Description
Compute each next-minus-current step and measuredStep-referenceStep.
Landform change is often summarized by differences in height, area, volume, or storage over a defined interval. A signed budget preserves gains and losses, but its meaning depends on a common spatial support and reference surface.
Compute each next-minus-current step and measuredStep-referenceStep.
When to use this tool
Use Profile Reference Step Gap when you need a local geomorphic change or storage-budget calculation.
How to use the tool and how it works
- Enter profileHeights, referenceHeights, selectedStep. Keep parallel arrays aligned. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read measuredStep, referenceStep, stepGap. Use the output convention below.
Require aligned profile and reference heights and selectedStep with an available next entry. Compute each next-minus-current step and measuredStep-referenceStep.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| profileHeights | Profile Heights | Required. Array of finite number; maximum items 256. |
| referenceHeights | Reference Heights | Required. Array of finite number; maximum items 256. |
| selectedStep | Selected Step | Required. Safe integer; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| measuredStep | Measured Step | Required. Finite number. |
| referenceStep | Reference Step | Required. Finite number. |
| stepGap | Step Gap | Required. Finite number. |
{
"input": {
"profileHeights": [
1,
4,
5
],
"referenceHeights": [
1,
3,
5
],
"selectedStep": 0
},
"output": {
"measuredStep": 3,
"referenceStep": 2,
"stepGap": 1
}
}Limitations and assumptions
- Profiles must already be spatially aligned and use a common vertical reference; this compares discrete differences without dividing by spacing, fitting curvature, or identifying a process.
- 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
Compare aligned surveys and their uncertainty over the same spatial support. A full mass or volume balance should include omitted fluxes, evolving geometry, and measurement error.
References
Similar or alternative tools
- Bank Retreat Reference Axis Sign
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- Erosion Pin Reference Exposure Delta
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