Checkpoint

Signed-off-by: Felix Schlepper <felix.schlepper@cern.ch>

Author: f3sch

Detectors/ITSMFT/ITS/tracking/CMakeLists.txt

@@ -16,6 +16,7 @@ o2_add_library(ITStracking
                        src/Configuration.cxx
                        src/FastMultEstConfig.cxx
                        src/FastMultEst.cxx
+                       src/LineVertexerHelpers.cxx
                        src/TimeFrame.cxx
                        src/IOUtils.cxx
                        src/Tracker.cxx

Detectors/ITSMFT/ITS/tracking/include/ITStracking/ClusterLines.h

@@ -14,6 +14,7 @@
 
 #include <array>
 #include <vector>
+#include "gsl/span"
 #include <Math/SMatrix.h>
 #include <Math/SVector.h>
 #include "ITStracking/Cluster.h"
@@ -59,6 +60,7 @@ class ClusterLines final
  public:
   ClusterLines() = default;
   ClusterLines(const int firstLabel, const Line& firstLine, const int secondLabel, const Line& secondLine);
+  ClusterLines(gsl::span<const int> lineLabels, gsl::span<const Line> lines);
   void add(const int lineLabel, const Line& line);
   void computeClusterCentroid();
   void accumulate(const Line& line);
@@ -67,7 +69,7 @@ class ClusterLines final
   const float* getRMS2() const { return mRMS2.Array(); }
   float getAvgDistance2() const { return mAvgDistance2; }
   auto getSize() const noexcept { return mLabels.size(); }
-  auto& getLabels() noexcept { return mLabels; }
+  auto& getLabels() const noexcept { return mLabels; }
   const auto& getTimeStamp() const noexcept { return mTime; }
   bool operator==(const ClusterLines& rhs) const noexcept;
   float getR2() const noexcept { return (mVertex[0] * mVertex[0]) + (mVertex[1] * mVertex[1]); }

Detectors/ITSMFT/ITS/tracking/include/ITStracking/Configuration.h

@@ -18,11 +18,9 @@
 
 #include <cstdint>
 #ifndef GPUCA_GPUCODE_DEVICE
-#include <array>
 #include <limits>
 #include <string>
 #include <vector>
-#include <cmath>
 #endif
 
 #include "DetectorsBase/Propagator.h"
@@ -96,11 +94,10 @@ struct VertexingParameters {
   float pairCut = 0.04f;
   float clusterCut = 0.8f;
   float histPairCut = 0.04f;
-  float tanLambdaCut = 0.002f;     // tanLambda = deltaZ/deltaR
-  float lowMultBeamDistCut = 0.1f; // XY cut for low-multiplicity pile up
-  int vertNsigmaCut = 6;           // N sigma cut for vertex XY
-  float vertRadiusSigma = 0.33f;   // sigma of vertex XY
-  float trackletSigma = 0.01f;     // tracklet to vertex sigma
+  float tanLambdaCut = 0.002f;   // tanLambda = deltaZ/deltaR
+  int vertNsigmaCut = 6;         // N sigma cut for vertex XY
+  float vertRadiusSigma = 0.33f; // sigma of vertex XY
+  float trackletSigma = 0.01f;   // tracklet to vertex sigma
   float maxZPositionAllowed = 25.f;
   int clusterContributorsCut = 16;
   int maxTrackletsPerCluster = 2e3;

Detectors/ITSMFT/ITS/tracking/include/ITStracking/LineVertexerHelpers.h

@@ -0,0 +1,36 @@
+// Copyright 2019-2020 CERN and copyright holders of ALICE O2.
+// See https://alice-o2.web.cern.ch/copyright for details of the copyright holders.
+// All rights not expressly granted are reserved.
+//
+// This software is distributed under the terms of the GNU General Public
+// License v3 (GPL Version 3), copied verbatim in the file "COPYING".
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#ifndef O2_ITS_TRACKING_LINE_VERTEXER_HELPERS_H_
+#define O2_ITS_TRACKING_LINE_VERTEXER_HELPERS_H_
+
+#include <span>
+#include <vector>
+
+#include "ITStracking/ClusterLines.h"
+
+namespace o2::its::line_vertexer
+{
+
+struct Settings {
+  float beamX = 0.f;
+  float beamY = 0.f;
+  float pairCut = 0.f;
+  float pairCut2 = 0.f;
+  float clusterCut = 0.f;
+  float maxZ = 0.f;
+};
+
+std::vector<ClusterLines> buildClusters(std::span<const Line> lines, const Settings& settings);
+
+} // namespace o2::its::line_vertexer
+
+#endif

Detectors/ITSMFT/ITS/tracking/include/ITStracking/MathUtils.h

@@ -94,6 +94,16 @@ GPUhdi() constexpr float Sq(float v)
   return v * v;
 }
 
+GPUhdi() constexpr float SqSum(float v, float w)
+{
+  return Sq(v) + Sq(w);
+}
+
+GPUhdi() constexpr float SqSum(float u, float v, float w)
+{
+  return Sq(u) + SqSum(v, w);
+}
+
 GPUhdi() constexpr float SqDiff(float x, float y)
 {
   return Sq(x - y);

Detectors/ITSMFT/ITS/tracking/include/ITStracking/TrackingConfigParam.h

@@ -33,7 +33,6 @@ struct VertexerParamConfig : public o2::conf::ConfigurableParamHelper<VertexerPa
   float clusterCut = 0.8f;
   float histPairCut = 0.04f;
   float tanLambdaCut = 0.002f;      // tanLambda = deltaZ/deltaR
-  float lowMultBeamDistCut = 0.1f;  // XY cut for low-multiplicity pile up
   int vertNsigmaCut = 4;            // N sigma cut for vertex XY
   float vertRadiusSigma = 0.05f;    // sigma of vertex XY
   float trackletSigma = 0.01f;      // tracklet to vertex sigma

Detectors/ITSMFT/ITS/tracking/src/ClusterLines.cxx

@@ -148,6 +148,38 @@ ClusterLines::ClusterLines(const int firstLabel, const Line& firstLine, const in
   mAvgDistance2 += (Line::getDistance2FromPoint(secondLine, mVertex) - mAvgDistance2) / (float)getSize();
 }
 
+ClusterLines::ClusterLines(gsl::span<const int> lineLabels, gsl::span<const Line> lines)
+{
+  if (lineLabels.size() < 2) {
+    return;
+  }
+
+  mLabels.reserve(lineLabels.size());
+  mTime = lines[lineLabels[0]].mTime;
+  for (size_t index = 0; index < lineLabels.size(); ++index) {
+    const auto lineLabel = lineLabels[index];
+    if (index > 0) {
+      mTime += lines[lineLabel].mTime;
+    }
+    mLabels.push_back(lineLabel);
+    accumulate(lines[lineLabel]);
+  }
+
+  computeClusterCentroid();
+  if (!mIsValid) {
+    return;
+  }
+
+  mRMS2 = Line::getDCAComponents(lines[lineLabels[0]], mVertex);
+  mAvgDistance2 = Line::getDistance2FromPoint(lines[lineLabels[0]], mVertex);
+  for (size_t index = 1; index < lineLabels.size(); ++index) {
+    const auto lineLabel = lineLabels[index];
+    const auto tmpRMS2 = Line::getDCAComponents(lines[lineLabel], mVertex);
+    mRMS2 += (tmpRMS2 - mRMS2) * (1.f / static_cast<float>(index + 1));
+    mAvgDistance2 += (Line::getDistance2FromPoint(lines[lineLabel], mVertex) - mAvgDistance2) / static_cast<float>(index + 1);
+  }
+}
+
 void ClusterLines::add(const int lineLabel, const Line& line)
 {
   mTime += line.mTime;

Detectors/ITSMFT/ITS/tracking/src/Configuration.cxx

@@ -45,8 +45,8 @@ std::string TrackingParameters::asString() const
   }
   if (!AddTimeError.empty()) {
     str += " AddTimeError:";
-    for (size_t i = 0; i < AddTimeError.size(); i++) {
-      str += std::format("{} ", AddTimeError[i]);
+    for (unsigned int i : AddTimeError) {
+      str += std::format("{} ", i);
     }
   }
   if (std::numeric_limits<size_t>::max() != MaxMemory) {
@@ -173,8 +173,8 @@ std::vector<TrackingParameters> TrackingMode::getTrackingParameters(TrackingMode
     LOGP(fatal, "Unsupported ITS tracking mode {} ", toString(mode));
   }
 
-  float bFactor = std::abs(o2::base::Propagator::Instance()->getNominalBz()) / 5.0066791;
-  float bFactorTracklets = bFactor < 0.01 ? 1. : bFactor; // for tracklets only
+  float bFactor = std::abs(o2::base::Propagator::Instance()->getNominalBz()) / 5.0066791f;
+  float bFactorTracklets = bFactor < 0.01f ? 1.f : bFactor; // for tracklets only
 
   // global parameters set for every iteration
   for (auto& p : trackParams) {
@@ -273,7 +273,6 @@ std::vector<VertexingParameters> TrackingMode::getVertexingParameters(TrackingMo
   vertParams[0].vertNsigmaCut = vc.vertNsigmaCut;
   vertParams[0].vertRadiusSigma = vc.vertRadiusSigma;
   vertParams[0].maxTrackletsPerCluster = vc.maxTrackletsPerCluster;
-  vertParams[0].lowMultBeamDistCut = vc.lowMultBeamDistCut;
   vertParams[0].zCut = vc.zCut;
   vertParams[0].phiCut = vc.phiCut;
   vertParams[0].pairCut = vc.pairCut;