Description
Retain UTC versus local-coordinate order witnesses from paired event offsets; no reordering or claim that fold observations are corrupt.
An offset maps a supplied UTC coordinate to local civil coordinates by local = UTC + offset. Half-open spans include their start and exclude their end. A forward offset jump can leave local coordinates uncovered; a backward jump can give several UTC interpretations of one local value. These tools use explicit synthetic civil-second observations rather than a named-zone database.
Retain UTC versus local-coordinate order witnesses from paired event offsets; no reordering or claim that fold observations are corrupt.
When to use this tool
Use this tool to retain UTC versus local-coordinate order witnesses from paired event offsets; no reordering or claim that fold observations are corrupt.
How to use the tool and how it works
- Enter utc, offsets using the definitions below.
- Run the operation. Resolve input-format errors before interpreting an output.
- Read result.local, result.utcDescending, result.localDescending, using the stated boundary, ordering, sign and absence conventions.
Require aligned UTC and offset lists. Compute local[j]=utc[j]+offsets[j], then separately report later indexes where UTC or local values strictly decrease.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| utc | Explicit UTC observation coordinates in seconds within ±10¹². | Dense list of at most 128 finite numbers, under the stated integer/range rules. |
| offsets | Signed offset seconds within ±86,400, aligned one-to-one with utc. | Dense list of at most 128 finite numbers, under the stated integer/range rules. |
| Output field | Interpretation |
|---|---|
| result | Object containing the fields below. |
| result.local | Input-order UTC+offset local second coordinates. |
| result.utcDescending | Later source indexes with strictly decreasing UTC observations. |
| result.localDescending | Later source indexes with strictly decreasing local observations. |
{
"input": {
"utc": [
19,
20
],
"offsets": [
2,
0
]
},
"output": {
"result": {
"local": [
21,
20
],
"utcDescending": [],
"localDescending": [
1
]
}
}
}Limitations and assumptions
- Equal values are not descending. Local order can reverse across a backward offset change even when UTC order increases.
- Span/transition coordinates are finite seconds within ±10¹² and offsets within ±86,400 seconds. Spans require start<end. No IANA database, calendar parsing, daylight-saving inference or leap seconds are included.
- Every declared outer field is required and unknown outer fields are rejected. Strings and JSON text have size limits, lists are bounded to 128 entries, and JSON nesting/node counts are bounded. Tighter operation-specific bounds stated above take precedence.
- Ordinary numeric outputs must be finite and within safe-integer magnitude. Exact large lengths/counts use decimal strings. Original record indexes and code-unit positions are zero-based; span ends are exclusive unless stated otherwise.
Alternative or Complementary methods
Keep all timestamps on one origin and in seconds, and retain gaps or competing observations. Use a maintained time-zone library when real dates, named zones or historical rules are required.
References
Similar or alternative tools
- Time Zone Local Ambiguity Classifier
Classify supplied local candidates without claiming missing evidence proves a real civil-clock gap; repeated/overlapping observations remain ambiguous.
- Time Zone Local Candidate Policy Selector
Choose earliest/latest UTC candidate or unique-only under an explicit policy; empty or unresolved evidence returns null.