DEventProcessor_p2pi_trees.cc

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// $Id$
//
//    File: DEventProcessor_p2pi_trees.cc
// Created: Wed Mar 29 16:34:58 EDT 2017
// Creator: elton (on Linux ifarm1401.jlab.org 3.10.0-327.el7.x86_64 x86_64)
//

#include "DEventProcessor_p2pi_trees.h"

// Routine used to create our DEventProcessor

extern "C"
{
   void InitPlugin(JApplication *locApplication)
   {
      InitJANAPlugin(locApplication);
      locApplication->AddProcessor(new DEventProcessor_p2pi_trees()); //register this plugin
      locApplication->AddFactoryGenerator(new DFactoryGenerator_p2pi_trees()); //register the factory generator
   }
} // "C"

//------------------
// init
//------------------
jerror_t DEventProcessor_p2pi_trees::init(void)
{
   // This is called once at program startup.

   /*
   //OPTIONAL: Create an EventStore skim.  
   string locSkimFileName = "p2pi_trees.idxa";
   dEventStoreSkimStream.open(locSkimFileName.c_str());
   dEventStoreSkimStream << "IDXA" << endl;
   */

   return NOERROR;
}

//------------------
// brun
//------------------
jerror_t DEventProcessor_p2pi_trees::brun(jana::JEventLoop* locEventLoop, int32_t locRunNumber)
{
   // This is called whenever the run number changes

   return NOERROR;
}

//------------------
// evnt
//------------------
jerror_t DEventProcessor_p2pi_trees::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->RootFillLock(this);
   //  ... fill historgrams or trees ...
   // japp->RootFillUnLock(this);

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

   /*********************************************************** REQUIRED ***********************************************************/

   //REQUIRED: To run an analysis, You MUST call one at least of the below code fragments. 
      //JANA is on-demand, so if you don't call one of these, then your analysis won't run. 

   
   //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, "p2pi_trees");
   

   
   //Optional: 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);


   return NOERROR;
}

int DEventProcessor_p2pi_trees::Get_FileNumber(JEventLoop* locEventLoop) const
{
   //Assume that the file name is in the format: *_X.ext, where:
      //X is the file number (a string of numbers of any length)
      //ext is the file extension (probably .evio or .hddm)

   //get the event source
   JEventSource* locEventSource = locEventLoop->GetJEvent().GetJEventSource();
   if(locEventSource == NULL)
      return -1;

   //get the source file name (strip the path)
   string locSourceFileName = locEventSource->GetSourceName();

   //find the last "_" & "." indices
   size_t locUnderscoreIndex = locSourceFileName.rfind("_");
   size_t locDotIndex = locSourceFileName.rfind(".");
   if((locUnderscoreIndex == string::npos) || (locDotIndex == string::npos))
      return -1;

   size_t locNumberLength = locDotIndex - locUnderscoreIndex - 1;
   string locFileNumberString = locSourceFileName.substr(locUnderscoreIndex + 1, locNumberLength);

   int locFileNumber = -1;
   istringstream locFileNumberStream(locFileNumberString);
   locFileNumberStream >> locFileNumber;

   return locFileNumber;
}

//------------------
// erun
//------------------
jerror_t DEventProcessor_p2pi_trees::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_p2pi_trees::fini(void)
{
   // Called before program exit after event processing is finished.
   if(dEventStoreSkimStream.is_open())
      dEventStoreSkimStream.close();
   return NOERROR;
}