ShowTrace.py 文件源码

def butterLP(self):
        #===== parameter =====
        coefficients = self.trendLine()
        axis = str(self.axis_combobox.currentText())
        N=10
        time_interval = 0.007
        sample_rate = int(1/time_interval)
        Nquist_freq = 0.5 * sample_rate
        Wn = float(self.filtbutter_lp_slider.value()) / 1430.0

        #===== input =====
        if axis[0] =='a':
            input_signal = self.acc_normalize(self.raw_data[axis])
        elif axis[0]=='g':
            input_signal = self.gyro_normalize(self.raw_data[axis])
        elif axis[0]=='m':
            input_signal = self.raw_data[axis]

        #===== caculation area =====
        b, a = signal.butter(N, Wn, 'low')
        #d, c = signal.bessel(N, Wn, 'low')

        butter_lp_signal = signal.filtfilt(b, a, input_signal)


        #===== output =====
        raw_a, raw_v, raw_s = self.another_integral(input_signal)
        butter_lp_a, butter_lp_v, butter_lp_s = self.another_integral(butter_lp_signal)  #butter_lp_signal
        #bessel_lp_a, bessel_lp_v, bessel_lp_s = self.basic_basic_integral(bessel_lp_signal)
        print "Max: " + str(max(butter_lp_s)) + "; Min: " + str(min(butter_lp_s))

        #===== raw vs filt =====
        plt.title(axis)
        plt.subplot(311)
        plt.grid(True)
        plt.plot(raw_a, "blue", label="raw_a")
        plt.plot(butter_lp_a, "red", label="butter_lp_a")
        plt.legend(loc=2, fontsize = 'medium')

        plt.subplot(312)
        plt.grid(True)
        plt.plot(raw_v, "blue", label="raw_a")
        plt.plot(butter_lp_v, "red", label="butter_lp_v")
        plt.legend(loc=2, fontsize = 'medium')

        plt.subplot(313)
        plt.grid(True)
        plt.plot(raw_s, "blue", label="raw_a")
        plt.plot(butter_lp_s, "red", label="butter_lp_s")
        plt.legend(loc=2, fontsize = 'medium')


        plt.show()

        self.filtbutter_lp_slider.setFocus()