PHP Classes

File: index.php

Recommend this page to a friend!
  Classes of Michele Andreoli   Fast Fourier Transform   index.php   Download  
File: index.php
Role: Example script
Content type: text/plain
Description: Index
Class: Fast Fourier Transform
Compute the Fast Fourier Transform of sampled data
Author: By
Last change: update email
Date: 10 years ago
Size: 1,521 bytes
 

Contents

Class file image Download
<?php
/**
 * @author Michele Andreoli <michi.andreoli[at]gmail.com>
 * @name index.php
 * @version 0.1 updated 07-05-2010
 * @license http://opensource.org/licenses/gpl-license-php GNU Public License
 * @package FFT
 */
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <title>Fast Fourier Transform, FFT</title>
    </head>
    <body>
            <?php
               
require_once 'FFT.class.php';
               
               
// Define a generic function
               
$f = array();
                for (
$i = 0; $i < 256; $i++) {
                    if ((
$i >= 0 && $i <= 8) || ($i >= 248 && $i <= 255))
                       
$f[$i] = 1;
                    else
                       
$f[$i] = 0;
                }
               
               
$fft = new FFT(256);
               
               
// Calculate the FFT of the function $f
               
$w = $fft->fft($f);
               
                echo
"<h1 style=\"font: bold 14px verdana;\">FFT: </h1>";
                for (
$i = 0; $i < $fft->getDim(); $i++)
                    echo
"<p style=\"font: normal 10px verdana;\"><b>".$i."</b> (".$w[$i]->getReal().", ".$w[$i]->getImag().")</p>";
               
               
// Calculate the inverse FFT of the function $w
               
$w = $fft->ifft($w);
               
                echo
"<br/><h1 style=\"font: bold 14px verdana;\">FFT inverse:</h1>";
                for (
$i = 0; $i < $fft->getDim(); $i++)
                    echo
"<p style=\"font: normal 10px verdana;\"><b>".$i."</b> (".$w[$i]->getReal().")</p>";
           
?>
</body>
</html>