Package update and implemented new fixes for Rector findings

.woodpecker.yml

@@ -1,3 +1,5 @@
+when:
+  - event: [push, tag]
 steps:
   - name: requirements
     image: composer
@@ -8,7 +10,7 @@ steps:
     commands:
       - php examples/3teams.php
       - php examples/basic.php
-  - name: dependencies
+  - name: test
     image: composer
     commands:
     - composer install

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
 {
     /**

composer.json

@@ -7,9 +7,9 @@
   },
   "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",
     "league/csv": "^9.0"
@@ -26,12 +26,14 @@
   },
   "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"
     ],
     "analyze": [
         "@analyze-phpstan",
@@ -47,10 +49,10 @@
     ],
     "all": [
       "@test",
-      "@document",
-      "@benchmark",
       "@lint",
       "@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

examples/3teams.php

@@ -20,7 +20,7 @@ $team2 = new Team($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;
     $teams = [$team1, $team2, $team3];
 
@@ -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 "P2: ". $newRatings->getRating($p2)->getConservativeRating() . PHP_EOL;
-    echo "P3: ". $newRatings->getRating($p3)->getConservativeRating() . PHP_EOL;
+    echo "P1: " . $newRatings->getRating($p1)->getConservativeRating() . PHP_EOL;
+    echo "P2: " . $newRatings->getRating($p2)->getConservativeRating() . PHP_EOL;
+    echo "P3: " . $newRatings->getRating($p3)->getConservativeRating() . PHP_EOL;
 }
-
-
-

examples/basic.php

@@ -19,7 +19,7 @@ $team1 = new Team($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;
     $teams = [$team1, $team2];
 
@@ -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 "P2: ". $newRatings->getRating($p2)->getConservativeRating() . PHP_EOL;
+    echo "P1: " . $newRatings->getRating($p1)->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

@@ -10,6 +10,5 @@
             "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"

src/FactorGraphs/Factor.php

@@ -15,7 +15,7 @@ abstract class Factor
      */
     private array $messages = [];
 
-    private readonly HashMap $messageToVariableBinding;
+    private readonly HashMap $msgToVariableBinding;
 
     /**
      * @var Variable[] $variables
@@ -24,7 +24,7 @@ abstract class Factor
 
     protected function __construct()
     {
-        $this->messageToVariableBinding = new HashMap();
+        $this->msgToVariableBinding = new HashMap();
     }
 
     /**
@@ -70,7 +70,7 @@ abstract class Factor
     {
         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);
     }
@@ -85,7 +85,7 @@ abstract class Factor
      */
     public function resetMarginals(): void
     {
-        $allValues = $this->messageToVariableBinding->getAllValues();
+        $allValues = $this->msgToVariableBinding->getAllValues();
         foreach ($allValues as $currentVariable) {
             $currentVariable->resetToPrior();
         }
@@ -101,7 +101,7 @@ abstract class Factor
         Guard::argumentIsValidIndex($messageIndex, count($this->messages), 'messageIndex');
 
         $message = $this->messages[$messageIndex];
-        $variable = $this->messageToVariableBinding->getValue($message);
+        $variable = $this->msgToVariableBinding->getValue($message);
 
         return $this->sendMessageVariable($message, $variable);
     }
@@ -112,7 +112,7 @@ abstract class Factor
 
     protected function createVariableToMessageBindingWithMessage(Variable $variable, Message $message): Message
     {
-        $this->messageToVariableBinding->setValue($message, $variable);
+        $this->msgToVariableBinding->setValue($message, $variable);
         $this->messages[] = $message;
         $this->variables[] = $variable;
 

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;
     }
 
     /**

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/Variable.php

@@ -10,7 +10,7 @@ class Variable
 {
     private mixed $value;
 
-    public function __construct(private GaussianDistribution $prior)
+    public function __construct(private readonly GaussianDistribution $prior)
     {
         $this->resetToPrior();
     }

src/FactorGraphs/VariableFactory.php

@@ -6,20 +6,20 @@ namespace DNW\Skills\FactorGraphs;
 
 class VariableFactory
 {
-    public function __construct(private \Closure $variablePriorInitializer)
+    public function __construct(private readonly \Closure $varPriorInitializer)
     {
     }
 
     public function createBasicVariable(): Variable
     {
-        $initializer = $this->variablePriorInitializer;
+        $initializer = $this->varPriorInitializer;
 
         return new Variable($initializer());
     }
 
     public function createKeyedVariable(mixed $key): KeyedVariable
     {
-        $initializer = $this->variablePriorInitializer;
+        $initializer = $this->varPriorInitializer;
 
         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/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

@@ -55,7 +55,6 @@ class GaussianDistribution
             $this->precisionMean = $this->precision * $this->mean;
         } else {
             $this->precision = \INF;
-
             $this->precisionMean = $this->mean == 0 ? 0 : \INF;
         }
     }
@@ -175,7 +174,7 @@ class GaussianDistribution
         BasicMath::square($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)
@@ -183,22 +182,22 @@ class GaussianDistribution
         //        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
+    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;
@@ -246,7 +245,7 @@ class GaussianDistribution
 
         $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 $p): float
@@ -272,9 +271,9 @@ class GaussianDistribution
         return ($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);
     }
 }

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 ($currentColumnTransposeMatrix = 0; $currentColumnTransposeMatrix < $this->rowCount; ++$currentColumnTransposeMatrix) {
-                $transposeMatrix[$currentRowTransposeMatrix][$currentColumnTransposeMatrix] =
-                    $rowMatrixData[$currentColumnTransposeMatrix][$currentRowTransposeMatrix];
+        for ($curRowTransposeMx = 0; $curRowTransposeMx < $this->columnCount; ++$curRowTransposeMx) {
+            for ($curColTransposeMx = 0; $curColTransposeMx < $this->rowCount; ++$curColTransposeMx) {
+                $transposeMatrix[$curRowTransposeMx][$curColTransposeMx] =
+                    $rowMatrixData[$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];
-            $b = $this->matrixRowData[0][1];
-            $c = $this->matrixRowData[1][0];
-            $d = $this->matrixRowData[1][1];
+            $a = $this->getValue(0, 0);
+            $b = $this->getValue(0, 1);
+            $c = $this->getValue(1, 0);
+            $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];
-            $b = $this->matrixRowData[0][1];
-            $c = $this->matrixRowData[1][0];
-            $d = $this->matrixRowData[1][1];
+            $a = $this->getValue(0, 0);
+            $b = $this->getValue(0, 1);
+            $c = $this->getValue(1, 0);
+            $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
-        $smallestPercentage = 0.0001;
-        if ($partialPlayPercentage < $smallestPercentage) {
-            return $smallestPercentage;
+        $smallestPct = 0.0001;
+        if ($partialPlayPct < $smallestPct) {
+            return $smallestPct;
         }
 
-        return $partialPlayPercentage;
+        return $partialPlayPct;
     }
 }

src/Player.php

@@ -13,27 +13,27 @@ class Player implements ISupportPartialPlay, ISupportPartialUpdate
 
     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 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 $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 $partialPlayPct   The weight percentage to give this player when calculating a new rank.
+     * @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 $partialUpdatePercentage = self::DEFAULT_PARTIAL_UPDATE_PERCENTAGE
+        float $partialPlayPct = self::DEFAULT_PARTIAL_PLAY_PERCENTAGE,
+        float $partialUpdatePct = self::DEFAULT_PARTIAL_UPDATE_PERCENTAGE
     )
     {
-        Guard::argumentInRangeInclusive($partialPlayPercentage, 0.0, 1.0, 'partialPlayPercentage');
-        Guard::argumentInRangeInclusive($partialUpdatePercentage, 0, 1.0, 'partialUpdatePercentage');
-        $this->PartialPlayPercentage = $partialPlayPercentage;
-        $this->PartialUpdatePercentage = $partialUpdatePercentage;
+        Guard::argumentInRangeInclusive($partialPlayPct, 0.0, 1.0, 'partialPlayPercentage');
+        Guard::argumentInRangeInclusive($partialUpdatePct, 0, 1.0, 'partialUpdatePercentage');
+        $this->PartialPlayPct = $partialPlayPct;
+        $this->PartialUpdatePct = $partialUpdatePct;
     }
 
     /**
@@ -49,7 +49,7 @@ class Player implements ISupportPartialPlay, ISupportPartialUpdate
      */
     public function getPartialPlayPercentage(): float
     {
-        return $this->PartialPlayPercentage;
+        return $this->PartialPlayPct;
     }
 
     /**
@@ -57,6 +57,6 @@ class Player implements ISupportPartialPlay, ISupportPartialUpdate
      */
     public function getPartialUpdatePercentage(): float
     {
-        return $this->PartialUpdatePercentage;
+        return $this->PartialUpdatePct;
     }
 }

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/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/GaussianLikelihoodFactor.php

@@ -60,9 +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/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]
@@ -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

src/TrueSkill/Layers/IteratedTeamDifferencesInnerLayer.php

@@ -15,8 +15,8 @@ class IteratedTeamDifferencesInnerLayer extends TrueSkillFactorGraphLayer
 {
     public function __construct(
         TrueSkillFactorGraph $parentGraph,
-        private readonly TeamPerformancesToTeamPerformanceDifferencesLayer $TeamPerformancesToTeamPerformanceDifferencesLayer,
-        private readonly TeamDifferencesComparisonLayer $TeamDifferencesComparisonLayer
+        private readonly TeamPerformancesToTeamPerformanceDifferencesLayer $teamPerformancesToTeamPerformanceDifferencesLayer,
+        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->TeamDifferencesComparisonLayer->getLocalFactors()
+            $this->teamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors(),
+            $this->teamDifferencesComparisonLayer->getLocalFactors()
         );
     }
 
     public function buildLayer(): void
     {
         $inputVariablesGroups = $this->getInputVariablesGroups();
-        $this->TeamPerformancesToTeamPerformanceDifferencesLayer->setInputVariablesGroups($inputVariablesGroups);
-        $this->TeamPerformancesToTeamPerformanceDifferencesLayer->buildLayer();
+        $this->teamPerformancesToTeamPerformanceDifferencesLayer->setInputVariablesGroups($inputVariablesGroups);
+        $this->teamPerformancesToTeamPerformanceDifferencesLayer->buildLayer();
 
-        $teamDifferencesOutputVariablesGroups = $this->TeamPerformancesToTeamPerformanceDifferencesLayer->getOutputVariablesGroups();
-        $this->TeamDifferencesComparisonLayer->setInputVariablesGroups($teamDifferencesOutputVariablesGroups);
-        $this->TeamDifferencesComparisonLayer->buildLayer();
+        $teamDifferencesOutputVariablesGroups = $this->teamPerformancesToTeamPerformanceDifferencesLayer->getOutputVariablesGroups();
+        $this->teamDifferencesComparisonLayer->setInputVariablesGroups($teamDifferencesOutputVariablesGroups);
+        $this->teamDifferencesComparisonLayer->buildLayer();
     }
 
     public function createPriorSchedule(): ?ScheduleSequence
@@ -56,9 +56,9 @@ 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];
@@ -83,8 +83,8 @@ class IteratedTeamDifferencesInnerLayer extends TrueSkillFactorGraphLayer
 
     private function createTwoTeamInnerPriorLoopSchedule(): ScheduleSequence
     {
-        $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors = $this->TeamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
-        $teamDifferencesComparisonLayerLocalFactors = $this->TeamDifferencesComparisonLayer->getLocalFactors();
+        $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors = $this->teamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
+        $teamDifferencesComparisonLayerLocalFactors = $this->teamDifferencesComparisonLayer->getLocalFactors();
 
         $firstPerfToTeamDiff = $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors[0];
         $firstTeamDiffComparison = $teamDifferencesComparisonLayerLocalFactors[0];
@@ -109,13 +109,13 @@ class IteratedTeamDifferencesInnerLayer extends TrueSkillFactorGraphLayer
 
     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();
-            $teamDifferencesComparisonLayerLocalFactors = $this->TeamDifferencesComparisonLayer->getLocalFactors();
+            $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors = $this->teamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
+            $teamDifferencesComparisonLayerLocalFactors = $this->teamDifferencesComparisonLayer->getLocalFactors();
 
             $currentTeamPerfToTeamPerfDiff = $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors[$i];
             $currentTeamDiffComparison = $teamDifferencesComparisonLayerLocalFactors[$i];
@@ -151,8 +151,8 @@ class IteratedTeamDifferencesInnerLayer extends TrueSkillFactorGraphLayer
         $backwardScheduleList = [];
 
         for ($i = 0; $i < $totalTeamDifferences - 1; ++$i) {
-            $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors = $this->TeamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
-            $teamDifferencesComparisonLayerLocalFactors = $this->TeamDifferencesComparisonLayer->getLocalFactors();
+            $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors = $this->teamPerformancesToTeamPerformanceDifferencesLayer->getLocalFactors();
+            $teamDifferencesComparisonLayerLocalFactors = $this->teamDifferencesComparisonLayer->getLocalFactors();
 
             $differencesFactor = $teamPerformancesToTeamPerformanceDifferencesLayerLocalFactors[$totalTeamDifferences - 1 - $i];
             $comparisonFactor = $teamDifferencesComparisonLayerLocalFactors[$totalTeamDifferences - 1 - $i];

src/TrueSkill/Layers/PlayerPerformancesToTeamPerformancesLayer.php

@@ -27,8 +27,8 @@ class PlayerPerformancesToTeamPerformancesLayer extends TrueSkillFactorGraphLaye
             $this->addLayerFactor($newSumFactor);
 
             // REVIEW: Does it make sense to have groups of one?
-            $outputVariablesGroups = &$this->getOutputVariablesGroups();
-            $outputVariablesGroups[] = [$teamPerformance];
+            $outputVarGroups = &$this->getOutputVariablesGroups();
+            $outputVarGroups[] = [$teamPerformance];
         }
     }
 

src/TrueSkill/Layers/PlayerPriorValuesToSkillsLayer.php

@@ -34,12 +34,12 @@ class PlayerPriorValuesToSkillsLayer extends TrueSkillFactorGraphLayer
             $localCurrentTeam = $currentTeam;
             $currentTeamSkills = [];
 
-            $currentTeamAllPlayers = $localCurrentTeam->getAllPlayers();
-            foreach ($currentTeamAllPlayers as $currentTeamPlayer) {
-                $localCurrentTeamPlayer = $currentTeamPlayer;
-                $currentTeamPlayerRating = $currentTeam->getRating($localCurrentTeamPlayer);
-                $playerSkill = $this->createSkillOutputVariable($localCurrentTeamPlayer);
-                $priorFactor = $this->createPriorFactor($currentTeamPlayerRating, $playerSkill);
+            $curTeamAllPlayers = $localCurrentTeam->getAllPlayers();
+            foreach ($curTeamAllPlayers as $curTeamPlayer) {
+                $localCurTeamPlayer = $curTeamPlayer;
+                $curTeamPlayerRating = $currentTeam->getRating($localCurTeamPlayer);
+                $playerSkill = $this->createSkillOutputVariable($localCurTeamPlayer);
+                $priorFactor = $this->createPriorFactor($curTeamPlayerRating, $playerSkill);
                 $this->addLayerFactor($priorFactor);
                 $currentTeamSkills[] = $playerSkill;
             }

src/TrueSkill/Layers/PlayerSkillsToPerformancesLayer.php

@@ -15,25 +15,25 @@ class PlayerSkillsToPerformancesLayer extends TrueSkillFactorGraphLayer
 {
     public function buildLayer(): void
     {
-        $inputVariablesGroups = $this->getInputVariablesGroups();
-        $outputVariablesGroups = &$this->getOutputVariablesGroups();
+        $inputVarGroups = $this->getInputVariablesGroups();
+        $outputVarGroups = &$this->getOutputVariablesGroups();
 
-        foreach ($inputVariablesGroups as $currentTeam) {
+        foreach ($inputVarGroups as $currentTeam) {
             $currentTeamPlayerPerformances = [];
 
             /**
-             * @var Variable $playerSkillVariable
+             * @var Variable $playerSkillVar
              */
-            foreach ($currentTeam as $playerSkillVariable) {
-                $localPlayerSkillVariable = $playerSkillVariable;
-                $currentPlayer = ($localPlayerSkillVariable instanceof KeyedVariable) ? $localPlayerSkillVariable->getKey() : "";
+            foreach ($currentTeam as $playerSkillVar) {
+                $localPlayerSkillVar = $playerSkillVar;
+                $currentPlayer = ($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;
         }
     }
 

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;
 
@@ -118,9 +118,9 @@ class TrueSkillFactorGraph extends FactorGraph
         $allLayersReverse = array_reverse($this->layers);
 
         foreach ($allLayersReverse as $currentLayer) {
-            $currentPosteriorSchedule = $currentLayer->createPosteriorSchedule();
-            if ($currentPosteriorSchedule != NULL) {
-                $fullSchedule[] = $currentPosteriorSchedule;
+            $curPosteriorSchedule = $currentLayer->createPosteriorSchedule();
+            if ($curPosteriorSchedule != NULL) {
+                $fullSchedule[] = $curPosteriorSchedule;
             }
         }
 

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);
-        $denominator = GaussianDistribution::cumulativeTo($drawMargin - $teamPerformanceDifferenceAbsoluteValue)
+        $teamPerformanceDiffAbsValue = abs($teamPerformanceDiff);
+        $denominator = GaussianDistribution::cumulativeTo($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) {
-            $localSelfTeamCurrentPlayer = $selfTeamCurrentPlayer;
-            $previousPlayerRating = $selfTeam->getRating($localSelfTeamCurrentPlayer);
+        foreach ($selfTeamAllPlayers as $selfTeamCurPlayer) {
+            $localSelfTeamCurPlayer = $selfTeamCurPlayer;
+            $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/GuardTest.php

@@ -28,7 +28,9 @@ class GuardTest extends TestCase
 
     public function testargumentIsValidIndexArgumentValid(): void
     {
-        Guard::argumentIsValidIndex(5, 10, "dummy");
+        Guard::argumentIsValidIndex(0, 10, "dummy");
+        Guard::argumentIsValidIndex(1, 10, "dummy");
+        Guard::argumentIsValidIndex(9, 10, "dummy");
         $this->expectNotToPerformAssertions();
     }
 
@@ -48,7 +50,12 @@ class GuardTest extends TestCase
 
     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

@@ -7,6 +7,7 @@ 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
@@ -19,13 +20,14 @@ class HashMapTest extends TestCase
         $this->assertEquals([], $h->getAllValues());
 
 
-        $o1 = new \stdClass();
-        $o2 = new \stdClass();
+        $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));

tests/Numerics/GaussianDistributionTest.php

@@ -92,6 +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
@@ -101,6 +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
@@ -115,4 +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

@@ -22,6 +22,83 @@ use Exception;
 // 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);

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/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.
 
@@ -849,24 +847,7 @@ class TrueSkillCalculatorTests
         $team15 = new Team($player15, $gameInfo->getDefaultRating());
         $team16 = new Team($player16, $gameInfo->getDefaultRating());
 
-        $teams = [
-            $team1,
-            $team2,
-            $team3,
-            $team4,
-            $team5,
-            $team6,
-            $team7,
-            $team8,
-            $team9,
-            $team10,
-            $team11,
-            $team12,
-            $team13,
-            $team14,
-            $team15,
-            $team16
-        ];
+        $teams = [$team1, $team2, $team3, $team4, $team5, $team6, $team7, $team8, $team9, $team10, $team11, $team12, $team13, $team14, $team15, $team16];
 
         $newRatings = $calculator->calculateNewRatings(
             $gameInfo,