ecal::EcalMipTrackingProcessor Class Reference

Public Types
typedef std::pair< ldmx::EcalID, float >	CellEnergyPair
using	XYCoords = ldmx::XYCoords
using	HitData = ldmx::HitData

Public Member Functions
	EcalMipTrackingProcessor (const std::string &name, framework::Process &process)
void	onNewRun (const ldmx::RunHeader &rh) override
	onNewRun is the first function called for each processor after the conditions are fully configured and accessible.
void	onProcessEnd () override
	Callback for the EventProcessor to take any necessary action when the processing of events finishes, such as calculating job-summary quantities.
void	configure (framework::config::Parameters &parameters) override
	Configure the processor using the given user specified parameters.
void	produce (framework::Event &event) override
	Process the event and put new data products into it.
Public Member Functions inherited from framework::Producer
	Producer (const std::string &name, Process &process)
	Class constructor.
virtual void	process (Event &event) final
	Processing an event for a Producer is calling produce.
Public Member Functions inherited from framework::EventProcessor
	DECLARE_FACTORY (EventProcessor, EventProcessor *, const std::string &, Process &)
	declare that we have a factory for this class
	EventProcessor (const std::string &name, Process &process)
	Class constructor.
virtual	~EventProcessor ()=default
	Class destructor.
virtual void	beforeNewRun (ldmx::RunHeader &run_header)
	Callback for Producers to add parameters to the run header before conditions are initialized.
virtual void	onFileOpen (EventFile &event_file)
	Callback for the EventProcessor to take any necessary action when a new event input ROOT file is opened.
virtual void	onFileClose (EventFile &event_file)
	Callback for the EventProcessor to take any necessary action when a event input ROOT file is closed.
virtual void	onProcessStart ()
	Callback for the EventProcessor to take any necessary action when the processing of events starts, such as creating histograms.
template<class T >
const T &	getCondition (const std::string &condition_name)
	Access a conditions object for the current event.
TDirectory *	getHistoDirectory ()
	Access/create a directory in the histogram file for this event processor to create histograms and analysis tuples.
void	setStorageHint (framework::StorageControl::Hint hint)
	Mark the current event as having the given storage control hint from this module_.
void	setStorageHint (framework::StorageControl::Hint hint, const std::string &purposeString)
	Mark the current event as having the given storage control hint from this module and the given purpose string.
int	getLogFrequency () const
	Get the current logging frequency from the process.
int	getRunNumber () const
	Get the run number from the process.
std::string	getName () const
	Get the processor name.
void	createHistograms (const std::vector< framework::config::Parameters > &histos)
	Internal function which is used to create histograms passed from the python configuration @parma histos vector of Parameters that configure histograms to create.

Private Member Functions
void	clearProcessor ()

Private Attributes
int	nevents_ {0}
double	processing_time_ {0.}
std::map< std::string, double >	profiling_map_
double	linreg_radius_ {0}
int	n_ecal_layers_ {0}
int	n_readout_hits_ {0}
int	n_straight_tracks_ {0}
	Number of "straight" tracks found in the event.
int	n_linreg_tracks_ {0}
	Number of "linreg" tracks found in the event.
int	first_near_ph_layer_ {0}
	Earliest ECal layer in which a hit is found near the projected photon trajectory.
int	n_near_ph_hits_ {0}
	Number of hits near the photon trajectory.
int	photon_territory_hits_ {0}
	Number of hits in the photon territory.
std::string	ecal_collection_name_ {"EcalVeto"}
std::string	ecal_pass_name_ {""}
std::string	mip_collection_name_ {"EcalTrajectoryInfo"}
std::string	mip_pass_name_ {""}
std::string	mip_result_name_ {"EcalMipResult"}
const ldmx::EcalGeometry *	geometry_
	handle to current geometry (to share with member functions)

Additional Inherited Members
Protected Member Functions inherited from framework::EventProcessor
void	abortEvent ()
	Abort the event immediately.
Protected Attributes inherited from framework::EventProcessor
HistogramPool	histograms_
	helper object for making and filling histograms
NtupleManager &	ntuple_ {NtupleManager::getInstance()}
	Manager for any ntuples.
logging::logger	the_log_
	The logger for this EventProcessor.

Detailed Description

Definition at line 24 of file EcalMipTrackingProcessor.h.

Member Typedef Documentation

CellEnergyPair

std::pair<ldmx::EcalID, float> ecal::EcalMipTrackingProcessor::CellEnergyPair

Definition at line 26 of file EcalMipTrackingProcessor.h.

HitData

using ecal::EcalMipTrackingProcessor::HitData = ldmx::HitData

Definition at line 57 of file EcalMipTrackingProcessor.h.

XYCoords

using ecal::EcalMipTrackingProcessor::XYCoords = ldmx::XYCoords

Definition at line 28 of file EcalMipTrackingProcessor.h.

Constructor & Destructor Documentation

EcalMipTrackingProcessor()

ecal::EcalMipTrackingProcessor::EcalMipTrackingProcessor ( const std::string & name, framework::Process & process )

inline

Definition at line 30 of file EcalMipTrackingProcessor.h.

      : Producer(name, process) {}

Member Function Documentation

clearProcessor()

void ecal::EcalMipTrackingProcessor::clearProcessor ( )

private

Definition at line 33 of file EcalMipTrackingProcessor.cxx.

                                              {
  // MIP tracking
  n_straight_tracks_ = 0;
  n_linreg_tracks_ = 0;
  first_near_ph_layer_ = 0;
  n_near_ph_hits_ = 0;
  photon_territory_hits_ = 0;
}

configure()

void ecal::EcalMipTrackingProcessor::configure ( framework::config::Parameters & parameters )

overridevirtual

Configure the processor using the given user specified parameters.

Parameters

parameters

Set of parameters used to configure this processor.

Reimplemented from framework::EventProcessor.

Definition at line 22 of file EcalMipTrackingProcessor.cxx.

                                           {
  n_ecal_layers_ = parameters.get<int>("num_ecal_layers");
  linreg_radius_ = parameters.get<double>("linreg_radius");
  ecal_collection_name_ = parameters.get<std::string>("ecal_collection_name");
  ecal_pass_name_ = parameters.get<std::string>("ecal_pass_name");
  mip_collection_name_ = parameters.get<std::string>("mip_collection_name");
  mip_pass_name_ = parameters.get<std::string>("mip_pass_name");
  mip_result_name_ = parameters.get<std::string>("mip_result_name");
}

References framework::config::Parameters::get().

onNewRun()

void ecal::EcalMipTrackingProcessor::onNewRun ( const ldmx::RunHeader & rh )

overridevirtual

onNewRun is the first function called for each processor after the conditions are fully configured and accessible.

This is where you could create single-processors, multi-event calculation objects.

Reimplemented from framework::EventProcessor.

Definition at line 16 of file EcalMipTrackingProcessor.cxx.

                                                               {
  profiling_map_["straight_tracks"] = 0.;
  profiling_map_["linreg_tracks"] = 0.;
  profiling_map_["processing_time_"] = 0;
}

onProcessEnd()

void ecal::EcalMipTrackingProcessor::onProcessEnd ( )

overridevirtual

Callback for the EventProcessor to take any necessary action when the processing of events finishes, such as calculating job-summary quantities.

Reimplemented from framework::EventProcessor.

Definition at line 508 of file EcalMipTrackingProcessor.cxx.

                                            {
  ldmx_log(info) << "AVG Time/Event: " << std::fixed << std::setprecision(2)
                 << processing_time_ / nevents_ << " ms";
 
  ldmx_log(info) << "Breakdown::";
 
  ldmx_log(info) << "straight_tracks        Avg Time/Event = " << std::fixed
                 << std::setprecision(3)
                 << profiling_map_["straight_tracks"] / nevents_ << " ms";
 
  ldmx_log(info) << "linreg_tracks        Avg Time/Event = " << std::fixed
                 << std::setprecision(3)
                 << profiling_map_["linreg_tracks"] / nevents_ << " ms";
}

produce()

void ecal::EcalMipTrackingProcessor::produce ( framework::Event & event )

overridevirtual

Process the event and put new data products into it.

Parameters

event

The Event to process.

Implements framework::Producer.

Definition at line 42 of file EcalMipTrackingProcessor.cxx.

                                                            {
  auto start = std::chrono::high_resolution_clock::now();
 
  ldmx::EcalMipResult mip_result;
  clearProcessor();
 
  // Get the Ecal Geometry
  geometry_ = &getCondition<ldmx::EcalGeometry>(
      ldmx::EcalGeometry::CONDITIONS_OBJECT_NAME);
 
  // Read in hits near photon from EcalVetoProcessor
  auto ecal_veto_result = event.getObject<ldmx::EcalVetoResult>(
      ecal_collection_name_, ecal_pass_name_);
  auto ecal_trajectory_info = event.getObject<ldmx::EcalTrajectoryInfo>(
      mip_collection_name_, mip_pass_name_);
  std::vector<XYCoords> ele_trajectory, photon_trajectory,
      ele_trajectory_at_target;
  std::vector<ldmx::HitData> tracking_hit_list;
  ldmx_log(trace) << "EcalMipTrackingProcessor::produce() called";
  ele_trajectory = ecal_trajectory_info.getEleTrajectory();
  photon_trajectory = ecal_trajectory_info.getPhotonTrajectory();
  tracking_hit_list = ecal_trajectory_info.getTrackingHitList();
  n_readout_hits_ = ecal_veto_result.getNReadoutHits();
  nevents_++;
  // Now inputting Lines 753-1178 of the original EcalVetoProcessor
  // ------------------------------------------------------
  // MIP tracking starts here
 
  /* Goal:  Calculate
   *  n_straight_tracks (self-explanatory),
   *  n_linreg_tracks (tracks found by linreg algorithm),
   */
 
  // Find epAng and epSep, and prepare EP trajectory vectors:
  ROOT::Math::XYZVector e_traj_start;
  ROOT::Math::XYZVector e_traj_end;
  ROOT::Math::XYZVector p_traj_start;
  ROOT::Math::XYZVector p_traj_end;
  if (!ele_trajectory.empty() && !photon_trajectory.empty()) {
    // Create TVector3s marking the start and endpoints of each projected
    // trajectory
    e_traj_start.SetXYZ(ele_trajectory[0].first, ele_trajectory[0].second,
                        geometry_->getZPosition(0));
    e_traj_end.SetXYZ(ele_trajectory[(n_ecal_layers_ - 1)].first,
                      ele_trajectory[(n_ecal_layers_ - 1)].second,
                      geometry_->getZPosition((n_ecal_layers_ - 1)));
    p_traj_start.SetXYZ(photon_trajectory[0].first, photon_trajectory[0].second,
                        geometry_->getZPosition(0));
    p_traj_end.SetXYZ(photon_trajectory[(n_ecal_layers_ - 1)].first,
                      photon_trajectory[(n_ecal_layers_ - 1)].second,
                      geometry_->getZPosition((n_ecal_layers_ - 1)));
  } else {
    // Electron trajectory is missing, so place trajectories far outside the
    // ECal to ensure they don't interfere with tracking.
    e_traj_start = ROOT::Math::XYZVector(999, 999, geometry_->getZPosition(0));
    e_traj_end = ROOT::Math::XYZVector(
        999, 999, geometry_->getZPosition((n_ecal_layers_ - 1)));
    p_traj_start =
        ROOT::Math::XYZVector(1000, 1000, geometry_->getZPosition(0));
    p_traj_end = ROOT::Math::XYZVector(
        1000, 1000, geometry_->getZPosition((n_ecal_layers_ - 1)));
  }
  // Near photon step:  Find the first layer_ of the ECal where a hit near the
  // projected photon trajectory is found Currently unusued pending further
  // study; performance has dropped between v9 and v12. Currently used in
  // segmipBDT
  first_near_ph_layer_ = n_ecal_layers_ - 1;
 
  // If no photon trajectory, leave this at the default (ECal back)
  ldmx_log(trace) << "Finding first near photon layer_";
  if (!photon_trajectory.empty()) {
    for (std::vector<ldmx::HitData>::iterator it = tracking_hit_list.begin();
         it != tracking_hit_list.end(); ++it) {
      float eh_dist =
          sqrt(pow((*it).pos_.X() - photon_trajectory[(*it).layer_].first, 2) +
               pow((*it).pos_.Y() - photon_trajectory[(*it).layer_].second, 2));
      // TODO: this 8.7 should be not hardcoded
      if (eh_dist < 8.7) {
        n_near_ph_hits_++;
        if ((*it).layer_ < first_near_ph_layer_) {
          first_near_ph_layer_ = (*it).layer_;
        }
      }
    }
    ldmx_log(trace) << "First near photon layer_: " << first_near_ph_layer_;
  }
 
  // Territories limited to tracking_hit_list
  ROOT::Math::XYZVector g_toe = (e_traj_start - p_traj_start).Unit();
  // TODO what is this 8.7 here???
  ROOT::Math::XYZVector origin = p_traj_start + 0.5 * 8.7 * g_toe;
  ldmx_log(trace) << "Origin of photon territory: " << origin.X() << ", "
                  << origin.Y() << ", " << origin.Z();
  if (!ele_trajectory.empty()) {
    for (auto& hit_data : tracking_hit_list) {
      ROOT::Math::XYZVector hit_pos = hit_data.pos_;
      ROOT::Math::XYZVector hit_prime = hit_pos - origin;
      if (hit_prime.Dot(g_toe) <= 0) {
        photon_territory_hits_++;
      }
    }
    ldmx_log(trace) << "Photon territory hits: " << photon_territory_hits_;
  } else {
    photon_territory_hits_ = n_readout_hits_;
  }
 
  // ------------------------------------------------------
  // Find straight MIP tracks:
 
  std::sort(
      tracking_hit_list.begin(), tracking_hit_list.end(),
      [](ldmx::HitData ha, ldmx::HitData hb) { return ha.layer_ > hb.layer_; });
  // For merging tracks:  Need to keep track of existing tracks
  // Candidate tracks to merge in will always be in front of the current track
  // (lower z_), so only store the last hit 3-layer_ vector:  each track =
  // vector of 3-tuples (xy+layer_).
  std::vector<std::vector<ldmx::HitData>> track_list;
 
  // print tracking_hit_list
 
  ldmx_log(trace) << "====== Tracking hit list (original) length "
                  << tracking_hit_list.size() << " ======";
  for (int i = 0; i < tracking_hit_list.size(); i++) {
    ldmx_log(trace) << "[" << tracking_hit_list[i].pos_.X() << ", "
                    << tracking_hit_list[i].pos_.Y() << ", "
                    << tracking_hit_list[i].layer_ << "], ";
  }
  ldmx_log(trace) << "====== END OF Tracking hit list ======";
 
  // in v14 minR is 4.17 mm
  // while maxR is 4.81 mm
  float cell_width = 2 * geometry_->getCellMaxR();
  for (int i_hit = 0; i_hit < tracking_hit_list.size(); i_hit++) {
    // list of hit numbers in track (34 = maximum theoretical length)
    int track[34];
    int current_hit{i_hit};
    int track_len{1};
 
    track[0] = i_hit;
 
    // Search for hits to add to the track:
    // repeatedly find hits in the front two layers with same x- & y-positions
    // but since v14 the odd layers are offset, so we allow half a cell_width
    // deviation and then add to track until no more hits are found
    int j_hit = i_hit;
    while (j_hit < tracking_hit_list.size()) {
      if ((tracking_hit_list[j_hit].layer_ ==
               tracking_hit_list[current_hit].layer_ - 1 ||
           tracking_hit_list[j_hit].layer_ ==
               tracking_hit_list[current_hit].layer_ - 2) &&
          std::abs(tracking_hit_list[j_hit].pos_.X() -
                   tracking_hit_list[current_hit].pos_.X()) <=
              0.5 * cell_width &&
          std::abs(tracking_hit_list[j_hit].pos_.Y() -
                   tracking_hit_list[current_hit].pos_.Y()) <=
              0.5 * cell_width) {
        track[track_len] = j_hit;
        track_len++;
        current_hit = j_hit;
      }
      j_hit++;
    }
 
    // Confirm that the track is valid:
    if (track_len < 2) continue;  // Track must contain at least 2 hits
    float closest_e = ecal::distTwoLines(
        tracking_hit_list[track[0]].pos_,
        tracking_hit_list[track[track_len - 1]].pos_, e_traj_start, e_traj_end);
    float closest_p = ecal::distTwoLines(
        tracking_hit_list[track[0]].pos_,
        tracking_hit_list[track[track_len - 1]].pos_, p_traj_start, p_traj_end);
    // Make sure that the track is near the photon trajectory and away from the
    // electron trajectory Details of these constraints may be revised
    if (closest_p > cell_width and closest_e < 2 * cell_width) continue;
    if (track_len < 4 and closest_e > closest_p) continue;
 
    ldmx_log(debug) << "====== After rejection for MIP tracking ======";
    ldmx_log(debug) << "current hit: [" << tracking_hit_list[i_hit].pos_.X()
                    << ", " << tracking_hit_list[i_hit].pos_.Y() << ", "
                    << tracking_hit_list[i_hit].layer_ << "]";
 
    for (int k = 0; k < track_len; k++) {
      ldmx_log(debug) << "track[" << k << "] position = ["
                      << tracking_hit_list[track[k]].pos_.X() << ", "
                      << tracking_hit_list[track[k]].pos_.Y() << ", "
                      << tracking_hit_list[track[k]].layer_ << "]";
    }
 
    // if track found, increment n_straight_tracks and remove all hits in track
    // from future consideration
    if (track_len >= 2) {
      std::vector<ldmx::HitData> temp_track_list;
      int n_remove = 0;
      for (int k_hit = 0; k_hit < track_len; k_hit++) {
        temp_track_list.push_back(tracking_hit_list[track[k_hit] - n_remove]);
        tracking_hit_list.erase(tracking_hit_list.begin() + track[k_hit] -
                                n_remove);
        n_remove++;
      }
      // print tracking_hit_list
 
      ldmx_log(trace) << "====== Tracking hit list (after erase) length "
                      << tracking_hit_list.size() << " ======";
      for (int i = 0; i < tracking_hit_list.size(); i++) {
        ldmx_log(trace) << "[" << tracking_hit_list[i].pos_.X() << ", "
                        << tracking_hit_list[i].pos_.Y() << ", "
                        << tracking_hit_list[i].layer_ << "] ";
      }
      ldmx_log(trace) << "====== END OF Tracking hit list ======";
 
      track_list.push_back(temp_track_list);
      // The *current* hit will have been removed, so i_hit is currently
      // pointing to the next hit. Decrement i_hit so no hits will get skipped
      // by i_hit++
      i_hit--;
    }
  }
 
  ldmx_log(debug) << "Straight tracks found (before merge): "
                  << track_list.size();
 
  for (int i_track = 0; i_track < track_list.size(); i_track++) {
    ldmx_log(trace) << "Track " << i_track << ":";
    for (int i_hit = 0; i_hit < track_list[i_track].size(); i_hit++) {
      ldmx_log(trace) << "  Hit " << i_hit << ": ["
                      << track_list[i_track][i_hit].pos_.X() << ", "
                      << track_list[i_track][i_hit].pos_.Y() << ", "
                      << track_list[i_track][i_hit].layer_ << "]" << std::endl;
    }
  }
 
  // Optional addition:  Merge nearby straight tracks.  Not necessary for veto.
  // Criteria:  consider tail of track.  Merge if head of next track is 1/2
  // layers behind, within 1 cell of xy position.
  ldmx_log(debug) << "Beginning track merging using " << track_list.size()
                  << " tracks";
 
  for (int track_i = 0; track_i < track_list.size(); track_i++) {
    // for each track, check the remainder of the track list for compatible
    // tracks
    std::vector<ldmx::HitData> base_track = track_list[track_i];
    ldmx::HitData tail_hitdata =
        base_track.back();  // xylayer of last hit in track
    ldmx_log(trace) << "  Considering track " << track_i;
    for (int track_j = track_i + 1; track_j < track_list.size(); track_j++) {
      std::vector<ldmx::HitData> checking_track = track_list[track_j];
      if (checking_track.empty()) {
        ldmx_log(error) << "Broken logic: a straight ecal track had no hits in "
                           "it during merge.";
        continue;
      }
      ldmx::HitData head_hitdata = checking_track.front();
      // if 1-2 layers behind, and xy within one cell...
      if ((head_hitdata.layer_ == tail_hitdata.layer_ + 1 ||
           head_hitdata.layer_ == tail_hitdata.layer_ + 2) &&
          pow(pow(head_hitdata.pos_.X() - tail_hitdata.pos_.X(), 2) +
                  pow(head_hitdata.pos_.Y() - tail_hitdata.pos_.Y(), 2),
              0.5) <= cell_width) {
        // ...then append the second track to the first one and delete it
        // NOTE:  TO ADD:  (tracking_hit_list[i_hit].pos_ -
        // tracking_hit_list[j_hit].pos_).R()
        ldmx_log(trace) << "     ** Compatible track found at index_ "
                        << track_j;
        ldmx_log(trace) << "     Tail xylayer: " << head_hitdata.pos_.X() << ","
                        << head_hitdata.pos_.Y() << "," << head_hitdata.layer_;
        ldmx_log(trace) << "     Head xylayer: " << tail_hitdata.pos_.X() << ","
                        << tail_hitdata.pos_.Y() << "," << tail_hitdata.layer_;
        for (int hit_k = 0; hit_k < checking_track.size(); hit_k++) {
          base_track.push_back(track_list[track_j][hit_k]);
        }
        track_list[track_i] = base_track;
        track_list.erase(track_list.begin() + track_j);
        break;
      }
    }
  }
  n_straight_tracks_ = track_list.size();
  // print the track list
  ldmx_log(debug) << "Straight tracks found (after merge): "
                  << n_straight_tracks_;
  for (int track_i = 0; track_i < track_list.size(); track_i++) {
    ldmx_log(debug) << "Track " << track_i << ":";
    for (int hit_i = 0; hit_i < track_list[track_i].size(); hit_i++) {
      ldmx_log(debug) << "  Hit " << hit_i << ": ["
                      << track_list[track_i][hit_i].pos_.X() << ", "
                      << track_list[track_i][hit_i].pos_.Y() << ", "
                      << track_list[track_i][hit_i].layer_ << "]";
    }
  }
 
  auto straight_tracks = std::chrono::high_resolution_clock::now();
  profiling_map_["straight_tracks"] +=
      std::chrono::duration<double, std::milli>(straight_tracks - start)
          .count();
  // ------------------------------------------------------
  // Linreg tracking:
  ldmx_log(info) << "Finding linreg tracks from a total of "
                 << tracking_hit_list.size() << " hits using a radius of "
                 << linreg_radius_ << " mm";
 
  for (int i_hit = 0; i_hit < 0; i_hit++) {
    // for (int i_hit = 0; i_hit < tracking_hit_list.size(); i_hit++) {
    //  Hits being considered at a given time
    std::vector<int> hits_in_region;
    TMatrixD vm(3, 3);
    TMatrixD hdt(3, 3);
    ROOT::Math::XYZVector slope_vec;
    ROOT::Math::XYZVector h_mean;
    ROOT::Math::XYZVector h_point;
    float r_corr_best{0.0};
    // Temp array having 3 potential hits
    int hit_nums[3];
    // From the above which are passing the correlation reqs
    int best_hit_nums[3];
 
    hits_in_region.push_back(i_hit);
    // Find all hits within 2 cells of the primary hit:
    for (int j_hit = 0; j_hit < tracking_hit_list.size(); j_hit++) {
      // Dont try to put hits on the same layer_ to the lin-reg track
      if (tracking_hit_list[i_hit].pos_.Z() ==
          tracking_hit_list[j_hit].pos_.Z()) {
        continue;
      }
      float dist_to_hit =
          (tracking_hit_list[i_hit].pos_ - tracking_hit_list[j_hit].pos_).R();
      // This distance optimized to give the best significance
      // it used to be 2*cell_width, i.e. 4.81 mm
      // note, the layers in the back have a separation of 22.3
      if (dist_to_hit <= 2 * linreg_radius_) {
        hits_in_region.push_back(j_hit);
      }
    }
    // Found a track that passed the lin-reg reqs
    bool best_lin_reg_found{false};
 
    ldmx_log(debug) << "There are " << hits_in_region.size()
                    << " hits within a radius of " << linreg_radius_ << " mm";
    // Look at combinations of hits within the region (do not consider the same
    // combination twice):
    hit_nums[0] = i_hit;
    for (int j_hit_in_reg = 1; j_hit_in_reg < hits_in_region.size() - 1;
         j_hit_in_reg++) {
      // We require (exactly) 3 hits for the lin-reg track building
      if (hits_in_region.size() < 3) break;
      hit_nums[1] = hits_in_region[j_hit_in_reg];
      for (int k_hit_reg = j_hit_in_reg + 1; k_hit_reg < hits_in_region.size();
           k_hit_reg++) {
        hit_nums[2] = hits_in_region[k_hit_reg];
        const auto& p0 = tracking_hit_list[hit_nums[0]].pos_;
        const auto& p1 = tracking_hit_list[hit_nums[1]].pos_;
        const auto& p2 = tracking_hit_list[hit_nums[2]].pos_;
 
        h_mean = (p0 + p1 + p2) / 3.0;
 
        double p_arr[3][3] = {{p0.X(), p0.Y(), p0.Z()},
                              {p1.X(), p1.Y(), p1.Z()},
                              {p2.X(), p2.Y(), p2.Z()}};
 
        // Compute mean in an indexable array
        double mean_arr[3] = {(p0.X() + p1.X() + p2.X()) / 3.0,
                              (p0.Y() + p1.Y() + p2.Y()) / 3.0,
                              (p0.Z() + p1.Z() + p2.Z()) / 3.0};
 
        for (int h_ind = 0; h_ind < 3; ++h_ind) {
          for (int l_ind = 0; l_ind < 3; ++l_ind) {
            hdt(h_ind, l_ind) = p_arr[h_ind][l_ind] - mean_arr[l_ind];
          }
        }
 
        // Perform "linreg" on selected points
        // Calculate the determinant of the matrix
        double determinant =
            hdt(0, 0) * (hdt(1, 1) * hdt(2, 2) - hdt(1, 2) * hdt(2, 1)) -
            hdt(0, 1) * (hdt(1, 0) * hdt(2, 2) - hdt(1, 2) * hdt(2, 0)) +
            hdt(0, 2) * (hdt(1, 0) * hdt(2, 1) - hdt(1, 1) * hdt(2, 0));
        // Exit early if the matrix is singular (i.e. det = 0)
        if (determinant == 0) continue;
        // Perform matrix decomposition with SVD
        TDecompSVD svd_obj(hdt);
        bool decomposed = svd_obj.Decompose();
        if (!decomposed) continue;
 
        // First col of V matrix is the slope of the best-fit line
        vm = svd_obj.GetV();
        slope_vec.SetX(vm[0][0]);
        slope_vec.SetY(vm[0][1]);
        slope_vec.SetZ(vm[0][2]);
        // h_mean, h_point are points on the best-fit line
        h_point = slope_vec + h_mean;
        // linreg complete:  Now have best-fit line for 3 hits under
        // consideration Check whether the track is valid:  r^2 must be high,
        // and the track must plausibly originate from the photon
        float closest_e =
            ecal::distTwoLines(h_mean, h_point, e_traj_start, e_traj_end);
        float closest_p =
            ecal::distTwoLines(h_mean, h_point, p_traj_start, p_traj_end);
        // Projected track must be close to the photon; details may change after
        // future study.
        if (closest_p > cell_width or closest_e < 1.5 * cell_width) continue;
        // find r^2
        // ~variance
        float vrnc = (tracking_hit_list[hit_nums[0]].pos_ - h_mean).R() +
                     (tracking_hit_list[hit_nums[1]].pos_ - h_mean).R() +
                     (tracking_hit_list[hit_nums[2]].pos_ - h_mean).R();
        // sum of |errors|
        float sumerr = ecal::distPtToLine(tracking_hit_list[hit_nums[0]].pos_,
                                          h_mean, h_point) +
                       ecal::distPtToLine(tracking_hit_list[hit_nums[1]].pos_,
                                          h_mean, h_point) +
                       ecal::distPtToLine(tracking_hit_list[hit_nums[2]].pos_,
                                          h_mean, h_point);
        float r_corr = 1 - sumerr / vrnc;
        // Check whether r^2 exceeds a low minimum r_corr:  "Fake" tracks are
        // still much more common in background, so making the algorithm
        // oversensitive doesn't lower performance significantly
        if (r_corr > r_corr_best and r_corr > .6) {
          r_corr_best = r_corr;
          // Only looking for 3-hit tracks currently
          best_lin_reg_found = true;
          for (int k = 0; k < 3; k++) {
            best_hit_nums[k] = hit_nums[k];
          }
        }
      }  // end loop on hits in the region
    }  // end 2nd loop on hits in the region
 
    // Continue early if not hits on track
    if (!best_lin_reg_found) continue;
    // Otherwise increase the number of lin-reg tracks
    n_linreg_tracks_++;
    ldmx_log(debug) << " Lin-reg track " << n_linreg_tracks_;
    for (int final_hit_index = 0; final_hit_index < 3; final_hit_index++) {
      ldmx_log(debug)
          << "   Hit " << final_hit_index << " ["
          << tracking_hit_list[best_hit_nums[final_hit_index]].pos_.X() << ", "
          << tracking_hit_list[best_hit_nums[final_hit_index]].pos_.Y() << ", "
          << tracking_hit_list[best_hit_nums[final_hit_index]].pos_.Z() << "] ";
    }
 
    // Exclude all hits in a found track from further consideration:
    for (int l_hit = 0; l_hit < 3; l_hit++) {
      tracking_hit_list.erase(tracking_hit_list.begin() + best_hit_nums[l_hit]);
    }
    i_hit--;
  }  // end loop on all hits
  ldmx_log(info) << " MIP tracking completed; found " << n_straight_tracks_
                 << " straight tracks and " << n_linreg_tracks_
                 << " lin-reg tracks";
 
  auto linreg_tracks = std::chrono::high_resolution_clock::now();
  profiling_map_["linreg_tracks"] +=
      std::chrono::duration<double, std::milli>(linreg_tracks - straight_tracks)
          .count();
 
  mip_result.setVariables(n_straight_tracks_, n_linreg_tracks_,
                          first_near_ph_layer_, n_near_ph_hits_,
                          photon_territory_hits_);
 
  event.add(mip_result_name_, mip_result);
 
  auto end = std::chrono::high_resolution_clock::now();
  auto time_diff = end - start;
  processing_time_ +=
      std::chrono::duration<double, std::milli>(time_diff).count();
}

References ecal::distPtToLine(), ecal::distTwoLines(), first_near_ph_layer_, geometry_, ldmx::EcalGeometry::getCellMaxR(), framework::EventProcessor::getCondition(), ldmx::EcalGeometry::getZPosition(), n_linreg_tracks_, n_near_ph_hits_, n_straight_tracks_, and photon_territory_hits_.

Member Data Documentation

ecal_collection_name_

std::string ecal::EcalMipTrackingProcessor::ecal_collection_name_ {"EcalVeto"}

private

Definition at line 86 of file EcalMipTrackingProcessor.h.

{"EcalVeto"};

ecal_pass_name_

std::string ecal::EcalMipTrackingProcessor::ecal_pass_name_ {""}

private

Definition at line 87 of file EcalMipTrackingProcessor.h.

{""};

first_near_ph_layer_

int ecal::EcalMipTrackingProcessor::first_near_ph_layer_ {0}

private

Earliest ECal layer in which a hit is found near the projected photon trajectory.

Definition at line 80 of file EcalMipTrackingProcessor.h.

{0};

Referenced by produce().

geometry_

const ldmx::EcalGeometry* ecal::EcalMipTrackingProcessor::geometry_

private

handle to current geometry (to share with member functions)

Definition at line 93 of file EcalMipTrackingProcessor.h.

Referenced by produce().

linreg_radius_

double ecal::EcalMipTrackingProcessor::linreg_radius_ {0}

private

Definition at line 68 of file EcalMipTrackingProcessor.h.

{0};

mip_collection_name_

std::string ecal::EcalMipTrackingProcessor::mip_collection_name_ {"EcalTrajectoryInfo"}

private

Definition at line 88 of file EcalMipTrackingProcessor.h.

{"EcalTrajectoryInfo"};

mip_pass_name_

std::string ecal::EcalMipTrackingProcessor::mip_pass_name_ {""}

private

Definition at line 89 of file EcalMipTrackingProcessor.h.

{""};

mip_result_name_

std::string ecal::EcalMipTrackingProcessor::mip_result_name_ {"EcalMipResult"}

private

Definition at line 90 of file EcalMipTrackingProcessor.h.

{"EcalMipResult"};

n_ecal_layers_

int ecal::EcalMipTrackingProcessor::n_ecal_layers_ {0}

private

Definition at line 70 of file EcalMipTrackingProcessor.h.

{0};

n_linreg_tracks_

int ecal::EcalMipTrackingProcessor::n_linreg_tracks_ {0}

private

Number of "linreg" tracks found in the event.

Definition at line 77 of file EcalMipTrackingProcessor.h.

{0};

Referenced by produce().

n_near_ph_hits_

int ecal::EcalMipTrackingProcessor::n_near_ph_hits_ {0}

private

Number of hits near the photon trajectory.

Definition at line 82 of file EcalMipTrackingProcessor.h.

{0};

Referenced by produce().

n_readout_hits_

int ecal::EcalMipTrackingProcessor::n_readout_hits_ {0}

private

Definition at line 71 of file EcalMipTrackingProcessor.h.

{0};

n_straight_tracks_

int ecal::EcalMipTrackingProcessor::n_straight_tracks_ {0}

private

Number of "straight" tracks found in the event.

Definition at line 75 of file EcalMipTrackingProcessor.h.

{0};

Referenced by produce().

nevents_

int ecal::EcalMipTrackingProcessor::nevents_ {0}

private

Definition at line 63 of file EcalMipTrackingProcessor.h.

{0};

photon_territory_hits_

int ecal::EcalMipTrackingProcessor::photon_territory_hits_ {0}

private

Number of hits in the photon territory.

Definition at line 84 of file EcalMipTrackingProcessor.h.

{0};

Referenced by produce().

processing_time_

double ecal::EcalMipTrackingProcessor::processing_time_ {0.}

private

Definition at line 64 of file EcalMipTrackingProcessor.h.

{0.};

profiling_map_

std::map<std::string, double> ecal::EcalMipTrackingProcessor::profiling_map_

private

Definition at line 66 of file EcalMipTrackingProcessor.h.

---

The documentation for this class was generated from the following files:

• Ecal/include/Ecal/EcalMipTrackingProcessor.h
• Ecal/src/Ecal/EcalMipTrackingProcessor.cxx