Package update and implemented new fixes for Rector findings

.phplint.yml

@@ -9,5 +9,4 @@ exclude:
   - vendor
 warning: true
 memory-limit: -1
-no-cache: true
 log-junit: "output/lint.xml"

.woodpecker.yml

@@ -1,15 +1,17 @@
-pipeline:
+when:
-  requirements:
+  - event: [push, tag]
+steps:
+  - name: requirements
     image: composer
     commands:
     - composer install --no-dev
-  run:
+  - name: run
     image: php:cli-bookworm
     commands:
       - php examples/3teams.php
       - php examples/basic.php
-  dependencies:
+  - name: test
     image: composer
     commands:
     - composer install
-    - vendor/bin/phpunit tests
+    - vendor/bin/phpunit tests --no-coverage

benchmark/BasicBench.php

@@ -10,8 +10,10 @@ use DNW\Skills\TrueSkill\FactorGraphTrueSkillCalculator;
 use DNW\Skills\GameInfo;
 use DNW\Skills\Player;
 use DNW\Skills\Team;
-use DNW\Skills\Teams;
 
+/**
+ * Basic Benchmarks.
+ */
 class BasicBench
 {
     /**
@@ -31,7 +33,7 @@ class BasicBench
         $team2 = new Team($p2, $gameInfo->getDefaultRating());
 
         for ($i = 0; $i < 10; ++$i) {
-            $teams = Teams::concat($team1, $team2);
+            $teams = [$team1, $team2];
 
             $calculator = new TwoPlayerTrueSkillCalculator();
 
@@ -62,7 +64,7 @@ class BasicBench
         $team2 = new Team($p2, $gameInfo->getDefaultRating());
 
         for ($i = 0; $i < 10; ++$i) {
-            $teams = Teams::concat($team1, $team2);
+            $teams = [$team1, $team2];
 
             $calculator = new TwoTeamTrueSkillCalculator();
 
@@ -93,7 +95,7 @@ class BasicBench
         $team2 = new Team($p2, $gameInfo->getDefaultRating());
 
         for ($i = 0; $i < 10; ++$i) {
-            $teams = Teams::concat($team1, $team2);
+            $teams = [$team1, $team2];
 
             $calculator = new FactorGraphTrueSkillCalculator();
 
@@ -126,7 +128,7 @@ class BasicBench
         $team3 = new Team($p3, $gameInfo->getDefaultRating());
         
         for ($i = 0; $i < 10; ++$i) {
-            $teams = Teams::concat($team1, $team2, $team3);
+            $teams = [$team1, $team2, $team3];
 
             $calculator = new FactorGraphTrueSkillCalculator();
 

composer.json

@@ -7,11 +7,12 @@
   },
   "require-dev": {
     "phpstan/phpstan": "^1.0",
-    "vimeo/psalm": "^5.21.1",
+    "vimeo/psalm": "dev-master",
     "phpmetrics/phpmetrics": "^3.0-dev",
-    "phpunit/phpunit": "^10.5",
+    "phpunit/phpunit": "^11.2",
     "psalm/plugin-phpunit": "^0.18.4",
-    "rector/rector": "^1.0"
+    "rector/rector": "^1.0",
+    "league/csv": "^9.0"
   },
   "autoload": {
     "psr-4": {
@@ -25,20 +26,22 @@
   },
   "scripts": {
     "test":          "phpunit",
-    "document":      "phpDocumentor", 
+    "document":      "phpDocumentor",
     "benchmark":     "phpbench run --report=default --output=build-artifact",
-    "metrics":       "vendor/bin/phpmetrics --config=phpmetrics.json",
+    "metrics":       "vendor/bin/phpmetrics --config=phpmetrics.yml",
     "lint": [
         "phplint",
-        "phpcs"
+        "phpcs",
+        "phpcbf  src/ tests/ benchmark/ examples/",
+        "phpmd src/,tests/,benchmark/,examples/ text phpmd.ruleset.xml"
     ],
-    "static": [
+    "analyze": [
         "@analyze-phpstan",
         "@analyze-psalm",
         "@analyze-rector"
     ],
     "analyze-phpstan":"vendor/bin/phpstan analyze --error-format=raw",
-    "analyze-psalm":  "vendor/bin/psalm --no-cache",
+    "analyze-psalm":  "vendor/bin/psalm --no-cache --show-info=true",
     "analyze-rector": "vendor/bin/rector --dry-run",
     "html": [
       "pandoc -s README.md -o output/README.html",
@@ -46,10 +49,10 @@
     ],
     "all": [
       "@test",
-      "@document",
-      "@benchmark",
       "@lint",
-      "@static",
+      "@analyze",
+      "@document",
+      "@metrics",
       "@html"
     ]
   }

docs/index.rst

@@ -30,9 +30,9 @@ Links
 * `Project README <README.html>`_
 * `API Documentations <docs/>`_
 * `CodeCoverage <coverage/>`_
-* `Metrics <metrics/>`_
 * `Test report <test/index.html>`_
-* `Mutation testing <mutation/>`_
+* `Mutation testing <mutation/infection.html>`_
+* `Code metrics <metrics/index.html>`_
 
 
 Standard Tools
@@ -47,6 +47,7 @@ PHP Tools
 ---------
 For development Composer and the following packages are used (Recommended as Phars installed via Phive)
 
-* sudo phive install -g composer phpdocumentor infection phpcs phpcbf phploc phpbench overtrue/phplint --force-accept-unsigned
+* sudo phive install -g composer phpdocumentor infection phpcs phpcbf phploc phpbench 
+* sudo phive install -g overtrue/phplint --force-accept-unsigned
 * composer install
 * composer all

examples/3teams.php

@@ -20,9 +20,9 @@ $team2 = new Team($p2, $gameInfo->getDefaultRating());
 $team3 = new Team($p3, $gameInfo->getDefaultRating());
 
 
-for($i = 0; $i < 5; ++$i) {
+for ($i = 0; $i < 5; ++$i) {
     echo "Iteration: " . $i . PHP_EOL;
-    $teams = Teams::concat($team1, $team2, $team3);
+    $teams = [$team1, $team2, $team3];
 
     $calculator = new FactorGraphTrueSkillCalculator();
 
@@ -32,10 +32,7 @@ for($i = 0; $i < 5; ++$i) {
     $team2 = new Team($p2, $newRatings->getRating($p2));
     $team3 = new Team($p3, $newRatings->getRating($p3));
 
-    echo "P1: ". $newRatings->getRating($p1)->getConservativeRating() . PHP_EOL;
+    echo "P1: " . $newRatings->getRating($p1)->getConservativeRating() . PHP_EOL;
-    echo "P2: ". $newRatings->getRating($p2)->getConservativeRating() . PHP_EOL;
+    echo "P2: " . $newRatings->getRating($p2)->getConservativeRating() . PHP_EOL;
-    echo "P3: ". $newRatings->getRating($p3)->getConservativeRating() . PHP_EOL;
+    echo "P3: " . $newRatings->getRating($p3)->getConservativeRating() . PHP_EOL;
 }
-
-
-

examples/basic.php

@@ -19,9 +19,9 @@ $team1 = new Team($p1, $gameInfo->getDefaultRating());
 $team2 = new Team($p2, $gameInfo->getDefaultRating());
 
 
-for($i = 0; $i < 5; ++$i) {
+for ($i = 0; $i < 5; ++$i) {
     echo "Iteration: " . $i . PHP_EOL;
-    $teams = Teams::concat($team1, $team2);
+    $teams = [$team1, $team2];
 
     $calculator = new TwoPlayerTrueSkillCalculator();
 
@@ -30,9 +30,6 @@ for($i = 0; $i < 5; ++$i) {
     $team1 = new Team($p1, $newRatings->getRating($p1));
     $team2 = new Team($p2, $newRatings->getRating($p2));
 
-    echo "P1: ". $newRatings->getRating($p1)->getConservativeRating() . PHP_EOL;
+    echo "P1: " . $newRatings->getRating($p1)->getConservativeRating() . PHP_EOL;
-    echo "P2: ". $newRatings->getRating($p2)->getConservativeRating() . PHP_EOL;
+    echo "P2: " . $newRatings->getRating($p2)->getConservativeRating() . PHP_EOL;
 }
-
-
-

examples/motogp/goat.php

@@ -0,0 +1,90 @@
+<?php
+
+require __DIR__ . "/../../vendor/autoload.php";
+
+use League\Csv\Reader;
+use League\Csv\Statement;
+use DNW\Skills\TrueSkill\FactorGraphTrueSkillCalculator;
+use DNW\Skills\GameInfo;
+use DNW\Skills\Player;
+use DNW\Skills\Team;
+use DNW\Skills\Teams;
+
+//load the CSV document from a stream
+$stream = fopen('motogp.csv', 'r');
+$csv = Reader::createFromStream($stream);
+$csv->setDelimiter(',');
+$csv->setHeaderOffset(0);
+
+//build a statement
+$stmt = Statement::create()->where(static fn (array $record): bool => $record['category'] == "MotoGP" ||  $record['category'] == "500cc");
+
+/**
+ * @var $riders Player[]
+ */
+$riders = [];
+//query your records from the document
+$records = $stmt->process($csv);
+
+$gameInfo = new GameInfo();
+$calculator = new FactorGraphTrueSkillCalculator();
+$first_record = $records->first();
+$year_race = $first_record['year'] . '_' . $first_record['sequence'] . '_' . $first_record['category'];
+
+$race_rate = [];
+foreach ($records as $record) {
+    if ($year_race !== $record['year'] . '_' . $record['sequence'] . '_' . $record['category']) {
+        //Calculate the old race
+        $newRatings = $calculator->calculateNewRatings($gameInfo, $teams, $pos);
+
+        //update ratings
+        $highest_rate = 0;
+        $highest_rider = "";
+        foreach ($riders as $rider) {
+            //echo $rider['P']->getId().": ". $newRatings->getRating($rider['P'])->getConservativeRating() . PHP_EOL;
+            $rider['T']->setRating($rider['P'], $newRatings->getRating($rider['P']));
+            if ($newRatings->getRating($rider['P'])->getConservativeRating() > $highest_rate) {
+                $highest_rate = $newRatings->getRating($rider['P'])->getConservativeRating();
+                $highest_rider = $rider['P']->getId();
+            }
+        }
+
+        echo sprintf('Highest rider: %s => %s', $highest_rider, $highest_rate) . PHP_EOL;
+
+        foreach ($global_riders as $r) {
+            $rate = $r['T']->getRating($r['P'])->getConservativeRating();
+
+            $race_rate[$year_race][$r['P']->getId()] = $rate;
+            if (! isset($top_rating[$r['P']->getId()]) || $top_rating[$r['P']->getId()] < $rate) {
+                $top_rating[$r['P']->getId()] = $rate;
+            }
+        }
+
+        //prepare for next race
+        $year_race = $record['year'] . '_' . $record['sequence'] . '_' . $record['category'];
+        $races[] = ['year' => $record['year'], 'race' => $record['sequence'], 'circuit' => $record['circuit_name']];
+        echo "New Race: " . $year_race . ' => ' . $record['circuit_name'] . PHP_EOL;
+        $riders = [];
+        $teams = [];
+        $pos = [];
+    }
+
+    //Is it a new rider?
+    if (! isset($global_riders[$record['rider']])) {
+        $global_riders[$record['rider']]['P'] = new Player($record['rider_name']);
+        $global_riders[$record['rider']]['T'] = new Team($global_riders[$record['rider']]['P'], $gameInfo->getDefaultRating());
+        //echo "New Rider: ". $record['rider'] . " => ".$global_riders[$record['rider']]['P']->getId().PHP_EOL;
+    }
+
+    $riders[] = $global_riders[$record['rider']];
+    $teams[] = $global_riders[$record['rider']]['T'];
+    
+    //Position or DNF?
+    $pos[] = $record['position'] >= 1 ? $record['position'] : end($pos);
+}
+
+echo "All time top score" . PHP_EOL;
+asort($top_rating);
+foreach ($top_rating as $n => $r) {
+    echo sprintf('%s => %s', $n, $r) . PHP_EOL;
+}

infection.json5

@@ -1,8 +1,8 @@
 {
-    "$schema": "https://raw.githubusercontent.com/infection/infection/0.27.9/resources/schema.json",
+    "$schema": "https://raw.githubusercontent.com/infection/infection/0.29.6/resources/schema.json",
     "source": {
         "directories": [
-            "src"
+            "src/"
         ]
     },
     "logs": {

phpbench.json

@@ -4,13 +4,11 @@
     "runner.php_disable_ini": true,
     "runner.retry_threshold": 10,
     "runner.iterations": 10,
-    "storage.xml_storage_path": "output/benchmarking/",
     "report.outputs": {
         "build-artifact": {
             "renderer": "html",
             "path": "output/benchmark.html",
             "title": "Benchmarking"
         }
-   }
+   }   
-   
 }

phpmd.baseline.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0"?>
+<phpmd-baseline>
+  <violation rule="PHPMD\Rule\Design\TooManyPublicMethods" file="src/Numerics/GaussianDistribution.php"/>
+  <violation rule="PHPMD\Rule\UnusedPrivateMethod" file="src/Numerics/GaussianDistribution.php" method="errorFunctionCumulativeTo"/>
+  <violation rule="PHPMD\Rule\UnusedPrivateMethod" file="src/Numerics/GaussianDistribution.php" method="inverseErrorFunctionCumulativeTo"/>
+  <violation rule="PHPMD\Rule\Design\WeightedMethodCount" file="src/Numerics/Matrix.php"/>
+  <violation rule="PHPMD\Rule\Design\CouplingBetweenObjects" file="src/TrueSkill/FactorGraphTrueSkillCalculator.php"/>
+  <violation rule="PHPMD\Rule\Design\CouplingBetweenObjects" file="src/TrueSkill/TrueSkillFactorGraph.php"/>
+</phpmd-baseline>

phpmd.ruleset.xml

@@ -0,0 +1,49 @@
+<?xml version="1.0"?>
+<ruleset name="TrueSkill custom PHPMD rules"
+         xmlns="http://pmd.sf.net/ruleset/1.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://pmd.sf.net/ruleset/1.0.0
+                     http://pmd.sf.net/ruleset_xml_schema.xsd"
+         xsi:noNamespaceSchemaLocation="
+                     http://pmd.sf.net/ruleset_xml_schema.xsd">
+    <description>
+        TrueSkill custom PHPMD rules
+    </description>
+
+    <!-- Import the entire unused code rule set -->
+    <rule ref="rulesets/cleancode.xml">
+        <exclude name="StaticAccess" />
+        <exclude name="ElseExpression" />
+    </rule>
+    <rule ref="rulesets/codesize.xml" >
+        <exclude name="TooManyMethods" />
+        <exclude name="TooManyPublicMethods" />
+    </rule>
+    <rule ref="rulesets/codesize.xml/TooManyMethods">
+        <priority>1</priority>
+        <properties>
+            <property name="ignorepattern" value="#^(set|get|test)|test$#i" />
+        </properties>
+    </rule>
+    <rule ref="rulesets/codesize.xml/TooManyPublicMethods">
+        <priority>1</priority>
+        <properties>
+            <property name="ignorepattern" value="#^(set|get|test)|test$#i" />
+        </properties>
+    </rule>
+
+
+    <!--rule ref="rulesets/controversial.xml" /-->
+    <rule ref="rulesets/design.xml" />
+    <rule ref="rulesets/naming.xml" >
+        <exclude name="LongClassName" />
+        <exclude name="ShortClassName" />
+        <exclude name="ShortVariable" />
+        <exclude name="LongVariable" />
+        <exclude name="ShortMethodName" />
+    </rule>
+    <rule ref="rulesets/unusedcode.xml" />
+
+    <!-- Import entire naming rule set and exclude rules -->
+
+</ruleset>

phpmetrics.json

@@ -1,21 +0,0 @@
-{
-    "composer": true,
-    "includes": [
-      "src"
-    ],
-    "excludes": [
-      "tests"
-    ],
-    "report": {
-      "html": "output/metrics/",
-      "json": "output/metrics/report.json"
-    },
-    "plugins": {
-      "git": {
-        "binary": "git"
-      },
-      "junit": {
-        "file": "output/test.xml"
-      }
-    }
-}

phpmetrics.yml

@@ -0,0 +1,18 @@
+---
+composer: true
+includes:
+    - src
+excludes:
+    - benchmark
+    - tests
+extensions:
+    - php
+report:
+  html: "output/metrics/"
+  json: "output/metrics/report.json"
+  violations: "/tmp/violations.xml"
+plugins:
+  git:
+    binary: git
+  junit:
+    file: "output/test.xml"

phpunit.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" backupGlobals="false" bootstrap="vendor/autoload.php" colors="true" processIsolation="false" stopOnFailure="false" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/10.2/phpunit.xsd" cacheDirectory=".phpunit.cache" backupStaticProperties="false"  displayDetailsOnTestsThatTriggerWarnings="true">
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/10.2/phpunit.xsd" backupGlobals="false" bootstrap="vendor/autoload.php" colors="true" processIsolation="false" stopOnFailure="false" cacheDirectory=".phpunit.cache" backupStaticProperties="false"  displayDetailsOnTestsThatTriggerWarnings="true" beStrictAboutCoverageMetadata="true" requireCoverageMetadata="true">
   <testsuites>
     <testsuite name="PHPSkills Test Suite">
       <directory>./tests/</directory>

src/FactorGraphs/Factor.php

@@ -8,26 +8,23 @@ use DNW\Skills\Guard;
 use DNW\Skills\HashMap;
 use Exception;
 
-abstract class Factor implements \Stringable
+abstract class Factor
 {
     /**
      * @var Message[] $messages
      */
     private array $messages = [];
 
-    private readonly HashMap $messageToVariableBinding;
+    private readonly HashMap $msgToVariableBinding;
-
-    private readonly string $name;
 
     /**
      * @var Variable[] $variables
      */
     private array $variables = [];
 
-    protected function __construct(string $name)
+    protected function __construct()
     {
-        $this->name = 'Factor[' . $name . ']';
+        $this->msgToVariableBinding = new HashMap();
-        $this->messageToVariableBinding = new HashMap();
     }
 
     /**
@@ -73,14 +70,14 @@ abstract class Factor implements \Stringable
     {
         Guard::argumentIsValidIndex($messageIndex, count($this->messages), 'messageIndex');
         $message = $this->messages[$messageIndex];
-        $variable = $this->messageToVariableBinding->getValue($message);
+        $variable = $this->msgToVariableBinding->getValue($message);
 
         return $this->updateMessageVariable($message, $variable);
     }
 
     protected function updateMessageVariable(Message $message, Variable $variable): float
     {
-        throw new Exception();
+        throw new Exception("Must override updateMessageVariable(" . $message::class . ", " . $variable::class . ")");
     }
 
     /**
@@ -88,7 +85,7 @@ abstract class Factor implements \Stringable
      */
     public function resetMarginals(): void
     {
-        $allValues = $this->messageToVariableBinding->getAllValues();
+        $allValues = $this->msgToVariableBinding->getAllValues();
         foreach ($allValues as $currentVariable) {
             $currentVariable->resetToPrior();
         }
@@ -104,7 +101,7 @@ abstract class Factor implements \Stringable
         Guard::argumentIsValidIndex($messageIndex, count($this->messages), 'messageIndex');
 
         $message = $this->messages[$messageIndex];
-        $variable = $this->messageToVariableBinding->getValue($message);
+        $variable = $this->msgToVariableBinding->getValue($message);
 
         return $this->sendMessageVariable($message, $variable);
     }
@@ -115,15 +112,10 @@ abstract class Factor implements \Stringable
 
     protected function createVariableToMessageBindingWithMessage(Variable $variable, Message $message): Message
     {
-        $this->messageToVariableBinding->setValue($message, $variable);
+        $this->msgToVariableBinding->setValue($message, $variable);
         $this->messages[] = $message;
         $this->variables[] = $variable;
 
         return $message;
     }
-
-    public function __toString(): string
-    {
-        return $this->name;
-    }
 }

src/FactorGraphs/FactorGraphLayer.php

@@ -17,7 +17,7 @@ abstract class FactorGraphLayer
     /**
      * @var array<int,array<int,Variable>>
      */
-    private array $outputVariablesGroups = [];
+    private array $outputVarGroups = [];
 
     /**
      * @var array<int,array<int,Variable>>
@@ -48,7 +48,7 @@ abstract class FactorGraphLayer
      */
     public function &getOutputVariablesGroups(): array
     {
-        return $this->outputVariablesGroups;
+        return $this->outputVarGroups;
     }
 
     /**
@@ -70,9 +70,9 @@ abstract class FactorGraphLayer
     /**
      * @param Schedule[] $itemsToSequence
      */
-    protected function scheduleSequence(array $itemsToSequence, string $name): ScheduleSequence
+    protected function scheduleSequence(array $itemsToSequence): ScheduleSequence
     {
-        return new ScheduleSequence($name, $itemsToSequence);
+        return new ScheduleSequence($itemsToSequence);
     }
 
     protected function addLayerFactor(Factor $factor): void

src/FactorGraphs/FactorList.php

@@ -26,12 +26,12 @@ class FactorList
         $listCount = count($this->list);
 
         for ($i = 0; $i < $listCount; ++$i) {
-            $f = $this->list[$i];
+            $factor = $this->list[$i];
 
-            $numberOfMessages = $f->getNumberOfMessages();
+            $numberOfMessages = $factor->getNumberOfMessages();
 
             for ($j = 0; $j < $numberOfMessages; ++$j) {
-                $sumLogZ += $f->sendMessageIndex($j);
+                $sumLogZ += $factor->sendMessageIndex($j);
             }
         }
 

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/Message.php

@@ -6,9 +6,9 @@ namespace DNW\Skills\FactorGraphs;
 
 use DNW\Skills\Numerics\GaussianDistribution;
 
-class Message implements \Stringable
+class Message
 {
-    public function __construct(private GaussianDistribution $value, private readonly string $name)
+    public function __construct(private GaussianDistribution $value)
     {
     }
 
@@ -21,9 +21,4 @@ class Message implements \Stringable
     {
         $this->value = $value;
     }
-
-    public function __toString(): string
-    {
-        return $this->name;
-    }
 }

src/FactorGraphs/Schedule.php

@@ -4,16 +4,7 @@ declare(strict_types=1);
 
 namespace DNW\Skills\FactorGraphs;
 
-abstract class Schedule implements \Stringable
+abstract class Schedule
 {
-    protected function __construct(private readonly string $name)
-    {
-    }
-
     abstract public function visit(int $depth = -1, int $maxDepth = 0): float;
-
-    public function __toString(): string
-    {
-        return $this->name;
-    }
 }

src/FactorGraphs/ScheduleLoop.php

@@ -6,9 +6,8 @@ namespace DNW\Skills\FactorGraphs;
 
 class ScheduleLoop extends Schedule
 {
-    public function __construct(string $name, private readonly Schedule $scheduleToLoop, private readonly float $maxDelta)
+    public function __construct(private readonly Schedule $scheduleToLoop, private readonly float $maxDelta)
     {
-        parent::__construct($name);
     }
 
     public function visit(int $depth = -1, int $maxDepth = 0): float

src/FactorGraphs/ScheduleSequence.php

@@ -9,9 +9,8 @@ class ScheduleSequence extends Schedule
     /**
      * @param Schedule[] $schedules
      */
-    public function __construct(string $name, private readonly array $schedules)
+    public function __construct(private readonly array $schedules)
     {
-        parent::__construct($name);
     }
 
     public function visit(int $depth = -1, int $maxDepth = 0): float

src/FactorGraphs/ScheduleStep.php

@@ -6,15 +6,12 @@ namespace DNW\Skills\FactorGraphs;
 
 class ScheduleStep extends Schedule
 {
-    public function __construct(string $name, private readonly Factor $factor, private readonly int $index)
+    public function __construct(private readonly Factor $factor, private readonly int $index)
     {
-        parent::__construct($name);
     }
 
     public function visit(int $depth = -1, int $maxDepth = 0): float
     {
-        $currentFactor = $this->factor;
+        return $this->factor->updateMessageIndex($this->index);
-
-        return $currentFactor->updateMessageIndex($this->index);
     }
 }

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 readonly 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

@@ -6,21 +6,21 @@ namespace DNW\Skills\FactorGraphs;
 
 class VariableFactory
 {
-    public function __construct(private \Closure $variablePriorInitializer)
+    public function __construct(private readonly \Closure $varPriorInitializer)
     {
     }
 
-    public function createBasicVariable(string $name): Variable
+    public function createBasicVariable(): Variable
     {
-        $initializer = $this->variablePriorInitializer;
+        $initializer = $this->varPriorInitializer;
 
-        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;
+        $initializer = $this->varPriorInitializer;
 
-        return new KeyedVariable($key, $name, $initializer());
+        return new KeyedVariable($key, $initializer());
     }
 }

src/GameInfo.php

@@ -27,7 +27,7 @@ class GameInfo
 
     public function __construct(
         private readonly float $initialMean = self::DEFAULT_INITIAL_MEAN,
-        private readonly float $initialStandardDeviation = self::DEFAULT_INITIAL_STANDARD_DEVIATION,
+        private readonly float $initialStdDev = self::DEFAULT_INITIAL_STANDARD_DEVIATION,
         private readonly float $beta = self::DEFAULT_BETA,
         private readonly float $dynamicsFactor = self::DEFAULT_DYNAMICS_FACTOR,
         private readonly float $drawProbability = self::DEFAULT_DRAW_PROBABILITY
@@ -42,7 +42,7 @@ class GameInfo
 
     public function getInitialStandardDeviation(): float
     {
-        return $this->initialStandardDeviation;
+        return $this->initialStdDev;
     }
 
     public function getBeta(): float
@@ -62,6 +62,6 @@ class GameInfo
 
     public function getDefaultRating(): Rating
     {
-        return new Rating($this->initialMean, $this->initialStandardDeviation);
+        return new Rating($this->initialMean, $this->initialStdDev);
     }
 }

src/HashMap.php

@@ -19,16 +19,16 @@ class HashMap
      */
     private array $hashToKey = [];
 
-    public function getValue(string|object $key): mixed
+    public function getValue(object $key): mixed
     {
-        $hash = self::getHash($key);
+        $hash = spl_object_id($key);
 
         return $this->hashToValue[$hash];
     }
 
-    public function setValue(string|object $key, mixed $value): self
+    public function setValue(object $key, mixed $value): self
     {
-        $hash = self::getHash($key);
+        $hash = spl_object_id($key);
         $this->hashToKey[$hash] = $key;
         $this->hashToValue[$hash] = $value;
 
@@ -55,13 +55,4 @@ class HashMap
     {
         return count($this->hashToKey);
     }
-
-    private static function getHash(string|object $key): string
-    {
-        if (is_object($key)) {
-            return spl_object_hash($key);
-        }
-
-        return $key;
-    }
 }

src/Numerics/BasicMath.php

@@ -13,15 +13,15 @@ namespace DNW\Skills\Numerics;
 class BasicMath
 {
     /**
-     * Squares the input (x^2 = x * x)
+     * Squares the input (input^2 = input * input)
      *
-     * @param $x Value to square (x)
+     * @param $input Value to square (input)
      *
-     * @return float The squared value (x^2)
+     * @return float The squared value (input^2)
      */
-    public static function square(float $x): float
+    public static function square(float $input): float
     {
-        return $x * $x;
+        return $input * $input;
     }
 
     /**

src/Numerics/GaussianDistribution.php

@@ -10,8 +10,12 @@ namespace DNW\Skills\Numerics;
  * @author    Jeff Moser <jeff@moserware.com>
  * @copyright 2010 Jeff Moser
  */
-class GaussianDistribution implements \Stringable
+class GaussianDistribution
 {
+    private const DEFAULT_STANDARD_DEVIATION = 1.0;
+
+    private const DEFAULT_MEAN = 0.0;
+
     /**
      * Square Root 2π.
      * Precalculated constant for performance reasons
@@ -31,23 +35,26 @@ class GaussianDistribution implements \Stringable
     private const M_LOG_SQRT_2_PI = 0.9189385332046727417803297364056176398613974736377834128171515404;
 
     // precision and precisionMean are used because they make multiplying and dividing simpler
-    // (the the accompanying math paper for more details)
+    // (see the accompanying math paper for more details)
-    private float $precision;
+    private float $precision = 1.0;
 
-    private float $precisionMean;
+    private float $precisionMean = 0.0;
 
-    private float $variance;
+    private float $variance = 1.0;
 
-    public function __construct(private float $mean = 0.0, private float $standardDeviation = 1.0)
+    public function __construct(private float $mean = self::DEFAULT_MEAN, private float $standardDeviation = self::DEFAULT_STANDARD_DEVIATION)
     {
-        $this->variance = BasicMath::square($standardDeviation);
+        if ($mean == self::DEFAULT_MEAN && $standardDeviation == self::DEFAULT_STANDARD_DEVIATION) {
+            //Use all the defaults
+            return;
+        }
 
+        $this->variance = BasicMath::square($standardDeviation);
         if ($this->variance != 0) {
             $this->precision = 1.0 / $this->variance;
             $this->precisionMean = $this->precision * $this->mean;
         } else {
             $this->precision = \INF;
-
             $this->precisionMean = $this->mean == 0 ? 0 : \INF;
         }
     }
@@ -167,7 +174,7 @@ class GaussianDistribution implements \Stringable
         BasicMath::square($meanDifference) / (2 * $varianceDifference);
     }
 
-    public static function at(float $x, float $mean = 0.0, float $standardDeviation = 1.0): float
+    public static function at(float $var, float $mean = 0.0, float $standardDeviation = 1.0): float
     {
         // See http://mathworld.wolfram.com/NormalDistribution.html
         //                1              -(x-mean)^2 / (2*stdDev^2)
@@ -175,22 +182,22 @@ class GaussianDistribution implements \Stringable
         //        stdDev * sqrt(2*pi)
 
         $multiplier = 1.0 / ($standardDeviation * self::M_SQRT_2_PI);
-        $expPart = exp((-1.0 * BasicMath::square($x - $mean)) / (2 * BasicMath::square($standardDeviation)));
+        $expPart = exp((-1.0 * BasicMath::square($var - $mean)) / (2 * BasicMath::square($standardDeviation)));
 
         return $multiplier * $expPart;
     }
 
-    public static function cumulativeTo(float $x, float $mean = 0.0, float $standardDeviation = 1.0): float
+    public static function cumulativeTo(float $var): float
     {
-        $result = GaussianDistribution::errorFunctionCumulativeTo(-M_SQRT1_2 * $x);
+        $result = GaussianDistribution::errorFunctionCumulativeTo(-M_SQRT1_2 * $var);
 
         return 0.5 * $result;
     }
 
-    private static function errorFunctionCumulativeTo(float $x): float
+    private static function errorFunctionCumulativeTo(float $var): float
     {
         // Derived from page 265 of Numerical Recipes 3rd Edition
-        $z = abs($x);
+        $z = abs($var);
 
         $t = 2.0 / (2.0 + $z);
         $ty = 4 * $t - 2;
@@ -238,13 +245,12 @@ class GaussianDistribution implements \Stringable
 
         $ans = $t * exp(-$z * $z + 0.5 * ($coefficients[0] + $ty * $d) - $dd);
 
-        return ($x >= 0.0) ? $ans : (2.0 - $ans);
+        return ($var >= 0.0) ? $ans : (2.0 - $ans);
     }
 
     private static function inverseErrorFunctionCumulativeTo(float $p): float
     {
         // From page 265 of numerical recipes
-
         if ($p >= 2.0) {
             return -100;
         }
@@ -265,14 +271,9 @@ class GaussianDistribution implements \Stringable
         return ($p < 1.0) ? $x : -$x;
     }
 
-    public static function inverseCumulativeTo(float $x, float $mean = 0.0, float $standardDeviation = 1.0): float
+    public static function inverseCumulativeTo(float $var, float $mean = 0.0, float $standardDeviation = 1.0): float
     {
         // From numerical recipes, page 320
-        return $mean - M_SQRT2 * $standardDeviation * GaussianDistribution::inverseErrorFunctionCumulativeTo(2 * $x);
+        return $mean - M_SQRT2 * $standardDeviation * GaussianDistribution::inverseErrorFunctionCumulativeTo(2 * $var);
-    }
-
-    public function __toString(): string
-    {
-        return sprintf('mean=%.4f standardDeviation=%.4f', $this->mean, $this->standardDeviation);
     }
 }

src/Numerics/Matrix.php

@@ -60,13 +60,34 @@ class Matrix
         return $this->columnCount;
     }
 
+    private function checkRowCol(int $row, int $col): void
+    {
+        if ($row < 0) {
+            throw new Exception("Row negative");
+        }
+
+        if ($row >= $this->getRowCount()) {
+            throw new Exception("Row beyond range");
+        }
+
+        if ($col < 0) {
+            throw new Exception("Column negative");
+        }
+
+        if ($col >= $this->getColumnCount()) {
+            throw new Exception("Column beyond range");
+        }
+    }
+
     public function getValue(int $row, int $col): float|int
     {
+        $this->checkRowCol($row, $col);
         return $this->matrixRowData[$row][$col];
     }
 
     public function setValue(int $row, int $col, float|int $value): void
     {
+        $this->checkRowCol($row, $col);
         $this->matrixRowData[$row][$col] = $value;
     }
 
@@ -76,10 +97,10 @@ class Matrix
         $transposeMatrix = [];
 
         $rowMatrixData = $this->matrixRowData;
-        for ($currentRowTransposeMatrix = 0; $currentRowTransposeMatrix < $this->columnCount; ++$currentRowTransposeMatrix) {
+        for ($curRowTransposeMx = 0; $curRowTransposeMx < $this->columnCount; ++$curRowTransposeMx) {
-            for ($currentColumnTransposeMatrix = 0; $currentColumnTransposeMatrix < $this->rowCount; ++$currentColumnTransposeMatrix) {
+            for ($curColTransposeMx = 0; $curColTransposeMx < $this->rowCount; ++$curColTransposeMx) {
-                $transposeMatrix[$currentRowTransposeMatrix][$currentColumnTransposeMatrix] =
+                $transposeMatrix[$curRowTransposeMx][$curColTransposeMx] =
-                    $rowMatrixData[$currentColumnTransposeMatrix][$currentRowTransposeMatrix];
+                    $rowMatrixData[$curColTransposeMx][$curRowTransposeMx];
             }
         }
 
@@ -100,7 +121,7 @@ class Matrix
 
         if ($this->rowCount == 1) {
             // Really happy path :)
-            return $this->matrixRowData[0][0];
+            return $this->getValue(0, 0);
         }
 
         if ($this->rowCount == 2) {
@@ -109,10 +130,10 @@ class Matrix
             // | a b |
             // | c d |
             // The determinant is ad - bc
-            $a = $this->matrixRowData[0][0];
+            $a = $this->getValue(0, 0);
-            $b = $this->matrixRowData[0][1];
+            $b = $this->getValue(0, 1);
-            $c = $this->matrixRowData[1][0];
+            $c = $this->getValue(1, 0);
-            $d = $this->matrixRowData[1][1];
+            $d = $this->getValue(1, 1);
 
             return $a * $d - $b * $c;
         }
@@ -127,7 +148,7 @@ class Matrix
 
         // I expand along the first row
         for ($currentColumn = 0; $currentColumn < $this->columnCount; ++$currentColumn) {
-            $firstRowColValue = $this->matrixRowData[0][$currentColumn];
+            $firstRowColValue = $this->getValue(0, $currentColumn);
             $cofactor = $this->getCofactor(0, $currentColumn);
             $itemToAdd = $firstRowColValue * $cofactor;
             $result += $itemToAdd;
@@ -152,10 +173,10 @@ class Matrix
             // | d -b |
             // | -c a |
 
-            $a = $this->matrixRowData[0][0];
+            $a = $this->getValue(0, 0);
-            $b = $this->matrixRowData[0][1];
+            $b = $this->getValue(0, 1);
-            $c = $this->matrixRowData[1][0];
+            $c = $this->getValue(1, 0);
-            $d = $this->matrixRowData[1][1];
+            $d = $this->getValue(1, 1);
 
             return new SquareMatrix(
                 $d,
@@ -180,7 +201,7 @@ class Matrix
     public function getInverse(): Matrix|SquareMatrix
     {
         if (($this->rowCount == 1) && ($this->columnCount == 1)) {
-            return new SquareMatrix(1.0 / $this->matrixRowData[0][0]);
+            return new SquareMatrix(1.0 / $this->getValue(0, 0));
         }
 
         // Take the simple approach:
@@ -262,6 +283,7 @@ class Matrix
 
     private function getMinorMatrix(int $rowToRemove, int $columnToRemove): Matrix
     {
+        $this->checkRowCol($rowToRemove, $columnToRemove);
         // See http://en.wikipedia.org/wiki/Minor_(linear_algebra)
 
         // I'm going to use a horribly naïve algorithm... because I can :)
@@ -281,7 +303,7 @@ class Matrix
                     continue;
                 }
 
-                $result[$actualRow][$actualCol] = $this->matrixRowData[$currentRow][$currentColumn];
+                $result[$actualRow][$actualCol] = $this->getValue($currentRow, $currentColumn);
 
                 ++$actualCol;
             }
@@ -294,6 +316,7 @@ class Matrix
 
     public function getCofactor(int $rowToRemove, int $columnToRemove): float
     {
+        $this->checkRowCol($rowToRemove, $columnToRemove);
         // See http://en.wikipedia.org/wiki/Cofactor_(linear_algebra) for details
         // REVIEW: should things be reversed since I'm 0 indexed?
         $sum = $rowToRemove + $columnToRemove;
@@ -316,7 +339,7 @@ class Matrix
             for ($currentColumn = 0; $currentColumn < $this->columnCount; ++$currentColumn) {
                 $delta =
                     abs(
-                        $this->matrixRowData[$currentRow][$currentColumn] -
+                        $this->getValue($currentRow, $currentColumn) -
                         $otherMatrix->getValue($currentRow, $currentColumn)
                     );
 

src/PartialPlay.php

@@ -8,14 +8,14 @@ class PartialPlay
 {
     public static function getPartialPlayPercentage(Player $player): float
     {
-        $partialPlayPercentage = $player->getPartialPlayPercentage();
+        $partialPlayPct = $player->getPartialPlayPercentage();
 
         // HACK to get around bug near 0
-        $smallestPercentage = 0.0001;
+        $smallestPct = 0.0001;
-        if ($partialPlayPercentage < $smallestPercentage) {
+        if ($partialPlayPct < $smallestPct) {
-            return $smallestPercentage;
+            return $smallestPct;
         }
 
-        return $partialPlayPercentage;
+        return $partialPlayPct;
     }
 }

src/Player.php

@@ -7,33 +7,33 @@ namespace DNW\Skills;
 /**
  * Represents a player who has a Rating.
  */
-class Player implements ISupportPartialPlay, ISupportPartialUpdate, \Stringable
+class Player implements ISupportPartialPlay, ISupportPartialUpdate
 {
     private const DEFAULT_PARTIAL_PLAY_PERCENTAGE = 1.0; // = 100% play time
 
     private const DEFAULT_PARTIAL_UPDATE_PERCENTAGE = 1.0;
 
-    private readonly float $PartialPlayPercentage;
+    private readonly float $PartialPlayPct;
 
-    private readonly float $PartialUpdatePercentage;
+    private readonly float $PartialUpdatePct;
 
     /**
      * Constructs a player.
      *
-     * @param mixed  $Id                      The identifier for the player, such as a name.
+     * @param string|int $Id                      The identifier for the player, such as a name.
-     * @param float $partialPlayPercentage   The weight percentage to give this player when calculating a new rank.
+     * @param float $partialPlayPct   The weight percentage to give this player when calculating a new rank.
-     * @param float $partialUpdatePercentage Indicated how much of a skill update a player should receive where 0 represents no update and 1.0 represents 100% of the update.
+     * @param float $partialUpdatePct Indicated how much of a skill update a player should receive where 0 represents no update and 1.0 represents 100% of the update.
      */
     public function __construct(
         private readonly mixed $Id,
-        float $partialPlayPercentage = self::DEFAULT_PARTIAL_PLAY_PERCENTAGE,
+        float $partialPlayPct = self::DEFAULT_PARTIAL_PLAY_PERCENTAGE,
-        float $partialUpdatePercentage = self::DEFAULT_PARTIAL_UPDATE_PERCENTAGE
+        float $partialUpdatePct = self::DEFAULT_PARTIAL_UPDATE_PERCENTAGE
     )
     {
-        Guard::argumentInRangeInclusive($partialPlayPercentage, 0.0, 1.0, 'partialPlayPercentage');
+        Guard::argumentInRangeInclusive($partialPlayPct, 0.0, 1.0, 'partialPlayPercentage');
-        Guard::argumentInRangeInclusive($partialUpdatePercentage, 0, 1.0, 'partialUpdatePercentage');
+        Guard::argumentInRangeInclusive($partialUpdatePct, 0, 1.0, 'partialUpdatePercentage');
-        $this->PartialPlayPercentage = $partialPlayPercentage;
+        $this->PartialPlayPct = $partialPlayPct;
-        $this->PartialUpdatePercentage = $partialUpdatePercentage;
+        $this->PartialUpdatePct = $partialUpdatePct;
     }
 
     /**
@@ -49,7 +49,7 @@ class Player implements ISupportPartialPlay, ISupportPartialUpdate, \Stringable
      */
     public function getPartialPlayPercentage(): float
     {
-        return $this->PartialPlayPercentage;
+        return $this->PartialPlayPct;
     }
 
     /**
@@ -57,11 +57,6 @@ class Player implements ISupportPartialPlay, ISupportPartialUpdate, \Stringable
      */
     public function getPartialUpdatePercentage(): float
     {
-        return $this->PartialUpdatePercentage;
+        return $this->PartialUpdatePct;
-    }
-
-    public function __toString(): string
-    {
-        return (string)$this->Id;
     }
 }

src/PlayersRange.php

@@ -8,8 +8,4 @@ use DNW\Skills\Numerics\Range;
 
 class PlayersRange extends Range
 {
-    protected static function create(int $min, int $max): static
-    {
-        return new static($min, $max);
-    }
 }

src/Rating.php

@@ -9,7 +9,7 @@ use DNW\Skills\Numerics\GaussianDistribution;
 /**
  * Container for a player's rating.
  */
-class Rating implements \Stringable
+class Rating
 {
     private const CONSERVATIVE_STANDARD_DEVIATION_MULTIPLIER = 3;
 
@@ -73,9 +73,4 @@ class Rating implements \Stringable
 
         return new Rating($partialPosteriorGaussion->getMean(), $partialPosteriorGaussion->getStandardDeviation(), $prior->conservativeStandardDeviationMultiplier);
     }
-
-    public function __toString(): string
-    {
-        return sprintf('mean=%.4f, standardDeviation=%.4f', $this->mean, $this->standardDeviation);
-    }
 }

src/SkillCalculator.php

@@ -11,6 +11,12 @@ use Exception;
  */
 abstract class SkillCalculator
 {
+    public const NONE = 0x00;
+
+    public const PARTIAL_PLAY = 0x01;
+
+    public const PARTIAL_UPDATE = 0x02;
+
     protected function __construct(
         private readonly int $supportedOptions,
         private readonly TeamsRange $totalTeamsAllowed,
@@ -46,7 +52,7 @@ abstract class SkillCalculator
 
     public function isSupported(int $option): bool
     {
-        return (bool)($this->supportedOptions & $option) == $option;
+        return ($this->supportedOptions & $option) === $option;
     }
 
     /**
@@ -58,7 +64,7 @@ abstract class SkillCalculator
     }
 
     /**
-     * @param array<\DNW\Skills\Team> $teams
+     * @param Team[] $teams
      *
      * @throws \Exception
      */

src/SkillCalculatorSupportedOptions.php

@@ -1,14 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace DNW\Skills;
-
-class SkillCalculatorSupportedOptions
-{
-    public const NONE = 0x00;
-
-    public const PARTIAL_PLAY = 0x01;
-
-    public const PARTIAL_UPDATE = 0x02;
-}

src/Teams.php

@@ -1,23 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace DNW\Skills;
-
-class Teams
-{
-    /**
-     * @return Team[]
-     */
-    public static function concat(Team ...$args/*variable arguments*/): array
-    {
-        $result = [];
-
-        foreach ($args as $currentTeam) {
-            $localCurrentTeam = $currentTeam;
-            $result[] = $localCurrentTeam;
-        }
-
-        return $result;
-    }
-}

src/TeamsRange.php

@@ -8,8 +8,4 @@ use DNW\Skills\Numerics\Range;
 
 class TeamsRange extends Range
 {
-    protected static function create(int $min, int $max): static
-    {
-        return new static($min, $max);
-    }
 }

src/TrueSkill/FactorGraphTrueSkillCalculator.php

@@ -14,7 +14,6 @@ use DNW\Skills\PartialPlay;
 use DNW\Skills\PlayersRange;
 use DNW\Skills\RankSorter;
 use DNW\Skills\SkillCalculator;
-use DNW\Skills\SkillCalculatorSupportedOptions;
 use DNW\Skills\Team;
 use DNW\Skills\TeamsRange;
 use DNW\Skills\RatingContainer;
@@ -27,7 +26,7 @@ class FactorGraphTrueSkillCalculator extends SkillCalculator
 {
     public function __construct()
     {
-        parent::__construct(SkillCalculatorSupportedOptions::PARTIAL_PLAY | SkillCalculatorSupportedOptions::PARTIAL_UPDATE, TeamsRange::atLeast(2), PlayersRange::atLeast(1));
+        parent::__construct(SkillCalculator::PARTIAL_PLAY | SkillCalculator::PARTIAL_UPDATE, TeamsRange::atLeast(2), PlayersRange::atLeast(1));
     }
 
     /**
@@ -172,7 +171,8 @@ class FactorGraphTrueSkillCalculator extends SkillCalculator
 
         $currentColumn = 0;
 
-        for ($i = 0; $i < count($teamAssignmentsList) - 1; ++$i) {
+        $teamCnt = count($teamAssignmentsList);
+        for ($i = 0; $i < $teamCnt - 1; ++$i) {
             $currentTeam = $teamAssignmentsList[$i];
 
             // Need to add in 0's for all the previous players, since they're not

src/TrueSkill/Factors/GaussianFactor.php

@@ -32,7 +32,6 @@ abstract class GaussianFactor extends Factor
             $variable,
             new Message(
                 $newDistribution,
-                sprintf('message from %s to %s', (string)$this, (string)$variable)
             )
         );
     }

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(private readonly float $epsilon, Variable $variable)
-
-    public function __construct(float $epsilon, Variable $variable)
     {
-        parent::__construct(\sprintf('%s > %.2f', (string)$variable, $epsilon));
+        parent::__construct();
-        $this->epsilon = $epsilon;
         $this->createVariableToMessageBinding($variable);
     }
 

src/TrueSkill/Factors/GaussianLikelihoodFactor.php

@@ -21,7 +21,8 @@ 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));
+        //Likelihood of $variable1 going to $variable2
+        parent::__construct();
         $this->precision = 1.0 / $betaSquared;
         $this->createVariableToMessageBinding($variable1);
         $this->createVariableToMessageBinding($variable2);
@@ -59,9 +60,9 @@ class GaussianLikelihoodFactor extends GaussianFactor
             $a * ($marginal2->getPrecision() - $message2Value->getPrecision())
         );
 
-        $oldMarginalWithoutMessage = GaussianDistribution::divide($marginal1, $message1Value);
+        $oldMarginalWithoutMsg = GaussianDistribution::divide($marginal1, $message1Value);
 
-        $newMarginal = GaussianDistribution::multiply($oldMarginalWithoutMessage, $newMessage);
+        $newMarginal = GaussianDistribution::multiply($oldMarginalWithoutMsg, $newMessage);
 
         // Update the message and marginal
 

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));
+        //Prior value going to $variable
+        parent::__construct();
         $this->newMessage = new GaussianDistribution($mean, sqrt($variance));
         $newMessage = new Message(
-            GaussianDistribution::fromPrecisionMean(0, 0),
+            GaussianDistribution::fromPrecisionMean(0, 0)
-            sprintf('message from %s to %s', (string)$this, (string)$variable)
         );
 
         $this->createVariableToMessageBindingWithMessage($variable, $newMessage);

src/TrueSkill/Factors/GaussianWeightedSumFactor.php

@@ -19,9 +19,9 @@ use DNW\Skills\Numerics\GaussianDistribution;
 class GaussianWeightedSumFactor extends GaussianFactor
 {
     /**
-     * @var array<int[]> $variableIndexOrdersForWeights
+     * @var array<int[]> $varIndexOrdersForWeights
      */
-    private array $variableIndexOrdersForWeights = [];
+    private array $varIndexOrdersForWeights = [];
 
     /**
      * This following is used for convenience, for example, the first entry is [0, 1, 2]
@@ -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();
 
         // The first weights are a straightforward copy
         // v_0 = a_1*v_1 + a_2*v_2 + ... + a_n * v_n
@@ -58,9 +58,9 @@ class GaussianWeightedSumFactor extends GaussianFactor
         $variablesToSumLength = count($variablesToSum);
 
         // 0..n-1
-        $this->variableIndexOrdersForWeights[0] = [];
+        $this->varIndexOrdersForWeights[0] = [];
         for ($i = 0; $i < ($variablesToSumLength + 1); ++$i) {
-            $this->variableIndexOrdersForWeights[0][] = $i;
+            $this->varIndexOrdersForWeights[0][] = $i;
         }
 
         $variableWeightsLength = count($variableWeights);
@@ -113,7 +113,7 @@ class GaussianWeightedSumFactor extends GaussianFactor
             $currentWeights[$currentDestinationWeightIndex] = $finalWeight;
             $currentWeightsSquared[$currentDestinationWeightIndex] = BasicMath::square($finalWeight);
             $variableIndices[count($variableWeights)] = 0;
-            $this->variableIndexOrdersForWeights[] = $variableIndices;
+            $this->varIndexOrdersForWeights[] = $variableIndices;
 
             $this->weights[$weightsIndex] = $currentWeights;
             $this->weightsSquared[$weightsIndex] = $currentWeightsSquared;
@@ -160,9 +160,7 @@ class GaussianWeightedSumFactor extends GaussianFactor
 
         // The math works out so that 1/newPrecision = sum of a_i^2 /marginalsWithoutMessages[i]
         $inverseOfNewPrecisionSum = 0.0;
-        $anotherInverseOfNewPrecisionSum = 0.0;
         $weightedMeanSum = 0.0;
-        $anotherWeightedMeanSum = 0.0;
 
         $weightsSquaredLength = count($weightsSquared);
 
@@ -172,16 +170,11 @@ class GaussianWeightedSumFactor extends GaussianFactor
             $inverseOfNewPrecisionSum += $weightsSquared[$i] /
                 ($variables[$i + 1]->getValue()->getPrecision() - $messages[$i + 1]->getValue()->getPrecision());
 
-            $diff = GaussianDistribution::divide($variables[$i + 1]->getValue(), $messages[$i + 1]->getValue());
-            $anotherInverseOfNewPrecisionSum += $weightsSquared[$i] / $diff->getPrecision();
-
             $weightedMeanSum += $weights[$i]
                 *
                 ($variables[$i + 1]->getValue()->getPrecisionMean() - $messages[$i + 1]->getValue()->getPrecisionMean())
                 /
                 ($variables[$i + 1]->getValue()->getPrecision() - $messages[$i + 1]->getValue()->getPrecision());
-
-            $anotherWeightedMeanSum += $weights[$i] * $diff->getPrecisionMean() / $diff->getPrecision();
         }
 
         $newPrecision = 1.0 / $inverseOfNewPrecisionSum;
@@ -214,7 +207,7 @@ class GaussianWeightedSumFactor extends GaussianFactor
         $updatedMessages = [];
         $updatedVariables = [];
 
-        $indicesToUse = $this->variableIndexOrdersForWeights[$messageIndex];
+        $indicesToUse = $this->varIndexOrdersForWeights[$messageIndex];
         // The tricky part here is that we have to put the messages and variables in the same
         // order as the weights. Thankfully, the weights and messages share the same index numbers,
         // so we just need to make sure they're consistent
@@ -235,42 +228,4 @@ 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 +16,10 @@ use DNW\Skills\TrueSkill\TruncatedGaussianCorrectionFunctions;
  */
 class GaussianWithinFactor extends GaussianFactor
 {
-    private readonly float $epsilon;
+    public function __construct(private readonly float $epsilon, Variable $variable)
-
-    public function __construct(float $epsilon, Variable $variable)
     {
-        parent::__construct(sprintf('%s <= %.2f', (string)$variable, $epsilon));
+        //$epsilon <= $variable
-        $this->epsilon = $epsilon;
+        parent::__construct();
         $this->createVariableToMessageBinding($variable);
     }
 

src/TrueSkill/Layers/IteratedTeamDifferencesInnerLayer.php

@@ -15,8 +15,8 @@ class IteratedTeamDifferencesInnerLayer extends TrueSkillFactorGraphLayer
 {
     public function __construct(
         TrueSkillFactorGraph $parentGraph,
-        private readonly TeamPerformancesToTeamPerformanceDifferencesLayer $TeamPerformancesToTeamPerformanceDifferencesLayer,
+        private readonly TeamPerformancesToTeamPerformanceDifferencesLayer $teamPerformancesToTeamPerformanceDifferencesLayer,
-        private readonly TeamDifferencesComparisonLayer $TeamDifferencesComparisonLayer
+        private readonly TeamDifferencesComparisonLayer $teamDifferencesComparisonLayer
     )
     {
         parent::__construct($parentGraph);
@@ -25,20 +25,20 @@ class IteratedTeamDifferencesInnerLayer extends TrueSkillFactorGraphLayer
     public function getLocalFactors(): array
     {
         return array_merge(
-            $this->TeamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors(),
+            $this->teamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors(),
-            $this->TeamDifferencesComparisonLayer->getLocalFactors()
+            $this->teamDifferencesComparisonLayer->getLocalFactors()
         );
     }
 
     public function buildLayer(): void
     {
         $inputVariablesGroups = $this->getInputVariablesGroups();
-        $this->TeamPerformancesToTeamPerformanceDifferencesLayer->setInputVariablesGroups($inputVariablesGroups);
+        $this->teamPerformancesToTeamPerformanceDifferencesLayer->setInputVariablesGroups($inputVariablesGroups);
-        $this->TeamPerformancesToTeamPerformanceDifferencesLayer->buildLayer();
+        $this->teamPerformancesToTeamPerformanceDifferencesLayer->buildLayer();
 
-        $teamDifferencesOutputVariablesGroups = $this->TeamPerformancesToTeamPerformanceDifferencesLayer->getOutputVariablesGroups();
+        $teamDifferencesOutputVariablesGroups = $this->teamPerformancesToTeamPerformanceDifferencesLayer->getOutputVariablesGroups();
-        $this->TeamDifferencesComparisonLayer->setInputVariablesGroups($teamDifferencesOutputVariablesGroups);
+        $this->teamDifferencesComparisonLayer->setInputVariablesGroups($teamDifferencesOutputVariablesGroups);
-        $this->TeamDifferencesComparisonLayer->buildLayer();
+        $this->teamDifferencesComparisonLayer->buildLayer();
     }
 
     public function createPriorSchedule(): ?ScheduleSequence
@@ -56,24 +56,24 @@ class IteratedTeamDifferencesInnerLayer extends TrueSkillFactorGraphLayer
         }
 
         // When dealing with differences, there are always (n-1) differences, so add in the 1
-        $totalTeamDifferences = count($this->TeamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors());
+        $totalTeamDifferences = count($this->teamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors());
 
-        $localFactors = $this->TeamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
+        $localFactors = $this->teamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
 
         $firstDifferencesFactor = $localFactors[0];
         $lastDifferencesFactor = $localFactors[$totalTeamDifferences - 1];
 
+        //inner schedule
         return new ScheduleSequence(
-            'inner schedule',
             [
                 $loop,
+                //teamPerformanceToPerformanceDifferenceFactors[0] @ 1
                 new ScheduleStep(
-                    'teamPerformanceToPerformanceDifferenceFactors[0] @ 1',
                     $firstDifferencesFactor,
                     1
                 ),
+                //teamPerformanceToPerformanceDifferenceFactors[teamTeamDifferences = %d - 1] @ 2
                 new ScheduleStep(
-                    sprintf('teamPerformanceToPerformanceDifferenceFactors[teamTeamDifferences = %d - 1] @ 2', $totalTeamDifferences),
                     $lastDifferencesFactor,
                     2
                 ),
@@ -83,95 +83,96 @@ class IteratedTeamDifferencesInnerLayer extends TrueSkillFactorGraphLayer
 
     private function createTwoTeamInnerPriorLoopSchedule(): ScheduleSequence
     {
-        $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors = $this->TeamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
+        $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors = $this->teamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
-        $teamDifferencesComparisonLayerLocalFactors = $this->TeamDifferencesComparisonLayer->getLocalFactors();
+        $teamDifferencesComparisonLayerLocalFactors = $this->teamDifferencesComparisonLayer->getLocalFactors();
 
         $firstPerfToTeamDiff = $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors[0];
         $firstTeamDiffComparison = $teamDifferencesComparisonLayerLocalFactors[0];
         $itemsToSequence = [
+            //send team perf to perf differences
             new ScheduleStep(
-                'send team perf to perf differences',
                 $firstPerfToTeamDiff,
                 0
             ),
+            //send to greater than or within factor
             new ScheduleStep(
-                'send to greater than or within factor',
                 $firstTeamDiffComparison,
                 0
             ),
         ];
 
+        //loop of just two teams inner sequence
         return $this->scheduleSequence(
-            $itemsToSequence,
+            $itemsToSequence
-            'loop of just two teams inner sequence'
         );
     }
 
     private function createMultipleTeamInnerPriorLoopSchedule(): ScheduleLoop
     {
-        $totalTeamDifferences = count($this->TeamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors());
+        $totalTeamDifferences = count($this->teamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors());
 
         $forwardScheduleList = [];
 
         for ($i = 0; $i < $totalTeamDifferences - 1; ++$i) {
-            $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors = $this->TeamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
+            $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors = $this->teamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
-            $teamDifferencesComparisonLayerLocalFactors = $this->TeamDifferencesComparisonLayer->getLocalFactors();
+            $teamDifferencesComparisonLayerLocalFactors = $this->teamDifferencesComparisonLayer->getLocalFactors();
 
             $currentTeamPerfToTeamPerfDiff = $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors[$i];
             $currentTeamDiffComparison = $teamDifferencesComparisonLayerLocalFactors[$i];
 
+            //current forward schedule piece $i
             $currentForwardSchedulePiece =
                 $this->scheduleSequence(
                     [
+                        //team perf to perf diff
                         new ScheduleStep(
-                            sprintf('team perf to perf diff %d', $i),
                             $currentTeamPerfToTeamPerfDiff,
                             0
                         ),
+                        //greater than or within result factor
                         new ScheduleStep(
-                            sprintf('greater than or within result factor %d', $i),
                             $currentTeamDiffComparison,
                             0
                         ),
+                        //'team perf to perf diff factors
                         new ScheduleStep(
-                            sprintf('team perf to perf diff factors [%d], 2', $i),
                             $currentTeamPerfToTeamPerfDiff,
                             2
                         ),
-                    ],
+                    ]
-                    sprintf('current forward schedule piece %d', $i)
                 );
 
             $forwardScheduleList[] = $currentForwardSchedulePiece;
         }
 
-        $forwardSchedule = new ScheduleSequence('forward schedule', $forwardScheduleList);
+        //forward schedule
+        $forwardSchedule = new ScheduleSequence($forwardScheduleList);
 
         $backwardScheduleList = [];
 
         for ($i = 0; $i < $totalTeamDifferences - 1; ++$i) {
-            $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors = $this->TeamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
+            $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors = $this->teamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
-            $teamDifferencesComparisonLayerLocalFactors = $this->TeamDifferencesComparisonLayer->getLocalFactors();
+            $teamDifferencesComparisonLayerLocalFactors = $this->teamDifferencesComparisonLayer->getLocalFactors();
 
             $differencesFactor = $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors[$totalTeamDifferences - 1 - $i];
             $comparisonFactor = $teamDifferencesComparisonLayerLocalFactors[$totalTeamDifferences - 1 - $i];
             $performancesToDifferencesFactor = $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors[$totalTeamDifferences - 1 - $i];
 
+            //current backward schedule piece
             $currentBackwardSchedulePiece = new ScheduleSequence(
-                'current backward schedule piece',
                 [
+                    //teamPerformanceToPerformanceDifferenceFactors[totalTeamDifferences - 1 - %d] @ 0
                     new ScheduleStep(
-                        sprintf('teamPerformanceToPerformanceDifferenceFactors[totalTeamDifferences - 1 - %d] @ 0', $i),
                         $differencesFactor,
                         0
                     ),
+                    //greaterThanOrWithinResultFactors[totalTeamDifferences - 1 - %d] @ 0
                     new ScheduleStep(
-                        sprintf('greaterThanOrWithinResultFactors[totalTeamDifferences - 1 - %d] @ 0', $i),
                         $comparisonFactor,
                         0
                     ),
+                    //teamPerformanceToPerformanceDifferenceFactors[totalTeamDifferences - 1 - %d] @ 1
                     new ScheduleStep(
-                        sprintf('teamPerformanceToPerformanceDifferenceFactors[totalTeamDifferences - 1 - %d] @ 1', $i),
                         $performancesToDifferencesFactor,
                         1
                     ),
@@ -180,18 +181,19 @@ class IteratedTeamDifferencesInnerLayer extends TrueSkillFactorGraphLayer
             $backwardScheduleList[] = $currentBackwardSchedulePiece;
         }
 
-        $backwardSchedule = new ScheduleSequence('backward schedule', $backwardScheduleList);
+        //backward schedule
+        $backwardSchedule = new ScheduleSequence($backwardScheduleList);
 
         $forwardBackwardScheduleToLoop =
+            //forward Backward Schedule To Loop
             new ScheduleSequence(
-                'forward Backward Schedule To Loop',
                 [$forwardSchedule, $backwardSchedule]
             );
 
         $initialMaxDelta = 0.0001;
 
+        //loop with max delta
         return new ScheduleLoop(
-            sprintf('loop with max delta of %f', $initialMaxDelta),
             $forwardBackwardScheduleToLoop,
             $initialMaxDelta
         );

src/TrueSkill/Layers/PlayerPerformancesToTeamPerformancesLayer.php

@@ -7,8 +7,6 @@ namespace DNW\Skills\TrueSkill\Layers;
 use DNW\Skills\FactorGraphs\ScheduleStep;
 use DNW\Skills\FactorGraphs\ScheduleSequence;
 use DNW\Skills\PartialPlay;
-use DNW\Skills\Player;
-use DNW\Skills\Team;
 use DNW\Skills\TrueSkill\Factors\GaussianWeightedSumFactor;
 use DNW\Skills\FactorGraphs\Variable;
 use DNW\Skills\FactorGraphs\KeyedVariable;
@@ -23,14 +21,14 @@ 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);
 
             // REVIEW: Does it make sense to have groups of one?
-            $outputVariablesGroups = &$this->getOutputVariablesGroups();
+            $outputVarGroups = &$this->getOutputVariablesGroups();
-            $outputVariablesGroups[] = [$teamPerformance];
+            $outputVarGroups[] = [$teamPerformance];
         }
     }
 
@@ -38,12 +36,13 @@ class PlayerPerformancesToTeamPerformancesLayer extends TrueSkillFactorGraphLaye
     {
         $localFactors = $this->getLocalFactors();
 
+        //all player perf to team perf schedule
         return $this->scheduleSequence(
             array_map(
-                static fn($weightedSumFactor): ScheduleStep => new ScheduleStep('Perf to Team Perf Step', $weightedSumFactor, 0),
+                //Perf to Team Perf Step
+                static fn($weightedSumFactor): ScheduleStep => new ScheduleStep($weightedSumFactor, 0),
                 $localFactors
-            ),
+            )
-            'all player perf to team perf schedule'
         );
     }
 
@@ -75,26 +74,23 @@ class PlayerPerformancesToTeamPerformancesLayer extends TrueSkillFactorGraphLaye
             $localCurrentFactor = $currentFactor;
             $numberOfMessages = $localCurrentFactor->getNumberOfMessages();
             for ($currentIteration = 1; $currentIteration < $numberOfMessages; ++$currentIteration) {
+                //team sum perf
                 $allFactors[] = new ScheduleStep(
-                    'team sum perf @' . $currentIteration,
                     $localCurrentFactor,
                     $currentIteration
                 );
             }
         }
 
-        return $this->scheduleSequence($allFactors, "all of the team's sum iterations");
+        //all of the team's sum iterations
+        return $this->scheduleSequence($allFactors);
     }
 
     /**
-     * @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()), $team);
+        return $this->getParentFactorGraph()->getVariableFactory()->createBasicVariable();
-
-        $teamMemberNames = \implode(', ', $memberNames);
-
-        return $this->getParentFactorGraph()->getVariableFactory()->createBasicVariable('Team[' . $teamMemberNames . "]'s performance");
     }
 }

src/TrueSkill/Layers/PlayerPriorValuesToSkillsLayer.php

@@ -34,12 +34,12 @@ class PlayerPriorValuesToSkillsLayer extends TrueSkillFactorGraphLayer
             $localCurrentTeam = $currentTeam;
             $currentTeamSkills = [];
 
-            $currentTeamAllPlayers = $localCurrentTeam->getAllPlayers();
+            $curTeamAllPlayers = $localCurrentTeam->getAllPlayers();
-            foreach ($currentTeamAllPlayers as $currentTeamPlayer) {
+            foreach ($curTeamAllPlayers as $curTeamPlayer) {
-                $localCurrentTeamPlayer = $currentTeamPlayer;
+                $localCurTeamPlayer = $curTeamPlayer;
-                $currentTeamPlayerRating = $currentTeam->getRating($localCurrentTeamPlayer);
+                $curTeamPlayerRating = $currentTeam->getRating($localCurTeamPlayer);
-                $playerSkill = $this->createSkillOutputVariable($localCurrentTeamPlayer);
+                $playerSkill = $this->createSkillOutputVariable($localCurTeamPlayer);
-                $priorFactor = $this->createPriorFactor($currentTeamPlayerRating, $playerSkill);
+                $priorFactor = $this->createPriorFactor($curTeamPlayerRating, $playerSkill);
                 $this->addLayerFactor($priorFactor);
                 $currentTeamSkills[] = $playerSkill;
             }
@@ -53,12 +53,13 @@ class PlayerPriorValuesToSkillsLayer extends TrueSkillFactorGraphLayer
     {
         $localFactors = $this->getLocalFactors();
 
+        //All priors
         return $this->scheduleSequence(
             array_map(
-                static fn($prior): ScheduleStep => new ScheduleStep('Prior to Skill Step', $prior, 0),
+                //Prior to Skill Step
+                static fn($prior): ScheduleStep => new ScheduleStep($prior, 0),
                 $localFactors
-            ),
+            )
-            'All priors'
         );
     }
 
@@ -77,6 +78,6 @@ class PlayerPriorValuesToSkillsLayer extends TrueSkillFactorGraphLayer
         $parentFactorGraph = $this->getParentFactorGraph();
         $variableFactory = $parentFactorGraph->getVariableFactory();
 
-        return $variableFactory->createKeyedVariable($key, $key . "'s skill");
+        return $variableFactory->createKeyedVariable($key);
     }
 }

src/TrueSkill/Layers/PlayerSkillsToPerformancesLayer.php

@@ -15,25 +15,25 @@ class PlayerSkillsToPerformancesLayer extends TrueSkillFactorGraphLayer
 {
     public function buildLayer(): void
     {
-        $inputVariablesGroups = $this->getInputVariablesGroups();
+        $inputVarGroups = $this->getInputVariablesGroups();
-        $outputVariablesGroups = &$this->getOutputVariablesGroups();
+        $outputVarGroups = &$this->getOutputVariablesGroups();
 
-        foreach ($inputVariablesGroups as $currentTeam) {
+        foreach ($inputVarGroups as $currentTeam) {
             $currentTeamPlayerPerformances = [];
 
             /**
-             * @var Variable $playerSkillVariable
+             * @var Variable $playerSkillVar
              */
-            foreach ($currentTeam as $playerSkillVariable) {
+            foreach ($currentTeam as $playerSkillVar) {
-                $localPlayerSkillVariable = $playerSkillVariable;
+                $localPlayerSkillVar = $playerSkillVar;
-                $currentPlayer = ($localPlayerSkillVariable instanceof KeyedVariable) ? $localPlayerSkillVariable->getKey() : "";
+                $currentPlayer = ($localPlayerSkillVar instanceof KeyedVariable) ? $localPlayerSkillVar->getKey() : "";
                 $playerPerformance = $this->createOutputVariable($currentPlayer);
-                $newLikelihoodFactor = $this->createLikelihood($localPlayerSkillVariable, $playerPerformance);
+                $newLikelihoodFactor = $this->createLikelihood($localPlayerSkillVar, $playerPerformance);
                 $this->addLayerFactor($newLikelihoodFactor);
                 $currentTeamPlayerPerformances[] = $playerPerformance;
             }
 
-            $outputVariablesGroups[] = $currentTeamPlayerPerformances;
+            $outputVarGroups[] = $currentTeamPlayerPerformances;
         }
     }
 
@@ -48,19 +48,20 @@ class PlayerSkillsToPerformancesLayer extends TrueSkillFactorGraphLayer
 
     private function createOutputVariable(mixed $key): KeyedVariable
     {
-        return $this->getParentFactorGraph()->getVariableFactory()->createKeyedVariable($key, $key . "'s performance");
+        return $this->getParentFactorGraph()->getVariableFactory()->createKeyedVariable($key);
     }
 
     public function createPriorSchedule(): ?ScheduleSequence
     {
         $localFactors = $this->getLocalFactors();
 
+        //All skill to performance sending
         return $this->scheduleSequence(
             array_map(
-                static fn($likelihood): ScheduleStep => new ScheduleStep('Skill to Perf step', $likelihood, 0),
+                //Skill to Perf step
+                static fn($likelihood): ScheduleStep => new ScheduleStep($likelihood, 0),
                 $localFactors
-            ),
+            )
-            'All skill to performance sending'
         );
     }
 
@@ -68,12 +69,12 @@ class PlayerSkillsToPerformancesLayer extends TrueSkillFactorGraphLayer
     {
         $localFactors = $this->getLocalFactors();
 
+        //All skill to performance sending
         return $this->scheduleSequence(
             array_map(
-                static fn($likelihood): ScheduleStep => new ScheduleStep('name', $likelihood, 1),
+                static fn($likelihood): ScheduleStep => new ScheduleStep($likelihood, 1),
                 $localFactors
-            ),
+            )
-            'All skill to performance sending'
         );
     }
 }

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();
     }
 }

src/TrueSkill/TrueSkillFactorGraph.php

@@ -28,7 +28,7 @@ class TrueSkillFactorGraph extends FactorGraph
     /**
      * @var FactorGraphLayer[] $layers
      */
-    private array $layers;
+    private readonly array $layers;
 
     private readonly PlayerPriorValuesToSkillsLayer $priorLayer;
 
@@ -118,13 +118,14 @@ class TrueSkillFactorGraph extends FactorGraph
         $allLayersReverse = array_reverse($this->layers);
 
         foreach ($allLayersReverse as $currentLayer) {
-            $currentPosteriorSchedule = $currentLayer->createPosteriorSchedule();
+            $curPosteriorSchedule = $currentLayer->createPosteriorSchedule();
-            if ($currentPosteriorSchedule != NULL) {
+            if ($curPosteriorSchedule != NULL) {
-                $fullSchedule[] = $currentPosteriorSchedule;
+                $fullSchedule[] = $curPosteriorSchedule;
             }
         }
 
-        return new ScheduleSequence('Full schedule', $fullSchedule);
+        //Full schedule
+        return new ScheduleSequence($fullSchedule);
     }
 
     public function getUpdatedRatings(): RatingContainer

src/TrueSkill/TruncatedGaussianCorrectionFunctions.php

@@ -102,33 +102,33 @@ class TruncatedGaussianCorrectionFunctions
     }
 
     // the multiplicative correction of a double-sided truncated Gaussian with unit variance
-    public static function wWithinMarginScaled(float $teamPerformanceDifference, float $drawMargin, float $c): float
+    public static function wWithinMarginScaled(float $teamPerformanceDiff, float $drawMargin, float $c): float
     {
-        return self::wWithinMargin($teamPerformanceDifference / $c, $drawMargin / $c);
+        return self::wWithinMargin($teamPerformanceDiff / $c, $drawMargin / $c);
     }
 
     // From F#:
-    public static function wWithinMargin(float $teamPerformanceDifference, float $drawMargin): float
+    public static function wWithinMargin(float $teamPerformanceDiff, float $drawMargin): float
     {
-        $teamPerformanceDifferenceAbsoluteValue = abs($teamPerformanceDifference);
+        $teamPerformanceDiffAbsValue = abs($teamPerformanceDiff);
-        $denominator = GaussianDistribution::cumulativeTo($drawMargin - $teamPerformanceDifferenceAbsoluteValue)
+        $denominator = GaussianDistribution::cumulativeTo($drawMargin - $teamPerformanceDiffAbsValue)
             -
-            GaussianDistribution::cumulativeTo(-$drawMargin - $teamPerformanceDifferenceAbsoluteValue);
+            GaussianDistribution::cumulativeTo(-$drawMargin - $teamPerformanceDiffAbsValue);
 
         if ($denominator < 2.222758749e-162) {
             return 1.0;
         }
 
-        $vt = self::vWithinMargin($teamPerformanceDifferenceAbsoluteValue, $drawMargin);
+        $vt = self::vWithinMargin($teamPerformanceDiffAbsValue, $drawMargin);
 
         return $vt * $vt +
-        (($drawMargin - $teamPerformanceDifferenceAbsoluteValue)
+        (($drawMargin - $teamPerformanceDiffAbsValue)
             *
             GaussianDistribution::at(
-                $drawMargin - $teamPerformanceDifferenceAbsoluteValue
+                $drawMargin - $teamPerformanceDiffAbsValue
             )
-            - (-$drawMargin - $teamPerformanceDifferenceAbsoluteValue)
+            - (-$drawMargin - $teamPerformanceDiffAbsValue)
             *
-            GaussianDistribution::at(-$drawMargin - $teamPerformanceDifferenceAbsoluteValue)) / $denominator;
+            GaussianDistribution::at(-$drawMargin - $teamPerformanceDiffAbsValue)) / $denominator;
     }
 }

src/TrueSkill/TwoPlayerTrueSkillCalculator.php

@@ -13,9 +13,7 @@ use DNW\Skills\RankSorter;
 use DNW\Skills\Rating;
 use DNW\Skills\RatingContainer;
 use DNW\Skills\SkillCalculator;
-use DNW\Skills\SkillCalculatorSupportedOptions;
 use DNW\Skills\TeamsRange;
-use DNW\Skills\Team;
 
 /**
  * Calculates the new ratings for only two players.
@@ -27,7 +25,7 @@ class TwoPlayerTrueSkillCalculator extends SkillCalculator
 {
     public function __construct()
     {
-        parent::__construct(SkillCalculatorSupportedOptions::NONE, TeamsRange::exactly(2), PlayersRange::exactly(1));
+        parent::__construct(SkillCalculator::NONE, TeamsRange::exactly(2), PlayersRange::exactly(1));
     }
 
     /**

src/TrueSkill/TwoTeamTrueSkillCalculator.php

@@ -13,7 +13,6 @@ use DNW\Skills\RankSorter;
 use DNW\Skills\Rating;
 use DNW\Skills\RatingContainer;
 use DNW\Skills\SkillCalculator;
-use DNW\Skills\SkillCalculatorSupportedOptions;
 use DNW\Skills\Team;
 use DNW\Skills\TeamsRange;
 
@@ -26,7 +25,7 @@ class TwoTeamTrueSkillCalculator extends SkillCalculator
 {
     public function __construct()
     {
-        parent::__construct(SkillCalculatorSupportedOptions::NONE, TeamsRange::exactly(2), PlayersRange::atLeast(1));
+        parent::__construct(SkillCalculator::NONE, TeamsRange::exactly(2), PlayersRange::atLeast(1));
     }
 
     /**
@@ -126,9 +125,9 @@ class TwoTeamTrueSkillCalculator extends SkillCalculator
         }
 
         $selfTeamAllPlayers = $selfTeam->getAllPlayers();
-        foreach ($selfTeamAllPlayers as $selfTeamCurrentPlayer) {
+        foreach ($selfTeamAllPlayers as $selfTeamCurPlayer) {
-            $localSelfTeamCurrentPlayer = $selfTeamCurrentPlayer;
+            $localSelfTeamCurPlayer = $selfTeamCurPlayer;
-            $previousPlayerRating = $selfTeam->getRating($localSelfTeamCurrentPlayer);
+            $previousPlayerRating = $selfTeam->getRating($localSelfTeamCurPlayer);
 
             $meanMultiplier = (BasicMath::square($previousPlayerRating->getStandardDeviation()) + $tauSquared) / $c;
             $stdDevMultiplier = (BasicMath::square($previousPlayerRating->getStandardDeviation()) + $tauSquared) / BasicMath::square($c);
@@ -140,7 +139,7 @@ class TwoTeamTrueSkillCalculator extends SkillCalculator
                 (BasicMath::square($previousPlayerRating->getStandardDeviation()) + $tauSquared) * (1 - $w * $stdDevMultiplier)
             );
 
-            $newPlayerRatings->setRating($localSelfTeamCurrentPlayer, new Rating($newMean, $newStdDev));
+            $newPlayerRatings->setRating($localSelfTeamCurPlayer, new Rating($newMean, $newStdDev));
         }
     }
 

tests/FactorGraphs/ScheduleStepTest.php

@@ -1,19 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace DNW\Skills\Tests\FactorGraphs;
-
-use DNW\Skills\FactorGraphs\ScheduleStep;
-use DNW\Skills\FactorGraphs\Factor;
-use PHPUnit\Framework\TestCase;
-
-class ScheduleStepTest extends TestCase
-{
-    public function test(): void
-    {
-        $stub = $this->createStub(Factor::class);
-        $ss = new ScheduleStep('dummy', $stub, 0);
-        $this->assertEquals('dummy', (string)$ss);
-    }
-}

tests/FactorGraphs/VariableTest.php

@@ -7,19 +7,22 @@ namespace DNW\Skills\Tests\FactorGraphs;
 use DNW\Skills\FactorGraphs\Variable;
 use DNW\Skills\Numerics\GaussianDistribution;
 use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\UsesClass;
 
+#[CoversClass(Variable::class)]
+#[UsesClass(GaussianDistribution::class)]
 class VariableTest extends TestCase
 {
-    public function test(): void
+    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);
     }
 }

tests/GameInfoTest.php

@@ -5,8 +5,13 @@ declare(strict_types=1);
 namespace DNW\Skills\Tests;
 
 use DNW\Skills\GameInfo;
+use DNW\Skills\Rating;
 use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\UsesClass;
 
+#[CoversClass(GameInfo::class)]
+#[UsesClass(Rating::class)]
 class GameInfoTest extends TestCase
 {
     public function testMembers(): void
@@ -17,6 +22,6 @@ class GameInfoTest extends TestCase
         $this->assertEquals(3, $gi->getBeta());
         $this->assertEquals(4, $gi->getDynamicsFactor());
         $this->assertEquals(5, $gi->getDrawProbability());
-        $this->assertInstanceOf(\DNW\Skills\Rating::class, $gi->getDefaultRating());
+        $this->assertInstanceOf(Rating::class, $gi->getDefaultRating());
     }
 }

tests/GuardTest.php

@@ -7,27 +7,55 @@ namespace DNW\Skills\Tests;
 use DNW\Skills\Guard;
 use Exception;
 use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
 
+#[CoversClass(Guard::class)]
 class GuardTest extends TestCase
 {
-    public function testargumentIsValidIndex(): void
+    public function testargumentIsValidIndexArgumentAbove(): void
     {
         $this->expectException(Exception::class);
         $this->expectExceptionMessage('dummy is an invalid index');
         Guard::argumentIsValidIndex(10, 10, "dummy");
     }
 
-    public function testargumentIsValidIndex2(): void
+    public function testargumentIsValidIndexArgumentBelow(): void
     {
         $this->expectException(Exception::class);
         $this->expectExceptionMessage('dummy is an invalid index');
         Guard::argumentIsValidIndex(-1, 10, "dummy");
     }
 
-    public function testargumentInRangeInclusive(): void
+    public function testargumentIsValidIndexArgumentValid(): void
+    {
+        Guard::argumentIsValidIndex(0, 10, "dummy");
+        Guard::argumentIsValidIndex(1, 10, "dummy");
+        Guard::argumentIsValidIndex(9, 10, "dummy");
+        $this->expectNotToPerformAssertions();
+    }
+
+    public function testargumentInRangeInclusiveAbove(): void
     {
         $this->expectException(Exception::class);
         $this->expectExceptionMessage('dummy is not in the valid range [0, 100]');
         Guard::argumentInRangeInclusive(101, 0, 100, "dummy");
     }
+
+    public function testargumentInRangeInclusiveBelow(): void
+    {
+        $this->expectException(Exception::class);
+        $this->expectExceptionMessage('dummy is not in the valid range [0, 100]');
+        Guard::argumentInRangeInclusive(-1, 0, 100, "dummy");
+    }
+
+    public function testargumentInRangeInclusiveValid(): void
+    {
+        Guard::argumentInRangeInclusive(0, 0, 100, "dummy");
+        Guard::argumentInRangeInclusive(1, 0, 100, "dummy");
+        Guard::argumentInRangeInclusive(50, 0, 100, "dummy");
+        Guard::argumentInRangeInclusive(99, 0, 100, "dummy");
+        Guard::argumentInRangeInclusive(100, 0, 100, "dummy");
+
+        $this->expectNotToPerformAssertions();
+    }
 }

tests/HashMapTest.php

@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DNW\Skills\Tests;
+
+use DNW\Skills\HashMap;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use stdClass;
+
+#[CoversClass(HashMap::class)]
+class HashMapTest extends TestCase
+{
+    public function testHashmap(): void
+    {
+        $h = new HashMap();
+
+        $this->assertEquals([], $h->getAllKeys());
+        $this->assertEquals([], $h->getAllValues());
+
+
+        $o1 = new stdClass();
+        $o2 = new stdClass();
+
+        $h->setValue($o1, 1);
+        $h->setvalue($o2, 2);
+
+        $this->assertEquals([1, 2], $h->getAllValues());
+        $this->assertEquals([$o1, $o2], $h->getAllKeys());
+
+        $this->assertEquals(1, $h->getvalue($o1));
+        $this->assertEquals(2, $h->getvalue($o2));
+
+        $this->assertEquals(2, $h->count());
+    }
+}

tests/Numerics/BasicMathTest.php

@@ -6,7 +6,9 @@ namespace DNW\Skills\Tests\Numerics;
 
 use DNW\Skills\Numerics\BasicMath;
 use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
 
+#[CoversClass(BasicMath::class)]
 class BasicMathTest extends TestCase
 {
     public function testSquare(): void

tests/Numerics/GaussianDistributionTest.php

@@ -7,7 +7,11 @@ namespace DNW\Skills\Tests\Numerics;
 use DNW\Skills\Numerics\BasicMath;
 use DNW\Skills\Numerics\GaussianDistribution;
 use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\UsesClass;
 
+#[CoversClass(GaussianDistribution::class)]
+#[UsesClass(BasicMath::class)]
 class GaussianDistributionTest extends TestCase
 {
     private const ERROR_TOLERANCE = 0.000001;
@@ -88,6 +92,21 @@ class GaussianDistributionTest extends TestCase
         $m3s4 = new GaussianDistribution(3, 4);
         $lpn2 = GaussianDistribution::logProductNormalization($m1s2, $m3s4);
         $this->assertEqualsWithDelta(-2.5168046699816684, $lpn2, GaussianDistributionTest::ERROR_TOLERANCE);
+
+        $numerator = GaussianDistribution::fromPrecisionMean(1, 0);
+        $denominator = GaussianDistribution::fromPrecisionMean(1, 0);
+        $lrn  = GaussianDistribution::logProductNormalization($numerator, $denominator);
+        $this->assertEquals(0, $lrn);
+
+        $numerator = GaussianDistribution::fromPrecisionMean(1, 1);
+        $denominator = GaussianDistribution::fromPrecisionMean(1, 0);
+        $lrn  = GaussianDistribution::logProductNormalization($numerator, $denominator);
+        $this->assertEquals(0, $lrn);
+
+        $numerator = GaussianDistribution::fromPrecisionMean(1, 0);
+        $denominator = GaussianDistribution::fromPrecisionMean(1, 1);
+        $lrn  = GaussianDistribution::logProductNormalization($numerator, $denominator);
+        $this->assertEquals(0, $lrn);
     }
 
     public function testLogRatioNormalization(): void
@@ -97,6 +116,21 @@ class GaussianDistributionTest extends TestCase
         $m3s4 = new GaussianDistribution(3, 4);
         $lrn  = GaussianDistribution::logRatioNormalization($m1s2, $m3s4);
         $this->assertEqualsWithDelta(2.6157405972171204, $lrn, GaussianDistributionTest::ERROR_TOLERANCE);
+
+        $numerator = GaussianDistribution::fromPrecisionMean(1, 0);
+        $denominator = GaussianDistribution::fromPrecisionMean(1, 0);
+        $lrn  = GaussianDistribution::logRatioNormalization($numerator, $denominator);
+        $this->assertEquals(0, $lrn);
+
+        $numerator = GaussianDistribution::fromPrecisionMean(1, 1);
+        $denominator = GaussianDistribution::fromPrecisionMean(1, 0);
+        $lrn  = GaussianDistribution::logRatioNormalization($numerator, $denominator);
+        $this->assertEquals(0, $lrn);
+
+        $numerator = GaussianDistribution::fromPrecisionMean(1, 0);
+        $denominator = GaussianDistribution::fromPrecisionMean(1, 1);
+        $lrn  = GaussianDistribution::logRatioNormalization($numerator, $denominator);
+        $this->assertEquals(0, $lrn);
     }
 
     public function testAbsoluteDifference(): void
@@ -111,4 +145,27 @@ class GaussianDistributionTest extends TestCase
         $absDiff2 = GaussianDistribution::absoluteDifference($m1s2, $m3s4);
         $this->assertEqualsWithDelta(0.4330127018922193, $absDiff2, GaussianDistributionTest::ERROR_TOLERANCE);
     }
+
+    public function testSubtract(): void
+    {
+        // Verified with Ralf Herbrich's F# implementation
+        $standardNormal = new GaussianDistribution(0, 1);
+        $absDiff        = GaussianDistribution::subtract($standardNormal, $standardNormal);
+        $this->assertEqualsWithDelta(0.0, $absDiff, GaussianDistributionTest::ERROR_TOLERANCE);
+
+        $m1s2 = new GaussianDistribution(1, 2);
+        $m3s4 = new GaussianDistribution(3, 4);
+        $absDiff2 = GaussianDistribution::subtract($m1s2, $m3s4);
+        $this->assertEqualsWithDelta(0.4330127018922193, $absDiff2, GaussianDistributionTest::ERROR_TOLERANCE);
+    }
+
+    public function testfromPrecisionMean(): void
+    {
+        $gd = GaussianDistribution::fromPrecisionMean(0, 0);
+        $this->assertInfinite($gd->getVariance());
+        $this->assertInfinite($gd->getStandardDeviation());
+        $this->assertNan($gd->getMean());
+        $this->assertEquals(0, $gd->getPrecisionMean());
+        $this->assertEquals(0, $gd->getPrecision());
+    }
 }

tests/Numerics/MatrixTest.php

@@ -8,18 +8,97 @@ use DNW\Skills\Numerics\IdentityMatrix;
 use DNW\Skills\Numerics\Matrix;
 use DNW\Skills\Numerics\SquareMatrix;
 use DNW\Skills\Numerics\DiagonalMatrix;
+use DNW\Skills\Numerics\Vector;
 use PHPUnit\Framework\TestCase;
 use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\Attributes\UsesClass;
 use Exception;
 
 #[CoversClass(Matrix::class)]
-#[UsesClass(SquareMatrix::class)]
+#[CoversClass(SquareMatrix::class)]
-#[UsesClass(IdentityMatrix::class)]
+#[CoversClass(IdentityMatrix::class)]
-#[UsesClass(DiagonalMatrix::class)]
+#[CoversClass(DiagonalMatrix::class)]
+#[CoversClass(Vector::class)]
 // phpcs:disable PSR2.Methods.FunctionCallSignature,Generic.Functions.FunctionCallArgumentSpacing.TooMuchSpaceAfterComma
 class MatrixTest extends TestCase
 {
+    public function testEmptyMatrix(): void
+    {
+        $m1 = new Matrix();
+        $this->assertEquals(0, $m1->getRowCount());
+        $this->assertEquals(0, $m1->getColumnCount());
+
+        $m2 = new Matrix(0, 0);
+        $this->assertEquals(0, $m2->getRowCount());
+        $this->assertEquals(0, $m2->getColumnCount());
+
+        $this->assertEquals(new Matrix(), Matrix::multiply($m1, $m2));
+    }
+
+    public function testIndexing(): void
+    {
+        $m = new Matrix(5, 5);
+        $m->setValue(0, 0, 1);
+        $this->assertEquals(1, $m->getValue(0, 0));
+        $m->setValue(0, 1, 2);
+        $this->assertEquals(2, $m->getValue(0, 1));
+        $m->setValue(1, 0, 3);
+        $this->assertEquals(3, $m->getValue(1, 0));
+        $m->setValue(1, 1, 4);
+        $this->assertEquals(4, $m->getValue(1, 1));
+
+        $m->setValue(3, 3, 11);
+        $this->assertEquals(11, $m->getValue(3, 3));
+        $m->setValue(4, 3, 22);
+        $this->assertEquals(22, $m->getValue(4, 3));
+        $m->setValue(3, 4, 33);
+        $this->assertEquals(33, $m->getValue(3, 4));
+        $m->setValue(4, 4, 44);
+        $this->assertEquals(44, $m->getValue(4, 4));
+
+        try {
+            $m->getValue(-1, -1);
+            $this->fail("No exception");
+        } catch (Exception $exception) {
+            $this->assertInstanceOf(Exception::class, $exception);
+        }
+
+        try {
+            $m->getValue(-1, 0);
+            $this->fail("No exception");
+        } catch (Exception $exception) {
+            $this->assertInstanceOf(Exception::class, $exception);
+        }
+
+        try {
+            $m->getValue(0, -1);
+            $this->fail("No exception");
+        } catch (Exception $exception) {
+            $this->assertInstanceOf(Exception::class, $exception);
+        }
+
+        try {
+            $m->getValue(5, 5);
+            $this->fail("No exception");
+        } catch (Exception $exception) {
+            $this->assertInstanceOf(Exception::class, $exception);
+        }
+
+        try {
+            $m->getValue(5, 4);
+            $this->fail("No exception");
+        } catch (Exception $exception) {
+            $this->assertInstanceOf(Exception::class, $exception);
+        }
+
+        try {
+            $m->getValue(4, 5);
+            $this->fail("No exception");
+        } catch (Exception $exception) {
+            $this->assertInstanceOf(Exception::class, $exception);
+        }
+    }
+
     public function testOneByOneDeterminant(): void
     {
         $a = new SquareMatrix(1);
@@ -264,6 +343,15 @@ class MatrixTest extends TestCase
         $m2 = new Matrix(1, 1, [[1,1]]);
         Matrix::multiply($m1, $m2);
     }
+
+    public function testVector(): void
+    {
+        $vector = new Vector([1,2,3,4]);
+
+        $m1 = new Matrix(4, 1, [[1],[2],[3],[4]]);
+
+        $this->assertTrue($vector->equals($m1));
+    }
 }
 
 // phpcs:enable

tests/Numerics/RangeTest.php

@@ -6,8 +6,10 @@ namespace DNW\Skills\Tests\Numerics;
 
 use DNW\Skills\Numerics\Range;
 use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
 use Exception;
 
+#[CoversClass(Range::class)]
 class RangeTest extends TestCase
 {
     public function testConstructInvalidParam(): void

tests/PartialPlayTest.php

@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DNW\Skills\Tests;
+
+use DNW\Skills\PartialPlay;
+use DNW\Skills\Player;
+use DNW\Skills\Guard;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\UsesClass;
+
+#[CoversClass(PartialPlay::class)]
+#[UsesClass(Player::class)]
+#[UsesClass(Guard::class)]
+class PartialPlayTest extends TestCase
+{
+    public function testgetPartialPlayPercentage(): void
+    {
+        $p = new Player(1, 0.5);
+        $this->assertEquals($p->getPartialPlayPercentage(), PartialPlay::getPartialPlayPercentage($p));
+
+        $p = new Player(1, 0.000000);
+        $this->assertNotEquals(0.0, PartialPlay::getPartialPlayPercentage($p));
+    }
+}

tests/PlayerTest.php

@@ -5,14 +5,19 @@ declare(strict_types=1);
 namespace DNW\Skills\Tests;
 
 use DNW\Skills\Player;
+use DNW\Skills\Guard;
 use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\UsesClass;
 
+#[CoversClass(Player::class)]
+#[UsesClass(Guard::class)]
 class PlayerTest extends TestCase
 {
-    public function test(): void
+    public function testPlayerObjectGetterSetter(): void
     {
         $p = new Player('dummy', 0.1, 0.2);
-        $this->assertEquals('dummy', (string)$p);
+        $this->assertEquals('dummy', $p->getId());
         $this->assertEquals(0.1, $p->getPartialPlayPercentage());
         $this->assertEquals(0.2, $p->getPartialUpdatePercentage());
     }

tests/RankSorterTest.php

@@ -6,7 +6,9 @@ namespace DNW\Skills\Tests;
 
 use DNW\Skills\RankSorter;
 use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
 
+#[CoversClass(RankSorter::class)]
 class RankSorterTest extends TestCase
 {
     public function testSort(): void

tests/RatingContainerTest.php

@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DNW\Skills\Tests;
+
+use DNW\Skills\RatingContainer;
+use DNW\Skills\HashMap;
+use DNW\Skills\Player;
+use DNW\Skills\Rating;
+use DNW\Skills\Guard;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\UsesClass;
+
+#[CoversClass(RatingContainer::class)]
+#[UsesClass(Hashmap::class)]
+#[UsesClass(Player::class)]
+#[UsesClass(Rating::class)]
+#[UsesClass(Guard::class)]
+class RatingContainerTest extends TestCase
+{
+    public function testRatingContainer(): void
+    {
+        $rc = new RatingContainer();
+
+        $this->assertEquals([], $rc->getAllPlayers());
+        $this->assertEquals([], $rc->getAllRatings());
+        $this->assertEquals(0, $rc->count());
+
+        $p1 = new Player(1);
+        $p2 = new Player(2);
+
+        $r1 = new Rating(100, 10);
+        $r2 = new Rating(200, 20);
+
+        $rc->setRating($p1, $r1);
+        $rc->setRating($p2, $r2);
+
+        $this->assertEquals($r1, $rc->getRating($p1));
+        $this->assertEquals($r2, $rc->getRating($p2));
+
+        $this->assertEquals([$p1, $p2], $rc->getAllPlayers());
+        $this->assertEquals([$r1, $r2], $rc->getAllRatings());
+        $this->assertEquals(2, $rc->count());
+    }
+}

tests/RatingTest.php

@@ -5,8 +5,15 @@ declare(strict_types=1);
 namespace DNW\Skills\Tests;
 
 use DNW\Skills\Rating;
+use DNW\Skills\Numerics\BasicMath;
+use DNW\Skills\Numerics\GaussianDistribution;
 use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\UsesClass;
 
+#[CoversClass(Rating::class)]
+#[UsesClass(BasicMath::class)]
+#[UsesClass(GaussianDistribution::class)]
 class RatingTest extends TestCase
 {
     public function testGetRatingParameters(): void
@@ -15,7 +22,6 @@ class RatingTest extends TestCase
         $this->assertEquals(100, $rating->getMean());
         $this->assertEquals(10, $rating->getStandardDeviation());
         $this->assertEquals(50, $rating->getConservativeRating());
-        $this->assertEquals("mean=100.0000, standardDeviation=10.0000", (string)$rating);
     }
 
     public function testPartialUpdate(): void
@@ -26,10 +32,8 @@ class RatingTest extends TestCase
 
         $rating_partial = $rating->getPartialUpdate($ratingOld, $ratingNew, 0.5);
 
-
         $this->assertEquals(150, $rating_partial->getMean());
         $this->assertEquals(10, $rating_partial->getStandardDeviation());
         $this->assertEquals(100, $rating_partial->getConservativeRating());
-        $this->assertEquals("mean=150.0000, standardDeviation=10.0000", (string)$rating_partial);
     }
 }

tests/SkillCalculatorTest.php

@@ -0,0 +1,29 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DNW\Skills\Tests;
+
+use DNW\Skills\SkillCalculator;
+use DNW\Skills\TeamsRange;
+use DNW\Skills\PlayersRange;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\UsesClass;
+use PHPUnit\Framework\Attributes\RequiresPhpunit;
+
+#[CoversClass(SkillCalculator::class)]
+#[UsesClass(\DNW\Skills\Numerics\Range::class)]
+#[UsesClass(PlayersRange::class)]
+#[UsesClass(TeamsRange::class)]
+#[RequiresPhpunit('<12.0')]
+class SkillCalculatorTest extends TestCase
+{
+    public function testisSupported(): void
+    {
+        $calculator = $this->getMockForAbstractClass(SkillCalculator::class, [SkillCalculator::PARTIAL_PLAY, new TeamsRange(1, 2), new PlayersRange(1, 2)]);
+
+        $this->assertEquals(TRUE, $calculator->isSupported(SkillCalculator::PARTIAL_PLAY));
+        $this->assertEquals(FALSE, $calculator->isSupported(SkillCalculator::PARTIAL_UPDATE));
+    }
+}

tests/TeamTest.php

@@ -0,0 +1,69 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DNW\Skills\Tests;
+
+use DNW\Skills\Team;
+use DNW\Skills\RatingContainer;
+use DNW\Skills\HashMap;
+use DNW\Skills\Player;
+use DNW\Skills\Rating;
+use DNW\Skills\Guard;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\UsesClass;
+
+#[CoversClass(Team::class)]
+#[CoversClass(RatingContainer::class)]
+#[UsesClass(Hashmap::class)]
+#[UsesClass(Player::class)]
+#[UsesClass(Rating::class)]
+#[UsesClass(Guard::class)]
+class TeamTest extends TestCase
+{
+    public function testTeam(): void
+    {
+        $p1 = new Player(1);
+        $p2 = new Player(2);
+
+        $r1 = new Rating(100, 10);
+        $r2 = new Rating(200, 20);
+
+        $rc = new Team($p1, $r1);
+
+        $this->assertEquals($r1, $rc->getRating($p1));
+        $this->assertEquals([$p1], $rc->getAllPlayers());
+        $this->assertEquals([$r1], $rc->getAllRatings());
+        $this->assertEquals(1, $rc->count());
+
+        $rc->addPlayer($p2, $r2);
+
+        $this->assertEquals($r2, $rc->getRating($p2));
+
+        $this->assertEquals([$p1, $p2], $rc->getAllPlayers());
+        $this->assertEquals([$r1, $r2], $rc->getAllRatings());
+        $this->assertEquals(2, $rc->count());
+    }
+
+    public function testTeamConstructor(): void
+    {
+        $p = new Player(0);
+        $r = new Rating(100, 10);
+
+        $rc = new Team(NULL, NULL);
+        $this->assertEquals(0, $rc->count());
+
+        $rc = new Team($p, NULL);
+        $this->assertEquals(0, $rc->count());
+
+        $rc = new Team(NULL, $r);
+        $this->assertEquals(0, $rc->count());
+
+        $rc = new Team($p, $r);
+        $this->assertEquals($r, $rc->getRating($p));
+        $this->assertEquals([$p], $rc->getAllPlayers());
+        $this->assertEquals([$r], $rc->getAllRatings());
+        $this->assertEquals(1, $rc->count());
+    }
+}

tests/TrueSkill/DrawMarginTest.php

@@ -5,8 +5,15 @@ declare(strict_types=1);
 namespace DNW\Skills\Tests\TrueSkill;
 
 use DNW\Skills\TrueSkill\DrawMargin;
+use DNW\Skills\Numerics\BasicMath;
+use DNW\Skills\Numerics\GaussianDistribution;
 use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\UsesClass;
 
+#[CoversClass(DrawMargin::class)]
+#[UsesClass(BasicMath::class)]
+#[UsesClass(GaussianDistribution::class)]
 class DrawMarginTest extends TestCase
 {
     private const ERROR_TOLERANCE = 0.000001;
@@ -23,6 +30,6 @@ class DrawMarginTest extends TestCase
     private function assertDrawMargin(float $drawProbability, float $beta, float $expected): void
     {
         $actual = DrawMargin::getDrawMarginFromDrawProbability($drawProbability, $beta);
-        $this->assertEqualsWithDelta($expected, $actual, DrawMarginTest::ERROR_TOLERANCE);
+        $this->assertEqualsWithDelta($expected, $actual, self::ERROR_TOLERANCE);
     }
 }

tests/TrueSkill/FactorGraphTrueSkillCalculatorTest.php

@@ -4,11 +4,11 @@ declare(strict_types=1);
 
 namespace DNW\Skills\Tests\TrueSkill;
 
+use DNW\Skills\SkillCalculator;
 use DNW\Skills\GameInfo;
 use DNW\Skills\Player;
 use DNW\Skills\Team;
 use DNW\Skills\TrueSkill\FactorGraphTrueSkillCalculator;
-use DNW\Skills\SkillCalculatorSupportedOptions;
 use PHPUnit\Framework\TestCase;
 use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\Attributes\CoversNothing;
@@ -78,6 +78,6 @@ class FactorGraphTrueSkillCalculatorTest extends TestCase
     public function testMethodisSupported(): void
     {
         $calculator = new FactorGraphTrueSkillCalculator();
-        $this->assertEquals(TRUE, $calculator->isSupported(SkillCalculatorSupportedOptions::PARTIAL_PLAY));
+        $this->assertEquals(TRUE, $calculator->isSupported(SkillCalculator::PARTIAL_PLAY));
     }
 }

tests/TrueSkill/TrueSkillCalculatorTests.php

@@ -9,7 +9,6 @@ use DNW\Skills\Player;
 use DNW\Skills\Rating;
 use DNW\Skills\SkillCalculator;
 use DNW\Skills\Team;
-use DNW\Skills\Teams;
 use PHPUnit\Framework\TestCase;
 
 class TrueSkillCalculatorTests
@@ -70,7 +69,6 @@ class TrueSkillCalculatorTests
     // online calculator at http://atom.research.microsoft.com/trueskill/rankcalculator.aspx
     //
     // All match quality expected values came from the online calculator
-
     // In both cases, there may be some discrepancy after the first decimal point. I think this is due to my implementation
     // using slightly higher precision in GaussianDistribution.
 
@@ -86,7 +84,7 @@ class TrueSkillCalculatorTests
 
         $team1 = new Team($player1, $gameInfo->getDefaultRating());
         $team2 = new Team($player2, $gameInfo->getDefaultRating());
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
 
         $newRatings = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2]);
 
@@ -109,7 +107,7 @@ class TrueSkillCalculatorTests
         $team1 = new Team($player1, $gameInfo->getDefaultRating());
         $team2 = new Team($player2, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
 
         $newRatings = $calculator->calculateNewRatings($gameInfo, $teams, [1, 1]);
 
@@ -132,7 +130,7 @@ class TrueSkillCalculatorTests
         $team1 = new Team($player1, new Rating(1301.0007, 42.9232));
         $team2 = new Team($player2, new Rating(1188.7560, 42.5570));
 
-        $newRatings = $calculator->calculateNewRatings($gameInfo, Teams::concat($team1, $team2), [1, 2]);
+        $newRatings = $calculator->calculateNewRatings($gameInfo, [$team1, $team2], [1, 2]);
 
         $player1NewRating = $newRatings->getRating($player1);
         self::assertRating($testClass, 1304.7820836053318, 42.843513887848658, $player1NewRating);
@@ -153,7 +151,7 @@ class TrueSkillCalculatorTests
 
         $team2 = new Team($player2, new Rating(50, 12.5));
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
 
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 1]);
 
@@ -184,7 +182,7 @@ class TrueSkillCalculatorTests
         $team2->addPlayer($player2, $gameInfo->getDefaultRating());
         $team2->addPlayer($player3, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2]);
 
         // Winners
@@ -219,7 +217,7 @@ class TrueSkillCalculatorTests
         $team2->addPlayer($player3, $gameInfo->getDefaultRating());
         $team2->addPlayer($player4, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2]);
 
         // Winners
@@ -249,7 +247,7 @@ class TrueSkillCalculatorTests
         $team2->addPlayer($player2, new Rating(20, 7));
         $team2->addPlayer($player3, new Rating(25, 8));
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2]);
 
         // Winners
@@ -280,7 +278,7 @@ class TrueSkillCalculatorTests
         $team2->addPlayer($player3, $gameInfo->getDefaultRating());
         $team2->addPlayer($player4, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2]);
 
         // Winners
@@ -310,7 +308,7 @@ class TrueSkillCalculatorTests
         $team2->addPlayer($player2, $gameInfo->getDefaultRating());
         $team2->addPlayer($player3, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 1]);
 
         // Winners
@@ -341,7 +339,7 @@ class TrueSkillCalculatorTests
         $team2->addPlayer($player3, $gameInfo->getDefaultRating());
         $team2->addPlayer($player4, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 1]);
 
         // Winners
@@ -381,7 +379,7 @@ class TrueSkillCalculatorTests
         $team2->addPlayer($player7, $gameInfo->getDefaultRating());
         $team2->addPlayer($player8, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2]);
 
         // Winners
@@ -419,7 +417,7 @@ class TrueSkillCalculatorTests
 
         $gameInfo = new GameInfo();
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
         $newRatingsWinLoseExpected = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2]);
 
         // Winners
@@ -431,7 +429,7 @@ class TrueSkillCalculatorTests
         self::assertRating($testClass, 29.785, 3.958, $newRatingsWinLoseExpected->getRating($player4));
         self::assertRating($testClass, 30.879, 2.983, $newRatingsWinLoseExpected->getRating($player5));
 
-        $newRatingsWinLoseUpset = $calculator->calculateNewRatings($gameInfo, Teams::concat($team1, $team2), [2, 1]);
+        $newRatingsWinLoseUpset = $calculator->calculateNewRatings($gameInfo, [$team1, $team2], [2, 1]);
 
         // Winners
         self::assertRating($testClass, 32.012, 3.877, $newRatingsWinLoseUpset->getRating($player4));
@@ -463,7 +461,7 @@ class TrueSkillCalculatorTests
         $team2->addPlayer($player3, new Rating(25, 4));
         $team2->addPlayer($player4, new Rating(30, 3));
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 1]);
 
         // Winners
@@ -495,7 +493,7 @@ class TrueSkillCalculatorTests
         $team2->addPlayer($player3, new Rating(35, 7));
         $team2->addPlayer($player4, new Rating(40, 5));
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2]);
 
         // Winners
@@ -535,7 +533,7 @@ class TrueSkillCalculatorTests
         $team2->addPlayer($player7, $gameInfo->getDefaultRating());
         $team2->addPlayer($player8, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
 
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2]);
 
@@ -572,7 +570,7 @@ class TrueSkillCalculatorTests
         $team2->addPlayer($player3, $gameInfo->getDefaultRating());
         $team2->addPlayer($player4, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2);
+        $teams = [$team1, $team2];
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 1]);
 
         // Winners
@@ -598,7 +596,7 @@ class TrueSkillCalculatorTests
         $team2 = new Team($player2, $gameInfo->getDefaultRating());
         $team3 = new Team($player3, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2, $team3);
+        $teams = [$team1, $team2, $team3];
         $newRatings = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2, 3]);
 
         $player1NewRating = $newRatings->getRating($player1);
@@ -625,7 +623,7 @@ class TrueSkillCalculatorTests
         $team2 = new Team($player2, $gameInfo->getDefaultRating());
         $team3 = new Team($player3, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2, $team3);
+        $teams = [$team1, $team2, $team3];
         $newRatings = $calculator->calculateNewRatings($gameInfo, $teams, [1, 1, 1]);
 
         $player1NewRating = $newRatings->getRating($player1);
@@ -653,7 +651,7 @@ class TrueSkillCalculatorTests
         $team3 = new Team($player3, $gameInfo->getDefaultRating());
         $team4 = new Team($player4, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2, $team3, $team4);
+        $teams = [$team1, $team2, $team3, $team4];
 
         $newRatings = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2, 3, 4]);
 
@@ -687,7 +685,7 @@ class TrueSkillCalculatorTests
         $team4 = new Team($player4, $gameInfo->getDefaultRating());
         $team5 = new Team($player5, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2, $team3, $team4, $team5);
+        $teams = [$team1, $team2, $team3, $team4, $team5];
         $newRatings = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2, 3, 4, 5]);
 
         $player1NewRating = $newRatings->getRating($player1);
@@ -729,7 +727,7 @@ class TrueSkillCalculatorTests
         $team7 = new Team($player7, $gameInfo->getDefaultRating());
         $team8 = new Team($player8, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat($team1, $team2, $team3, $team4, $team5, $team6, $team7, $team8);
+        $teams = [$team1, $team2, $team3, $team4, $team5, $team6, $team7, $team8];
         $newRatings = $calculator->calculateNewRatings($gameInfo, $teams, [1, 1, 1, 1, 1, 1, 1, 1]);
 
         $player1NewRating = $newRatings->getRating($player1);
@@ -781,7 +779,7 @@ class TrueSkillCalculatorTests
         $team7 = new Team($player7, new Rating(40, 2));
         $team8 = new Team($player8, new Rating(45, 1));
 
-        $teams = Teams::concat($team1, $team2, $team3, $team4, $team5, $team6, $team7, $team8);
+        $teams = [$team1, $team2, $team3, $team4, $team5, $team6, $team7, $team8];
         $newRatings = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2, 3, 4, 5, 6, 7, 8]);
 
         $player1NewRating = $newRatings->getRating($player1);
@@ -849,24 +847,7 @@ class TrueSkillCalculatorTests
         $team15 = new Team($player15, $gameInfo->getDefaultRating());
         $team16 = new Team($player16, $gameInfo->getDefaultRating());
 
-        $teams = Teams::concat(
+        $teams = [$team1, $team2, $team3, $team4, $team5, $team6, $team7, $team8, $team9, $team10, $team11, $team12, $team13, $team14, $team15, $team16];
-            $team1,
-            $team2,
-            $team3,
-            $team4,
-            $team5,
-            $team6,
-            $team7,
-            $team8,
-            $team9,
-            $team10,
-            $team11,
-            $team12,
-            $team13,
-            $team14,
-            $team15,
-            $team16
-        );
 
         $newRatings = $calculator->calculateNewRatings(
             $gameInfo,
@@ -952,7 +933,7 @@ class TrueSkillCalculatorTests
         $team3->addPlayer($player7, new Rating(50, 5));
         $team3->addPlayer($player8, new Rating(30, 2));
 
-        $teams = Teams::concat($team1, $team2, $team3);
+        $teams = [$team1, $team2, $team3];
         $newRatingsWinLose = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2, 2]);
 
         // Winners
@@ -986,7 +967,7 @@ class TrueSkillCalculatorTests
         $team2->addPlayer($p2, $gameInfo->getDefaultRating());
         $team2->addPlayer($p3, $gameInfo->getDefaultRating());
 
-        $teams      = Teams::concat($team1, $team2);
+        $teams      = [$team1, $team2];
         $newRatings = $calculator->calculateNewRatings($gameInfo, $teams, [1, 2]);
 
         $p1NewRating = $newRatings->getRating($p1);

tests/TrueSkill/TruncatedGaussianCorrectionFunctionsTest.php

@@ -0,0 +1,54 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DNW\Skills\Tests\TrueSkill;
+
+use DNW\Skills\TrueSkill\TruncatedGaussianCorrectionFunctions;
+use DNW\Skills\Numerics\BasicMath;
+use DNW\Skills\Numerics\GaussianDistribution;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\UsesClass;
+
+#[CoversClass(TruncatedGaussianCorrectionFunctions::class)]
+#[UsesClass(BasicMath::class)]
+#[UsesClass(GaussianDistribution::class)]
+class TruncatedGaussianCorrectionFunctionsTest extends TestCase
+{
+    public function testvGreaterThan(): void
+    {
+        // Test values taken from Ralf Herbrich's F# TrueSkill implementation
+        $want = 0.4181660649773850;
+        $tVar = 0.7495591915280050;
+        $eps = 0.0631282276750071;
+        $this->assertEqualsWithDelta($want, TruncatedGaussianCorrectionFunctions::vExceedsMargin($tVar, $eps), 1e-6);
+    }
+    
+    public function testwGreaterThan(): void
+    {
+        // Test values taken from Ralf Herbrich's F# TrueSkill implementation
+        $want = 0.4619049929317120;
+        $tVar = 0.7495591915280050;
+        $eps = 0.0631282276750071;
+        $this->assertEqualsWithDelta($want, TruncatedGaussianCorrectionFunctions::wExceedsMargin($tVar, $eps), 1e-6);
+    }
+    
+    public function testvWithin(): void
+    {
+        // Test values taken from Ralf Herbrich's F# TrueSkill implementation
+        $want = -0.7485644072749330;
+        $tVar = 0.7495591915280050;
+        $eps = 0.0631282276750071;
+        $this->assertEqualsWithDelta($want, TruncatedGaussianCorrectionFunctions::vWithinMargin($tVar, $eps), 1e-6);
+    }
+    
+    public function testwWithin(): void
+    {
+        // Test values taken from Ralf Herbrich's F# TrueSkill implementation
+        $want = 0.9986734210033660;
+        $tVar = 0.7495591915280050;
+        $eps = 0.0631282276750071;
+        $this->assertEqualsWithDelta($want, TruncatedGaussianCorrectionFunctions::wWithinMargin($tVar, $eps), 1e-6);
+    }
+}

tests/TrueSkill/TwoPlayerTrueSkillCalculatorTest.php

@@ -17,7 +17,6 @@ class TwoPlayerTrueSkillCalculatorTest extends TestCase
     {
         $calculator = new TwoPlayerTrueSkillCalculator();
 
-        // We only support two players
         TrueSkillCalculatorTests::testAllTwoPlayerScenarios($this, $calculator);
     }
 }

tests/TrueSkill/TwoTeamTrueSkillCalculatorTest.php

@@ -9,7 +9,7 @@ use PHPUnit\Framework\TestCase;
 use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\Attributes\CoversNothing;
 
-//#[CoversClass(TwoTeamTrueSkillCalculator::class)]
+#[CoversClass(TwoTeamTrueSkillCalculator::class)]
 class TwoTeamTrueSkillCalculatorTest extends TestCase
 {
     #[CoversNothing]
@@ -17,7 +17,6 @@ class TwoTeamTrueSkillCalculatorTest extends TestCase
     {
         $calculator = new TwoTeamTrueSkillCalculator();
 
-        // We only support two players
         TrueSkillCalculatorTests::testAllTwoPlayerScenarios($this, $calculator);
         TrueSkillCalculatorTests::testAllTwoTeamScenarios($this, $calculator);
     }