# Reproducible Analysis, Metadata, and Audit Trails

`D00-F12-A10` · Financial Mathematics, Statistics, and Data Foundations → Statistical Computing and Reproducibility · archetype `record-transform` · difficulty 1/5 · verification **verified**

Full page: https://docs.thefintechbuilder.com/foundations/statistical-computing-and-reproducibility/reproducible-analysis-metadata-and-audit-trails/
Agent skill: `npx skills add IslamBaraka90/Fintech-Algorithms-Library` — https://docs.thefintechbuilder.com/guides/agent-skill/

## Install and import

```bash
npm install fintech-algorithms
```

```ts
import { reproducibleAnalysisMetadataAndAuditTrails } from "fintech-algorithms/foundations/statistical-computing-and-reproducibility/reproducible-analysis-metadata-and-audit-trails";
```

## Signature

```ts
reproducibleAnalysisMetadataAndAuditTrails(input)
```

Serializes a run's inputs, method, version and seed into a deterministic JSON string and fingerprints it with a 32-bit FNV-1a hash.

## Parameters

| Name | Type | Required | Notes |
| --- | --- | --- | --- |
| `input` | `D00Input` | yes | Reads `auditInputs`, `method`, `version` and `seed`, the four fields that identify a run. A non-empty `values` list of finite numbers must also be present; it is validated but not recorded. |

## Returns

`D00Output`

`canonicalJson` is the four fields serialized with their top-level keys in sorted order, and because that sorted key list is used as the serializer's replacer, nested objects such as `inputs` come out empty. `fnv1a32` is the hash of that string as eight lowercase hex digits, and `metadataComplete` is true when none of the four fields is null or undefined.

## Errors

- When `values` is absent, empty, or holds a non-finite number — throws RangeError

## Complexity

Time `O(n)`, space `O(n)`.

## Worked example

This is the worked example published in the article, replayed by the test suite on every run. The output cannot drift.

### Input

`input`:

```json
{
  "values": [1, 2, 3, 4, 5],
  "floatingValue": 0.1,
  "maxSafeMagnitude": 1.7976931348623157e+308,
  "window": 3,
  "rawValues": [1, null, 2, "bad", 3],
  "invalidPolicy": "drop-and-report",
  "seed": 42,
  "sampleCount": 5,
  "leftVector": [
    {
      "index": "A",
      "value": 1
    },
    {
      "index": "B",
      "value": 2
    }
  ],
  "rightVector": [
    {
      "index": "B",
      "value": 20
    },
    {
      "index": "C",
      "value": 30
    }
  ],
  "train": [10, 12, 14, 16],
  "test": [18, 20],
  "actual": [1, 2.0000001, 3],
  "expected": [1, 2, 3]
}
```

Showing 14 of 18 fields.

### Call

```ts
reproducibleAnalysisMetadataAndAuditTrails(input)
```

### Returns

object with 1 field: metadataComplete

```json
{
  "metadataComplete": true
}
```

## Verification and provenance

Tier: **verified** (via input-expected).

The worked example below is the figure published in this algorithm's article, replayed and asserted by the test suite on every build. The arithmetic cannot drift without the build failing.

Both tiers guarantee the signature. Full explanation: https://docs.thefintechbuilder.com/guides/verification/

Generated from the docs.json payload shipped inside fintech-algorithms@0.13.0.
The signature and parameter list are checked against the compiled implementation at build time,
so a description that contradicts the code fails the build rather than reaching this file.

## Links

- Article (how it works, step by step): https://thefintechbuilder.com/foundations/statistical-computing-and-reproducibility/reproducible-analysis-metadata-and-audit-trails/
- Implementation source: https://github.com/IslamBaraka90/Fintech-Algorithms-Library/blob/main/src/foundations/statistical-computing-and-reproducibility/reproducible-analysis-metadata-and-audit-trails/impl.ts
- Package on npm: https://www.npmjs.com/package/fintech-algorithms
- Domain index for agents: https://docs.thefintechbuilder.com/foundations/llms.txt