fix: aa.Array2D NameError in welcome.py (and audit other workspaces)

[Jammy2211]

Overview

autolens_workspace/welcome.py crashes with NameError: name 'aa' is not defined at line 109. The script imports autolens as al but references aa.Array2D — a stale leftover from when arrays were built via autoarray. This issue tracks fixing that bug and auditing welcome.py and start_here.py across the other workspaces (autogalaxy_workspace, autofit_workspace, HowToLens, HowToGalaxy, HowToFit) for any similar breakages.

Plan

• Fix the known aa.Array2D → al.Array2D bug in autolens_workspace/welcome.py (lines 109 and 112). autolens re-exports Array2D, so the one-character swap is the correct fix.
• Run welcome.py and start_here.py non-interactively in each of the six workspaces and capture tracebacks for any other bugs.
• Fix any further bugs discovered during the runs, scoped narrowly to whatever the tracebacks reveal — no opportunistic refactors.
• Re-run all six pairs after the fixes and confirm clean exits.

Detailed implementation plan

Affected Repositories

• autolens_workspace (primary)
• autogalaxy_workspace
• autofit_workspace
• HowToLens
• HowToGalaxy
• HowToFit

Work Classification

Workspace

Branch Survey

Repository	Current Branch	Dirty?
./autolens_workspace	main	clean
./autogalaxy_workspace	main	clean
./autofit_workspace	main	clean
./HowToLens	main	clean
./HowToGalaxy	main	clean
./HowToFit	main	clean

Suggested branch: feature/welcome-start-here-fixes
Worktree root: ~/Code/PyAutoLabs-wt/welcome-start-here-fixes/ (created later by /start_workspace)

No conflicts with active tasks. Recent branches claude/add-contents-sections-main (autolens) and notebooks-update-2026-04-28 (autogalaxy) are unrelated.

Implementation Steps

1. Fix the known aa. bug. In autolens_workspace/welcome.py, replace aa.Array2D with al.Array2D on lines 109 and 112. Grep audit across the six welcome.py files confirmed this is the only aa. reference.

2. Smoke-run each workspace. For each of the six workspaces, run:

   yes "" | python welcome.py
   python start_here.py

   welcome.py blocks on input() calls, so stdin must be fed newlines. Capture any tracebacks.

3. Patch any further bugs found. Apply targeted edits only. Watch for other stale prefix references, missing data files, or API-rename leftovers.

4. Re-run to confirm clean. Run all six pairs again; any remaining failure loops back to step 3.

Key Files

• autolens_workspace/welcome.py — fix aa.Array2D → al.Array2D on lines 109, 112
• autogalaxy_workspace/welcome.py — audit only
• autofit_workspace/welcome.py — audit only
• HowToLens/welcome.py — audit only
• HowToGalaxy/welcome.py — audit only
• HowToFit/welcome.py — audit only
• autolens_workspace/start_here.py — audit only
• autogalaxy_workspace/start_here.py — audit only
• autofit_workspace/start_here.py — audit only
• HowToLens/start_here.py — audit only
• HowToGalaxy/start_here.py — audit only
• HowToFit/start_here.py — audit only

Original Prompt

Click to expand starting prompt

Run welcome.py and start_here.py in all workspsaces, look for the bug below and any others.

##############################
## LIGHT AND MASS PROFILES ###
##############################


    The image displayed on your screen shows a `LightProfile`, the object PyAutoLens uses to represent the
    luminous emission of galaxies. This emission is unlensed, which is why it looks like a fairly ordinary and
    boring galaxy.

    To perform ray-tracing, we need a `MassProfile`, which will be shown after you push [Enter]. The figures will
    show deflection angles of the `MassProfile`, vital quantities for performing lensing calculations.

    [Press Enter to continue]

Traceback (most recent call last):
  File "/tmp/autolens_workspace_verify_A_20260429_214047/welcome.py", line 109, in <module>
    deflections_y = aa.Array2D(values=deflections.slim[:, 0], mask=grid.mask)
                    ^^
NameError: name 'aa' is not defined. Did you mean: 'al'?

[Jammy2211]

Smoke Test Results — 2026-04-30

Workspace	Passed	Failed	Skipped	Total
autolens_workspace	7	0	0	7
autogalaxy_workspace	6	0	0	6
autofit_workspace	5	0	1	6
HowToLens	6	0	0	6

All task-relevant smoke tests passed across all four workspaces.

Note — autofit_workspace: searches/mcmc.py was SKIPPED (matches mcmc stem in no_run.yaml). overview/overview_1_the_basics.py was NOT run in smoke tests but was manually verified — it fails with TypeError: Gaussian.model_data_from() got an unexpected keyword argument 'xp', confirmed as a pre-existing failure identical on canonical main (PyAutoFit example/analysis.py API drift). This failure predates this task and is unrelated to the welcome.py fixes.

[Jammy2211]

Shipped — 2026-04-30

PRs

• fix: replace undefined aa.Array2D with al.Array2D in welcome.py #109 — aa.Array2D → al.Array2D
• fix: replace removed aplt.LightProfile plotter in welcome.py autogalaxy_workspace#49 — aplt.LightProfile(...) → aplt.plot_array(...)
• fix: make welcome.py self-contained instead of loading missing dataset autofit_workspace#45 — synthesise gaussian inline (drop missing-dataset load)
• fix: align version.txt with installed library (2026.4.13.6) HowToLens#4 — version.txt 2026.4.21.0 → 2026.4.13.6

Summary

The reported aa.Array2D NameError was the visible symptom; running welcome.py in every workspace surfaced three more bugs and one stale version pin. All six welcome.py files and all five existing start_here.py files now exit cleanly with MPLBACKEND=Agg and stdin-fed Enter presses.

Session Notes

• autofit_workspace fix approach: the original welcome.py loaded dataset/example_1d/gaussian_x1/data.json, but dataset/ is gitignored, so a fresh clone never has the file. Rather than committing the dataset or pointing at a simulator, made the welcome script self-contained — synthesise a noisy 1D Gaussian inline with numpy, matching the spirit of autolens_workspace/welcome.py and autogalaxy_workspace/welcome.py which build their demo objects in-memory.
• HowToLens version pin: the bootstrap commit (No module found #1, 2026-04-21) set version.txt to 2026.4.21.0, but no PyAutoLens release at that version exists — the installed library and every other workspace were on 2026.4.13.6. Bumping HowToLens down to 2026.4.13.6 aligns it with the rest of the ecosystem; not reverting a real release bump.
• PyAutoBuild label gap: pending-release label is registered in autolens/autogalaxy/autofit_workspace but not in HowToLens — the HowToLens PR shipped without it. Worth registering the label in HowToLens (and likely HowToGalaxy / HowToFit too) before the next workspace ship.
• Out-of-scope failure flagged for follow-up: autofit_workspace/scripts/overview/overview_1_the_basics.py smoke-fails with TypeError: Gaussian.model_data_from() got an unexpected keyword argument 'xp'. Reproduces on canonical main — pre-existing PyAutoFit API drift in example/analysis.py, unrelated to this task. Should be its own prompt.
• euclid_strong_lens_modeling_pipeline/start_here.py requires --dataset NAME — expected CLI behaviour, not a bug.