Example of TMap and TClonesArray IO
//* Test of Root I/O with a simple map and connected array 6/18/98 RXD
//
// structure is: TMap containing integer key with a separate class as value.
// the value object contains a float and a pointer to an array of other objects
#include <stdlib.h>
#include "TROOT.h"
#include "TFile.h"
#include "TTree.h"
#include "TBranch.h"
#include "TMap.h"
#include "TClonesArray.h"
#include "TObject.h"
#include "KeyVal.h"
//______________________________________________________________________________
main() {
TROOT simple("simple","Example of creation of a tree");
Int_t comp = 1; // by default file is compressed
Int_t split = 0; // by default, split Event in sub branches
Int_t write = 1; // by default the tree is filled
Int_t testKey[] = {6,10,1,0};
Int_t testType[] = {1,7,9,23};
Float_t testE[] = {22.,1.,0.3,4.};
Int_t nVal = 4;
TFile *hfile;
TMap *testMap = 0;
TTree *tree;
// Fill event, header and tracks with some random numbers
Int_t nb = 0;
Int_t ev;
Int_t bufsize;
/// This file is now becoming the current directory.
hfile = new TFile("Event.root","RECREATE","TTree benchmark ROOT file");
hfile->SetCompressionLevel(comp);
// Create a ROOT Tree and one superbranch
tree = new TTree("T","An example of a ROOT tree");
tree->SetAutoSave(1000000000); // autosave when 1 Gbyte written
bufsize = 256000;
// create the map to be written out and an iterator for it
testMap = new TMap(17,0);
TMapIter next(testMap);
TClonesArray *testClone = new TClonesArray("McPart");
TClonesArray &mcpart = *testClone;
tree->Branch("testMap", "TMap", &testMap, bufsize,split);
tree->Branch("testClone", "TClonesArray", &testClone, bufsize,split);
for (Int_t i=0; i<nVal; ++i) {
new(mcpart[i]) McPart(testType[i]);
testMap->Add(new aKey(testKey[i]),new aVal(testE[i],
(McPart*)mcpart[i]));
printf("Particle type %i n",((McPart*)mcpart[i])->GetType());
}
if (write) {
nb += tree->Fill(); //fill the tree
printf(" tree filled with %i bytes n",nb);
hfile->Write();
tree->Print();
}
hfile->Close();
return 0;
}
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