---
name: DIALS core meeting 2021-10-07
tags: core meeting
---

# DIALS core meeting 2021-10-07

[](https://hackmd.io/-tthy9xPTmaFh78MiumHzA)

## Previous Actions

- [ ] "Contiguous Nexus" [`cctbx/dxtbx#356`](https://github.com/cctbx/dxtbx/pull/356)
- [ ] Non-draft state is pending checks against issues @dwpaley raised, and checking for non-contiguous cases [[prev](https://dials.github.io/kb/core/20210715#contiguous-nexus-pr)]
- [ ] dxtbx `src/` layout [[prev](https://dials.github.io/kb/core/20210715#src-layout-for-dxtbx)]
- [ ] Nick: Ask cctbxbb if anyone has knowledge or experience of re-export of dispatchers on windows
- [ ] This is a higher priority now - David feeling pain of missing
- [ ] Also, seeing related errors "in the wild" e.g. [`cctbx/dxtbx#434`](https://github.com/cctbx/dxtbx/pull/434)
- [ ] Removal of DataBlock [[prev](https://dials.github.io/kb/core/20210909#datablock), [prev](https://dials.github.io/kb/core/20210826#removal-of-datablock)]
- [ ] **Nick:** More visible deprecationwarning
- [ ] Impact assessment to see what/who is affected
- [ ] Other repositories - stuff like, iota, prime, ls49, labelit, labelit-regression, xfel-regression, lunus, uc_metrics gitlab/cctbx*, phenix and phenix_regression (phenix.image_viewer)
- DXTBX/pycbf [[prev](https://dials.github.io/kb/core/20210826#cbflib-conda-forge-packagepycbf)]
- Outstanding: [`dxtbx#368`](https://github.com/cctbx/dxtbx/pull/368) for optional cbflib/_adaptbx .
* [ ] ND: conda-forge pycbf: Make new release to use dials-data directly for tests
* [ ] Last status: one `labelit`/`labelit_regression` test still doesn't pass
* All except one labelit tests are now working. On NKS todo list to fix.
* Progress on CBFlib 0.9.7?
- [ ] Nonconventional P1 indexing [[prev](https://dials.github.io/kb/core/20210923#nonconventional-p1-indexing)]
- [ ] Possible numeric instabilities remaining in e.g. `minimum_cell`
- [ ] **RG:** Going to look into this at some point
- [ ] Deterministic Experiment Identifiers [[prev](https://dials.github.io/kb/core/20210923#deterministic-experiment-identifiers)]
- [ ] **Aaron:** Change `dials.stills_process` to default to composite mode and not write experiment files
- [ ] **GW/Aaron**: Organise another meeting to go over ["load before heat death"](https://github.com/cctbx/dxtbx/pull/118) PR and reasons why, solutions etc

## Agenda

### LTS Python 3.7 supporting DIALS 3.7 branch

- CCP4, PHENIX likely to be stuck on Python 3.7 longer than we would like
- LTS branch from 2021 allows support
- 1 year?
- General: should we make LTS branch Jan every year
- Yes: Most people seem happy with this
- Graeme offered at a last resort to manage DIALS 3.8 releases beyond 3.8.4

### ImageSet/ImageSetData memory usage

- [`cctbx/dxtbx#438`](https://github.com/cctbx/dxtbx/pull/438)
- Described PR and associated other branch
- GW: Sounds similar to the problems we solved before. Worth spending some time going through "Load before heat death" PR and what those calls were for?
- Aaron: Spend some more time looking at ImageSequence code. After that would like to have a joint meeting to go over the changes

### Removal of DataBlock

- 2020 ls49 repo for paper uses datablocks

## Deferred to next meeting

### Nonconventional P1 indexing
- ([prev](https://dials.github.io/kb/core/20210923#nonconventional-p1-indexing), [prev](https://dials.github.io/kb/core/20210909#nonconventional-p1-indexing))
- Problem with P1 indexing not being returned in user-specified setting/order
- Issue at [`dials/dials#1878`](https://github.com/dials/dials/issues/1878)
- PR to fix: [`dials/dials#1880`](https://github.com/dials/dials/pull/1880)

### Deterministic Experiment Identifiers

- ([Previous dicussion](https://dials.github.io/kb/core/20210923#deterministic-experiment-identifiers), original PR: [`dials/dials#1864`](https://github.com/dials/dials/pull/1864))
- Previously discussed reasons for request and what data was trying to be tracked
- discussed how `ImageSequence` might work around the exact problems

### Next meeting
Thursday, October 21st, 4pm UK (BST), 8am PDT.