From b243b048ea2c2af0dd7fe862b2f7c49b690dc687 Mon Sep 17 00:00:00 2001
From: Carsten Burgard <carsten.burgard@gmail.com>
Date: Fri, 13 Jan 2023 15:49:56 +0100
Subject: [PATCH] added new constructor for RooExtendPdf

---
 roofit/roofitcore/inc/RooExtendPdf.h   |  4 +++-
 roofit/roofitcore/src/RooExtendPdf.cxx | 25 ++++++++++++++++++++++++-
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/roofit/roofitcore/inc/RooExtendPdf.h b/roofit/roofitcore/inc/RooExtendPdf.h
index 78afdb645fc03..bc21b69d6ce3f 100644
--- a/roofit/roofitcore/inc/RooExtendPdf.h
+++ b/roofit/roofitcore/inc/RooExtendPdf.h
@@ -24,7 +24,9 @@ class RooExtendPdf : public RooAbsPdf {
 
   RooExtendPdf() ;
   RooExtendPdf(const char *name, const char *title, RooAbsPdf& pdf,
-          RooAbsReal& norm, const char* rangeName=nullptr) ;
+	       RooAbsReal& norm, const char* rangeName=nullptr) ;
+  RooExtendPdf(const char *name, const char *title, RooAbsPdf& pdf,
+	       double norm, const char* rangeName=nullptr) ;  
   RooExtendPdf(const RooExtendPdf& other, const char* name=nullptr) ;
   TObject* clone(const char* newname) const override { return new RooExtendPdf(*this,newname) ; }
   ~RooExtendPdf() override ;
diff --git a/roofit/roofitcore/src/RooExtendPdf.cxx b/roofit/roofitcore/src/RooExtendPdf.cxx
index 62ec65898dd36..8ee1b8a20e1bb 100644
--- a/roofit/roofitcore/src/RooExtendPdf.cxx
+++ b/roofit/roofitcore/src/RooExtendPdf.cxx
@@ -69,7 +69,7 @@ RooExtendPdf::RooExtendPdf() : _rangeName(0)
 /// \param[in] rangeName  If given, the number of events denoted by `norm` is interpreted as
 /// the number of events in this range only
 RooExtendPdf::RooExtendPdf(const char *name, const char *title, RooAbsPdf& pdf,
-            RooAbsReal& norm, const char* rangeName) :
+			   RooAbsReal& norm, const char* rangeName) :
   RooAbsPdf(name,title),
   _pdf("pdf", "PDF", this, pdf),
   _n("n","Normalization",this,norm),
@@ -81,6 +81,29 @@ RooExtendPdf::RooExtendPdf(const char *name, const char *title, RooAbsPdf& pdf,
   setPlotLabel(_pdf->getPlotLabel()) ;
 }
 
+/// Constructor. The ExtendPdf behaves identical to the supplied input pdf,
+/// but adds an extended likelihood term. expectedEvents() will return
+/// `norm` if `rangeName` remains empty. If `rangeName` is not empty,
+/// `norm` will refer to this range, and expectedEvents will return the
+/// total number of events over the full range of the observables.
+/// \param[in] name   Name of the pdf
+/// \param[in] title  Title of the pdf (for plotting)
+/// \param[in] pdf    The pdf to be extended
+/// \param[in] norm   Expected number of events
+/// \param[in] rangeName  If given, the number of events denoted by `norm` is interpreted as
+/// the number of events in this range only
+RooExtendPdf::RooExtendPdf(const char *name, const char *title, RooAbsPdf& pdf,
+			   double norm, const char* rangeName) :
+  RooAbsPdf(name,title),
+  _pdf("pdf", "PDF", this, pdf),
+  _n("n","Normalization",this,*new RooRealVar(TString::Format("%s_norm",name),TString::Format("%s_norm",title),norm),true, false, true),
+  _rangeName(RooNameReg::ptr(rangeName))
+{
+   // Copy various setting from pdf
+  setUnit(_pdf->getUnit()) ;
+  setPlotLabel(_pdf->getPlotLabel()) ;
+}
+
 
 
 RooExtendPdf::RooExtendPdf(const RooExtendPdf& other, const char* name) :