TMVAClassifierApplication

Based on $ROOTSYS/tutorials/tmva/TMVAClassificationApplication.C

Run with: chanser_mva RunSignalIDResult.C

Note this is ROOT scripting for python version see RunSignalIDResult.ipynb

auto input = GetClassificationFile();

auto *signalTree     = dynamic_cast<TTree*>(input->Get("TreeS"));


//Example 1
//If I know the tree only contains floats
//Full path to training directory
ResultByFloatTree classif("/work/dump/tmva/TMVAClassificationTut","MLP",signalTree);

 Long64_t Nent=signalTree->GetEntries();
 for(Int_t i=0;i<Nent;i++){
   signalTree->GetEntry(i);
   classif.Eval();//get the MVA uput value for this event
 }
 /////////////////////////////////////////////////////////
 //Example 2
 //if the tree contains other than floats I will convert
 //and add the response to the internal tree.
 //To make a copy of the tree and save t file last arg =>kTRUE
 ResultByTree classif2("/work/dump/tmva/TMVAClassificationTut","MLP",signalTree,kFALSE);
 classif2.AddToTree(); //this works for ResultsByFLoatTree too

 //now can look in MLP.root for tree + response
 signalTree->Draw("var1:MLP");

 ////////////////////////////////////////////////////////
 ///Example 3 using nameToFloatRef_t
 Float_t v1,v2,v3,v4,val;
 signalTree->SetBranchAddress( "var1", &v1 );
 signalTree->SetBranchAddress( "var2", &v2 );
 signalTree->SetBranchAddress( "var3", &v3 );
 signalTree->SetBranchAddress( "var4", &v4 );
 nameToFloatRef_t links;
 links["var1"]=&v1; //these do not have to be variables linked to a tree
 links["var2"]=&v2; //they can be a reference to any Float_t
 links["var3"]=&v3; //these do not have to be variables linked to a tree
 links["var4"]=&v4; //they can be a reference to any Float_t
 ResultByRefLink clasif3("/work/dump/tmva/TMVAClassificationTut","MLP",links);
 TH1F his3("MLP","MLP using reference link",100,0,1);
 for(Int_t i=0;i<Nent;i++){
   signalTree->GetEntry(i);
   his3.Fill(clasif3.Eval());
 }

his3.DrawCopy();