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ShapeCircularity
Computes the area of a shape divided by the area of a circle having the same feature.
| Name | Type | Description | |
|---|---|---|---|
 |
inShape | Path | |
|
inCircularityMeasure | CircularityMeasure | |
 |
outCircularity | Real |
Description
Circularity is a measure of similarity of a shape to the perfect circle. Circular shapes have circularity close to 1.0, while the more elongated the shape is (or contains more holes), the closer to 0.0 is its circularity.
Mathematically, the circularity is calculated as follows:
Where c denotes a
circular shape having the same feature as input shape s. The feature being considered depends on the inCircularityMeasure chosen and it is:
- the minimal bounding circle in case of BoundingCirclePreserving
- the perimeter in case of PerimeterPreserving
- the radius (maximal distance from mass center to any of the shape points) in case of RadiusPreserving
Note that if the input path is not a valid shape (i.e. it has at least one self-intersection), the computation may lead to results that are not intuitive.
Examples
Circularity with RadiusPreserving of the sample shape equals to 0.340. |
Circularity with PerimeterPreserving of the sample shape equals to 0.998. |
Errors
This filter can throw an exception to report error. Read how to deal with errors in Error Handling.
List of possible exceptions:
| Error type | Description |
|---|---|
| DomainError | Degenerate shape on input in ShapeCircularity. |
| DomainError | Not supported circularity measure in ShapeCircularity. |
| DomainError | Open path on input in ShapeCircularity. |
Complexity Level
This filter is available on Basic Complexity Level.
See Also
- RegionCircularity – Computes the area of a region divided by the area of a circular region having the same feature.
- ShapeConvexity – Computes the area of a shape divided by the area of its convex hull.
- ShapeElongation – Computes the elongation factor of a shape (perfect circle has minimal elongation equal 1.0).
