def walk(self, N=64, freq_base=A2, freq_max=C8,  start=0, end=None, each=True, combine=False, twin=0.020, thop=0.010, gamma=10, cof=4000, tinteg=0.020, tconst=0.008):
        ''''''
        samplerate = self.audio.samplerate
        tinv = 1./samplerate
        pwin = self.poisson(tinteg, tinv, tconst)
        #pwin = self.rectangle(tinteg, tinv)
        pwin /= len(pwin)   # normalization
        lenpre = len(pwin)-1
        ypre = np.zeros((lenpre,N))
        #
        cstep = int(np.ceil(thop*samplerate))
        cwin = int(np.ceil(twin*samplerate))
        Y = np.zeros((0,N))
        if combine:
            assert 0 < twin <= thop
            assert 0 < cstep <= cwin
        #
        for y in super(Y5, self).walk(N,freq_base,freq_max,start,end,each=False,combine=False,gamma=gamma,cof=cof):
            ym = np.append(ypre, y, 0)
            ypre = ym[-lenpre:]
            for i,yband in enumerate(ym.T):
                y[...,i] = np.sqrt(np.convolve(np.square(yband), pwin, 'valid'))
            if not combine:
                if each:
                    for v in y: yield v
                else: yield y
            else:
                Y = np.append(Y, y, 0)
                while Y.shape[0] >= cwin:
                    wf, Y = Y[:cwin], Y[cstep:]
                    yield np.sqrt(np.mean(np.square(wf), 0))
        if combine and Y.shape[0] > 0:
            yield np.sqrt(np.mean(np.square(Y), 0))
dataset/ETHPy150Open dongying/dear/dear/spectrum/auditory.py/Y5.walk/swapped operands of `<=`