Date Time End Of Day Carry Field Tool

Description

Normalize a date-time end-of-day hour field.

Timestamp notation distinguishes written precision, quantization and carry into the next larger field. Padding a fraction, rounding it and propagating an end-of-day marker are different operations and do not establish clock accuracy.

Normalize a date-time end-of-day hour field.

When to use this tool

Use Date Time End Of Day Carry Field when checking one explicit timestamp precision, rounding or carry convention.

How to use the tool and how it works

Enter hour, minute, second. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read hour, dayCarry. Use the output convention below.

Normalize a date-time end-of-day hour field. Require hour 0-24/minute and second 0-59, allowing hour 24 only with both zero; return normalized hour and dayCarry.^[1]

Input field	Meaning and units	Accepted input
hour	Hour	Required. Safe integer; minimum 0; maximum 24.
minute	Minute	Required. Safe integer; minimum 0; maximum 59.
second	Second	Required. Safe integer; minimum 0; maximum 59.

Output field	Interpretation	Returned shape
hour	Hour	Required. Safe integer.
dayCarry	Day Carry	Required. Safe integer.

json

{
  "input": {
    "hour": 24,
    "minute": 0,
    "second": 0
  },
  "output": {
    "hour": 0,
    "dayCarry": 1
  }
}

Limitations and assumptions

Only the hour and carry are returned; apply the carry separately to an actual calendar date.
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 complete date-time arithmetic when a carry must change a date or interact with timezone transitions.

References

Calculation and input contract: date/date-time-end-of-day-carry-field — tool.io

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