def psd(self, fftlength=None, overlap=None, window='hann',
            method=DEFAULT_FFT_METHOD, **kwargs):
        """Calculate the PSD `FrequencySeries` for this `TimeSeries`

        Parameters
        ----------
        fftlength : `float`
            number of seconds in single FFT, defaults to a single FFT
            covering the full duration

        overlap : `float`, optional
            number of seconds of overlap between FFTs, defaults to the
            recommended overlap for the given window (if given), or 0

        window : `str`, `numpy.ndarray`, optional
            window function to apply to timeseries prior to FFT,
            see :func:`scipy.signal.get_window` for details on acceptable
            formats

        method : `str`, optional
            FFT-averaging method, see *Notes* for more details

        **kwargs
            other keyword arguments are passed to the underlying
            PSD-generation method

        Returns
        -------
        psd :  `~gwpy.frequencyseries.FrequencySeries`
            a data series containing the PSD.

        Notes
        -----
        The accepted ``method`` arguments are:

        - ``'bartlett'`` : a mean average of non-overlapping periodograms
        - ``'median'`` : a median average of overlapping periodograms
        - ``'welch'`` : a mean average of overlapping periodograms
        """
        # get method
        method_func = spectral.get_method(method)

        # calculate PSD using UI method
        return spectral.psd(self, method_func, fftlength=fftlength,
                            overlap=overlap, window=window, **kwargs)
Calculate the PSD `FrequencySeries` for this `TimeSeries`

        Parameters
        ----------
        fftlength : `float`
            number of seconds in single FFT, defaults to a single FFT
            covering the full duration

        overlap : `float`, optional
            number of seconds of overlap between FFTs, defaults to the
            recommended overlap for the given window (if given), or 0

        window : `str`, `numpy.ndarray`, optional
            window function to apply to timeseries prior to FFT,
            see :func:`scipy.signal.get_window` for details on acceptable
            formats

        method : `str`, optional
            FFT-averaging method, see *Notes* for more details

        **kwargs
            other keyword arguments are passed to the underlying
            PSD-generation method

        Returns
        -------
        psd :  `~gwpy.frequencyseries.FrequencySeries`
            a data series containing the PSD.

        Notes
        -----
        The accepted ``method`` arguments are:

        - ``'bartlett'`` : a mean average of non-overlapping periodograms
        - ``'median'`` : a median average of overlapping periodograms
        - ``'welch'`` : a mean average of overlapping periodograms