diff --git a/src/Phpml/Dataset/ArrayDataset.php b/src/Phpml/Dataset/ArrayDataset.php
index b2e09b7..580df0a 100644
--- a/src/Phpml/Dataset/ArrayDataset.php
+++ b/src/Phpml/Dataset/ArrayDataset.php
@@ -11,12 +11,12 @@ class ArrayDataset implements Dataset
     /**
      * @var array
      */
-    private $samples = [];
+    protected $samples = [];
 
     /**
      * @var array
      */
-    private $labels = [];
+    protected $labels = [];
 
     /**
      * @param array $samples
diff --git a/src/Phpml/Dataset/CsvDataset.php b/src/Phpml/Dataset/CsvDataset.php
index c21ac97..de540c9 100644
--- a/src/Phpml/Dataset/CsvDataset.php
+++ b/src/Phpml/Dataset/CsvDataset.php
@@ -6,7 +6,7 @@ namespace Phpml\Dataset;
 
 use Phpml\Exception\DatasetException;
 
-abstract class CsvDataset implements Dataset
+class CsvDataset extends ArrayDataset
 {
     /**
      * @var string
@@ -14,19 +14,12 @@ abstract class CsvDataset implements Dataset
     protected $filepath;
 
     /**
-     * @var array
+     * @param string|null $filepath
+     *
+     * @throws DatasetException
      */
-    private $samples = [];
-
-    /**
-     * @var array
-     */
-    private $labels = [];
-
-    public function __construct()
+    public function __construct(string $filepath = null)
     {
-        $filepath = dirname(__FILE__).'/../../../data/'.$this->filepath;
-
         if (!file_exists($filepath)) {
             throw DatasetException::missingFile(basename($filepath));
         }
@@ -46,20 +39,4 @@ abstract class CsvDataset implements Dataset
             throw DatasetException::cantOpenFile(basename($filepath));
         }
     }
-
-    /**
-     * @return array
-     */
-    public function getSamples(): array
-    {
-        return $this->samples;
-    }
-
-    /**
-     * @return array
-     */
-    public function getLabels(): array
-    {
-        return $this->labels;
-    }
 }
diff --git a/src/Phpml/Dataset/Demo/Iris.php b/src/Phpml/Dataset/Demo/Iris.php
index d544a55..5a4789e 100644
--- a/src/Phpml/Dataset/Demo/Iris.php
+++ b/src/Phpml/Dataset/Demo/Iris.php
@@ -15,7 +15,11 @@ use Phpml\Dataset\CsvDataset;
 class Iris extends CsvDataset
 {
     /**
-     * @var string
+     * @param string|null $filepath
      */
-    protected $filepath = 'iris.csv';
+    public function __construct(string $filepath = null)
+    {
+        $filepath = dirname(__FILE__).'/../../../../data/iris.csv';
+        parent::__construct($filepath);
+    }
 }