Error hunt ~6 min · ~26 min remaining

Diagnose sweeps

Identify residual state, partial CSV output, and confusion between validation_pass and feasible.

Bug hunt

Open 09_bug_hunt.mac. It contains five common parametric-sweep defects:

Error	Symptom	Check	Cause	Minimum fix
1	Impossible topology	Node counts	No rebuild between cases	`VCLEAR` + `VDELE` in build
2	Single-row CSV	Output file	CSV written in extract	Write only from the driver
3	h=0.08 selected	`feasible`	Confused with `validation_pass`	Filter by design limits
4	Inconsistent loop	`/STATUS,PARM`	`/CLEAR` inside `*DO`	Clear geometry, not the session
5	h=0.14 selected	`selected_h`	Largest acceptable height chosen	`min(beam_h)` with `feasible=1`

Professional incident

The sweep selects a design containing an invalid case.

Incident file

This is not your session template — it is a broken script for diagnosis practice.

Evidence to retain

Initial hypothesis Changed line or block Output proving the cause Reusable prevention rule

What evidence separates the root cause from a lucky edit?

Your reflection stays in this browser.

Graduated hints

1 · Concept hint

Find the first broken contract.

2 · Command hint

Inspect state related to *DO, *IF, and /CLEAR.

3 · Explained solution

Compare with the module deliverable and explain why the corrected state restores the contract.

After running the script, reviewing the .out, and saving evidence, answer:

Quick check

The CSV contains only the last row of the sweep. What is the most likely cause?

Each submacro writes m09_results.csv, so the last iteration overwrites it. The deflection tolerance is too strict. SOLID185 is missing KEYOPT(2)=3.