M000025.html
2.05 KB
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<title>entropy (Mirimiri::Document)</title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<link rel="stylesheet" href="../../.././rdoc-style.css" type="text/css" media="screen" />
</head>
<body class="standalone-code">
<pre><span class="ruby-comment cmt"># File lib/mirimiri/document.rb, line 81</span>
<span class="ruby-keyword kw">def</span> <span class="ruby-identifier">entropy</span>(<span class="ruby-identifier">s</span>)
<span class="ruby-identifier">en</span> = <span class="ruby-value">0</span><span class="ruby-value">.0</span>
<span class="ruby-identifier">counts</span> = <span class="ruby-keyword kw">self</span>.<span class="ruby-identifier">count_words</span>
<span class="ruby-identifier">s</span>.<span class="ruby-identifier">split</span>.<span class="ruby-identifier">each</span> <span class="ruby-keyword kw">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">w</span><span class="ruby-operator">|</span>
<span class="ruby-identifier">p_wi</span> = <span class="ruby-identifier">counts</span>[<span class="ruby-identifier">w</span>].<span class="ruby-identifier">to_f</span><span class="ruby-operator">/</span><span class="ruby-ivar">@words</span>.<span class="ruby-identifier">count</span>.<span class="ruby-identifier">to_f</span>
<span class="ruby-identifier">en</span> <span class="ruby-operator">+=</span> <span class="ruby-identifier">p_wi</span><span class="ruby-operator">*</span><span class="ruby-constant">Math</span>.<span class="ruby-identifier">log2</span>(<span class="ruby-identifier">p_wi</span>)
<span class="ruby-keyword kw">end</span>
<span class="ruby-identifier">en</span> <span class="ruby-operator">*=</span> <span class="ruby-value">-1</span>
<span class="ruby-identifier">en</span>
<span class="ruby-keyword kw">end</span></pre>
</body>
</html>