#include <JacobianLocalToCurvilinear.h>

Public Member Functions
const AlgebraicMatrix55 &	jacobian () const

	JacobianLocalToCurvilinear (const Surface &surface, const LocalTrajectoryParameters &localParameters, const GlobalTrajectoryParameters &globalParameters, const MagneticField &magField)

	JacobianLocalToCurvilinear (const Surface &surface, const LocalTrajectoryParameters &localParameters, const MagneticField &magField)

Private Member Functions
void	compute (Surface::RotationType const &rot, LocalVector const &tnl, GlobalVector const &tn, GlobalVector const &hq)

Private Attributes
AlgebraicMatrix55	theJacobian

Detailed Description

Class which calculates the Jacobian matrix of the transformation from the local to the curvilinear frame. The Jacobian is calculated during construction and thereafter cached, enabling reuse of the same Jacobian without calculating it again.

Definition at line 21 of file JacobianLocalToCurvilinear.h.

Constructor & Destructor Documentation

◆ JacobianLocalToCurvilinear() [1/2]

JacobianLocalToCurvilinear::JacobianLocalToCurvilinear	(	const Surface &	surface,
		const LocalTrajectoryParameters &	localParameters,
		const MagneticField &	magField
	)

Constructor from local trajectory parameters and surface defining the local frame. NB!! No default constructor exists!

Definition at line 8 of file JacobianLocalToCurvilinear.cc.

     : theJacobian(ROOT::Math::SMatrixNoInit()) {
   GlobalPoint x = surface.toGlobal(localParameters.position());
   GlobalVector h = magField.inInverseGeV(x);
   GlobalVector hq = h * localParameters.signedInverseMomentum();  // changed sign
  
   LocalVector tnl = localParameters.direction();
   GlobalVector tn = surface.toGlobal(tnl);
  
   Surface::RotationType const& rot = surface.rotation();
  
   compute(rot, tnl, tn, hq);
 }

References compute(), LocalTrajectoryParameters::direction(), MagneticField::inInverseGeV(), LocalTrajectoryParameters::position(), makeMuonMisalignmentScenario::rot, GloballyPositioned< T >::rotation(), LocalTrajectoryParameters::signedInverseMomentum(), Surface::toGlobal(), and x.

◆ JacobianLocalToCurvilinear() [2/2]

JacobianLocalToCurvilinear::JacobianLocalToCurvilinear	(	const Surface &	surface,
		const LocalTrajectoryParameters &	localParameters,
		const GlobalTrajectoryParameters &	globalParameters,
		const MagneticField &	magField
	)

Constructor from local and global trajectory parameters and surface defining the local frame.

Definition at line 24 of file JacobianLocalToCurvilinear.cc.

     : theJacobian(ROOT::Math::SMatrixNoInit()) {
   GlobalVector h = globalParameters.magneticFieldInInverseGeV();
   GlobalVector hq = h * localParameters.signedInverseMomentum();  // changed sign
  
   LocalVector tnl = localParameters.direction();
   GlobalVector tn = surface.toGlobal(tnl);  // globalParameters.momentum().unit();
  
   Surface::RotationType const& rot = surface.rotation();
  
   compute(rot, tnl, tn, hq);
 }

References compute(), LocalTrajectoryParameters::direction(), GlobalTrajectoryParameters::magneticFieldInInverseGeV(), makeMuonMisalignmentScenario::rot, GloballyPositioned< T >::rotation(), LocalTrajectoryParameters::signedInverseMomentum(), and Surface::toGlobal().

Member Function Documentation

◆ compute()

void JacobianLocalToCurvilinear::compute	(	Surface::RotationType const &	rot,
		LocalVector const &	tnl,
		GlobalVector const &	tn,
		GlobalVector const &	hq
	)

private

Definition at line 40 of file JacobianLocalToCurvilinear.cc.

                                                                  {
   // Origin: TRSDSC
  
   GlobalVector dj(rot.x());
   GlobalVector dk(rot.y());
  
   // rotate coordinates because of wrong coordinate system in orca
   double tvwX = tnl.z(), tvwY = tnl.x(), tvwZ = tnl.y();
   double cosl = tn.perp();
   if (cosl < 1.e-30)
     cosl = 1.e-30;
   double cosl1 = 1. / cosl;
  
   GlobalVector un(-tn.y() * cosl1, tn.x() * cosl1, 0.);
   double uj = un.dot(dj);
   double uk = un.dot(dk);
   double sinz = -un.dot(hq);
  
   GlobalVector vn(-tn.z() * un.y(), tn.z() * un.x(), cosl);
   double vj = vn.dot(dj);
   double vk = vn.dot(dk);
   double cosz = vn.dot(hq);
  
   theJacobian(0, 0) = 1.;
   for (auto i = 1; i < 5; ++i)
     theJacobian(0, i) = 0.;
  
   theJacobian(1, 0) = 0.;
   theJacobian(2, 0) = 0.;
  
   theJacobian(1, 1) = tvwX * vj;
   theJacobian(1, 2) = tvwX * vk;
   theJacobian(2, 1) = tvwX * uj * cosl1;
   theJacobian(2, 2) = tvwX * uk * cosl1;
  
   for (auto i = 0; i < 3; ++i) {
     theJacobian(3, i) = 0.;
     theJacobian(4, i) = 0.;
   }
  
   theJacobian(3, 3) = uj;
   theJacobian(3, 4) = uk;
   theJacobian(4, 3) = vj;
   theJacobian(4, 4) = vk;
  
   theJacobian(1, 3) = tvwY * sinz;
   theJacobian(1, 4) = tvwZ * sinz;
   theJacobian(2, 3) = tvwY * (cosz * cosl1);
   theJacobian(2, 4) = tvwZ * (cosz * cosl1);
   // end of TRSDSC
  
   //dbg::dbg_trace(1,"Loc2Cu", localParameters.vector(),x,dj,dk,theJacobian);
 }