Description
Encode an east/west compass-deviation magnitude under a supplied sign convention.
Nautical quantities require explicit north, datum, sign, station and unit conventions. A wrapped bearing error has a chosen opposite-direction endpoint, while a circular sector has its own start and end policy. Supplied polar speeds, tank factors and tide labels are references rather than verified navigation or vessel conditions.
Encode an east/west compass-deviation magnitude under a supplied sign convention.
When to use this tool
Use Compass Deviation East West Token when you already have magnitudeDegrees, eastPositive, eastward and need to encode an east/west compass-deviation magnitude under a supplied sign convention.
How to use the tool and how it works
- Enter magnitudeDegrees, eastPositive, eastward. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read signedDegrees, label. Use the output convention below.
Require magnitudeDegrees>=0; signedDegrees is positive when eastward equals eastPositive and negative otherwise; label magnitude with E or W.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| magnitudeDegrees | Magnitude Degrees | Required. Finite number; minimum 0. |
| eastPositive | Selects the caller's sign convention; no magnetic model is consulted. | Required. Boolean. |
| eastward | Eastward | Required. Boolean. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| signedDegrees | Signed Degrees | Required. Finite number. |
| label | Label | Required. Text; maximum UTF-16 length 8192. |
{
"input": {
"magnitudeDegrees": 3,
"eastPositive": true,
"eastward": true
},
"output": {
"signedDegrees": 3,
"label": "3 E"
}
}Limitations and assumptions
- The deviation and convention are supplied; no compass, magnetic variation, correction table or actual heading is inferred.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use verified charts, observations, vessel documentation and the complete relevant geometric or hydrostatic model for a navigational question. Preserve the local bearing/datum convention and treat scalar factors or sector checks as limited inputs rather than operational decisions.
References
Similar or alternative tools
- Transit Bearing Signed Error
Calculate a wrapped signed transit-bearing error.
- Tide Observation Low High Phase Token
Label a tide observation's recorded low/high or changing phase.