Hi geologyhero
In the code for this script (available here) you can see at the bottom that different uncertainties are used for different columns. Here is the relevant part of the code:
The highligthed uncert_types shows which uncertainty type is reported for which column. For some results both the internal and propagated uncertainties are reported (any that have both 2 and 3 in the uncert_types list). A description of the different uncertainty types is below:
Uncert_type: Description
1: 1 RSE(%). Calculated as 0.5 * 100 * result.uncertaintyAs2SE()/result.value()
2: 2 SE (abs)
3: 2SE (abs, propagated uncertainty, as described here)
You can see that there are a few columns that don't use this notation (e.g. Pb206/204). In this case, either an uncertainty is not reported (e.g. the concordance percentage conc_pct), or the 1RSE (%) is reported (e.g. pb206_204 and pb208_206)
I hope that helps. Please let me know if you have any questions.
Kind regards,
Bence