def to_timeseries(self, delta_t=None):
        """ Return the Fourier transform of this time series.

        Note that this assumes even length time series!
        
        Parameters
        ----------
        delta_t : {None, float}, optional
            The time resolution of the returned series. By default the 
        resolution is determined by length and delta_f of this frequency 
        series.
        
        Returns
        -------        
        TimeSeries: 
            The inverse fourier transform of this frequency series. 
        """
        from pycbc.fft import ifft
        from pycbc.types import TimeSeries, real_same_precision_as
        nat_delta_t =  1.0 / ((len(self)-1)*2) / self.delta_f
        if not delta_t:
            delta_t = nat_delta_t

        # add 0.5 to round integer
        tlen  = int(1.0 / self.delta_f / delta_t + 0.5)
        flen = int(tlen / 2 + 1)
        
        if flen < len(self):
            raise ValueError("The value of delta_t (%s) would be "
                             "undersampled. Maximum delta_t "
                             "is %s." % (delta_t, nat_delta_t))
        if not delta_t:
            tmp = self
        else:
            tmp = FrequencySeries(zeros(flen, dtype=self.dtype), 
                             delta_f=self.delta_f, epoch=self.epoch)
            tmp[:len(self)] = self[:]
        
        f = TimeSeries(zeros(tlen, 
                           dtype=real_same_precision_as(self)),
                           delta_t=delta_t)
        ifft(tmp, f)
        return f
Return the Fourier transform of this time series.

        Note that this assumes even length time series!
        
        Parameters
        ----------
        delta_t : {None, float}, optional
            The time resolution of the returned series. By default the 
        resolution is determined by length and delta_f of this frequency 
        series.
        
        Returns
        -------        
        TimeSeries: 
            The inverse fourier transform of this frequency series.