Package org.hipparchus.geometry.enclosing

Class WelzlEncloser<S extends Space,P extends Point<S>>

java.lang.Object
org.hipparchus.geometry.enclosing.WelzlEncloser<S,P>
Type Parameters:
S - Space type.
P - Point type.
All Implemented Interfaces:
Encloser<S,P>
public class WelzlEncloser<S extends Space,P extends Point<S>> extends Object implements Encloser<S,P>
Class implementing Emo Welzl algorithm to find the smallest enclosing ball in linear time.

The class implements the algorithm described in paper Smallest Enclosing Disks (Balls and Ellipsoids) by Emo Welzl, Lecture Notes in Computer Science 555 (1991) 359-370. The pivoting improvement published in the paper Fast and Robust Smallest Enclosing Balls, by Bernd Gärtner and further modified in paper Efficient Computation of Smallest Enclosing Balls in Three Dimensions by Linus Källberg to avoid performing local copies of data have been included.

  • Constructor Details

    • WelzlEncloser

      public WelzlEncloser(double tolerance, SupportBallGenerator<S,P> generator)
      Simple constructor.
      Parameters:
      tolerance - below which points are consider to be identical
      generator - generator for balls on support

  • Method Details

    • enclose

      public EnclosingBall<S,P> enclose(Iterable<P> points)
      Find a ball enclosing a list of points.
      Specified by:
      enclose in interface Encloser<S extends Space,P extends Point<S>>
      Parameters:
      points - points to enclose
      Returns:
      enclosing ball

    • selectFarthest

      public P selectFarthest(Iterable<P> points, EnclosingBall<S,P> ball)
      Select the point farthest to the current ball.
      Parameters:
      points - points to be enclosed
      ball - current ball
      Returns:
      farthest point