说明：  关于实现低通滤波器的小程序,是matlab编程的,只不过装在word文档里,只要贴到matlab的m文件里,即能实现功能.对初学者有很好的借鉴意义.
(on the realization of the low-pass filter small procedures, Matlab programming. just loaded word in the document, as long as Matlab affixed to the document m, It is able to achieve functional. for beginners have a good reference.)