MDL-65769 lib: update PHP-ML to 0.8.0

lib/mlbackend/php/phpml/src/Phpml/Pipeline.php

@@ -7,9 +7,9 @@ namespace Phpml;
 class Pipeline implements Estimator
 {
     /**
-     * @var array|Transformer[]
+     * @var Transformer[]
      */
-    private $transformers;
+    private $transformers = [];
 
     /**
      * @var Estimator
@@ -17,8 +17,7 @@ class Pipeline implements Estimator
     private $estimator;
 
     /**
-     * @param array|Transformer[] $transformers
-     * @param Estimator           $estimator
+     * @param Transformer[] $transformers
      */
     public function __construct(array $transformers, Estimator $estimator)
     {
@@ -29,52 +28,40 @@ class Pipeline implements Estimator
         $this->estimator = $estimator;
     }
 
-    /**
-     * @param Transformer $transformer
-     */
-    public function addTransformer(Transformer $transformer)
+    public function addTransformer(Transformer $transformer): void
     {
         $this->transformers[] = $transformer;
     }
 
-    /**
-     * @param Estimator $estimator
-     */
-    public function setEstimator(Estimator $estimator)
+    public function setEstimator(Estimator $estimator): void
     {
         $this->estimator = $estimator;
     }
 
     /**
-     * @return array|Transformer[]
+     * @return Transformer[]
      */
-    public function getTransformers()
+    public function getTransformers(): array
     {
         return $this->transformers;
     }
 
-    /**
-     * @return Estimator
-     */
-    public function getEstimator()
+    public function getEstimator(): Estimator
     {
         return $this->estimator;
     }
 
-    /**
-     * @param array $samples
-     * @param array $targets
-     */
-    public function train(array $samples, array $targets)
+    public function train(array $samples, array $targets): void
     {
-        $this->fitTransformers($samples);
-        $this->transformSamples($samples);
+        foreach ($this->transformers as $transformer) {
+            $transformer->fit($samples, $targets);
+            $transformer->transform($samples);
+        }
+
         $this->estimator->train($samples, $targets);
     }
 
     /**
-     * @param array $samples
-     *
      * @return mixed
      */
     public function predict(array $samples)
@@ -84,20 +71,7 @@ class Pipeline implements Estimator
         return $this->estimator->predict($samples);
     }
 
-    /**
-     * @param array $samples
-     */
-    private function fitTransformers(array &$samples)
-    {
-        foreach ($this->transformers as $transformer) {
-            $transformer->fit($samples);
-        }
-    }
-
-    /**
-     * @param array $samples
-     */
-    private function transformSamples(array &$samples)
+    private function transformSamples(array &$samples): void
     {
         foreach ($this->transformers as $transformer) {
             $transformer->transform($samples);