http://www.cnblogs.com/xiangshancuizhu/archive/2011/01/04/1925276.html
http://www.cnblogs.com/nktblog/archive/2012/07/24/2606652.html
http://www.cnblogs.com/qqingmu/archive/2009/02/25/1398215.html
http://www.cnblogs.com/avril/archive/2012/09/26/2703683.html
http://www.matlabsky.com/forum.php?mod=viewthread&tid=21089