name)
     {
         $initializer = $this->_variablePriorInitializer;
-        $newVar = new KeyedVariable($key, "key variable", $initializer());
+        $newVar = new KeyedVariable($key, $name, $initializer());
         return $newVar;
     }
 }
diff --git a/PHPSkills/Player.php b/PHPSkills/Player.php
index 2d44e74..9819101 100644
--- a/PHPSkills/Player.php
+++ b/PHPSkills/Player.php
@@ -71,7 +71,7 @@ class Player implements ISupportPartialPlay, ISupportPartialUpdate
     {
         if ($this->_Id != null)
         {
-            return $this->_Id;
+            return (string)$this->_Id;
         }
 
         return parent::__toString();
diff --git a/PHPSkills/TrueSkill/Factors/GaussianWeightedSumFactor.php b/PHPSkills/TrueSkill/Factors/GaussianWeightedSumFactor.php
index 61f789f..3e221f5 100644
--- a/PHPSkills/TrueSkill/Factors/GaussianWeightedSumFactor.php
+++ b/PHPSkills/TrueSkill/Factors/GaussianWeightedSumFactor.php
@@ -227,9 +227,44 @@ class GaussianWeightedSumFactor extends GaussianFactor
                                    $updatedVariables);
     }
 
-    private static function createName($sumVariable, $variablesToSum, $variableWeights)
+    private static function createName($sumVariable, $variablesToSum, $weights)
     {
-        return "TODO";
+        // TODO: Perf? Use PHP equivalent of StringBuilder? implode on arrays?
+        $result = (string)$sumVariable;
+        $result .= ' = ';
+        
+        $totalVars = count($variablesToSum);
+        for($i = 0; $i < $totalVars; $i++)
+        {
+            $isFirst = ($i == 0);
+            
+            if($isFirst && ($weights[$i] < 0))
+            {
+                $result .= '-';
+            }
+
+            $absValue = sprintf("%.2f", \abs($weights[$i])); // 0.00?
+            $result .= $absValue;
+            $result .= "*[";
+            $result .= (string)$variablesToSum[$i];
+            $result .= ']';
+            
+            $isLast = ($i == ($totalVars - 1));
+            
+            if(!$isLast)
+            {
+                if($weights[$i + 1] >= 0)
+                {
+                    $result .= ' + ';
+                }
+                else
+                {
+                    $result .= ' - ';
+                }
+            }                
+        }
+        
+        return $result;
     }
 }
 
diff --git a/PHPSkills/TrueSkill/Layers/PlayerPerformancesToTeamPerformancesLayer.php b/PHPSkills/TrueSkill/Layers/PlayerPerformancesToTeamPerformancesLayer.php
index 7803a03..f31dbbd 100644
--- a/PHPSkills/TrueSkill/Layers/PlayerPerformancesToTeamPerformancesLayer.php
+++ b/PHPSkills/TrueSkill/Layers/PlayerPerformancesToTeamPerformancesLayer.php
@@ -27,7 +27,7 @@ class PlayerPerformancesToTeamPerformancesLayer extends TrueSkillFactorGraphLaye
     {
         foreach ($this->getInputVariablesGroups() as $currentTeam)
         {
-            $teamPerformance = &$this->createOutputVariable($currentTeam);
+            $teamPerformance = $this->createOutputVariable($currentTeam);
             $newSumFactor = $this->createPlayerToTeamSumFactor($currentTeam, $teamPerformance);
             $this->addLayerFactor($newSumFactor);
 
@@ -83,9 +83,14 @@ class PlayerPerformancesToTeamPerformancesLayer extends TrueSkillFactorGraphLaye
 
     private function createOutputVariable(&$team)
     {
-        ///$teamMemberNames = String.Join(", ", team.Select(teamMember => teamMember.Key.ToString()).ToArray());
-        $teamMemberNames = "TODO";
-        return $this->getParentFactorGraph()->getVariableFactory()->createBasicVariable("Team[{0}]'s performance", $teamMemberNames);
+        $memberNames = \array_map(function ($currentPlayer)
+                                  {
+                                        return (string)($currentPlayer->getKey());
+                                  },
+                                  $team);
+
+        $teamMemberNames = \join(", ", $memberNames);
+        return $this->getParentFactorGraph()->getVariableFactory()->createBasicVariable("Team[" . $teamMemberNames . "]'s performance");
     }
 }
 
diff --git a/PHPSkills/TrueSkill/Layers/PlayerPriorValuesToSkillsLayer.php b/PHPSkills/TrueSkill/Layers/PlayerPriorValuesToSkillsLayer.php
index ef4db9c..1e0843a 100644
--- a/PHPSkills/TrueSkill/Layers/PlayerPriorValuesToSkillsLayer.php
+++ b/PHPSkills/TrueSkill/Layers/PlayerPriorValuesToSkillsLayer.php
@@ -69,7 +69,7 @@ class PlayerPriorValuesToSkillsLayer extends TrueSkillFactorGraphLayer
     {
         $parentFactorGraph = $this->getParentFactorGraph();
         $variableFactory = $parentFactorGraph->getVariableFactory();
-        return $variableFactory->createKeyedVariable($key, "{0}'s skill", $key);
+        return $variableFactory->createKeyedVariable($key, $key . "'s skill");
     }
 }
 
diff --git a/PHPSkills/TrueSkill/Layers/PlayerSkillsToPerformancesLayer.php b/PHPSkills/TrueSkill/Layers/PlayerSkillsToPerformancesLayer.php
index f9f8b45..65dd08e 100644
--- a/PHPSkills/TrueSkill/Layers/PlayerSkillsToPerformancesLayer.php
+++ b/PHPSkills/TrueSkill/Layers/PlayerSkillsToPerformancesLayer.php
@@ -44,7 +44,7 @@ class PlayerSkillsToPerformancesLayer extends TrueSkillFactorGraphLayer
 
     private function createOutputVariable(&$key)
     {
-        return $this->getParentFactorGraph()->getVariableFactory()->createKeyedVariable($key, "{0}'s performance", $key);
+        return $this->getParentFactorGraph()->getVariableFactory()->createKeyedVariable($key, $key . "'s performance");
     }
 
     public function createPriorSchedule()