transforms.py 文件源码

def apply_ellip_filter(self, data, order, cutoff, btype):
        ripple = 3
        attenuation = 50
        cutoff /= self.nyq
        b, a = iirfilter(N=order, Wn=cutoff, rp=ripple, rs=attenuation,
                         btype=btype, ftype='ellip')
        return lfilter(b, a, data, axis=0)