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/data/doxygen/doxygen-1.7.3/gen/CMSSW_4_2_8/src/TrackingTools/TrajectoryState/src/TrajectoryStateClosestToPoint.cc

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00001 #include "TrackingTools/TrajectoryState/interface/TrajectoryStateClosestToPoint.h"
00002 #include "FWCore/MessageLogger/interface/MessageLogger.h"
00003 
00004 // Private constructor
00005 
00006 TrajectoryStateClosestToPoint::
00007 TrajectoryStateClosestToPoint(const FTS& originalFTS, const GlobalPoint& referencePoint) :
00008   valid(true), theFTS(originalFTS), theFTSavailable(true), theRefPoint(referencePoint)
00009 {
00010   try {
00011       theParameters = perigeeConversions.ftsToPerigeeParameters(originalFTS, referencePoint, thePt);
00012       if (theFTS.hasError()) {
00013         thePerigeeError = perigeeConversions.ftsToPerigeeError(originalFTS);
00014         errorIsAvailable = true;
00015       } 
00016       else {
00017         errorIsAvailable = false;
00018       }
00019       theField = &(originalFTS.parameters().magneticField());
00020   } catch (const cms::Exception &ex) {
00021       if (ex.category() != "PerigeeConversions") throw;
00022       edm::LogWarning("TrajectoryStateClosestToPoint_PerigeeConversions") << "Caught exception " << ex.explainSelf() << ".\n";
00023       valid = false;
00024   }
00025 }
00026 
00027 
00034 TrajectoryStateClosestToPoint::
00035 TrajectoryStateClosestToPoint(const PerigeeTrajectoryParameters& perigeeParameters, double pt,
00036   const GlobalPoint& referencePoint, const MagneticField* field) :
00037     valid(true), theField(field), theFTSavailable(false), theRefPoint(referencePoint), 
00038     theParameters(perigeeParameters), thePt( pt ), errorIsAvailable(false)
00039 {}
00040 
00047 TrajectoryStateClosestToPoint::
00048 TrajectoryStateClosestToPoint(const PerigeeTrajectoryParameters& perigeeParameters, double pt,
00049   const PerigeeTrajectoryError& perigeeError, const GlobalPoint& referencePoint,
00050   const MagneticField* field):
00051     valid(true), theField(field), theFTSavailable(false), theRefPoint(referencePoint),
00052     theParameters(perigeeParameters), thePt( pt ), thePerigeeError(perigeeError),
00053     errorIsAvailable(true)
00054     
00055 {}
00056 
00057 
00058 void TrajectoryStateClosestToPoint::calculateFTS() const
00059 {
00060   if(!isValid()) throw TrajectoryStateException(
00061         "TrajectoryStateClosestToPoint is invalid and cannot return any parameters");
00062   GlobalTrajectoryParameters gtp(
00063             perigeeConversions.positionFromPerigee(theParameters, theRefPoint),
00064             perigeeConversions.momentumFromPerigee(theParameters, thePt, theRefPoint),
00065             theParameters.charge(), theField);
00066   if (errorIsAvailable) {
00067     theFTS = FTS(gtp, perigeeConversions.curvilinearError(thePerigeeError, gtp));
00068   } else {
00069     theFTS = FTS(gtp);
00070   }
00071   theFTSavailable = true;
00072 }