#include <JacobianLocalToCartesian.h>

Public Member Functions
const AlgebraicMatrix65 &	jacobian () const

	JacobianLocalToCartesian (const Surface &surface, const LocalTrajectoryParameters &localParameters)

Private Attributes
AlgebraicMatrix65	theJacobian

Detailed Description

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

Definition at line 16 of file JacobianLocalToCartesian.h.

Constructor & Destructor Documentation

JacobianLocalToCartesian::JacobianLocalToCartesian	(	const Surface &	surface,
		const LocalTrajectoryParameters &	localParameters
	)

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

Definition at line 5 of file JacobianLocalToCartesian.cc.

References LocalTrajectoryParameters::charge(), BeamSpotFakeParameters_cfi::dxdz, LocalTrajectoryParameters::dxdz(), BeamSpotFakeParameters_cfi::dydz, LocalTrajectoryParameters::dydz(), LocalTrajectoryParameters::pzSign(), lumiQueryAPI::q, LocalTrajectoryParameters::qbp(), dttmaxenums::R, makeMuonMisalignmentScenario::rot, GloballyPositioned< T >::rotation(), funct::sqr(), mathSSE::sqrt(), theJacobian, TkRotation< T >::xx(), TkRotation< T >::xy(), TkRotation< T >::xz(), TkRotation< T >::yx(), TkRotation< T >::yy(), TkRotation< T >::yz(), TkRotation< T >::zx(), TkRotation< T >::zy(), and TkRotation< T >::zz().

                                                                    : theJacobian() {
   
   //LocalCoordinates 1 = (x, y, z, px, py, pz)
   //LocalCoordinates 2 = (q/|p|, dx/dz, dy/dz, x, y)
   //Transformation: x  = x
   //                y  = y
   //          px = (q/(q/|p|)) * (dx/dz) *  sqrt(1./(1.+(dx/dz)^2+(dy/dz)^2))
   //          py = (q/(q/|p|)) * (dy/dz) * sqrt(1./(1.+(dx/dz)^2+(dy/dz)^2))
   //          pz = (q/(q/|p|)) * sqrt(1./(1.+(dx/dz)^2+(dy/dz)^2))
   //Jacobian J((x, y, px, py, pz)  = f(q/|p|, dx/dz, dy/dz, x, y))
 
   // AlgebraicVector5 localTrackParams = localParameters.mixedFormatVector();
   double qbp = localParameters.qbp();
   double dxdz = localParameters.dxdz();
   double dydz = localParameters.dydz();
   TrackCharge iq = localParameters.charge();
   // for neutrals: qbp is 1/p instead of q/p - 
   //   equivalent to charge 1
   if ( iq==0 )  iq = 1;
   double pzSign = localParameters.pzSign();
   double q = iq*pzSign;
   double sqr = sqrt(dxdz*dxdz + dydz*dydz + 1);
   double den = -q/(sqr*sqr*sqr*qbp);
 
   // no difference between local and data member
   AlgebraicMatrix65 & lJacobian = theJacobian;
   lJacobian(0,3) = 1.;
   lJacobian(1,4) = 1.;
   lJacobian(3,0) = ( dxdz*(-q/(sqr*qbp*qbp)) ); 
   lJacobian(3,1) = ( q/(sqr*qbp) + (den*dxdz*dxdz) );
   lJacobian(3,2) = ( (den*dxdz*dydz) );
   lJacobian(4,0) = ( dydz*(-q/(sqr*qbp*qbp)) );
   lJacobian(4,1) = ( (den*dxdz*dydz) );
   lJacobian(4,2) = ( q/(sqr*qbp) + (den*dydz*dydz) );
   lJacobian(5,0) = ( -q/(sqr*qbp*qbp) );
   lJacobian(5,1) = ( (den*dxdz) );
   lJacobian(5,2) = ( (den*dydz) );
   
   /*
   GlobalVector g1 = surface.toGlobal(LocalVector(1., 0., 0.));
   GlobalVector g2 = surface.toGlobal(LocalVector(0., 1., 0.));
   GlobalVector g3 = surface.toGlobal(LocalVector(0., 0., 1.));
   */
   AlgebraicMatrix33 Rsub;
   /*
   Rsub(0,0) = g1.x(); Rsub(0,1) = g2.x(); Rsub(0,2) = g3.x();
   Rsub(1,0) = g1.y(); Rsub(1,1) = g2.y(); Rsub(1,2) = g3.y();
   Rsub(2,0) = g1.z(); Rsub(2,1) = g2.z(); Rsub(2,2) = g3.z();
   */
   // need to be copied anhhow to go from float to double...
   Surface::RotationType const & rot = surface.rotation();
   Rsub(0,0) = rot.xx(); Rsub(0,1) = rot.yx(); Rsub(0,2) = rot.zx();
   Rsub(1,0) = rot.xy(); Rsub(1,1) = rot.yy(); Rsub(1,2) = rot.zy();
   Rsub(2,0) = rot.xz(); Rsub(2,1) = rot.yz(); Rsub(2,2) = rot.zz();
 
   AlgebraicMatrix66 R;
   R.Place_at(Rsub, 0,0);
   R.Place_at(Rsub, 3,3);
   theJacobian = R * lJacobian;
   //dbg::dbg_trace(1,"Loc2Ca", localParameters.vector(),g1,g2,g3,theJacobian);
 }