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Difficulty with Conditionals

whitebeard (14)
Hey!
I'm having a little difficulty with my code. Here it is:

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bool user::Execute(SampleFormat& sample, const EventFormat& event)
{
  // ***************************************************************************
  // Example of analysis with generated particles
  // Concerned samples : LHE/STDHEP/HEPMC
  // ***************************************************************************

  if (event.mc()!=0)
  {
    cout << "---------------NEW EVENT-------------------" << endl;

    // Initial state
   
      unsigned int n = event.mc()->particles().size();
      
      for (unsigned int i=0;i<n;i++)
      {
      const MCParticleFormat* prt = &event.mc()->particles()[i]; 

      if ( ((prt->pdgid()==13) && (prt->pdgid()==-13)) || ((prt->pdgid()==11) && (prt->pdgid()==-11) )
      {
      cout << "----------------------------------" << endl;
      cout << "MC particle" << endl;
      cout << "----------------------------------" << endl;

      // display index particle
      cout << "index=" << i+1;

      // display kinematics information
      cout << "px=" << prt->px()
                << " py=" << prt->py()
                << " pz=" << prt->pz()
                << " e="  << prt->e()
                << " m="  << prt->m()<< endl;
      cout << "pt=" << prt->pt() 
                << " eta=" << prt->eta() 
                << " phi=" << prt->phi() << endl;

    // Transverse missing energy (MET)
    cout << "MET pt=" << event.mc()->MET().pt()
         << " phi=" << event.mc()->MET().phi() << endl;
    cout << endl;

    // Transverse missing hadronic energy (MHT)
    cout << "MHT pt=" << event.mc()->MHT().pt()
              << " phi=" << event.mc()->MHT().phi() << endl;
    cout << endl;

    // Total transverse energy (TET)
    cout << "TET=" << event.mc()->TET() << endl;
    cout << endl;

    // Total transverse hadronic energy (THT)
    cout << "THT=" << event.mc()->THT() << endl; 
    cout << endl;
       
      Histm->Fill(prt->m());
      Histpt->Fill(prt->pt());
      Histpx->Fill(prt->px());
      Histpy->Fill(prt->py());
      Histpz->Fill(prt->pz());
      Histe->Fill(prt->e());
      Histeta->Fill(prt->eta());
      Histphi->Fill(prt->phi());
      }
    }
  }
 return true;
}


But it gives no information about the particles with the pdgid mentioned above. I have 50k events and there are two types of event: one with two particles -13 and 13 and the other with the particles 11 and -11.

Instead if I do:
if ( (prt->pdgid()==13) || (prt->pdgid()==-13) || (prt->pdgid()==11) || (prt->pdgid()==-11) )

It does read the information (related only to the particle 13 I guess?).

Can anyone help?
Last edited on
PanGalactic (1658)
You seem to have a fundamental misunderstanding of Boolean logic. The expression

 
 
 (prt->pdgid()==13) && (prt->pdgid()==-13))

is always false. There is no way for an immutable expression to evaluate to two different values. And if prt->pdgid() is a mutating function, we have some C++ language fundamentals to go over.
whitebeard (14)
Thank you for your reply, I got that cleared out. I have one more question:

If you do more than one if in the bool type of function, like:
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for (....)
{

 if (condition1) 
 {
 
 }

 if (condition2)
 {

 }

(...) 

 if (conditionN)
 {

 }
}


Does it read if(condition2) even if if(condition1) is true?


Last edited on
shadowmouse (539)
yes it does unless you use the else keyword.
whitebeard (14)
Thank you.
whitebeard (14)
Now I don't have an error in the code but it just doesn't fill the histogram I want to build.

Here's what I have:

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bool user::Execute(SampleFormat& sample, const EventFormat& event)
{
  // ***************************************************************************
  // Example of analysis with generated particles
  // Concerned samples : LHE/STDHEP/HEPMC
  // ***************************************************************************
  
  if (event.mc()!=0)
  {
    cout << "---------------NEW EVENT-------------------" << endl;

    // Initial state
    unsigned int n = event.mc()->particles().size();
      
      for (unsigned int i=0;i<n;i++)
      {
      const MCParticleFormat* prt = &event.mc()->particles()[i];

      if ( (prt->pdgid()== 13) )
      {
      cout << "----------------------------------" << endl;
      cout << "MC particle" << endl;
      cout << "----------------------------------" << endl;

      // display index particle
      cout << "index=" << i+1;

      // display kinematics information
      cout << "px=" << prt->px()
                << " py=" << prt->py()
                << " pz=" << prt->pz()
                << " e="  << prt->e()
                << " m="  << prt->m()<< endl;
      cout << "pt=" << prt->pt() 
                << " eta=" << prt->eta() 
                << " phi=" << prt->phi() << endl;
      
/*      // display particle mother id
      if (part.mother1()==0) 
      {
        cout << "particle with no mother." << endl;
      }
      else if (part.mother2()==0 || part.mother1()==part.mother2())
      {
        const MCParticleFormat* mother = part.mother1();
        cout << "particle coming from the decay of " 
             << mother->pdgid() << "." << endl;
      }
      else
      {
        const MCParticleFormat* mother1 = part.mother1();
        const MCParticleFormat* mother2 = part.mother2();
        cout << "particle coming from interaction between "
             << mother1->pdgid() << " and " << mother2->pdgid()
             << "." << endl;
      }
*/    

    // Transverse missing energy (MET)
    cout << "MET pt=" << event.mc()->MET().pt()
         << " phi=" << event.mc()->MET().phi() << endl;
    cout << endl;

    // Transverse missing hadronic energy (MHT)
    cout << "MHT pt=" << event.mc()->MHT().pt()
              << " phi=" << event.mc()->MHT().phi() << endl;
    cout << endl;

    // Total transverse energy (TET)
    cout << "TET=" << event.mc()->TET() << endl;
    cout << endl;

    // Total transverse hadronic energy (THT)
    cout << "THT=" << event.mc()->THT() << endl; 
   cout << endl;


       if ( prt->mother2()==0 || prt->mother1()==prt->mother2() )
       {
       const MCParticleFormat* mother = prt->mother1();
       
       if ( mother->pdgid() == 24 ) { Histpt->Fill(prt->pt()); }
       }
   }
  }
 }

  return true;
}


When I open my file.root I don't have any entries and it must be related to the following code I wrote:

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if ( prt->mother2()==0 || prt->mother1()==prt->mother2() )
       {
       const MCParticleFormat* mother = prt->mother1();
       
       if ( mother->pdgid() == 24 ) { Histpt->Fill(prt->pt()); }
       }


Can anyone help?

Last edited on
whitebeard (14)
Problem solved!
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