说明：  方根幅值是计算裕度指标与波性指标的必要部分，本文件将其独立做成了一个子VI，方便labview程序调用。希望对小伙伴有所帮助！
(The root mean square amplitude is a necessary part of the margin index and the wave index. This document makes it a sub VI, which is convenient for LabVIEW program call. Hope to help small partners!)