Filters.py 文件源码

def processData(self, data):
        times = data.xvals('Time')
        dt = times[1]-times[0]

        data1 = data.asarray()
        ft = np.fft.fft(data1)

        ## determine frequencies in fft data
        df = 1.0 / (len(data1) * dt)
        freqs = np.linspace(0.0, (len(ft)-1) * df, len(ft))

        ## flatten spikes at f0 and harmonics
        f0 = self.ctrls['f0'].value()
        for i in xrange(1, self.ctrls['harmonics'].value()+2):
            f = f0 * i # target frequency

            ## determine index range to check for this frequency
            ind1 = int(np.floor(f / df))
            ind2 = int(np.ceil(f / df)) + (self.ctrls['samples'].value()-1)
            if ind1 > len(ft)/2.:
                break
            mag = (abs(ft[ind1-1]) + abs(ft[ind2+1])) * 0.5
            for j in range(ind1, ind2+1):
                phase = np.angle(ft[j])   ## Must preserve the phase of each point, otherwise any transients in the trace might lead to large artifacts.
                re = mag * np.cos(phase)
                im = mag * np.sin(phase)
                ft[j] = re + im*1j
                ft[len(ft)-j] = re - im*1j

        data2 = np.fft.ifft(ft).real

        ma = metaarray.MetaArray(data2, info=data.infoCopy())
        return ma