Core/EventData/MultiComponentBoundTrackParametersTests.cpp

0001 // This file is part of the Acts project.
0002 //
0003 // Copyright (C) 2017-2020 CERN for the benefit of the Acts project
0004 //
0005 // This Source Code Form is subject to the terms of the Mozilla Public
0006 // License, v. 2.0. If a copy of the MPL was not distributed with this
0007 // file, You can obtain one at http://mozilla.org/MPL/2.0/.
0008
0009 #include <boost/test/unit_test.hpp>
0010
0011 #include "Acts/Definitions/Algebra.hpp"
0012 #include "Acts/Definitions/TrackParametrization.hpp"
0013 #include "Acts/Definitions/Units.hpp"
0014 #include "Acts/EventData/GenericBoundTrackParameters.hpp"
0015 #include "Acts/EventData/ParticleHypothesis.hpp"
0016 #include "Acts/Geometry/GeometryContext.hpp"
0017 #include "Acts/Surfaces/Surface.hpp"
0018 #include <Acts/EventData/Charge.hpp>
0019 #include <Acts/EventData/MultiComponentTrackParameters.hpp>
0020 #include <Acts/Surfaces/PlaneSurface.hpp>
0021
0022 #include <algorithm>
0023 #include <initializer_list>
0024 #include <memory>
0025 #include <optional>
0026 #include <tuple>
0027 #include <vector>
0028
0029 using namespace Acts;
0030
0031 static const auto particleHypothesis = ParticleHypothesis::pion();
0032
0033 BOOST_AUTO_TEST_CASE(test_constructors) {
0034   std::vector<std::tuple<double, BoundVector, BoundSquareMatrix>> a;
0035   a.push_back({1.0, BoundVector::Ones(), BoundSquareMatrix::Identity()});
0036
0037   std::vector<std::tuple<double, BoundVector, std::optional<BoundSquareMatrix>>>
0038       b;
0039   b.push_back({1.0, BoundVector::Ones(), BoundSquareMatrix::Identity()});
0040
0041   auto surface = Acts::Surface::makeShared<Acts::PlaneSurface>(
0042       Vector3::Ones(), Vector3::Ones().normalized());
0043
0044   const auto ap =
0045       MultiComponentBoundTrackParameters(surface, a, particleHypothesis);
0046   const auto bp =
0047       MultiComponentBoundTrackParameters(surface, b, particleHypothesis);
0048   const auto aps = MultiComponentBoundTrackParameters(
0049       surface, std::get<1>(a.front()), std::get<2>(a.front()),
0050       particleHypothesis);
0051   const auto bps = MultiComponentBoundTrackParameters(
0052       surface, std::get<1>(b.front()), std::get<2>(b.front()),
0053       particleHypothesis);
0054
0055   BOOST_CHECK(b == ap.components());
0056   BOOST_CHECK(ap.components() == bp.components());
0057   BOOST_CHECK(bp.components() == aps.components());
0058   BOOST_CHECK(aps.components() == bps.components());
0059 }
0060
0061 BOOST_AUTO_TEST_CASE(test_accessors) {
0062   using cov_t = std::optional<BoundSquareMatrix>;
0063   for (const auto &cov : {cov_t{}, cov_t{BoundSquareMatrix::Identity()},
0064                           cov_t{BoundSquareMatrix::Identity()}}) {
0065     auto surface = Acts::Surface::makeShared<Acts::PlaneSurface>(
0066         Vector3::Ones(), Vector3::Ones().normalized());
0067
0068     const BoundTrackParameters single_pars(surface, BoundVector::Ones(), cov,
0069                                            particleHypothesis);
0070
0071     const auto multi_pars = [&]() {
0072       std::vector<
0073           std::tuple<double, BoundVector, std::optional<BoundSquareMatrix>>>
0074           a;
0075       for (int i = 0; i < 4; ++i) {
0076         a.push_back({0.25, single_pars.parameters(), single_pars.covariance()});
0077       }
0078       return MultiComponentBoundTrackParameters(surface, a, particleHypothesis);
0079     }();
0080
0081     BOOST_CHECK_EQUAL(multi_pars.absoluteMomentum(),
0082                       single_pars.absoluteMomentum());
0083     BOOST_CHECK_EQUAL(multi_pars.charge(), single_pars.charge());
0084     BOOST_CHECK_EQUAL(multi_pars.fourPosition(GeometryContext{}),
0085                       single_pars.fourPosition(GeometryContext{}));
0086     BOOST_CHECK_EQUAL(multi_pars.momentum(), single_pars.momentum());
0087     BOOST_CHECK_EQUAL(multi_pars.parameters(), single_pars.parameters());
0088     BOOST_CHECK_EQUAL(multi_pars.position(GeometryContext{}),
0089                       single_pars.position(GeometryContext{}));
0090     BOOST_CHECK_EQUAL(multi_pars.transverseMomentum(),
0091                       single_pars.transverseMomentum());
0092     BOOST_CHECK_EQUAL(multi_pars.direction(), single_pars.direction());
0093
0094     // Check the behaviour for std::nullopt or zero covariance
0095     if (cov && *cov != BoundSquareMatrix::Zero()) {
0096       BOOST_CHECK_EQUAL(*multi_pars.covariance(), *single_pars.covariance());
0097     } else {
0098       BOOST_CHECK(!multi_pars.covariance());
0099     }
0100   }
0101 }