feat: Memory dense MeasurementContainer for Examples

Core/include/Acts/EventData/SubspaceHelpers.hpp

@@ -39,7 +39,7 @@ inline static bool checkSubspaceIndices(const Container& container,
   if (subspaceSize > fullSize) {
     return false;
   }
-  if (container.size() != subspaceSize) {
+  if (static_cast<std::size_t>(container.size()) != subspaceSize) {
     return false;
   }
   for (auto it = container.begin(); it != container.end();) {
@@ -115,6 +115,36 @@ class SubspaceHelperBase {
   auto begin() const { return self().begin(); }
   auto end() const { return self().end(); }
 
+  bool contains(std::uint8_t index) const {
+    return std::find(begin(), end(), index) != end();
+  }
+  std::size_t indexOf(std::uint8_t index) const {
+    auto it = std::find(begin(), end(), index);
+    return it != end() ? std::distance(begin(), it) : kFullSize;
+  }
+
+  template <typename EigenDerived>
+  ActsVector<kFullSize> expandVector(
+      const Eigen::DenseBase<EigenDerived>& vector) const {
+    ActsVector<kFullSize> result = ActsVector<kFullSize>::Zero();
+    for (auto [i, index] : enumerate(*this)) {
+      result(index) = vector(i);
+    }
+    return result;
+  }
+
+  template <typename EigenDerived>
+  FullSquareMatrix expandMatrix(
+      const Eigen::DenseBase<EigenDerived>& matrix) const {
+    FullSquareMatrix result = FullSquareMatrix::Zero();
+    for (auto [i, indexI] : enumerate(*this)) {
+      for (auto [j, indexJ] : enumerate(*this)) {
+        result(indexI, indexJ) = matrix(i, j);
+      }
+    }
+    return result;
+  }
+
   FullSquareMatrix fullProjector() const {
     FullSquareMatrix result = FullSquareMatrix::Zero();
     for (auto [i, index] : enumerate(*this)) {
@@ -168,6 +198,7 @@ class VariableSubspaceHelper
 
   bool empty() const { return m_indices.empty(); }
   std::size_t size() const { return m_indices.size(); }
+  const Container& indices() const { return m_indices; }
 
   IndexType operator[](std::size_t i) const { return m_indices[i]; }
 
@@ -215,6 +246,7 @@ class FixedSubspaceHelper
 
   bool empty() const { return m_indices.empty(); }
   std::size_t size() const { return m_indices.size(); }
+  const Container& indices() const { return m_indices; }
 
   IndexType operator[](std::uint32_t i) const { return m_indices[i]; }
 

Examples/Algorithms/Digitization/include/ActsExamples/Digitization/MeasurementCreation.hpp

@@ -1,6 +1,6 @@
 // This file is part of the Acts project.
 //
-// Copyright (C) 2021 CERN for the benefit of the Acts project
+// Copyright (C) 2021-2024 CERN for the benefit of the Acts project
 //
 // This Source Code Form is subject to the terms of the Mozilla Public
 // License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -40,9 +40,10 @@ struct DigitizedParameters {
 ///
 /// To be used also by the e I/O system
 ///
-/// @return a variant measurement
-Measurement createMeasurement(const DigitizedParameters& dParams,
-                              const IndexSourceLink& isl) noexcept(false);
+/// @return the measurement proxy
+ActsExamples::VariableBoundMeasurementProxy createMeasurement(
+    MeasurementContainer& container, const DigitizedParameters& dParams,
+    const IndexSourceLink& isl) noexcept(false);
 
 /// Construct the constituents of a measurement.
 ///

Examples/Algorithms/Digitization/src/DigitizationAlgorithm.cpp

@@ -1,6 +1,6 @@
 // This file is part of the Acts project.
 //
-// Copyright (C) 2021 CERN for the benefit of the Acts project
+// Copyright (C) 2021-2024 CERN for the benefit of the Acts project
 //
 // This Source Code Form is subject to the terms of the Mozilla Public
 // License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -268,8 +268,7 @@ ActsExamples::ProcessCode ActsExamples::DigitizationAlgorithm::execute(
             // be added at the end.
             sourceLinks.insert(sourceLinks.end(), sourceLink);
 
-            measurements.emplace_back(
-                createMeasurement(dParameters, sourceLink));
+            createMeasurement(measurements, dParameters, sourceLink);
             clusters.emplace_back(std::move(dParameters.cluster));
             // this digitization does hit merging so there can be more than one
             // mapping entry for each digitized hit.

Examples/Algorithms/Digitization/src/MeasurementCreation.cpp

@@ -1,43 +1,42 @@
 // This file is part of the Acts project.
 //
-// Copyright (C) 2021 CERN for the benefit of the Acts project
+// Copyright (C) 2021-2024 CERN for the benefit of the Acts project
 //
 // This Source Code Form is subject to the terms of the Mozilla Public
 // License, v. 2.0. If a copy of the MPL was not distributed with this
 // file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 #include "ActsExamples/Digitization/MeasurementCreation.hpp"
 
+#include "Acts/EventData/MeasurementHelpers.hpp"
 #include "Acts/EventData/SourceLink.hpp"
 #include "ActsExamples/EventData/IndexSourceLink.hpp"
+#include "ActsExamples/EventData/Measurement.hpp"
 
 #include <stdexcept>
 #include <string>
 #include <utility>
 
-ActsExamples::Measurement ActsExamples::createMeasurement(
-    const DigitizedParameters& dParams, const IndexSourceLink& isl) {
+ActsExamples::VariableBoundMeasurementProxy ActsExamples::createMeasurement(
+    MeasurementContainer& container, const DigitizedParameters& dParams,
+    const IndexSourceLink& isl) {
   Acts::SourceLink sl{isl};
-  switch (dParams.indices.size()) {
-    case 1u: {
-      auto [indices, par, cov] = measurementConstituents<1>(dParams);
-      return ActsExamples::Measurement(std::move(sl), indices, par, cov);
-    }
-    case 2u: {
-      auto [indices, par, cov] = measurementConstituents<2>(dParams);
-      return ActsExamples::Measurement(std::move(sl), indices, par, cov);
-    };
-    case 3u: {
-      auto [indices, par, cov] = measurementConstituents<3>(dParams);
-      return ActsExamples::Measurement(std::move(sl), indices, par, cov);
-    };
-    case 4u: {
-      auto [indices, par, cov] = measurementConstituents<4>(dParams);
-      return ActsExamples::Measurement(std::move(sl), indices, par, cov);
-    };
-    default:
-      std::string errorMsg = "Invalid/mismatching measurement dimension: " +
-                             std::to_string(dParams.indices.size());
-      throw std::runtime_error(errorMsg.c_str());
+
+  if (dParams.indices.size() > 4u) {
+    std::string errorMsg = "Invalid/mismatching measurement dimension: " +
+                           std::to_string(dParams.indices.size());
+    throw std::runtime_error(errorMsg.c_str());
   }
+
+  return Acts::visit_measurement(
+      dParams.indices.size(), [&](auto dim) -> VariableBoundMeasurementProxy {
+        auto [indices, par, cov] = measurementConstituents<dim>(dParams);
+        FixedBoundMeasurementProxy<dim> measurement =
+            container.makeMeasurement<dim>();
+        measurement.setSourceLink(sl);
+        measurement.setSubspaceIndices(indices);
+        measurement.parameters() = par;
+        measurement.covariance() = cov;
+        return measurement;
+      });
 }

Examples/Algorithms/TrackFinding/src/HoughTransformSeeder.cpp

@@ -529,7 +529,8 @@ void ActsExamples::HoughTransformSeeder::addMeasurements(
         // are transformed to the bound space where we do know their location.
         // if the local parameters are not measured, this results in a
         // zero location, which is a reasonable default fall-back.
-        const auto& measurement = measurements[sourceLink.index()];
+        const ConstVariableBoundMeasurementProxy measurement =
+            measurements.getMeasurement(sourceLink.index());
 
         assert(measurement.contains(Acts::eBoundLoc0) &&
                "Measurement does not contain the required bound loc0");

Examples/Algorithms/TrackFinding/src/SpacePointMaker.cpp

@@ -126,7 +126,8 @@ ActsExamples::ProcessCode ActsExamples::SpacePointMaker::execute(
 
   spOpt.paramCovAccessor = [&measurements](Acts::SourceLink slink) {
     const auto islink = slink.get<IndexSourceLink>();
-    const auto& meas = measurements[islink.index()];
+    const ConstVariableBoundMeasurementProxy meas =
+        measurements.getMeasurement(islink.index());
 
     return std::make_pair(meas.fullParameters(), meas.fullCovariance());
   };

Examples/Algorithms/TrackFitting/src/TrackFittingAlgorithm.cpp

@@ -18,6 +18,7 @@
 #include "Acts/Surfaces/PerigeeSurface.hpp"
 #include "Acts/Surfaces/Surface.hpp"
 #include "Acts/Utilities/Result.hpp"
+#include "ActsExamples/EventData/Measurement.hpp"
 #include "ActsExamples/EventData/MeasurementCalibration.hpp"
 #include "ActsExamples/EventData/ProtoTrack.hpp"
 #include "ActsExamples/Framework/AlgorithmContext.hpp"
@@ -126,7 +127,8 @@ ActsExamples::ProcessCode ActsExamples::TrackFittingAlgorithm::execute(
 
     // Fill the source links via their indices from the container
     for (auto hitIndex : protoTrack) {
-      const auto& measurement = measurements.at(hitIndex);
+      ConstVariableBoundMeasurementProxy measurement =
+          measurements.getMeasurement(hitIndex);
       trackSourceLinks.push_back(measurement.sourceLink());
     }
 

Examples/Framework/CMakeLists.txt

@@ -5,6 +5,7 @@ set(ActsExamplesFramework_SOURCES)
 add_library(
     ActsExamplesFramework
     SHARED
+    src/EventData/Measurement.cpp
     src/EventData/MeasurementCalibration.cpp
     src/EventData/ScalingCalibrator.cpp
     src/Framework/IAlgorithm.cpp

Examples/Framework/ML/src/NeuralCalibrator.cpp

@@ -1,6 +1,6 @@
 // This file is part of the Acts project.
 //
-// Copyright (C) 2023 CERN for the benefit of the Acts project
+// Copyright (C) 2023-2024 CERN for the benefit of the Acts project
 //
 // This Source Code Form is subject to the terms of the Mozilla Public
 // License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -106,7 +106,8 @@ void ActsExamples::NeuralCalibrator::calibrate(
   const Acts::Surface& referenceSurface = trackState.referenceSurface();
   auto trackParameters = trackState.parameters();
 
-  const auto& measurement = measurements[idxSourceLink.index()];
+  const ConstVariableBoundMeasurementProxy measurement =
+      measurements.getMeasurement(idxSourceLink.index());
 
   assert(measurement.contains(Acts::eBoundLoc0) &&
          "Measurement does not contain the required bound loc0");
@@ -171,21 +172,24 @@ void ActsExamples::NeuralCalibrator::calibrate(
   std::size_t iLoc0 = m_nComponents + iMax * 2;
   std::size_t iVar0 = 3 * m_nComponents + iMax * 2;
 
-  Measurement measurementCopy = measurement;
-  measurementCopy.parameters()[boundLoc0] = output[iLoc0];
-  measurementCopy.parameters()[boundLoc1] = output[iLoc0 + 1];
-  measurementCopy.covariance()(boundLoc0, boundLoc0) = output[iVar0];
-  measurementCopy.covariance()(boundLoc1, boundLoc1) = output[iVar0 + 1];
-
   Acts::visit_measurement(measurement.size(), [&](auto N) -> void {
     constexpr std::size_t kMeasurementSize = decltype(N)::value;
+    const ConstFixedBoundMeasurementProxy<kMeasurementSize> fixedMeasurement =
+        measurement;
+
+    Acts::ActsVector<kMeasurementSize> calibratedParameters =
+        fixedMeasurement.parameters();
+    Acts::ActsSquareMatrix<kMeasurementSize> calibratedCovariance =
+        fixedMeasurement.covariance();
+
+    calibratedParameters[boundLoc0] = output[iLoc0];
+    calibratedParameters[boundLoc1] = output[iLoc0 + 1];
+    calibratedCovariance(boundLoc0, boundLoc0) = output[iVar0];
+    calibratedCovariance(boundLoc1, boundLoc1) = output[iVar0 + 1];
 
     trackState.allocateCalibrated(kMeasurementSize);
-    trackState.calibrated<kMeasurementSize>() =
-        measurementCopy.parameters<kMeasurementSize>();
-    trackState.calibratedCovariance<kMeasurementSize>() =
-        measurementCopy.covariance<kMeasurementSize>();
-    trackState.setSubspaceIndices(
-        measurementCopy.subspaceIndices<kMeasurementSize>());
+    trackState.calibrated<kMeasurementSize>() = calibratedParameters;
+    trackState.calibratedCovariance<kMeasurementSize>() = calibratedCovariance;
+    trackState.setSubspaceIndices(fixedMeasurement.subspaceIndices());
   });
 }