Uploading new code from https://github.com/dhotson/classifier-php

Updated with PSR4 class and composer for autoloading packagist.

Author: Stéphane Bauland

README.md

@@ -3,5 +3,5 @@ A PHP Bayesian classifier algorithm library.
 
 ### Installation
 ```php
-composer require roomoot/classifier
+composer require rookmoot/classifier
 ```

composer.json

@@ -0,0 +1,17 @@
+{
+    "name": "rookmoot/classifier",
+    "type": "library",
+    "description": "A PHP Bayesian classifier algorithm library.",
+    "keywords": ["Bayes", "Bayesian", "classifier", "algorithm"],
+    "homepage": "http://www.diatelys.fr",
+    "license": "BSD",
+    "authors": [
+        {
+            "name": "Stéphane Bauland",
+            "email": "[email protected]"
+        }
+    ],
+    "autoload": {
+        "psr-4": {"Classify\\": "src/"}
+    }
+}

src/Classify.php

@@ -0,0 +1,211 @@
+<?php
+
+namespace Classify;
+
+/**
+ * PHP version of Ruby Bayes classifier library
+ * @see http://github.com/xaviershay/classifier
+ */
+class Classify
+{
+	private $_categories;
+	private $_totalWords;
+
+	/**
+	 * The class can be created with one or more categories, each of which will be
+	 * initialized and given a training method. E.g.,
+	 *	  $b = new Bayes('Interesting', 'Uninteresting', 'Spam')
+	 */
+	public function __construct()
+	{
+		$categories = func_get_args();
+
+		$this->_totalWords = 0;
+
+		$this->_categories = array();
+		foreach ($categories as $category)
+		{
+			$this->_categories[$category] = array();
+		}
+	}
+
+	/**
+	 * Provides a general training method for all categories specified in Bayes#new
+	 * For example:
+	 *	 $b = new Bayes('this', 'that', 'the_other')
+	 *	 $b->train('this', 'This text')
+	 *	 $b->train('that', 'That text')
+	 *	 $b->train('the_other', 'The other text')
+	 */
+	public function train($category, $text)
+	{
+		foreach ($this->_wordArray($text) as $word => $count)
+		{
+			if (!isset($this->_categories[$category][$word]))
+				$this->_categories[$category][$word] = 0;
+
+			$this->_categories[$category][$word] += $count;
+
+			$this->_totalWords += $count;
+		}
+	}
+
+	/**
+	 * Returns the scores in each category the provided +text+. E.g.,
+	 *	$b->classifications("I hate bad words and you")
+	 *	=>  {"Uninteresting" => -12.6997928013932, "Interesting" => -18.4206807439524}
+	 * The largest of these scores (the one closest to 0) is the one picked out by classify()
+	 */
+	public function classifications($text)
+	{
+		$score = array();
+
+		foreach ($this->_categories as $category => $categoryWords)
+		{
+			$score[$category] = 0.0;
+			$total = array_sum(array_values($categoryWords));
+
+			foreach ($this->_wordArray($text) as $word => $count)
+			{
+				$s = isset($categoryWords[$word]) ? $categoryWords[$word] : 0.1;
+				$score[$category] += log($s / $total);
+			}
+		}
+
+		return $score;
+	}
+
+	/**
+	 * Returns the classification of the provided +text+, which is one of the
+	 * categories given in the initializer. E.g.,
+	 *	$b->classify("I hate bad words and you")
+	 *	=>  'Uninteresting'
+	 */
+	public function classify($text)
+	{
+		$a = $this->classifications($text);
+		arsort($a);
+		return array_shift(array_keys($a));
+	}
+
+	// ----
+
+	/**
+	 * Return an array of strings => ints. Each word in the string is stemmed,
+	 * and indexes to its frequency in the document.
+	 */
+	private function _wordArray($word)
+	{
+		return $this->_wordArrayForWords(
+			array_merge(
+				preg_split('/\s+/', preg_replace('/[^\w\s]/','', $word)),
+				preg_split('/\s+/', preg_replace('/[\w]/',' ', $word))));
+	}
+
+	private function _wordArrayForWords($words)
+	{
+		$d = array();
+
+		foreach ($words as $word)
+		{
+			if (preg_match('/[\w]+/',$word)) $word = strtolower($word);
+			$key = Stemmer::Stem($word);
+
+			if (preg_match('/[^\w]/',$word)
+				|| !in_array($word, self::$CORPUS_SKIP_WORDS)
+				&& strlen($word) > 2)
+			{
+				if (!isset($d[$key]))
+					$d[$key] = 0;
+
+				$d[$key] += 1;
+			}
+		}
+
+		return $d;
+	}
+
+	private static $CORPUS_SKIP_WORDS = array(
+		"a",
+		"again",
+		"all",
+		"along",
+		"are",
+		"also",
+		"an",
+		"and",
+		"as",
+		"at",
+		"but",
+		"by",
+		"came",
+		"can",
+		"cant",
+		"couldnt",
+		"did",
+		"didn",
+		"didnt",
+		"do",
+		"doesnt",
+		"dont",
+		"ever",
+		"first",
+		"from",
+		"have",
+		"her",
+		"here",
+		"him",
+		"how",
+		"i",
+		"if",
+		"in",
+		"into",
+		"is",
+		"isnt",
+		"it",
+		"itll",
+		"just",
+		"last",
+		"least",
+		"like",
+		"most",
+		"my",
+		"new",
+		"no",
+		"not",
+		"now",
+		"of",
+		"on",
+		"or",
+		"should",
+		"sinc",
+		"so",
+		"some",
+		"th",
+		"than",
+		"this",
+		"that",
+		"the",
+		"their",
+		"then",
+		"those",
+		"to",
+		"told",
+		"too",
+		"true",
+		"try",
+		"until",
+		"url",
+		"us",
+		"were",
+		"when",
+		"whether",
+		"while",
+		"with",
+		"within",
+		"yes",
+		"you",
+		"youll",
+		);
+}
+