diff --git a/src/Phpml/Exception/NormalizerException.php b/src/Phpml/Exception/NormalizerException.php
index 5c7ced1..31abfeb 100644
--- a/src/Phpml/Exception/NormalizerException.php
+++ b/src/Phpml/Exception/NormalizerException.php
@@ -21,5 +21,4 @@ class NormalizerException extends \Exception
     {
         return new self('Fit is not allowed for this preprocessor.');
     }
-
 }
diff --git a/src/Phpml/FeatureExtraction/TfIdfTransformer.php b/src/Phpml/FeatureExtraction/TfIdfTransformer.php
index 17f5b8b..1e222d2 100644
--- a/src/Phpml/FeatureExtraction/TfIdfTransformer.php
+++ b/src/Phpml/FeatureExtraction/TfIdfTransformer.php
@@ -18,7 +18,7 @@ class TfIdfTransformer implements Transformer
      */
     public function __construct(array $samples = null)
     {
-        if($samples) {
+        if ($samples) {
             $this->fit($samples);
         }
     }
diff --git a/src/Phpml/FeatureExtraction/TokenCountVectorizer.php b/src/Phpml/FeatureExtraction/TokenCountVectorizer.php
index 501263d..8d4a5ab 100644
--- a/src/Phpml/FeatureExtraction/TokenCountVectorizer.php
+++ b/src/Phpml/FeatureExtraction/TokenCountVectorizer.php
@@ -92,7 +92,7 @@ class TokenCountVectorizer implements Transformer
 
         foreach ($tokens as $token) {
             $index = $this->getTokenIndex($token);
-            if(false !== $index) {
+            if (false !== $index) {
                 $this->updateFrequency($token);
                 if (!isset($counts[$index])) {
                     $counts[$index] = 0;
diff --git a/src/Phpml/Preprocessing/Imputer.php b/src/Phpml/Preprocessing/Imputer.php
index 424efa4..012bb79 100644
--- a/src/Phpml/Preprocessing/Imputer.php
+++ b/src/Phpml/Preprocessing/Imputer.php
@@ -27,14 +27,14 @@ class Imputer implements Preprocessor
     private $axis;
 
     /**
-     * @var $samples
+     * @var
      */
     private $samples;
 
     /**
-     * @param mixed    $missingValue
-     * @param Strategy $strategy
-     * @param int      $axis
+     * @param mixed      $missingValue
+     * @param Strategy   $strategy
+     * @param int        $axis
      * @param array|null $samples
      */
     public function __construct($missingValue = null, Strategy $strategy, int $axis = self::AXIS_COLUMN, array $samples = [])
diff --git a/src/Phpml/Transformer.php b/src/Phpml/Transformer.php
index 1accdda..f7ddd81 100644
--- a/src/Phpml/Transformer.php
+++ b/src/Phpml/Transformer.php
@@ -6,7 +6,6 @@ namespace Phpml;
 
 interface Transformer
 {
-
     /**
      * @param array $samples
      */
diff --git a/tests/Phpml/FeatureExtraction/TokenCountVectorizerTest.php b/tests/Phpml/FeatureExtraction/TokenCountVectorizerTest.php
index cf22b5c..3a5f7fe 100644
--- a/tests/Phpml/FeatureExtraction/TokenCountVectorizerTest.php
+++ b/tests/Phpml/FeatureExtraction/TokenCountVectorizerTest.php
@@ -78,7 +78,6 @@ class TokenCountVectorizerTest extends \PHPUnit_Framework_TestCase
         $vectorizer->transform($samples);
         $this->assertEquals($tokensCounts, $samples);
 
-
         // word at least once in all samples
         $samples = [
             'Lorem ipsum dolor sit amet',
diff --git a/tests/Phpml/Preprocessing/ImputerTest.php b/tests/Phpml/Preprocessing/ImputerTest.php
index fce195b..c607510 100644
--- a/tests/Phpml/Preprocessing/ImputerTest.php
+++ b/tests/Phpml/Preprocessing/ImputerTest.php
@@ -172,5 +172,4 @@ class ImputerTest extends \PHPUnit_Framework_TestCase
 
         $this->assertEquals($imputeData, $data, '', $delta = 0.01);
     }
-
 }
diff --git a/tests/Phpml/Preprocessing/NormalizerTest.php b/tests/Phpml/Preprocessing/NormalizerTest.php
index d01e62c..f0e21c9 100644
--- a/tests/Phpml/Preprocessing/NormalizerTest.php
+++ b/tests/Phpml/Preprocessing/NormalizerTest.php
@@ -79,5 +79,4 @@ class NormalizerTest extends \PHPUnit_Framework_TestCase
 
         $this->assertEquals($normalized, $samples, '', $delta = 0.01);
     }
-
 }