Description
Add 209 days to verifiedRisshunDate and return inclusiveOrdinal 210.
Some traditional Japanese seasonal dates are counted inclusively from Risshun. The astronomical origin date must be known before a fixed ordinal can be converted to a Gregorian date.
Add 209 days to verifiedRisshunDate and return inclusiveOrdinal 210.
When to use this tool
Use Japanese Nihyakutoka Date Calculator when you need a fixed traditional ordinal from a verified Risshun date.
How to use the tool and how it works
- Enter verifiedRisshunDate. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read result. Expand result to inspect the returned fields.
Add 209 days to verifiedRisshunDate and return inclusiveOrdinal 210. The supplied origin counts as day one.1
Nihyakutoka is the 210th day counted from Risshun. Inclusive counting makes its Gregorian offset 209 days from the supplied origin.2
| Input field | Meaning and units | Accepted input |
|---|---|---|
| verifiedRisshunDate | Previously verified Gregorian Risshun date, YYYY-MM-DD, in years 0001-9999; output must stay within that year range. | Required. Text. Implementation limit: 8192 Unicode code points and 16384 UTF-16 code units. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| result | Result | Required. Object. |
| result.date | Date | Calculated result member: string. |
| result.inclusiveOrdinal | Inclusive Ordinal | Calculated result member: number. |
{
"input": {
"verifiedRisshunDate": "2024-02-04"
},
"output": {
"result": {
"date": "2024-08-31",
"inclusiveOrdinal": 210
}
}
}Limitations and assumptions
- The Gregorian origin date must already be verified; the tool does not calculate the solar term, a weather forecast, or agricultural conditions.
- Outputs are nested inside result. 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.
Alternative or Complementary methods
Obtain the relevant year's origin from an authoritative almanac rather than assuming a fixed Gregorian date.
References
-
Calculation and input contract: japanese-calendar/nihyakutoka — tool.io
-
Glossary on Solar Terms: Zassetsu — National Astronomical Observatory of Japan
Similar or alternative tools
- Japanese Hachijuhachiya Date Calculator
Add 87 days to verifiedRisshunDate and return inclusiveOrdinal 88.
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