minor refactoring of Algorithm class

Author: bdelespierre

src/Algorithm.php

@@ -14,9 +14,11 @@
 class Algorithm implements AlgorithmInterface
 {
     private InitializationSchemeInterface $initScheme;
-    /** @var array<callable> */
-    private array $iterationCallbacks = [];
 
+    /**
+     * @var array<callable>
+     */
+    private array $iterationCallbacks = [];
 
     public function __construct(InitializationSchemeInterface $initScheme)
     {
@@ -46,7 +48,19 @@ public function clusterize(PointCollectionInterface $points, int $nbClusters): C
         return $clusters;
     }
 
-    protected function iterate(ClusterCollectionInterface $clusters): bool
+    protected function getDistanceBetween(PointInterface $pointA, PointInterface $pointB): float
+    {
+        return Math::euclideanDist($pointA->getCoordinates(), $pointB->getCoordinates());
+    }
+
+    protected function findCentroid(PointCollectionInterface $points): PointInterface
+    {
+        return new Point($points->getSpace(), Math::centroid(
+            array_map(fn (PointInterface $point) => $point->getCoordinates(), iterator_to_array($points))
+        ));
+    }
+
+    private function iterate(ClusterCollectionInterface $clusters): bool
     {
         /** @var \SplObjectStorage<ClusterInterface, null> */
         $changed = new \SplObjectStorage();
@@ -78,7 +92,7 @@ protected function iterate(ClusterCollectionInterface $clusters): bool
         return count($changed) > 0;
     }
 
-    protected function getClosestCluster(ClusterCollectionInterface $clusters, PointInterface $point): ClusterInterface
+    private function getClosestCluster(ClusterCollectionInterface $clusters, PointInterface $point): ClusterInterface
     {
         $min = null;
         $closest = null;
@@ -96,18 +110,6 @@ protected function getClosestCluster(ClusterCollectionInterface $clusters, Point
         return $closest;
     }
 
-    protected function getDistanceBetween(PointInterface $pointA, PointInterface $pointB): float
-    {
-        return Math::euclideanDist($pointA->getCoordinates(), $pointB->getCoordinates());
-    }
-
-    protected function findCentroid(PointCollectionInterface $points): PointInterface
-    {
-        return new Point($points->getSpace(), Math::centroid(
-            array_map(fn ($point) => $point->getCoordinates(), iterator_to_array($points))
-        ));
-    }
-
     protected function invokeIterationCallbacks(ClusterCollectionInterface $clusters): void
     {
         foreach ($this->iterationCallbacks as $callback) {

tests/Unit/AlgorithmTest.php

@@ -40,6 +40,9 @@ public function tearDown(): void
         Mockery::close();
     }
 
+    // ------------------------------------------------------------------------
+    // tests
+
     /**
      * @dataProvider clusterizeDataProvider
      * @covers ::__construct
@@ -102,44 +105,6 @@ public function testClusterize(
         }
     }
 
-    /**
-     * @return array<mixed>
-     */
-    public function clusterizeDataProvider(): array
-    {
-        return [
-            'one dimension, 3 clusters, 5 points per cluster' => [
-                'dimension' => 1,
-                'expected' => [
-                    [-50],
-                    [0],
-                    [50],
-                ],
-                'initialClusterCentroids' => [
-                    [-10],
-                    [0],
-                    [10]
-                ],
-                'nbPointsPerCentroid' => 5,
-            ],
-
-            'two dimensions, 3 clusters, 50 points per cluster' => [
-                'dimension' => 2,
-                'expected' => [
-                    [20, 10],
-                    [40, 20],
-                    [60, 15],
-                ],
-                'initialClusterCentroids' => [
-                    [12, 10],
-                    [33, 20],
-                    [60, 10],
-                ],
-                'nbPointsPerCentroid' => 50,
-            ],
-        ];
-    }
-
     /**
      * @covers ::__construct
      * @covers ::clusterize
@@ -198,6 +163,50 @@ function (AlgorithmInterface $algo, ClusterCollectionInterface $cluster) use (&$
         $this->assertTrue($callbackCalled);
     }
 
+    // ------------------------------------------------------------------------
+    // data-providers
+
+    /**
+     * @return array<mixed>
+     */
+    public function clusterizeDataProvider(): array
+    {
+        return [
+            'one dimension, 3 clusters, 5 points per cluster' => [
+                'dimension' => 1,
+                'expected' => [
+                    [-50],
+                    [0],
+                    [50],
+                ],
+                'initialClusterCentroids' => [
+                    [-10],
+                    [0],
+                    [10]
+                ],
+                'nbPointsPerCentroid' => 5,
+            ],
+
+            'two dimensions, 3 clusters, 50 points per cluster' => [
+                'dimension' => 2,
+                'expected' => [
+                    [20, 10],
+                    [40, 20],
+                    [60, 15],
+                ],
+                'initialClusterCentroids' => [
+                    [12, 10],
+                    [33, 20],
+                    [60, 10],
+                ],
+                'nbPointsPerCentroid' => 50,
+            ],
+        ];
+    }
+
+    // ------------------------------------------------------------------------
+    // helpers
+
     /**
      * @param array<array<float>> $centroids
      * @param int<0, max> $nbPointsPerCentroid