#include <JacobianCartesianToCurvilinear.h>

Public Member Functions
const AlgebraicMatrix56 &	jacobian () const

	JacobianCartesianToCurvilinear (const GlobalTrajectoryParameters &globalParameters)

Private Attributes
AlgebraicMatrix56	theJacobian

Detailed Description

Class which calculates the Jacobian matrix of the transformation from the Cartesian 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 14 of file JacobianCartesianToCurvilinear.h.

Constructor & Destructor Documentation

JacobianCartesianToCurvilinear::JacobianCartesianToCurvilinear ( const GlobalTrajectoryParameters & globalParameters )

Constructor from global trajectory parameters. NB!! No default constructor exists!

Definition at line 5 of file JacobianCartesianToCurvilinear.cc.

References GlobalTrajectoryParameters::charge(), Vector3DBase< T, FrameTag >::cross(), PV3DBase< T, PVType, FrameType >::mag(), GlobalTrajectoryParameters::momentum(), AlCaHLTBitMon_ParallelJobs::p, p2, p3, PV3DBase< T, PVType, FrameType >::perp(), RecoTauCleanerPlugins::pt, lumiQueryAPI::q, dttmaxenums::R, theJacobian, Vector3DBase< T, FrameTag >::unit(), PV3DBase< T, PVType, FrameType >::x(), PV3DBase< T, PVType, FrameType >::y(), and PV3DBase< T, PVType, FrameType >::z().

                                                                                    : theJacobian() {
   
   GlobalVector xt = globalParameters.momentum();
   //GlobalVector yt(xt.y(), -xt.x(), 0.); \\wrong direction of the axis
   //GlobalVector zt(xt.x()*xt.z(), xt.y()*xt.z(), -xt.perp2()); \\and then also on this one
   GlobalVector yt(-xt.y(), xt.x(), 0.);
   GlobalVector zt = xt.cross(yt);
   GlobalVector pvec = globalParameters.momentum();
   double pt = pvec.perp(), p = pvec.mag();
   double px = pvec.x(), py = pvec.y(), pz = pvec.z();
   double pt2 = pt*pt, p2 = p*p, p3 = p*p*p;
   TrackCharge q = globalParameters.charge();
   // for neutrals: qbp is 1/p instead of q/p - 
   //   equivalent to charge 1
   if ( q==0 )  q = 1;
   xt = xt.unit(); 
   if(fabs(pt) > 0){
     yt = yt.unit(); 
     zt = zt.unit();
   }
   
   AlgebraicMatrix66 R;
   R(0,0) = xt.x(); R(0,1) = xt.y(); R(0,2) = xt.z();
   R(1,0) = yt.x(); R(1,1) = yt.y(); R(1,2) = yt.z();
   R(2,0) = zt.x(); R(2,1) = zt.y(); R(2,2) = zt.z();
   R(3,3) = 1.;
   R(4,4) = 1.;
   R(5,5) = 1.;
 
   theJacobian(0,3) = -q*px/p3;        theJacobian(0,4) = -q*py/p3;        theJacobian(0,5) = -q*pz/p3;
   if(fabs(pt) > 0){
     //theJacobian(1,3) = (px*pz)/(pt*p2); theJacobian(1,4) = (py*pz)/(pt*p2); theJacobian(1,5) = -pt/p2; //wrong sign
     theJacobian(1,3) = -(px*pz)/(pt*p2); theJacobian(1,4) = -(py*pz)/(pt*p2); theJacobian(1,5) = pt/p2;
     theJacobian(2,3) = -py/pt2;         theJacobian(2,4) = px/pt2;          theJacobian(2,5) = 0.;
   }
   theJacobian(3,1) = 1.;
   theJacobian(4,2) = 1.;
   theJacobian = theJacobian * R;
   //dbg::dbg_trace(1,"Ca2Cu", globalParameters.vector(),theJacobian);
 }