Cents / Pitch Deviation Calculator implementation

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

t4-121

Effect

Computation or source lookup only

Input and validation requirements

The formula produces undefined results for zero frequencies, but the specification does not state positive-frequency validation or rejection behavior. It also leaves the sign/order convention to the interface beyond the formula notation, creating a plausible +1200 versus -1200 interpretation.

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": {
    "f1": 440,
    "f2": 440,
    "unit": "Hz"
  },
  "expected_outputs": {
    "cents": 0
  },
  "working": "f1/f2 = 440/440 = 1. log2(1) = 0. cents = 1200 × 0 = 0 cents."
}

Other records

Sources and evidence

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

• VERIFIED_LEDGER.json
• evidence-tranche4/tranche4-results.json