def moving_average(self, sampling_period,
                       window_size=None,
                       start=None, end=None,
                       placement='center',
                       pandas=False):
        """Averaging over regular intervals

        """
        start, end, mask = self._check_boundaries(start, end)

        # default to sampling_period if not given
        if window_size is None:
            window_size = sampling_period

        sampling_period = \
            self._check_regularization(start, end, sampling_period)

        # convert to datetime if the times are datetimes
        half_window = float(window_size) / 2
        full_window = float(window_size)
        if isinstance(start, datetime.datetime):
            half_window = datetime.timedelta(seconds=half_window)
            full_window = datetime.timedelta(seconds=full_window)

        result = []
        current_time = start
        while current_time <= end:

            if placement == 'center':
                window_start = current_time - half_window
                window_end = current_time + half_window
            elif placement == 'left':
                window_start = current_time
                window_end = current_time + full_window
            elif placement == 'right':
                window_start = current_time - full_window
                window_end = current_time
            else:
                msg = 'unknown placement "{}"'.format(placement)
                raise ValueError(msg)

            # calculate mean over window and add (t, v) tuple to list
            mean = self.mean(window_start, window_end)
            result.append((current_time, mean))

            current_time += sampling_period

        # convert to pandas Series if pandas=True
        if pandas:

            try:
                import pandas as pd
            except ImportError:
                msg = "can't have pandas=True if pandas is not installed"
                raise ImportError(msg)

            result = pd.Series(
                [v for t, v in result],
                index=[t for t, v in result],
            )

        return result