function calcNURBSDerivatives( p, U, P, u, nd ) {

	const Pders = calcBSplineDerivatives( p, U, P, u, nd );
	return calcRationalCurveDerivatives( Pders );

}
Calculates NURBS curve derivatives. See The NURBS Book, page 127, algorithm A4.2.

@param {number} p - The degree.
@param {Array<number>} U - The knot vector.
@param {Array<Vector4>} P - The control points in homogeneous space.
@param {number} u - The parametric point.
@param {number} nd - The number of derivatives.
@return {Array<Vector3>} array with derivatives for rational curve.