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Home Programming DataLab DLabPascal Mathematical Functions Curve Fitting Methods CalcParabolFit
See also: CalcCircleFit, CalcReciLinFit, CalcHyperbolFit, CalcPolyFit, CubicSpline, CalcCenteredPolyFit, CalcExponentialFit 

CalcParabolFit

Declaration:TCurveFit.CalcParabolFit (var k0,k1,k2: Double; var FitQual: Double);
The procedure CalcParabolFit calculates the best fitting parabola for a given set of data. The parabola is determined by the equation

The values of x and y are given by the data samples, the parameters k0, k1, and k2 are estimated by CalcParabolFit 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 CalcParabolFit. Do not forget to reset the statistics calculation before entering any new datasets (use the method Init). In addition to the parameters k0, k1, and k2, CalcParabolFit returns the goodness of fit FitQual. This parameter may vary between 0.0 and 1.0, indicating the best possible fit if FitQual equals 1.0.

Hint: The quality of fit calculated by CalcParabolFit is not adjusted for the degree of freedoms in the regression parameters.