PWGHF: Add a skeleton for HF + track task (#5345)

* Attempt to run a HF+track reconstruction

* Update taskBPlus.cxx

* Update taskBPlus.cxx

* Fix Clang

* Update taskBPlus.cxx

Author: ginnocen

Analysis/Tasks/PWGHF/CMakeLists.txt

@@ -72,3 +72,8 @@ o2_add_dpl_workflow(hf-task-jpsi
                     SOURCES taskJpsi.cxx
                     PUBLIC_LINK_LIBRARIES O2::Framework O2::AnalysisDataModel O2::AnalysisCore O2::DetectorsVertexing
                     COMPONENT_NAME Analysis)
+
+o2_add_dpl_workflow(hf-task-bplus
+                    SOURCES taskBPlus.cxx
+                    PUBLIC_LINK_LIBRARIES O2::Framework O2::AnalysisDataModel O2::AnalysisCore O2::DetectorsVertexing
+                    COMPONENT_NAME Analysis)

Analysis/Tasks/PWGHF/taskBPlus.cxx

@@ -0,0 +1,82 @@
+// Copyright CERN and copyright holders of ALICE O2. This software is
+// distributed under the terms of the GNU General Public License v3 (GPL
+// Version 3), copied verbatim in the file "COPYING".
+//
+// See http://alice-o2.web.cern.ch/license for full licensing information.
+//
+// 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.
+
+/// \file taskBplus.cxx
+/// \brief B+ analysis task
+///
+/// \author Gian Michele Innocenti <gian.michele.innocenti@cern.ch>, CERN
+/// \author Vít Kučera <vit.kucera@cern.ch>, CERN
+/// \author Nima Zardoshti <nima.zardoshti@cern.ch>, CERN
+
+#include "Framework/AnalysisTask.h"
+#include "Framework/HistogramRegistry.h"
+#include "AnalysisDataModel/HFSecondaryVertex.h"
+#include "AnalysisDataModel/HFCandidateSelectionTables.h"
+
+using namespace o2;
+using namespace o2::framework;
+using namespace o2::aod::hf_cand_prong2;
+using namespace o2::framework::expressions;
+
+void customize(std::vector<o2::framework::ConfigParamSpec>& workflowOptions)
+{
+  ConfigParamSpec optionDoMC{"doMC", VariantType::Bool, false, {"Fill MC histograms."}};
+  workflowOptions.push_back(optionDoMC);
+}
+
+#include "Framework/runDataProcessing.h"
+
+/// B+ analysis task
+struct TaskBplus {
+  HistogramRegistry registry{
+    "registry",
+    {{"hmassD0", "2-prong candidates;inv. mass (#pi K) (GeV/#it{c}^{2});entries", {HistType::kTH1F, {{500, 0., 5.}}}},
+     {"hptcand", "B+ candidates;candidate #it{p}_{T} (GeV/#it{c});entries", {HistType::kTH1F, {{100, 0., 10.}}}}}};
+
+  Configurable<int> d_selectionFlagD0{"d_selectionFlagD0", 1, "Selection Flag for D0"};
+  Configurable<int> d_selectionFlagD0bar{"d_selectionFlagD0bar", 1, "Selection Flag for D0bar"};
+  Configurable<double> cutEtaCandMax{"cutEtaCandMax", -1., "max. cand. pseudorapidity"};
+
+  Filter filterSelectCandidates = (aod::hf_selcandidate_d0::isSelD0 >= d_selectionFlagD0 || aod::hf_selcandidate_d0::isSelD0bar >= d_selectionFlagD0bar);
+
+  void process(aod::Collisions const& collisions, aod::BigTracks const& tracks, soa::Filtered<soa::Join<aod::HfCandProng2, aod::HFSelD0Candidate>> const& candidates)
+  {
+    for (auto& candidate : candidates) {
+      if (!(candidate.hfflag() & 1 << D0ToPiK)) {
+        continue;
+      }
+      if (cutEtaCandMax >= 0. && std::abs(candidate.eta()) > cutEtaCandMax) {
+        //Printf("Candidate: eta rejection: %g", candidate.eta());
+        continue;
+      }
+      if (candidate.isSelD0bar() >= d_selectionFlagD0bar) {
+        //Printf("Track size: %d", tracks.size());
+        registry.fill(HIST("hmassD0"), InvMassD0bar(candidate));
+        for (auto trackPos1 = tracks.begin(); trackPos1 != tracks.end(); ++trackPos1) {
+          if (trackPos1.signed1Pt() < 0) {
+            continue;
+          }
+          if (candidate.index0().collisionId() != trackPos1.collisionId()) {
+            continue;
+          }
+          //Printf("Positive track pt: %f", trackPos1.pt());
+          registry.fill(HIST("hptcand"), candidate.pt() + trackPos1.pt());
+        }
+      }
+    }
+  }
+};
+
+WorkflowSpec defineDataProcessing(ConfigContext const& cfgc)
+{
+  WorkflowSpec workflow{
+    adaptAnalysisTask<TaskBplus>("hf-task-bplus")};
+  return workflow;
+}