From e7d27801503136cd4450bbc3a8014ef13595f5ba Mon Sep 17 00:00:00 2001
From: Arkadiusz Kondas <arkadiusz.kondas@gmail.com>
Date: Fri, 8 Apr 2016 22:25:15 +0200
Subject: [PATCH] classifier predict array of samples or one sample

---
 src/Phpml/Classifier/Classifier.php           |  4 ++--
 src/Phpml/Classifier/KNearestNeighbors.php    | 21 ++++++++++++++++++-
 src/Phpml/Classifier/NaiveBayes.php           |  4 ++--
 .../Classifier/KNearestNeighborsTest.php      | 15 +++++++++++++
 4 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/src/Phpml/Classifier/Classifier.php b/src/Phpml/Classifier/Classifier.php
index 6fad67a..90250a9 100644
--- a/src/Phpml/Classifier/Classifier.php
+++ b/src/Phpml/Classifier/Classifier.php
@@ -13,9 +13,9 @@ interface Classifier
     public function train(array $samples, array $labels);
 
     /**
-     * @param array $sample
+     * @param array $samples
      *
      * @return mixed
      */
-    public function predict(array $sample);
+    public function predict(array $samples);
 }
diff --git a/src/Phpml/Classifier/KNearestNeighbors.php b/src/Phpml/Classifier/KNearestNeighbors.php
index 5a998d3..53c66b0 100644
--- a/src/Phpml/Classifier/KNearestNeighbors.php
+++ b/src/Phpml/Classifier/KNearestNeighbors.php
@@ -43,12 +43,31 @@ class KNearestNeighbors implements Classifier
         $this->labels = $labels;
     }
 
+    /**
+     * @param array $samples
+     *
+     * @return mixed
+     */
+    public function predict(array $samples)
+    {
+        if(!is_array($samples[0])) {
+            $predicted = $this->predictSample($samples);
+        } else {
+            $predicted = [];
+            foreach ($samples as $index => $sample) {
+                $predicted[$index] = $this->predictSample($sample);
+            }
+        }
+
+        return $predicted;
+    }
+
     /**
      * @param array $sample
      *
      * @return mixed
      */
-    public function predict(array $sample)
+    private function predictSample(array $sample)
     {
         $distances = $this->kNeighborsDistances($sample);
 
diff --git a/src/Phpml/Classifier/NaiveBayes.php b/src/Phpml/Classifier/NaiveBayes.php
index c1cc902..7324d79 100644
--- a/src/Phpml/Classifier/NaiveBayes.php
+++ b/src/Phpml/Classifier/NaiveBayes.php
@@ -15,11 +15,11 @@ class NaiveBayes implements Classifier
     }
 
     /**
-     * @param array $sample
+     * @param array $samples
      *
      * @return mixed
      */
-    public function predict(array $sample)
+    public function predict(array $samples)
     {
     }
 }
diff --git a/tests/Phpml/Classifier/KNearestNeighborsTest.php b/tests/Phpml/Classifier/KNearestNeighborsTest.php
index 2786ade..06ae42f 100644
--- a/tests/Phpml/Classifier/KNearestNeighborsTest.php
+++ b/tests/Phpml/Classifier/KNearestNeighborsTest.php
@@ -26,4 +26,19 @@ class KNearestNeighborsTest extends \PHPUnit_Framework_TestCase
         $this->assertEquals('a', $classifier->predict([1, 5]));
         $this->assertEquals('a', $classifier->predict([3, 10]));
     }
+
+    public function testPredictArrayOfSamples()
+    {
+        $trainSamples = [[1, 3], [1, 4], [2, 4], [3, 1], [4, 1], [4, 2]];
+        $trainLabels = ['a', 'a', 'a', 'b', 'b', 'b'];
+
+        $testSamples = [[3, 2], [5, 1], [4, 3], [4, -5], [2, 3], [1, 2], [1, 5], [3, 10]];
+        $testLabels = ['b', 'b', 'b', 'b', 'a', 'a', 'a', 'a',];
+
+        $classifier = new KNearestNeighbors();
+        $classifier->train($trainSamples, $trainLabels);
+        $predicted = $classifier->predict($testSamples);
+
+        $this->assertEquals($testLabels, $predicted);
+    }
 }