Description
Return whole observationYear-sourceYear age and whether the source year is later than observation year.
Historical and regional records connect source vintages, era coordinates, folio sides, time coverage and locally defined units. Literal tokens and supplied offsets can organize metadata without authenticating an archive or establishing historical calendar equivalence. Preserve the original source and its conventions.
Return whole observationYear-sourceYear age and whether the source year is later than observation year.
When to use this tool
Use Toponym Source Vintage Age when checking the stated regional archival, chronology, coverage or unit convention.
How to use the tool and how it works
- Enter observationYear, sourceYear. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read ageYears, futureSource. Inspect futureSource before interpreting the associated values.
Return whole observationYear-sourceYear age and whether the source year is later than observation year.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| observationYear | Observation Year | Required. Safe integer. |
| sourceYear | Source Year | Required. Safe integer. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| ageYears | Age Years | Required. Safe integer. |
| futureSource | Future Source | Required. Boolean. |
{
"input": {
"observationYear": 2026,
"sourceYear": 1980
},
"output": {
"ageYears": 46,
"futureSource": false
}
}Limitations and assumptions
- Negative age is retained; record vintage does not establish a place name's historical validity or source authority.
- 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
Consult the original archive and appropriate historical/calendar/unit authorities for provenance and substantive interpretation.
References
Similar or alternative tools
- Archive Reference Folio Side
Check literal endings, reject if both match, strip the recognized suffix and return recto, verso or unspecified with a recognized flag.
- African Map Coordinate Reference Caption
Preserve an explicit map coordinate-reference caption and source without assigning a coordinate system.