# 📐 L2 Spec — Spectral Estimation Uniform-Sampling Spec (subspace methods)
**ID:** `L2-394-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-394`](/artifact/l1/L1-394)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.3 · **Delta tier:** 5
> **⛓ On-chain block:** 41555202
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| K | — | 1 – 64 |
| N | — | 32 – 16384 |
| Snr db | dB | -10 – 40 |
| Delta omega | — | 0.001 – 0.5 |
| Windowing error | — | 0.0 – 0.5 |
| K overestimation | — | 0 – 30 |
| Sampling irregularity | — | 0.0 – 0.5 |
## 2. Tolerance (ε)
**Type:** `fn`
```
5e-4 + 1.0 / (N * 10**(SNR_dB/20)) + 0.02 * max(0, 4*3.14159/N - delta_omega)
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.3 |
| Delta tier | 5 |
## 4. Fingerprint
`108ba80b4d76c7e7129caf857e07a4549899080ec58f1f854f500cd31f769050`
## 5. On-chain Registration
- **Chain hash:** `0xa5dbdf44ada0e68b5b428eb9fd44d5cbe996fa414982c6c650f65c525d9c9bb9`
- **Chain tx hash:** `0x43c46a70e503f8667c918cb229b4eb8626c14fe316a0df27c6e36519d43c3466`
- **Chain block:** `41555202`
---
## File Mapping
This bundle consists of: `L2-394-001.md`, `L2-394-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-394-001.md` | Source of truth — edit this | Human or LLM |
| `L2-394-001.json` | Structured metadata for the registry | LLM regenerates from the sections above |
**Prompt for your LLM after editing this Markdown:**
> Read the attached Markdown. Regenerate the sibling `.json` so every field matches.
> Preserve the schema documented in the rows above.
> Output each file in its own fenced code block tagged with the filename.
> Output only the JSON object.
_This Markdown was auto-synthesized from the catalog row for `L2-394-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._