From 5d3f77752e4a71397304680f055aee6a88a8aaeb Mon Sep 17 00:00:00 2001
From: Ray Culbertson <rlc@fnal.gov>
Date: Tue, 12 Mar 2024 12:06:40 -0500
Subject: [PATCH] implement TFileService access

---
 Mu2eUtilities/inc/compressPdgId.hh |  7 +++++--
 Mu2eUtilities/src/compressPdgId.cc | 10 +++++-----
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/Mu2eUtilities/inc/compressPdgId.hh b/Mu2eUtilities/inc/compressPdgId.hh
index 3737d50a02..48b505f157 100644
--- a/Mu2eUtilities/inc/compressPdgId.hh
+++ b/Mu2eUtilities/inc/compressPdgId.hh
@@ -3,6 +3,8 @@
 
 #include "Offline/DataProducts/inc/PDGCode.hh"
 #include "Offline/DataProducts/inc/CompressedPDGCode.hh"
+#include "art/Framework/Services/Registry/ServiceHandle.h"
+#include "art_root_io/TFileService.h"
 #include "TH1D.h"
 #include <string>
 
@@ -13,8 +15,9 @@ namespace mu2e {
   CompressedPDGCode::enum_type compressPDGCode(PDGCode::enum_type pdgId);
 
   // a histogram with text labels, ready for use with CompressedPDGCode
-  TH1D compressPDGCodeHisto(std::string name="compPdgId",
-                            std::string title="Compressed PDG ID");
+  TH1D* compressPDGCodeHisto(art::ServiceHandle<art::TFileService>& tfs,
+                             std::string name="compPdgId",
+                             std::string title="Compressed PDG ID");
 
   // compress PDG e,mu,gamma, pions and kaons produced
   // in cosmic generators into a index 0-7
diff --git a/Mu2eUtilities/src/compressPdgId.cc b/Mu2eUtilities/src/compressPdgId.cc
index 6bc78bc3ed..85748054b6 100644
--- a/Mu2eUtilities/src/compressPdgId.cc
+++ b/Mu2eUtilities/src/compressPdgId.cc
@@ -74,24 +74,24 @@ namespace mu2e {
     return code;
   }
 
-  TH1D compressPDGCodeHisto(std::string name, std::string title) {
+  TH1D* compressPDGCodeHisto(art::ServiceHandle<art::TFileService>& tfs,
+                             std::string name, std::string title) {
 
     float low = float(CompressedPDGCode::minBin) - 0.5;
     float hgh = float(CompressedPDGCode::maxBin) + 0.5;
     int nbin = CompressedPDGCode::maxBin - CompressedPDGCode::minBin +1;
 
-    TH1D hh(name.c_str(),title.c_str(),nbin,low,hgh);
+    auto hp = tfs->make<TH1D>(name.c_str(),title.c_str(),nbin,low,hgh);
 
     int rootBin = 0;
     for(int ibin=CompressedPDGCode::minBin;
         ibin<=CompressedPDGCode::maxBin; ibin++) {
       rootBin++;
       std::string name = CompressedPDGCode(ibin,false).name();
-      std::cout << rootBin << " " << name << "\n";
-      hh.GetXaxis()->SetBinLabel(rootBin,name.c_str());
+      hp->GetXaxis()->SetBinLabel(rootBin,name.c_str());
     }
 
-    return hh;
+    return hp;
   }