open-standards/wai/quantum-conformance/qudit/README.md

# Qudit jobs: the conformance set

Registers of qudits of 2, 3, 4 or 6 levels and the job that runs them,
`wai.quantum.qudit/1` ([quantum-sim.md §9](../../extensions/quantum-sim.md)).
A conforming host reads each request, runs it and gives each answer here bit for
bit, and refuses each refusal with its code.

`vectors.json` holds:

| member | what |
|---|---|
| `limits` | the most amplitudes a register holds, gates a program holds, shots, amplitudes asked for and work a job takes (§9.7, §9.8) |
| `constants` | for each dimension, its roots of unity `ω_d^k` and its Fourier entries `ω_d^m/√d` as the integers they are at `2^30`, and their digest (§9.2) |
| `vectors` | 29 requests, each with the answer a conforming host gives: every member of a run's answer but `engine`, `schema`, `energy` and `receipt`, which a host adds (§9.7). Every gate and every power on every dimension; Bell pairs and both sides of the Weyl relation; `F`, `F²` and `F†`; programs with the bound 0; a column of every Fourier gate, each entry times an amplitude of exactly 1; the least and the largest seed; registers from one qudit to 14 qubits |
| `refusals` | 35 requests a conforming host refuses, each with its code: `J090` (does not read), `J091` (a dimension with no roots held), `J092` (past a limit), in the order §9.7 checks them |
| `results_blake3` | BLAKE3 over each vector's request and result as compact JSON (doubles as serde_json writes them), each followed by a newline |

## Who checks it

- **The engine**, on every host CI runs (`wai/wai-quantum/tests/qudit_conformance.rs`, in
  `.github/workflows/wai-quantum-qudit.yml`): arm64 macOS, x86_64 Linux, and
  wasm32-wasip2 under wasmtime, each required to write this file byte for byte.

  ```sh norun=ci:wai-quantum-qudit.yml
  cargo test --locked --release --no-default-features --features quantum_engine,quantum_receipt --test qudit_conformance
  ```

- **A second implementation**, in Python, from §9's text alone
  (`../tools/qudit_referee.py`): the constants by the text's rule in whole numbers,
  each gate index by index, the sampler shot by shot, the bounds in doubles, the
  refusals in the text's order, and the results' digest; then it moves each
  irrational constant by one unit and requires some vector's state to move.

  ```sh norun=ci:wai-quantum-qudit.yml
  python3 -I wai/quantum-conformance/tools/qudit_referee.py wai/quantum-conformance
  ```

`WAI_QUANTUM_BLESS=1` with the engine's test writes the file again from the cases
in the test. A change to it changes `results_blake3`, which the test pins.

## What it does not cover

- The receipt: a qudit job is sealed as every job is, and `../receipts/` holds
  those receipts' corpus.
- The largest registers: the vectors stop at 16384 amplitudes; the limits and
  their refusals are here, and the measured ceiling is in §9.8.
- Noise, measurement in the middle, and any dimension but 2, 3, 4 and 6, which
  §9 does not state.