Description
Multiply stage-referenceStage by +1 when positiveUp and -1 otherwise.
A level reading is measured relative to an origin or datum. Adding an offset can express the same supplied observation in another compatible coordinate, while changing the reference label alone does not transform a datum.
Multiply stage-referenceStage by +1 when positiveUp and -1 otherwise.
When to use this tool
Use Stream Stage Reference Sign when you need one signed level, datum, or reference comparison.
How to use the tool and how it works
- Enter stage, referenceStage, positiveUp, equalityCountsAbove. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read signedGap, aboveUnderRule. Inspect aboveUnderRule before interpreting the associated values.
Multiply stage-referenceStage by +1 when positiveUp and -1 otherwise. Compare signedGap with zero using equalityCountsAbove for inclusive handling.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| stage | Stage | Required. Finite number. |
| referenceStage | Reference Stage | Required. Finite number. |
| positiveUp | Positive Up | Required. Boolean. |
| equalityCountsAbove | Equality Counts Above | Required. Boolean. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| signedGap | Signed Gap | Required. Finite number. |
| aboveUnderRule | Above Under Rule | Required. Boolean. |
{
"input": {
"stage": 5,
"referenceStage": 3,
"positiveUp": true,
"equalityCountsAbove": false
},
"output": {
"signedGap": 2,
"aboveUnderRule": true
}
}Limitations and assumptions
- Readings share a datum and unit; aboveUnderRule follows the supplied orientation rather than independently establishing geographic elevation or flood status.
- 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
Verify the survey references, measurement direction, and calibration before using levels in an operational decision.
References
Similar or alternative tools
- River Stage Rising Falling Flag
Subtract previousStage from currentStage, divide by positive elapsedHours, and label steady when absolute change is within nonnegative tolerance; otherwise label rising or falling.
- Staff Gauge Overlap Reading Gap
Compare firstReading+firstZero with secondReading+secondZero.