CMSSW Reference Manual

CartesianState RK4OneStep::operator()	(	const CartesianState &	start,
		const RKCartesianDerivative &	deriv,
		double	step
	)			const

Definition at line 7 of file RK4OneStep.cc.

References HLT_VtxMuL3::result.

00009 {
00010   double s0 = 0; // derivatives do't depend on absolute value of the integration variable
00011   CartesianState k1 = step * deriv( s0, start);
00012   CartesianState k2 = step * deriv( s0+step/2, start+k1/2);
00013   CartesianState k3 = step * deriv( s0+step/2, start+k2/2);
00014   CartesianState k4 = step * deriv( s0+step, start+k3);
00015 /*
00016   std::cout << "k1 = " << k1.position() << k1.momentum() << std::endl;
00017   std::cout << "k2 = " << k2.position() << k2.momentum() << std::endl;
00018   std::cout << "k3 = " << k3.position() << k3.momentum() << std::endl;
00019   std::cout << "k4 = " << k4.position() << k4.momentum() << std::endl;
00020 */
00021   CartesianState result = start + k1/6 + k2/3 + k3/3 + k4/6;
00022   return result;
00023 }

RK4OneStep Class Reference

Public Member Functions

Detailed Description

Member Function Documentation


Public Member Functions
CartesianState	operator() (const CartesianState &start, const RKCartesianDerivative &deriv, double step) const