Declaration: TCurveFit.CalcCircleFit (var r, dx, dy: double);
The procedure CalcCircleFit calculates the best fitting circle for a given set of data. The circle is determined by the equation

The values of x and y are given by the data samples, the parameters dx, dy, and r are estimated by CalcCircleFit using a least squares approximation.

The data points [x,y] have to be entered using the routine EnterStatValue. A minimum number of 3 values is required in order to apply CalcCircleFit. Do not forget to reset the statistics calculation before entering any new data sets (use Init)