Tracking issue for PHYSLITE schema

[nikoladze]

This is to track the TODO list/open questions for the PHYSLITE schema for nanoevents

• Port ElementLink handling to awkward dask fix: Daskify Elementlinks in PHYSLITE schema #872
• Add a test for a simple selection procedure involving several collections
• Continue with global index forms or to use a different approach? Use eventindex instead of global index form for PHYSLITE schema #541
• Complete the list of mixin classes and add important methods
• Make Records of Unions instead of Unions of Records for the cases with links into multiple collections? (maybe better try not to make unions at all, e.g. for truth collection create a homogeneous record)
• Find out why ak.where triggers materialization of a few (but not all) columns (probably different situation now with dask)
• Silence warnings or add a filter function to be passed to TBranch.iteritems
• Add EventInfo collection and check if there are more non-jagged collections fix: allow for collections that contain non-jagged arrays in PHYSLITE schema #888
• Zip the HLT collection (this changed in newer PHYSLITE versions, see next point)
• Find out how trigger info/matching works and how we make it work in columnar analysis
• Find a way to load the hash to branchname mapping from the MetaData tree (or calculate hash manually) (maybe we better hardcode targets for cases where there is only a single one and make a special treatment for truth collection)
• Try out what is/isn't working with newer versions of PHYSLITE
• Some collections (e.g. TruthMuons) have fiels that can't be zipped (empty lists for some events, so can't use common offsets). How to handle this? Have a list of collections not to zip? Don't zip anything at all?

[lgray]

Seems stale.