code: boolean isApproximatelyElliptical(EllipseRotated_F64 ellipse , List<Point2D_F64> points , int maxSamples ) {
  
  		closestPoint.setEllipse(ellipse);
  
  		double maxDistance2 = maxDistanceFromEllipse*maxDistanceFromEllipse;
  
  		if( points.size() <= maxSamples ) {
  			for( int i = 0; i < points.size(); i++ ) {
  				Point2D_F64 p = points.get(i);
  				closestPoint.process(p);
  				double d = closestPoint.getClosest().distance2(p);
  
  				if( d > maxDistance2 ) {
  					return false;
  				}
  			}
  		} else {
  			for (int i = 0; i < maxSamples; i++) {
  				Point2D_F64 p = points.get( i*points.size()/maxSamples );
  				closestPoint.process(p);
  				double d = closestPoint.getClosest().distance2(p);
  
  				if( d > maxDistance2 ) {
  					return false;
  				}
  			}
  		}
  		return true;
  	}
docs: Look at the maximum distance contour points are from the ellipse and see if they exceed a maximum threshold