Telco 20200424

Date

Friday, 24 April, 15:00 CET (+0100)

Hangout Link: https://plus.google.com/hangouts/_/j72qwlvegiojjpt3a36pfhow5ua

Agenda

• Issue #748: Mixed use of NXreflections and NXmx telco
• Issue #765: NXcanSAS “radiation” duplicates NXsource “type”
• Issue #762: [NXtomo] Need user flags
• Issue #757: How to add extra attributes and avoid conflicts with NeXus in the future?

Minutes

Present: BW, AB, FA, HG, HB, MK, PJ, PC

NIAC

• NOBUGS registration is split into separate days for the code camp
• linking not yet
• spacing for SD is fine
• need to make sure teleconferencing is adequate

Pull Request #767

• AB notes PR #767 is ready for final review.
• PJ notes that travis-ci reports a failure (reST syntax encoded within XML).

Issue #748

• NXreflections describes diffraction spots in a tabular format, having evolved from historical practice of attributing and recording diffraction spots from film-based photographs.
• it is a base class and not an appdef (currently)
• Both versions (base class and AppDef) have use cases.
• An Appdef should be written that has NXreflections as a major component so that it can be used together with NXmx AB brings up related Pull Request #767

Issue #765

• best to mark radiation as deprecated
• PJ to discuss with canSAS people

Issue #762

• user def keys should be negative
• extra (or subgroup of fields) fields (NXnotes) needed to describe user def keys
  • Need stadardised name for description
• any new positive key should be NIAC approved

AB asks MK: base classes can’t be a subentry?

• subentries must be AppDef
• entries can also be AppDef

Issue #757

• HB suggests doing what the PDB community does and have a list of registered prefixes
• starting with an underscore didn’t work out for PDB
• NIAC should grant power for approving prefix registration
• BW suggests prefixes be in uppercase to make them obvious to human readers
• PJ suggests prefixes be followed by an underscore
• PJ will post new issue with proposal for the NIAC

Any Other Business

• PC asks NXuser for a group of users
  • MK suggests using multiple instances of NXuser
• PC ask: is there a way to give numerical precision?
  • should be applicable to any general field
  • Outside of current scope - someone needs to propose a method - perhaps as an attribute
• HG asks: How has NeXus been approaching ontologies and mapping metadata betwen formats
  • NeXus predates much of the current academic interest in ontologies
  • PJ suggests talking to a group at the ALS
  • PJ asks if there is a general Ontology that NeXus can fit within
  • HG says that ontologies tend to sit next to each other as peers, rather than under an umbrella ontology
• PJ points to the index of the NeXus definitions as a starting point to mapping the NeXus ontology
  • HG will create new GitHub issue for a published NeXus ontology
  • PJ proposed using information from the manual’s index as a starting point
  • PJ noted that various items of NeXus structure (group, field, attribute) are automatically indexed
  • MK noted that position in hierarchy is important since some terms (such as name) have multiple meanings
  • ontology should include
    • NeXus class path to specify hierachy position
    • documentation content from the NXDL for each item listed

Next telco: Mid May, using a poll in the same manner as previously.