Description
Return elevation-fittedPlaneElevation and squared residual times cellArea/totalArea.
Geomorphic geometry uses lengths, areas, volumes, and dimensionless shape ratios to summarize a feature. Grain axes, channel dimensions, and angular units need explicit definitions because similar field names can describe different measurements.
Return elevation-fittedPlaneElevation and squared residual times cellArea/totalArea.
When to use this tool
Use Landsurface Roughness One Cell Residual when you need a geometric summary of a supplied landform or sediment measurement.
How to use the tool and how it works
- Enter elevation, fittedPlaneElevation, cellArea, totalArea. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read residual, squaredAreaWeightedContribution. Use the output convention below.
Require positive totalArea and cellArea within it. Return elevation-fittedPlaneElevation and squared residual times cellArea/totalArea.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| elevation | Elevation | Required. Finite number. |
| fittedPlaneElevation | Fitted Plane Elevation | Required. Finite number. |
| cellArea | Cell Area | Required. Finite number; minimum 0. |
| totalArea | Total Area | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| residual | Residual | Required. Finite number. |
| squaredAreaWeightedContribution | One squared residual times cellArea/totalArea; not a complete RMS roughness. | Required. Finite number. |
{
"input": {
"elevation": 105,
"fittedPlaneElevation": 102,
"cellArea": 4,
"totalArea": 100
},
"output": {
"residual": 3,
"squaredAreaWeightedContribution": 0.36
}
}Limitations and assumptions
- Elevations share units and datum; the contribution has squared-height units and is not a complete RMS roughness, fitted plane, or terrain-quality assessment.
- 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
Inspect the measured feature and sampling method for the intended geometric definition. Use a spatial model or complete distribution when a single shape ratio or local term is insufficient.
References
Similar or alternative tools
- Profile Curvature Sign Term
Take the sign of supplied secondDerivative and reverse it when elevationPositiveUp is false.
- Profile Reference Step Gap
Compute each next-minus-current step and measuredStep-referenceStep.