Viewing file:  Statistics.php (7.04 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
<?php
/* vim: set expandtab tabstop=4 softtabstop=4 shiftwidth=4: */
// +----------------------------------------------------------------------+
// | PHP version 4 |
// +----------------------------------------------------------------------+
// | Copyright (c) 1997-2002 The PHP Group |
// +----------------------------------------------------------------------+
// | This source file is subject to version 2.0 of the PHP license, |
// | that is bundled with this package in the file LICENSE, and is |
// | available at through the world-wide-web at |
// | http://www.php.net/license/2_02.txt. |
// | If you did not receive a copy of the PHP license and are unable to |
// | obtain it through the world-wide-web, please send a note to |
// | license@php.net so we can mail you a copy immediately. |
// +----------------------------------------------------------------------+
// | Author: George Schlossnagle <george@omniti.com> |
// +----------------------------------------------------------------------+
//
// $Id: Statistics.php 251907 2008-02-01 06:52:59Z cweiske $
require_once "Text/Word.php";
/**
* Text_Statistics calculates some basic readability metrics on a
* block of text. The number of words, the number of sentences,
* and the number of total syllables is counted. These statistics
* can be used to calculate the Flesch score for a sentence, which
* is a number (usually between 0 and 100) that represents the
* readability of the text. A basic breakdown of scores is:
*
* 90 to 100 5th grade
* 80 to 90 6th grade
* 70 to 80 7th grade
* 60 to 70 8th and 9th grade
* 50 to 60 10th to 12th grade (high school)
* 30 to 50 college
* 0 to 30 college graduate
*
* More info can be read up on at
* http://www.mang.canterbury.ac.nz/courseinfo/AcademicWriting/Flesch.htm
*
* require 'Text/Statistics.php';
* $block = Text_Statistics($sometext);
* $block->flesch; // returns flesch score for $sometext
*
* see the unit tests for additional examples.
*
* @package Text_Statistics
* @author George Schlossnagle <george@omniti.com>
*/
class Text_Statistics
{
/**
* The document text.
*
* @access public
* @var string
*/
var $text = '';
/**
* The number of syllables in the document.
*
* @var int
* @access public
*/
var $numSyllables = 0;
/**
* The number of words in the document.
*
* @var int
* @access public
*/
var $numWords = 0;
/**
* The number of unique words in the document.
*
* @var int
* @access public
*/
var $uniqWords = 0;
/**
* The number of sentences in the document.
*
* @var int
* @access public
*/
var $numSentences = 0;
/**
* The Flesch score of the document.
* It is FALSE if there were no words in the document.
*
* @var float
* @access public
*/
var $flesch = 0;
/**
* Flesch-Kincaid grade level
* It is FALSE if there were no words in the document.
*
* @var float
* @access public
*/
var $gradeLevel = 0;
/**
* Some abbreviations we should expand. This list could/should
* be much larger.
*
* @var array
* @access protected
*/
var $_abbreviations = array('/Mr\./' => 'Mister',
'/Mrs\./i' => 'Misses', // Phonetic
'/etc\./i' => 'etcetera',
'/Dr\./i' => 'Doctor',
'/Jr\./i' => 'Junior',
'/Sr\./i' => 'Senior',
);
/**
* List of all words that have been found already.
* @var array
*/
var $_uniques = array();
/**
* Constructor.
*
* @param string
* @access public
*/
function Text_Statistics($block)
{
$this->text = trim($block);
$this->_analyze();
$this->text = null;
}
/**
* Returns the character frequencies.
*
* @return array of frequencies, where the index is the ASCII byte char value
* @access public
* @author Jesus M. Castagnetto <jmcastagnetto@php.net>
*/
function getCharFreq() {
return $this->_charFreq;
}
/**
* Returns the number of paragaphs.
* Paragraphs are defined as chunks of text separated by
* and empty line.
*
* @return long
* @access public
* @author Jesus M. Castagnetto <jmcastagnetto@php.net>
*/
function getNumParagraphs() {
return $this->_numParas;
}
/**
* Compute statistics for the document object.
*
* @access protected
*/
function _analyze()
{
// char frequencies
$this->_charFreq = count_chars($this->text);
$this->text = preg_replace(array_keys($this->_abbreviations),
array_values($this->_abbreviations),
$this->text);
preg_match_all('/[.!?](\s|$)/', $this->text, $matches);
$this->numSentences = count($matches[0]);
$lines = explode("\n", $this->text);
// Set ourselves as 'out of text block to start
$intext = 0;
foreach( $lines as $line ) {
// A paragraph is when we enter a text line
// after a line that was all whitespace
if(preg_match("/\S/", $line)) {
if($intext == 0) {
$this->_numParas++;
$intext = 1;
}
}
else {
$intext = 0;
}
$this->_analyze_line($line);
}
if ($this->numSentences == 0) {
$this->numSentences = 1;
}
if ($this->numWords == 0) {
$this->flesch = false;
$this->gradeLevel = false;
return;
}
$wordsPerSent = $this->numWords / $this->numSentences;
$syllablesPerWord = $this->numSyllables / $this->numWords;
$this->flesch = 206.835
- 1.015 * $wordsPerSent
- 84.6 * $syllablesPerWord;
$this->gradeLevel = 0.39 * $wordsPerSent
+ 11.8 * $syllablesPerWord
- 15.59;
}
/**
* Helper function, computes statistics on a given line.
*
* @param string
* @access protected
*/
function _analyze_line($line)
{
// expand abbreviations for counting syllables
preg_match_all("/\b(\w[\w'-]*)\b/", $line, $words);
foreach( $words[1] as $word ) {
$w_obj = new Text_Word($word);
$this->numSyllables += $w_obj->numSyllables();
$this->numWords++;
if(!isset($this->_uniques[$word])) {
$this->_uniques[$word] = 1;
} else {
$this->uniqWords++;
}
}
}
}
?>
|