机器学习之主成分分析 推荐博文:http://blog.codinglabs.org/articles/pca-tutorial.html 推荐博文:http://www.cnblogs.com/jerrylead/archive/2011/04/18/2020209.html(上) 推荐博文:http://www.cnblogs.com/jerrylead/archive/2011/04/18/2020216.html(下)