# Kernel worked example

Package version: 1.0.0 · prepared 2026-09-05.

## What this checks

Checks the fidelity, reference-projection gap, and their normalized weighted sum for two real two-dimensional states at 60 and 90 degrees.

Paper DOI: https://doi.org/10.1186/s13040-026-00519-3

The external paper-associated archive is https://doi.org/10.5281/zenodo.17652604. That archive is distinct from this small portfolio-authored package. Its installation environment and full experiments were not executed here.

## Run locally

Prerequisite: Python 3.10 or later, CPU only. No third-party packages, GPU, network, credentials, or dataset download is required.

Extract the complete ZIP, open a terminal in its folder, and run:

```sh
python check.py
```

An assertion failure exits nonzero. A successful check prints the numeric result and a scope-specific PASS message. The equivalent notebook contains the same Python code; open notebook.ipynb with its working directory set to this extracted folder. A notebook environment is optional and is not bundled.

## Expected output

Fidelity 0.933012701892; reference gap 0.025255128608; combined kernel 0.479133915250.

Numeric reference values are in expected.json. The scripts check them deterministically; there is no random seed or stochastic training.

## Inputs and provenance

source.json contains explicitly chosen teaching angles and weights, not patient data.

provenance.json records the source, scope, package version, and SHA-256 hashes of the executable check, input data, and expected output. README, Python, equivalent notebook, source JSON, expected JSON, and provenance are included together in the ZIP.

## Limits

This is an authored worked example of the kernel definition, not ECG feature extraction, patient-level splitting, model fitting, or a rerun of reported accuracy. The UI uses alpha + beta = 1; the paper tunes the weights separately.

Fresh network verification of the external archive was unavailable during package preparation. These small checks use the portfolio's existing sourced transcription, not a newly downloaded archive. A successful check must not be described as reproducing the full paper.