函数：滑动均值滤波--analog signals 优点：可重用，代码量小，数据实时无间断 缺点：边沿平滑，不适合突变检测 要求：使用前，必须先初始化 案例：sum的初值为基准值；buff[]不能大于sum-Function: sliding mean filter- analog signals advantages: reusability, a small amount of code and data in real time without interruption D