make-figures

name	make-figures
description	Use when a slide deck needs generated figures (matplotlib PDFs), when creating or editing a figure script under ml/**/py_src/, or when replacing a hand-drawn TikZ sketch or third-party image with a real generated figure.
allowed-tools	["Bash","Read","Write","Edit","Glob","Grep"]
user-invocable	true

Deck figure generation (py_src -> fig)

Every essential figure is Python-generated (matplotlib), not TikZ - that covers anything data-driven and any diagram carrying a frame's core message. TikZ is only for small throwaway visuals (quick boxes-and-arrows the frame could live without). Scripts live in a sibling py_src/, outputs go to a sibling fig/ as PDF (vector), and they run with the project venv - never a fresh environment:

./ma/Scripts/python.exe ml/CHAPTER/py_src/SCRIPT.py

Missing package? uv pip install --python ./ma/Scripts/python.exe PKG.

Required script skeleton

Copy the pattern from an existing script in the same chapter (canonical example: ml/03_classification/py_src/imbalanced_figs.py):

• Module docstring: which deck it serves, every output PDF with a one-line purpose, and the run command.
• matplotlib.use("Agg") before importing pyplot.
• SEED = 509; seed every RNG from it.
• ARM_BLUE, ARM_RED, ARM_ORANGE = "#0033A0", "#D90012", "#F2A800" - no enforced figure palette; these Armenian-flag colors are the global fallback for charts with 3+ colors (see ml/SLIDE_STYLE.md Figures section).
• Paths from Path(__file__): figures to CH_DIR / "fig", logs to REPO_ROOT / "logs" (mkdir before the FileHandler).
• logging to console + logs/<script>.log; no print. Log every saved path.
• One function per figure.

Chart rules (global, non-negotiable)

• No pie or doughnut charts, ever. Bar charts instead.
• Value labels on bars: ax.bar_label(...).
• Fonts must stay readable at slide scale - copy figsize/fontsize from an existing script in the chapter rather than inventing new values.
• Keep compute light: small sample counts, no big sweeps or long simulations without asking first (this laptop freezes under sustained load).

Verify - all four, in order

1. Script runs end-to-end under the ma venv, exit code 0, no ERROR in the log.
2. Expected PDFs exist in fig/ with non-trivial file sizes.
3. Open or render each new figure and look: labels not overlapping, nothing clipped, text legible.
4. Add the \includegraphics lines and recompile the deck (compile-deck skill) - a figure that is generated but never embedded is not done.