Returns the densities, but with a Gaussian smearing of
        std dev sigma applied.

        Args:
            sigma: Std dev of Gaussian smearing function.

        Returns:
            Gaussian-smeared densities.

def get_smeared_densities(self, sigma):
        """
        Returns the densities, but with a Gaussian smearing of
        std dev sigma applied.

        Args:
            sigma: Std dev of Gaussian smearing function.

        Returns:
            Gaussian-smeared densities.
        """

        from scipy.ndimage.filters import gaussian_filter1d
        diff = [self.frequencies[i + 1] - self.frequencies[i]
                for i in range(len(self.frequencies) - 1)]
        avgdiff = sum(diff) / len(diff)

        smeared_dens = gaussian_filter1d(self.densities, sigma / avgdiff)
        return smeared_dens