DIALS core meeting 2026-02-12

Previous Actions

• ND Investigate getting psana tests running on the DIALS xfel-regression testing
• ND: Move dials.diamond.ac.uk to a redirect to dials.github.io

Agenda

Sphinx-Design extra dependency

• Added in https://github.com/dials/dials/pull/3093
• Merged because important for tutorial pages to be usable, apologies for lack of warning

“Array not Writable”

• Issue related to pandas 3.0 change to read-only arrays with Copy-on-Write semantics, means that all extracted numpy arrays are now read-only: https://github.com/dials/dials/issues/3086.
• JBE fixed temporarily with pandas pin https://github.com/dials/dials/issues/3086
• Root of issue fixed with https://github.com/cctbx/dxtbx/pull/876

Other CI Issues

• Installers failing on our internal CI machines. Down to launch logic in https://github.com/dials/dials/blob/e91f5f66368ec546b160ccfd2fbd30b2926a65de/installer/create_installer.py#L36-L52 that prefers python2.7 if available - looks like conda-pack switched to requiring python 3.
• Probably easiest way for now is to just use python/python3 and remove the fallbacks.
• 31/36 xfel-regression tests failing with errors like “/bin/sh: 1: cctbx.xfel.time_varying_refinement: not found”. So some build issue there? Help please?

dials.github.io

• Mac installer link broken
• ND to look into, currently macos tests failing causing the development build not to be deployed
• https://github.com/cctbx/cctbx_project/issues/1119
• Fixed in Feburary 2026 release 2026.1
• ND: Make sure this fixes issue

Metrics

• 2025-09-25 - dxtbx-side merged in, nothing yet in DIALS side to push it into the mtz history https://github.com/cctbx/dxtbx/pull/816
• Needs to be work to put in on DIALS side
• Work to do:
  • Need to package history into MTZ, but MTZ history not the right place. Decided MTZ-appendix is the right place to put this in, but work not started yet
  • Aaron has offered Yang’s skills as his work should cover this area
  • Write integrate and scale history to MTZ #2924
  • David to dig relevant information out
• MTZ Appendix: Some controversy
  • Phenix/DIALS not included in discussions
  • Fundamental technological issues
    • Mixing MTZ/CIF
• Gemmi supports
• AB met with BP/DGW/Oleg/Dorothy and talking about MTZ appendix issue
  • Conclusion: Nobody completely happy, AB to approach Clemens and get conversation going
• Dan Paley found issue with profiling and MTZ appendix https://github.com/cctbx/dxtbx/pull/867
  • Agreed looks reasonable
  • Requested David to have a look

AOAOB

• Probably table for new year
  • It is now new year
• Hamburg: imageset, sequences, laziness so it works on 100,000 image HDF5 files
• Did some work in a branch to get stills_process to use imagesequences
• Nick did some work to eliminate need for check_format
• All of this is in branches that have not been revisited
• Discussion about still goniometer dogma

ImageSequence vs ImageSet

• Marko is working on an NXmx-like format class for SerialED, where the beam position changes each image
• It seems not possible to use ImageSequence for this, as it does not allow different models per image. Is this correct?
• ImageSet works, but import and viewing images is much slower
• Is there a long term plan to converge to just one of these classes, with all performance and feature issues fixed?
• Suggestion to look at DMcD properties table
• Discussion about serialization/deserialization overhead, brief discussion of using another form e.g. hdf5 or sqlite (for Experiment Lists).
• Discussion of existing uses of mixin inheritance

APS Workshop

• This did not get support from APS => not happening (APS UM workshop, )
• ~~GW had conversation about expanding workshop scope. Was half-day, thought maybe a full day - scope expanded to e.g. serial processing ~~
• APS User meeting: May 4th-8th 2026 two half-days of DIALS workshop probably
• Some travel funding available, potentially from outside US
• Proposal submitted, no reply yet, probably not before Christmas
• CCP4 workshop is happening APS
• AB says RAPIdata also approached us about DIALS workshops there - GW believes AB/DP covering

Other

• Webinars: GW did one yesterday for NSLSII, requests for a couple more…
  • ED, xia2.ssx and stills_process requests
  • JBE happy to approach
  • Chat to DGW about ED
  • Dan nominated by AB to prepare for stills_process
  • GW to email, coordinate
  • GW Emailed Vivian, JBE looped in and aware.
  • Discussion ongoing, people on top of
• ND to investigate effort required for installer build issue resolution
  • Investigated basic, infrastructure still fails to identify macOS arm, still need to proceed with conda-based installer plan
• xfel regression testing of https://github.com/dials/dials/pull/3062 (cosym performance changes) JBE asking for help please. Also somewhat unrelated, regular failing of CI jobs due to http download errors?
  • We should turn off regression tests
  • Maybe explore gitlab LFS as it works well for xfel-regression
• IUCR: AB putting schedule together for DIALS workshop, wondering who is going to be attending, for scheduling speakers. 8am-Noon
  • Need answers by Feb 15th

AOB

Next meeting

Thursday, February 26th, 4pm (GMT), 8am (PST), 10am (CST)