Problem 2541

Created attachment 811 [details]
Minimum working example included above as a .cc file

When using the G4AnalysisManager::CreateH1("name", "title", std::vector<G4double> edges) Constructor, the histogram is not created and the warning 'Illegal value of x (min >= max)' is given. Same goes for H2 and H3. A minimum working example showcasing this bug is given at the end. The problem is in geant4-v11.1.1/source/analysis/management/include/G4HnInformation.hh, where in lines 56-61, the fMinValue and fMaxValue of G4HnDimension are both set to zero; afterwards in geant4-v11.1.1/source/analysis/management/src/G4HnInformation.cc, in lines 174-178, these zeroes are compared to each other and the check obviously fails. This problem would not occur, if the CheckMinMax(G4double, G4double)-function in G4HnInformation.cc, line 137-147 were to be used, but this would in turn eliminate the information about which dimension's values are off.

MWE:
#include "G4RunManagerFactory.hh"
#include "G4UImanager.hh"
#include "FTFP_BERT.hh"
#include "G4AnalysisManager.hh"

#include "G4VUserDetectorConstruction.hh"
#include "G4VUserActionInitialization.hh"

#include "G4VPhysicalVolume.hh"

#include <vector>

class DetectorConstruction : public G4VUserDetectorConstruction
{
public:
  DetectorConstruction() {}
  ~DetectorConstruction() override {}

  G4VPhysicalVolume *Construct() override { return nullptr; };
};

class ActionInitialization : public G4VUserActionInitialization
{
public:
  ActionInitialization() {}
  ~ActionInitialization() override {}

  void Build() const override {}
};

int main(int argc, char **argv)
{
  auto *runManager =
      G4RunManagerFactory::CreateRunManager(G4RunManagerType::Default);

  auto *analysisManager = G4AnalysisManager::Instance();
  std::vector<G4double> edges = {1., 2., 3., 4.};
  int id = analysisManager->CreateH1("name", "title", edges);
  if (id == G4Analysis::kInvalidId)
  {
    //this prints, in addition to a G4 warning message
    G4cout << "ID is invalid" << G4endl;
  }
  // Set mandatory initialization classes
  //
  // Detector construction
  runManager->SetUserInitialization(new DetectorConstruction());

  // Physics list
  runManager->SetUserInitialization(new FTFP_BERT);

  // User action initialization
  runManager->SetUserInitialization(new ActionInitialization());
  runManager->BeamOn(1);

  delete runManager;
}