Firedrake meeting 2025 12 09

Date and time 2025-12-09 1600 UTC+1

Action Items

1. Pick Chair and Minuter (LC to pick -> PB)
2. ALL: (ongoing) triage the open issues and confirm if they are indeed still open (and perhaps provide labels)
3. ALL: do things with SV's branches
4. DH: Email to Andreas to have 2 (+ others!!!) loopy PRs merged TODO: FIND OUT WHICH PRS THESE ARE
5. DH: Talk to GregVernon about PR#2116.
6. CW: More testing configurations (minutes)

Minutes

Present: DH, JHC, CW, LC, PB, IM, AC

Apologies:

Data Assimilation hackathon at RAL (Spring 2026)

DH: organized by CoSeC fellow Jemima Tabeart (TU Eindhoven)

CW: we should add this to the Firedrake calendar

JHC: Covariance operators and noise generation #4716

Autoregressive covariance operators for a) generating correlated noise and b) weighting norms in optimisation problems. (Changes suggested)

Includes noise generation code from #3799 (Changes suggested)

PB: we should automate BrokenElement(VectorElement) -> VectorElement(BrokenElement) in finat.ufl

PB: once could a CholeskyFactor node to Slate to avoid the parloop (not for this PR)

DH: The VOM mass matrix is always the identity, this should be special case.

JHC: add demos in the Spring hackathon.

CW: Comm fixes (quite a big conceptual change)

https://github.com/firedrakeproject/firedrake/pull/4766 (approved)

DH: we should comment on pytest-order when we merge this

LC: interpolate a two-form

https://github.com/firedrakeproject/firedrake/pull/4770 (approved)

Merge PRs

In-person meeting in Oxford (20 Jan 2026)

Date of next meeting

1600 UTC 2025-12-16