DEventProcessor_ppi0gamma_hists.cc

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// $Id$
//
//    File: DEventProcessor_ppi0gamma_hists.cc
// Created: Wed Mar 11 20:34:22 EDT 2015
// Creator: jrsteven (on Linux halldw1.jlab.org 2.6.32-504.8.1.el6.x86_64 x86_64)
//

#include "DEventProcessor_ppi0gamma_hists.h"

// Routine used to create our DEventProcessor

extern "C"
{
   void InitPlugin(JApplication *locApplication)
   {
      InitJANAPlugin(locApplication);
      locApplication->AddProcessor(new DEventProcessor_ppi0gamma_hists()); //register this plugin
      locApplication->AddFactoryGenerator(new DFactoryGenerator_ppi0gamma_hists()); //register the factory generator
   }
} // "C"

//------------------
// init
//------------------
jerror_t DEventProcessor_ppi0gamma_hists::init(void)
{
   // This is called once at program startup. If you are creating
   // and filling historgrams in this plugin, you should lock the
   // ROOT mutex like this:
   //
   // japp->RootWriteLock();
   //  ... create historgrams or trees ...
   // japp->RootUnLock();
   //

   return NOERROR;
}

//------------------
// brun
//------------------
jerror_t DEventProcessor_ppi0gamma_hists::brun(jana::JEventLoop* locEventLoop, int locRunNumber)
{
   // This is called whenever the run number changes

   return NOERROR;
}

//------------------
// evnt
//------------------
jerror_t DEventProcessor_ppi0gamma_hists::evnt(jana::JEventLoop* locEventLoop, uint64_t locEventNumber)
{
   // This is called for every event. Use of common resources like writing
   // to a file or filling a histogram should be mutex protected. Using
   // locEventLoop->Get(...) to get reconstructed objects (and thereby activating the
   // reconstruction algorithm) should be done outside of any mutex lock
   // since multiple threads may call this method at the same time.
   //
   // Here's an example:
   //
   // vector<const MyDataClass*> mydataclasses;
   // locEventLoop->Get(mydataclasses);
   //
   // japp->RootWriteLock();
   //  ... fill historgrams or trees ...
   // japp->RootUnLock();

   // DOCUMENTATION:
   // ANALYSIS library: https://halldweb1.jlab.org/wiki/index.php/GlueX_Analysis_Software

   // Get the analysis results for all DReactions. 
      //Getting these objects triggers the analysis, if it wasn't performed already. 
      //These objects contain the DParticleCombo objects that survived the DAnalysisAction cuts that were added to the DReactions
   vector<const DAnalysisResults*> locAnalysisResultsVector;
   locEventLoop->Get(locAnalysisResultsVector);

   //Recommended: Write surviving particle combinations (if any) to output ROOT TTree
      //If no cuts are performed by the analysis actions added to a DReaction, then this saves all of its particle combinations. 
      //The event writer gets the DAnalysisResults objects from JANA, performing the analysis. 
   // string is DReaction factory tag: will fill trees for all DReactions that are defined in the specified factory
   const DEventWriterROOT* locEventWriterROOT = NULL;
   locEventLoop->GetSingle(locEventWriterROOT);
   //locEventWriterROOT->Fill_DataTrees(locEventLoop, "ppi0gamma_hists");

   return NOERROR;
}

//------------------
// erun
//------------------
jerror_t DEventProcessor_ppi0gamma_hists::erun(void)
{
   // This is called whenever the run number changes, before it is
   // changed to give you a chance to clean up before processing
   // events from the next run number.
   return NOERROR;
}

//------------------
// fini
//------------------
jerror_t DEventProcessor_ppi0gamma_hists::fini(void)
{
   // Called before program exit after event processing is finished.
   return NOERROR;
}