lcio/examples/cpp/rootDict

diff -N writeNTuple.C
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ writeNTuple.C	1 Dec 2010 09:45:49 -0000	1.1
@@ -0,0 +1,122 @@

+#ifndef __CINT__ 
+#include "IO/LCReader.h"
+#include "IOIMPL/LCFactory.h"
+#include "IMPL/LCCollectionVec.h"
+#include "IMPL/MCParticleImpl.h"
+#include "EVENT/MCParticle.h"
+#include "EVENT/LCEvent.h"
+#include "UTIL/LCTOOLS.h"
+#include <vector>
+#endif
+
+
+/** Example script for using the LCIO root dictionary.
+ *  writeNTuple: 
+ *  reads *.slcio file and creates a simple NTuple from the MCParticle collection.
+ *
+ */
+ 
+void writeNTuple(const char* FILEN) {
+  
+
+  std::string rootFileBaseName( FILEN , (strlen(FILEN) ) - strlen(".slcio") ) ;
+  std::string rootFileName = rootFileBaseName + std::string(".root") ;
+
+  //  std::cout << " rootFileBaseName: " << rootFileBaseName << std::endl ;
+
+  std::string mcpName("MCParticle") ;
+
+  const char* tupleNames = "px:py:pz:vx:vy:vz:ex:ey:ez:pdg:np:nd:gs:ss" ;
+  double px,py,pz,vx,vy,vz,ex,ey,ez ;
+  int pdg,np,nd,gs,ss ;
+
+
+  //just in case this script is executed multiple times
+  delete gROOT->GetListOfFiles()->FindObject( FILEN );
+  delete gROOT->GetListOfCanvases()->FindObject("c1");
+  
+  if (!TClassTable::GetDict("IMPL::ReconstructedParticleImpl")) {
+    unsigned res ;
+    
+    res = gSystem->Load("${LCIO}/lib/liblcio.so"); 
+    res = gSystem->Load("${LCIO}/lib/liblcioDict.so"); 
+  }
+  
+  
+  //--- create a ROOT file and an NTuple
+
+  TFile* file = new TFile( rootFileName.c_str()  , "RECREATE");    
+
+  TNtupleD *tuple= new TNtupleD("MCP", "", tupleNames );
+
+  std::cout << " loaded LCIO library and dictionary ... " << std::endl ;
+  
+  int nEvents = 0  ;
+  int maxEvt = 10000 ;  // change as needed
+
+  IO::LCReader* lcReader = IOIMPL::LCFactory::getInstance()->createLCReader() ;
+
+  lcReader->open( FILEN ) ;
+  
+
+  IMPL::LCCollectionVec emptyCol ;
+  
+  //----------- the event loop -----------
+  while( (evt = lcReader->readNextEvent()) != 0  && nEvents < maxEvt ) {
+    
+    //    UTIL::LCTOOLS::dumpEvent( evt ) ;
+    nEvents ++ ;
+
+    // ------- fill the MCParticle collection to tuple
+
+    IMPL::LCCollectionVec* col = (IMPL::LCCollectionVec*) evt->getCollection( mcpName  ) ;
+
+    int nMCP = col->getNumberOfElements() ;
+
+    for(int i=0 ; i<nMCP ; ++i){
+
+      EVENT::MCParticle* mcp =  (EVENT::MCParticle*) col->getElementAt(i) ;
+      
+      px = mcp->getMomentum()[0] ;
+      py = mcp->getMomentum()[1] ;
+      pz = mcp->getMomentum()[2] ;
+
+      ex = mcp->getEndpoint()[0] ;
+      ey = mcp->getEndpoint()[1] ;
+      ez = mcp->getEndpoint()[2] ;
+
+      vx = mcp->getVertex()[0] ;
+      vy = mcp->getVertex()[1] ;
+      vz = mcp->getVertex()[2] ;
+
+      pdg = mcp->getPDG() ;
+      np = mcp->getParents().size() ;
+      nd = mcp->getDaughters().size() ;
+      gs = mcp->getGeneratorStatus() ;
+      ss = mcp->getSimulatorStatus() ;
+
+      tuple->Fill(px,py,pz,vx,vy,vz,ex,ey,ez,pdg,np,nd,gs,ss) ;
+
+    }
+
+
+
+  }
+  // -------- end of event loop -----------
+
+  file->Write() ;
+  file->Close() ;
+  
+  delete file ;
+
+
+  std::cout << std::endl 
+	    <<  "  " <<  nEvents 
+	    << " events read from file: " 
+	    << FILEN << std::endl  ;
+  
+  
+  lcReader->close() ;
+  
+  delete lcReader ;
+}