Dew Point 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

t4-289

Effect

Computation or source lookup only

Input and validation requirements

RH=0 produces an undefined logarithm and must be rejected. The specification does not state validation behavior for this input. It also does not define comfort-category thresholds or explicitly state the temperature-unit convention, creating additional implementation hazards.

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": {
    "temperature_C": 20,
    "relative_humidity_percent": 50
  },
  "expected_outputs": {
    "dew_point_C": 9.254,
    "dew_point_F": 48.657
  },
  "working": "alpha=ln(50/100)+(17.27*20)/(237.7+20)=ln(0.5)+345.4/257.7=-0.693147+1.340318=0.647171. Td=(237.7*0.647171)/(17.27-0.647171)=153.8325/16.622829=9.254 °C. Fahrenheit=9.254*9/5+32=16.657+32=48.657 °F."
}

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