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Module: FoundationBasic

Approximates points with a circle using selected outliers suppression method.

Name Type Description
Input value inPoints Point2DArray
Input value inRange Range* Determines which array points take part in fitting process
Input value inFittingMethod CircleFittingMethod
Input value inOutlierSuppression MEstimator*
Output value outCircle Circle2D? Fitted circle or nothing if method failed to converge
Output value outInliers Point2DArray Points matching the computed circle


The operation computes a circle which approximates the input points best. Several methods are available, AlgebraicKasa being the fastest one. It is also the most inaccurate when the input points are sampled along small arc only.


Description of usage of this filter can be found in examples and tutorial: Calibration World Coordinates On Original Images.

The resulting outCircle drawn with the input points, inFittingMethod = AlgebraicKasa and inOutlierSuppression = Auto.


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 Outlier suppression is supported only in algebraic fitting methods.
DomainError Range exceeds the input point array in FitCircleToPoints.

Complexity Level

This filter is available on Advanced Complexity Level.

See Also

  • FitArcToPoints – Approximates points with an arc using the selected outliers suppression method.
  • FitLineToPoints – Approximates points with a line using the Least Squares method.