String based "name" for Variable class removed for performance

src/FactorGraphs/KeyedVariable.php

@@ -6,9 +6,9 @@ namespace DNW\Skills\FactorGraphs;
 
 class KeyedVariable extends Variable
 {
-    public function __construct(private readonly mixed $key, string $name, mixed $prior)
+    public function __construct(private readonly mixed $key, mixed $prior)
     {
-        parent::__construct($name, $prior);
+        parent::__construct($prior);
     }
 
     public function getKey(): mixed

src/FactorGraphs/Variable.php

@@ -6,15 +6,12 @@ namespace DNW\Skills\FactorGraphs;
 
 use DNW\Skills\Numerics\GaussianDistribution;
 
-class Variable implements \Stringable
+class Variable
 {
-    private readonly string $name;
-
     private mixed $value;
 
-    public function __construct(string $name, private GaussianDistribution $prior)
+    public function __construct(private GaussianDistribution $prior)
     {
-        $this->name = 'Variable[' . $name . ']';
         $this->resetToPrior();
     }
 
@@ -32,9 +29,4 @@ class Variable implements \Stringable
     {
         $this->value = $this->prior;
     }
-
-    public function __toString(): string
-    {
-        return $this->name;
-    }
 }

src/FactorGraphs/VariableFactory.php

@@ -10,17 +10,17 @@ class VariableFactory
     {
     }
 
-    public function createBasicVariable(string $name): Variable
+    public function createBasicVariable(): Variable
     {
         $initializer = $this->variablePriorInitializer;
 
-        return new Variable($name, $initializer());
+        return new Variable($initializer());
     }
 
-    public function createKeyedVariable(mixed $key, string $name): KeyedVariable
+    public function createKeyedVariable(mixed $key): KeyedVariable
     {
         $initializer = $this->variablePriorInitializer;
 
-        return new KeyedVariable($key, $name, $initializer());
+        return new KeyedVariable($key, $initializer());
     }
 }

src/TrueSkill/Factors/GaussianFactor.php

@@ -31,8 +31,7 @@ abstract class GaussianFactor extends Factor
         return parent::createVariableToMessageBindingWithMessage(
             $variable,
             new Message(
-                $newDistribution,
-                sprintf('message from %s to %s', (string)$this, (string)$variable)
+                $newDistribution,'message from %s to %s'
             )
         );
     }

src/TrueSkill/Factors/GaussianGreaterThanFactor.php

@@ -16,12 +16,9 @@ use DNW\Skills\TrueSkill\TruncatedGaussianCorrectionFunctions;
  */
 class GaussianGreaterThanFactor extends GaussianFactor
 {
-    private readonly float $epsilon;
-
-    public function __construct(float $epsilon, Variable $variable)
+    public function __construct(private readonly float $epsilon, Variable $variable)
     {
-        parent::__construct(\sprintf('%s > %.2f', (string)$variable, $epsilon));
-        $this->epsilon = $epsilon;
+        parent::__construct('%s > %.2f');
         $this->createVariableToMessageBinding($variable);
     }
 

src/TrueSkill/Factors/GaussianLikelihoodFactor.php

@@ -21,7 +21,7 @@ class GaussianLikelihoodFactor extends GaussianFactor
 
     public function __construct(float $betaSquared, Variable $variable1, Variable $variable2)
     {
-        parent::__construct(sprintf('Likelihood of %s going to %s', (string)$variable2, (string)$variable1));
+        parent::__construct('Likelihood of %s going to %s');
         $this->precision = 1.0 / $betaSquared;
         $this->createVariableToMessageBinding($variable1);
         $this->createVariableToMessageBinding($variable2);

src/TrueSkill/Factors/GaussianPriorFactor.php

@@ -19,11 +19,11 @@ class GaussianPriorFactor extends GaussianFactor
 
     public function __construct(float $mean, float $variance, Variable $variable)
     {
-        parent::__construct(sprintf('Prior value going to %s', (string)$variable));
+        parent::__construct('Prior value going to %s');
         $this->newMessage = new GaussianDistribution($mean, sqrt($variance));
         $newMessage = new Message(
             GaussianDistribution::fromPrecisionMean(0, 0),
-            sprintf('message from %s to %s', (string)$this, (string)$variable)
+            'message from %s to %s'
         );
 
         $this->createVariableToMessageBindingWithMessage($variable, $newMessage);

src/TrueSkill/Factors/GaussianWeightedSumFactor.php

@@ -42,7 +42,7 @@ class GaussianWeightedSumFactor extends GaussianFactor
      */
     public function __construct(Variable $sumVariable, array $variablesToSum, array $variableWeights)
     {
-        parent::__construct(self::createName((string)$sumVariable, $variablesToSum, $variableWeights));
+        parent::__construct('$sumVariable, $variablesToSum, $variableWeights');
 
         // The first weights are a straightforward copy
         // v_0 = a_1*v_1 + a_2*v_2 + ... + a_n * v_n
@@ -235,42 +235,4 @@ class GaussianWeightedSumFactor extends GaussianFactor
             $updatedVariables
         );
     }
-
-    /**
-     * @param Variable[] $variablesToSum
-     * @param float[] $weights
-     */
-    private static function createName(string $sumVariable, array $variablesToSum, array $weights): string
-    {
-        // TODO: Perf? Use PHP equivalent of StringBuilder? implode on arrays?
-        $result = $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;
-    }
 }

src/TrueSkill/Factors/GaussianWithinFactor.php

@@ -16,12 +16,9 @@ use DNW\Skills\TrueSkill\TruncatedGaussianCorrectionFunctions;
  */
 class GaussianWithinFactor extends GaussianFactor
 {
-    private readonly float $epsilon;
-
-    public function __construct(float $epsilon, Variable $variable)
+    public function __construct(private readonly float $epsilon, Variable $variable)
     {
-        parent::__construct(sprintf('%s <= %.2f', (string)$variable, $epsilon));
-        $this->epsilon = $epsilon;
+        parent::__construct('%s <= %.2f');
         $this->createVariableToMessageBinding($variable);
     }
 

src/TrueSkill/Layers/PlayerPerformancesToTeamPerformancesLayer.php

@@ -21,7 +21,7 @@ class PlayerPerformancesToTeamPerformancesLayer extends TrueSkillFactorGraphLaye
          */
         foreach ($inputVariablesGroups as $currentTeam) {
             $localCurrentTeam = $currentTeam;
-            $teamPerformance = $this->createOutputVariable($localCurrentTeam);
+            $teamPerformance = $this->createOutputVariable();
             $newSumFactor = $this->createPlayerToTeamSumFactor($localCurrentTeam, $teamPerformance);
 
             $this->addLayerFactor($newSumFactor);
@@ -85,14 +85,10 @@ class PlayerPerformancesToTeamPerformancesLayer extends TrueSkillFactorGraphLaye
     }
 
     /**
-     * @param KeyedVariable[] $team
+     * Team's performance
      */
-    private function createOutputVariable(array $team): Variable
+    private function createOutputVariable(): Variable
     {
-        $memberNames = array_map(static fn($currentPlayer): string => (string)($currentPlayer->getKey()->getId()), $team);
-
-        $teamMemberNames = \implode(', ', $memberNames);
-
-        return $this->getParentFactorGraph()->getVariableFactory()->createBasicVariable('Team[' . $teamMemberNames . "]'s performance");
+        return $this->getParentFactorGraph()->getVariableFactory()->createBasicVariable();
     }
 }

src/TrueSkill/Layers/PlayerPriorValuesToSkillsLayer.php

@@ -77,6 +77,6 @@ class PlayerPriorValuesToSkillsLayer extends TrueSkillFactorGraphLayer
         $parentFactorGraph = $this->getParentFactorGraph();
         $variableFactory = $parentFactorGraph->getVariableFactory();
 
-        return $variableFactory->createKeyedVariable($key, $key->getId() . "'s skill");
+        return $variableFactory->createKeyedVariable($key);
     }
 }

src/TrueSkill/Layers/PlayerSkillsToPerformancesLayer.php

@@ -48,7 +48,7 @@ class PlayerSkillsToPerformancesLayer extends TrueSkillFactorGraphLayer
 
     private function createOutputVariable(mixed $key): KeyedVariable
     {
-        return $this->getParentFactorGraph()->getVariableFactory()->createKeyedVariable($key, $key->getId() . "'s performance");
+        return $this->getParentFactorGraph()->getVariableFactory()->createKeyedVariable($key);
     }
 
     public function createPriorSchedule(): ?ScheduleSequence

src/TrueSkill/Layers/TeamPerformancesToTeamPerformanceDifferencesLayer.php

@@ -40,8 +40,11 @@ class TeamPerformancesToTeamPerformanceDifferencesLayer extends TrueSkillFactorG
         return new GaussianWeightedSumFactor($output, $teams, $weights);
     }
 
+    /**
+     * Team performance difference
+     */
     private function createOutputVariable(): Variable
     {
-        return $this->getParentFactorGraph()->getVariableFactory()->createBasicVariable('Team performance difference');
+        return $this->getParentFactorGraph()->getVariableFactory()->createBasicVariable();
     }
 }

tests/FactorGraphs/VariableTest.php

@@ -13,13 +13,12 @@ class VariableTest extends TestCase
     public function testGetterSetter(): void
     {
         $gd_prior = new GaussianDistribution();
-        $var      = new Variable('dummy', $gd_prior);
+        $var      = new Variable($gd_prior);
         $this->assertEquals($gd_prior, $var->getValue());
 
         $gd_new = new GaussianDistribution();
         $this->assertEquals($gd_new, $var->getValue());
         $var->resetToPrior();
         $this->assertEquals($gd_prior, $var->getValue());
-        $this->assertEquals('Variable[dummy]', (string)$var);
     }
 }