pid_encoder_decoder.py 文件源码

def __init__(self, threshold_freq, order=2, design='cheby1'):
        """
        :param threshold_freq: Threshold frequency to filter out, as a fraction of sampling freq.  E.g. 0.1
        """
        self.b, self.a = \
            butter(N=order, Wn=threshold_freq, btype='low') if design == 'butter' else \
            cheby1(N=order, rp=0.1, Wn=threshold_freq, btype='low') if design == 'cheby1' else \
            bad_value(design)
        self.filter_state = lfilter_zi(b=self.b, a=self.a)