Description
Calculate signed rise/run gradient and its percentage-grade representation.
Geomorphic measurements distinguish signed coordinates, grain-size scales, profile derivatives and transported-mass or cross-section bases. A supplied datum adjustment or threshold does not detect a landform or establish a process. Plan distance, profile second derivative and slope-normalized curvature are different quantities.
Calculate signed rise/run gradient and its percentage-grade representation.
When to use this tool
Use Terrain Rise Run Gradient when checking the stated local landform, sediment, profile or coordinate convention.
How to use the tool and how it works
- Enter rise, horizontalRun. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read gradient, percentGrade. Use the output convention below.
Require horizontalRun>0. Return signed rise/run and 100 times that ratio as percentGrade.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| rise | Rise | Required. Finite number. |
| horizontalRun | Horizontal Run | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| gradient | Rise/run dimensionless ratio. | Required. Finite number. |
| percentGrade | 100*rise/run; not degrees or radians. | Required. Finite number. |
{
"input": {
"rise": 12,
"horizontalRun": 300
},
"output": {
"gradient": 0.04,
"percentGrade": 4
}
}Limitations and assumptions
- Rise and run need compatible length units; percent grade differs from an angle in degrees and does not establish slope safety.
- 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 calibrated surveys, mapped geometry and suitable complete sediment/terrain models for trends, process interpretation, uncertainty or hazard assessment.
References
Similar or alternative tools
- River Knickpoint Gradient Residual
Compare a supplied river gradient with its reference gradient.
- Hillslope Profile Curvature Three Point Term
Calculate a three-point elevation-profile second derivative at equal horizontal spacing.