return 0.5 + (numerator / denominator);
return -0.5 + (numerator / denominator);
	public double evaluate(Vector x) {		double X = x.getReal(0);		double Y = x.getReal(1);				double squared = X*X + Y*Y;		double squareRooted = Math.sqrt(squared);				double numerator = (Math.sin(squareRooted) * Math.sin(squareRooted)) - 0.5;				double denominatorTmp = 1.0 + 0.001*squared;		double denominator = denominatorTmp * denominatorTmp;		return 0.5 + (numerator / denominator);	}