Closes #232 ## What was wrong - `src-rust/arias_intensity.rs`: the module doc and the `ARIAS_CONSTANT` doc comment gave the formula as $\frac{\pi}{2g}$, but `ARIAS_CONSTANT = G * PI / 2.0`, i.e. $\frac{\pi g}{2}$. The code is correct — it expects acceleration in units of $g$ — but the comments described the formula for acceleration in physical units, which is off by a factor of $g^2$. The `test_arias_physical_constant` comment likewise claimed the input was "1.0 cm/s^2" with an expected result of `PI / (2.0 * 981.0)`, when the input is actually 1 g and the expected result is `9.81 * PI / 2.0`. - `src-rust/cav.rs`: the module doc omitted the `G` factor the code applies, and the `test_cav_constant` comment claimed the input was "1.0 cm/s^2" with a result of "G (9.81 cm/s)", when the input is 1 g and the result is in m/s. - `src-rust/constants.rs`: `GAL` was dead code — never referenced anywhere in the Rust crate. Removed it rather than wiring up a shared definition with Python's separate `G = 981` in `IM/ims.py`, since the two live in different languages with no existing constant-sharing mechanism, and removing unused code is the smaller, lower-risk fix. - `IM/konno_ohmachi.py`: the comment above the cache pop-and-reinsert said it "shifts the key to the front of the insertion order," but `dict.pop` + re-assignment actually moves the key to the *end* (most recently inserted position). The eviction loop a few lines down does walk from the front (oldest first), so the cache logic itself is correct — only the comment had the direction backwards. No numerical or behavioral change; comments and one unused constant only. ## How the new test shows it `test_arias_physical_constant` previously asserted the result against `ARIAS_CONSTANT` itself, which is circular: it would pass regardless of whether the constant matched the documented formula. Changed the assertion to compare against the literal `9.81 * PI / 2.0` from the corrected comment. If `ARIAS_CONSTANT` were changed to match the old, wrong comment's formula (`PI / (2.0 * 981.0)` ≈ 0.0016 vs. the correct ≈ 15.41), this test would now fail, whereas it previously would not have caught that. ## What to check closely - The corrected formulas/comments in `arias_intensity.rs` and `cav.rs` match the actual runtime behavior of `arias_intensity`/`cav` (inputs in units of $g$). - Confirm `GAL` truly has no other consumers (checked via grep across the Rust sources; only `constants.rs` defined it). _Cost $0.43, 27 turns._ 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

Commits

Commits on Sep 30, 2026

Fix misleading unit comments in CAV/Arias/LRU code; drop unused GAL