micycle.pgs.commons

Class MinimumBoundingEllipse

java.lang.Object

micycle.pgs.commons.MinimumBoundingEllipse

public class MinimumBoundingEllipse
extends Object

Minimum Volume Enclosing Ellipsoid

Author:

Peter Borissow

Constructor Summary

Constructors

Constructor and Description
MinimumBoundingEllipse(double[][] points, double tolerance) Khachiyan’s Algorithm for the Computation of Minimum Volume Enclosing Ellipsoids.

Method Summary

Modifier and Type	Method and Description
double[][]	getBoundingCoordinates(int numPoints) Returns a list of coordinates that can be used to render the ellipse.
double[]	getCenter() Returns the center point of the ellipse
double[][]	getMatrix() Returns a matrix containing all the information regarding the shape of the ellipsoid.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MinimumBoundingEllipse

public MinimumBoundingEllipse(double[][] points,
                              double tolerance)

Khachiyan’s Algorithm for the Computation of Minimum Volume Enclosing Ellipsoids.

Parameters:

points - An array of points. Each entry in the array contains an x,y coordinate. The points must form a closed loop. Consider pre-processing a geometry to find its convex hull, and supply thos coordinates to compute the MBE.

tolerance - the error tolerance to use when terminating optimisation. 0.001 to 0.01 recommended.

Method Detail

getCenter

public double[] getCenter()

Returns the center point of the ellipse

Returns:

double[2] containing center x and y coordinates

getMatrix

public double[][] getMatrix()

Returns a matrix containing all the information regarding the shape of the ellipsoid. To get the radii and orientation of the ellipsoid take the Singular Value Decomposition of the matrix.

getBoundingCoordinates

public double[][] getBoundingCoordinates(int numPoints)

Returns a list of coordinates that can be used to render the ellipse.

Parameters:

numPoints - The number of points used to represent the ellipse. The higher the number the more dense the ellipse outline, the more accurate the shape.