Description
Subtract overlap from firstArea + secondArea for unionArea.
An area share depends on the chosen footprint and whether overlapping or excluded regions enter the denominator. Geometric coverage does not automatically imply functional capacity.
Subtract overlap from firstArea + secondArea for unionArea.
When to use this tool
Use Irrigation Zone Overlap Area Correction when you need a declared area fraction or overlap correction.
How to use the tool and how it works
- Enter firstArea, secondArea, overlap. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read unionArea, doubleCountFraction. Use the output convention below.
Subtract overlap from firstArea + secondArea for unionArea. Divide overlap by the uncorrected sum for doubleCountFraction.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| firstArea | First Area | Required. Finite number; minimum 0. |
| secondArea | Second Area | Required. Finite number; minimum 0. |
| overlap | Overlap | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| unionArea | Union Area | Required. Finite number. |
| doubleCountFraction | Double Count Fraction | Required. Finite number. |
{
"input": {
"firstArea": 60,
"secondArea": 50,
"overlap": 10
},
"output": {
"unionArea": 100,
"doubleCountFraction": 0.09090909090909091
}
}Limitations and assumptions
- The denominator is the summed areas rather than the union; overlap is supplied and irrigation efficiency is not measured.
- 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 boundaries and the relevant drainage, planting, or architectural model before interpreting the share.
References
Similar or alternative tools
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- Planter Edge Area Remainder
Subtract plantedArea from outerArea for edgeArea and divide by positive outerArea.