#?-*-?coding:?utf-8?-*-
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Created?on?Sun?Aug?26?23:42:40?2018

@author:?Administrator
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import?numpy?as?np
import?matplotlib.pyplot?as?plt
import?scipy.signal?as?signal

def?halfBand（cutofffsripple1ripple2）:
????“““
????cutoff:?通帶截止頻率;
????fs:?采樣頻率;
????ripple1:通帶最大波紋（+dB）;
????ripple2:阻帶最小衰減（+dB）。
????“““
????if?ripple1????????ripple=ripple2
????else:
????????ripple=ripple1#取最嚴格的限制
????#wc=2*np.pi*cutoff/fs
????f_a=0.5*fs-cutoff#阻帶截止頻率，半帶濾波器特點，f_c+f_a=pi
????numtaps?