vqinitcenter.html
来自「一个关于数据聚类和模式识别的程序,在生物化学,化学中因该都可以用到.希望对大家有」· HTML 代码 · 共 78 行
HTML
78 行
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd"><html><head> <title>Description of vqInitCenter</title> <meta name="keywords" content="vqInitCenter"> <meta name="description" content="vqInitCenter: Find initial centers for VQ or k-means"> <meta http-equiv="Content-Type" content="text/html; charset=big5"> <meta name="generator" content="m2html © 2003 Guillaume Flandin"> <meta name="robots" content="index, follow"> <link type="text/css" rel="stylesheet" href="../m2html.css"></head><body><a name="_top"></a><div><a href="../index.html">Home</a> > <a href="index.html">dcpr</a> > vqInitCenter.m</div><!--<table width="100%"><tr><td align="left"><a href="../index.html"><img alt="<" border="0" src="../left.png"> Master index</a></td><td align="right"><a href="index.html">Index for dcpr <img alt=">" border="0" src="../right.png"></a></td></tr></table>--><h1>vqInitCenter</h1><h2><a name="_name"></a>PURPOSE <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2><div class="box"><strong>vqInitCenter: Find initial centers for VQ or k-means</strong></div><h2><a name="_synopsis"></a>SYNOPSIS <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2><div class="box"><strong>function center = vqInitCenter(data, clusterNum, method) </strong></div><h2><a name="_description"></a>DESCRIPTION <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2><div class="fragment"><pre class="comment"> vqInitCenter: Find initial centers for VQ or k-means
Usage: center = vqInitCenter(data, clusterNum, method)</pre></div><!-- crossreference --><h2><a name="_cross"></a>CROSS-REFERENCE INFORMATION <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2>This function calls:<ul style="list-style-image:url(../matlabicon.gif)"></ul>This function is called by:<ul style="list-style-image:url(../matlabicon.gif)"><li><a href="vqKmeans.html" class="code" title="function [center, U, distortion, allCenter] = vqKmeans(data, clusterNum, plotOpt)">vqKmeans</a> vqKmeans: Vector quantization using K-means clustering (Forgy's batch-mode method)</li></ul><!-- crossreference --><h2><a name="_source"></a>SOURCE CODE <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2><div class="fragment"><pre>0001 <a name="_sub0" href="#_subfunctions" class="code">function center = vqInitCenter(data, clusterNum, method)</a>0002 <span class="comment">% vqInitCenter: Find initial centers for VQ or k-means</span>0003 <span class="comment">% Usage: center = vqInitCenter(data, clusterNum, method)</span>0004 0005 <span class="comment">% Roger Jang, 20041204</span>0006 0007 <span class="keyword">if</span> nargin<3; method=1; <span class="keyword">end</span>0008 <span class="keyword">switch</span> method0009 <span class="keyword">case</span> 10010 <span class="comment">% ====== Method 1: Randomly pick clusterNum data points as cluster centers</span>0011 dataNum = size(data, 2);0012 temp = randperm(dataNum);0013 center = data(:, temp(1:clusterNum));0014 <span class="keyword">case</span> 20015 <span class="comment">% ====== Method 2: Choose clusterNum data points closest to mean vector</span>0016 meanVec = mean(data, 2);0017 distMat = pairwiseSqrDistance(meanVec, data);0018 [minDist, colIndex] = sort(distMat);0019 center = data(:, colIndex(1:clusterNum));0020 <span class="keyword">case</span> 30021 <span class="comment">% ====== Method 3: Choose clusterNum data points furthest to the mean vector</span>0022 meanVec = mean(data, 2);0023 distMat = pairwiseSqrDistance(meanVec, data);0024 [minDist, colIndex] = sort(-distMat);0025 center = data(:, colIndex(1:clusterNum));0026 <span class="keyword">case</span> 40027 <span class="comment">% ====== Method 4: Choose first few data as the centers</span>0028 center = data(:, 1:clusterNum);0029 <span class="keyword">otherwise</span>0030 error(<span class="string">'Unknown method!'</span>);0031 <span class="keyword">end</span></pre></div><hr><address>Generated on Thu 30-Oct-2008 12:53:56 by <strong><a href="http://www.artefact.tk/software/matlab/m2html/">m2html</a></strong> © 2003</address></body></html>⌨️ 快捷键说明
复制代码Ctrl + C
搜索代码Ctrl + F
全屏模式F11
增大字号Ctrl + =
减小字号Ctrl + -
显示快捷键?