def moving_frequency(self, data_frame):
        """
            This method returns moving frequency

            :param data_frame: the data frame
            :type data_frame: pandas.DataFrame
            :return diff_mov_freq: frequency
            :rtype diff_mov_freq: float

        """
        f = []
        for i in range(0, (data_frame.td[-1].astype('int') - self.window)):
            f.append(sum(data_frame.action_type[(data_frame.td >= i) & (data_frame.td < (i + self.window))] == 1) /
                     float(self.window))

        diff_mov_freq = (np.array(f[1:-1]) - np.array(f[0:-2])) / np.array(f[0:-2])

        duration = math.ceil(data_frame.td[-1])

        return diff_mov_freq, duration