已知传递函数怎么用matlab画群延时特性曲线?答:用grpdelay Group delay of adaptive, discrete-time, and multirate filters Syntax [gd,w] = grpdelay(ha)[gd,w] = grpdelay(ha,n)[gd,w] = grpdelay(...,f)grpdelay(ha)[gd,w] = grpdelay(hd)[gd,w] = grpdelay(hd,n)[gd,w] = grpdelay(...,f)grpdelay(hd)[gd,w] = ...