conicfit (version 1.0.4)

fit.ellipseLMG: Fitting an ellipse using Implicit method

Description

fit.ellipseLMG Fits an ellipse to a given set of points (Implicit method) using geometric parameters. Conic:

Usage

fit.ellipseLMG(XY,ParGini,LambdaIni = 1, epsilon = 1e-06, IterMAX = 200,
L = 200)

Arguments

XY

array of sample data

ParGini

initial parameter vector c(Center(1:2), Axes(1:2), Angle)

LambdaIni

initial value of the control parameter Lambda

epsilon

tolerance (small threshold)

IterMAX

maximum number of (main) iterations, usually 10-20 will suffice

L

boundary for major/minor axis

Value

list(ParG,RSS,iters,TF)

list with geometric parameters (A,B,C,D,E,F), Residual Sum of Squares, number of iterations and TF==TRUE if the method diverges

Source

Nikolai Chernov, 2014 Fitting ellipses, circles, and lines by least squares http://people.cas.uab.edu/~mosya/cl/ N. Chernov, Q. Huang, and H. Ma, 2014 Fitting quadratic curves to data points British Journal of Mathematics & Computer Science, 4, 33-60. N. Chernov and H. Ma, 2011 Least squares fitting of quadratic curves and surfaces In: Computer Vision, Editor S. R. Yoshida, Nova Science Publishers; pp. 285-302.

References

Nikolai Chernov, 2014 Fitting ellipses, circles, and lines by least squares http://people.cas.uab.edu/~mosya/cl/

N. Chernov, Q. Huang, and H. Ma, 2014 Fitting quadratic curves to data points British Journal of Mathematics & Computer Science, 4, 33-60.

N. Chernov and H. Ma, 2011 Least squares fitting of quadratic curves and surfaces In: Computer Vision, Editor S. R. Yoshida, Nova Science Publishers; pp. 285-302.

Examples

XY <- matrix(c(1,7,2,6,5,8,7,7,9,5,3,7,6,2,8,4),8,2,byrow=TRUE)
ParGini <- matrix(c(0,0,2,1,0),ncol=1)
LambdaIni=0.1
fit.ellipseLMG(XY,ParGini,LambdaIni)