Access binning information #286
Description
For corrections based on bins (e.g. muon/egamma scale factors, jet energy scale, ...), precision analyses need to decorrelate the statistical uncertainty component between bins. However, a single stat variation of the correction is typically provided, merging all bins together.
Since correctionlib doesn't provide binning information, the bin boundaries currently have to be hard-coded separately by the analyses. This is very likely to go out-of-sync.
A possible solution in the current framework is to ask for stat_bin1... stat_bin50 variations in the JSON, but I think it's not realistic to ask all the POGs to do this for the benefit of a handful of analyses.
It would therefore be great if we could inspect corrections to retrieve a binning or bin index.