Graduated Circle Overlap Risk Radius Checker
Graduated circle positive-area overlap screen from center separation; tangency reported separately.
Description
Screen two circular map symbols for positive-area overlap and external tangency.
Graduated map symbols are often represented as disks. Comparing their radii with center separation provides a quick geometric overlap screen before reviewing the actual symbol layout.
When to use this tool
Screen two circular map symbols for positive-area overlap and external tangency. Use it when the input measurements and conventions below match the operation you need.
- Prepare radiusAMm, radiusBMm, centerDistanceMm, respecting the measurement basis and boundaries below.
- Compare the worked example with your intended operation before reusing its result.
How to use the tool and how it works
- Enter every field in the input table using the stated units and exact supported selector spelling where applicable.
- Run the tool. Correct input errors before interpreting an output.
- Read the result fields below; use accompanying flags and the stated sign, boundary or model convention when interpreting a number.
All three distances must be nonnegative. positiveAreaOverlap requires both radii to exceed zero and centerDistanceMm to be less than their sum. tangent is a separate exact comparison of center distance with the sum of radii.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| radiusAMm | Radius a mm. Millimeters. | Finite number |
| radiusBMm | Radius b mm. Millimeters. | Finite number |
| centerDistanceMm | Center distance mm. Millimeters. | Finite number |
| Output field | Interpretation |
|---|---|
| result | Object containing the following named result fields. |
| result.positiveAreaOverlap | True when both radii are positive and center separation is smaller than their sum. |
| result.tangent | Exact equality of center distance and the sum of radii, including degenerate radius cases. |
{
"input": {
"radiusAMm": 2,
"radiusBMm": 3,
"centerDistanceMm": 4
},
"output": {
"result": {
"positiveAreaOverlap": true,
"tangent": false
}
}
}Limitations and assumptions
- The tool does not calculate intersection area or visual obstruction. Internal tangency is not separately classified; the tangent flag uses the external-distance equality and can also be true for degenerate zero-radius inputs.
- Every declared field is required and unexpected fields are rejected. Numeric inputs must be finite; input errors are distinct from a valid false result or an explicitly qualified output.
- Extremely large inputs and nonfinite or excessively large outputs are rejected. List positions reported by the tool use zero-based indices unless stated otherwise.
Alternative or Complementary methods
For a map-layout decision, inspect the rendered map at its intended size as well as its numerical dimensions. For classification or coordinate work, retain the chosen boundary and coordinate conventions with the result. Compare the scope of the nearby tools below before substituting one.
References
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