Resolve "including NF uncertainties causes resulting uncertainties to be wrong"

This MR concerns a bug where including scale uncertainties (NF uncertainties) was not done correctly. Terms which should not be correlated were considered as fully correlated which leads to hugely inflated uncertainties in cutflows. The changes in this MR prevent these combinations of objects to contribute to the resulting uncertainty of the summed counter.

Closes #25 (closed)

@rgugel I think we should try and discuss any details associated with merging branches in dedicated merge requests, if for no other reason than to properly document discussion. We should also easily be able to cherry-pick the changes to other branches in the GitLab gui as well.

@dshope fair enough. This MR concerns a bug where including scale uncertainties (NF uncertainties) was not done correctly. Terms which should not be correlated were considered as fully correlated which leads to hugely inflated uncertainties in cutflows. The changes in this MR prevent these combinations of objects to contribute to the resulting uncertainty of the summed counter.

changed the description

mentioned in commit be5e1799

merged