Source: https://guthlabs.ai/docs/instruments/deep-water-wave-speed-period/implementation/

instrument implementation / implementation-contract

# Deep-Water Wave Speed & Period implementation

A source-bound implementation contract for Deep-Water Wave Speed & Period; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t5-127

**Effect**: Computation or source lookup only

## Input and validation requirements

The literal plain-arithmetic implementation overflows at a period of 1e308 s even though the phase-speed expression can be algebraically rearranged to produce a finite value; it also lacks a supplied non-deep-water branch and does not define handling for negative periods.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "period_s": 6,
    "g_m_s2": 9.80665
  },
  "expected_outputs": {
    "phase_speed_m_s": 9.364660936,
    "wavelength_m": 56.187965616,
    "group_velocity_m_s": 4.682330468
  },
  "working": "c = gT/(2π) = (9.80665 × 6)/(2 × 3.141592653589793) = 58.8399/6.283185307179586 = 9.364660936 m/s. L = cT = 9.364660936 × 6 = 56.187965616 m. c_g = c/2 = 9.364660936/2 = 4.682330468 m/s."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/deep-water-wave-speed-period/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/deep-water-wave-speed-period/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/deep-water-wave-speed-period/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche5/tranche5-results.json`