php实现根据词频生成tag云的方法

这篇文章主要介绍了php实现根据词频生成tag云的方法,涉及php分析与操作字符串以及标签云的生成技巧,具有一定参考借鉴价值,需要的朋友可以参考下。

本文实例讲述了php实现根据词频生成tag云的方法,分享给大家供大家参考,具体如下:

这里给定一段文本,分析文本的词频分布,生成tag云

  1. <?php
  2. /**
  3. * Tag cloud demo based on word frequency
  4. * @author: unknown
  5. * @since: 2007-02-27
  6. */
  7. // Store frequency of words in an array
  8. $freqData = array();
  9. // Random words
  10. $lorem = "Lorem ipsum dolor sit amet, consectetuer adipiscing elit.
  11. Phasellus vestibulum ullamcorper tortor. Aenean quis lacus quis neque
  12. adipiscing ultricies. Pellentesque tincidunt ligula vitae nibh ornare
  13. pharetra. Proin dignissim tortor. Donec et ipsum nec tellus gravida
  14. tempor. Aliquam ullamcorper purus vel felis. Praesent faucibus.
  15. Curabitur porta. Nulla in lorem quis mi lacinia fringilla. Integer
  16. adipiscing mi quis felis. Pellentesque habitant morbi tristique senectus
  17. et netus et malesuada fames ac turpis egestas. Quisque sagittis ante in
  18. arcu. Sed libero enim, venenatis sit amet, vestibulum at, porttitor id,
  19. neque. Vestibulum ornare semper erat. Sed tincidunt nibh et massa. Cras
  20. sed diam. Quisque blandit enim.
  21. Sed nonummy. Aenean mollis turpis quis enim. Nam massa nulla, varius
  22. molestie, aliquet et, feugiat eget, nisi. Sed mollis, leo ut pretium
  23. placerat, nibh turpis egestas ipsum, sed aliquam neque enim in risus.
  24. Nullam nisl. Sed tincidunt leo quis tellus. Mauris non lorem. Aenean
  25. tristique justo at arcu. Fusce et lorem. Nam sodales. Mauris condimentum
  26. diam. Nam commodo. Cum sociis natoque penatibus et magnis dis parturient
  27. montes, nascetur ridiculus mus. Cras ac risus. Proin et dolor laoreet mi
  28. gravida sodales. Duis bibendum, ipsum posuere egestas posuere, dui lacus
  29. feugiat turpis, id tincidunt urna est sit amet est. Cras eu sem.
  30. ";
  31. // Get individual words and build a frequency table
  32. foreach( str_word_count( $lorem, 1 ) as $word )
  33. {
  34. // For each word found in the frequency table,
  35. //increment its value by one
  36. array_key_exists($word,$freqData)?$freqData[$word]++:$freqData[$word]=0;
  37. }
  38. // ==============================================================
  39. // = Function to actually generate the cloud from provided data =
  40. // ==============================================================
  41. function getCloud($data = array(), $minFontSize = 12, $maxFontSize = 30)
  42. {
  43. $minimumCount = min( array_values( $data ) );
  44. $maximumCount = max( array_values( $data ) );
  45. $spread = $maximumCount - $minimumCount;
  46. $cloudHTML = '';
  47. $cloudTags = array();
  48. $spread == 0 && $spread = 1;
  49. foreach( $data as $tag => $count )
  50. {
  51. $size = $minFontSize + ( $count - $minimumCount )
  52. * ( $maxFontSize - $minFontSize ) / $spread;
  53. $cloudTags[] = '<a . floor( $size ) . 'px'
  54. . '" class="tag_cloud" href="http://www.google.com/search?q='
  55. . $tag
  56. . '" title="\'' . $tag . '\' returned a count of ' . $count
  57. . '">'
  58. . htmlspecialchars( stripslashes( $tag ) ) . '</a>';
  59. }
  60. return join( "\n", $cloudTags ) . "\n";
  61. }
  62. ?>
  63. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
  64. "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
  65. <html xmlns="http://www.w3.org/1999/xhtml">
  66. <head>
  67. <title>Tag Cloud Demo</title>
  68. <style type="text/css" media="screen">
  69. /*<![CDATA[*/
  70. .tag_cloud { padding: 3px; text-decoration: none; }
  71. .tag_cloud:link { color: #81d601; }
  72. .tag_cloud:visited { color: #019c05; }
  73. .tag_cloud:hover { color: #ffffff; background: #69da03; }
  74. .tag_cloud:active { color: #ffffff; background: #ACFC65; }
  75. /*]]>*/
  76. </style>
  77. </head>
  78. <body>
  79. <h1>Sample Tag Cloud</h1>
  80. <div >
  81. <?php echo getCloud( $freqData ) ?>
  82. </div>
  83. </body>
  84. </html>