def source_sum_err(self):
        """
        The uncertainty of `~photutils.SourceProperties.source_sum`,
        propagated from the input ``error`` array.

        ``source_sum_err`` is the quadrature sum of the total errors
        over the non-masked pixels within the source segment:

        .. math:: \\Delta F = \\sqrt{\\sum_{i \\in S}
                  \\sigma_{\\mathrm{tot}, i}^2}

        where :math:`\\Delta F` is ``source_sum_err``,
        :math:`\\sigma_{\\mathrm{tot, i}}` are the pixel-wise total
        errors, and :math:`S` are the non-masked pixels in the source
        segment.

        Pixel values that are masked in the input ``data``, including
        any non-finite pixel values (i.e. NaN, infs) that are
        automatically masked, are also masked in the error array.
        """

        if self._error is not None:
            if self._is_completely_masked:
                return np.nan * self._error_unit  # table output needs unit
            else:
                return np.sqrt(np.sum(self._error_values ** 2))
        else:
            return None
def source_sum_err ( self ) : if self . _error is not None : if self . _is_completely_masked : return np . nan * self . _error_unit else : return np . sqrt ( np . sum ( self . _error_values ** 2 ) ) else : return None
The uncertainty of `~photutils.SourceProperties.source_sum`,
        propagated from the input ``error`` array.

        ``source_sum_err`` is the quadrature sum of the total errors
        over the non-masked pixels within the source segment:

        .. math:: \\Delta F = \\sqrt{\\sum_{i \\in S}
                  \\sigma_{\\mathrm{tot}, i}^2}

        where :math:`\\Delta F` is ``source_sum_err``,
        :math:`\\sigma_{\\mathrm{tot, i}}` are the pixel-wise total
        errors, and :math:`S` are the non-masked pixels in the source
        segment.

        Pixel values that are masked in the input ``data``, including
        any non-finite pixel values (i.e. NaN, infs) that are
        automatically masked, are also masked in the error array.