code: @Override
  	public void prune() {
  		Iterator<PointIndex<Point>> iter = allPoints.iterator();
  		int index = 0;
  		while( iter.hasNext() ) {
  			iter.next();
  			if (origErrors[index++] >= pruneVal) {
  				iter.remove();
  			}
  		}
  	}
docs: Removes all samples which have an error larger than the specified percentile error.