rf508_listsetmanip.C

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/// \file
/// \ingroup tutorial_roofit
/// \notebook -nodraw
///  'ORGANIZATION AND SIMULTANEOUS FITS' RooFit tutorial macro #508
///
///    RooArgSet and RooArgList tools and tricks
///
/// \macro_output
/// \macro_code
/// \author 07/2008 - Wouter Verkerke 


#include "RooRealVar.h"
#include "RooDataSet.h"
#include "RooGaussian.h"
#include "RooConstVar.h"
#include "TCanvas.h"
#include "TAxis.h"
#include "RooPlot.h"
#include "RooArgSet.h"
#include "RooArgList.h"
#include "RooCategory.h"
using namespace RooFit ;


void rf508_listsetmanip()
{

   // C r e a t e   d u m m y   o b j e c t s 
   // ---------------------------------------

   // Create some variables
   RooRealVar a("a","a",1,-10,10) ;
   RooRealVar b("b","b",2,-10,10) ;
   RooRealVar c("c","c",3,-10,10) ;
   RooRealVar d("d","d",4,-10,10) ;
   RooRealVar x("x","x",0,-10,10) ;
   c.setError(0.5) ;
   a.setConstant() ;
   b.setConstant() ;

   // Create a category
   RooCategory e("e","e") ;
   e.defineType("sig") ;
   e.defineType("bkg") ;

   // Create a pdf
   RooGaussian g("g","g",x,a,b) ;



   // C r e a t i n g ,   f i l l i n g   R o o A r g S e t s 
   // -------------------------------------------------------

   // A RooArgSet is a set of RooAbsArg objects. Each object in the set must have
   // a unique name 

   // Set constructors exists with up to 9 initial arguments
   RooArgSet s(a,b) ;

   // At any time objects can be added with add()
   s.add(e) ;

   // Add up to 9 additional arguments in one call
   s.add(RooArgSet(c,d)) ;

   // Sets can contain any type of RooAbsArg, also pdf and functions
   s.add(g) ;

   // Remove element d
   s.remove(d) ;



   // A c c e s s i n g   R o o A r g S e t   c o n t e n t s
   // -------------------------------------------------------

   // You can look up objects by name
   RooAbsArg* aptr = s.find("a") ;

   // Construct a subset by name
   RooArgSet* subset1 = (RooArgSet*) s.selectByName("a,b,c") ;

   // Construct asubset by attribute
   RooArgSet* subset2 = (RooArgSet*) s.selectByAttrib("Constant",kTRUE) ;

   // Construct the subset of overlapping contents with another set
   RooArgSet s1(a,b,c) ;
   RooArgSet s2(c,d,e) ;
   RooArgSet* subset3 = (RooArgSet*) s1.selectCommon(s2) ;



   // O w n i n g   R o o A r g S e t s 
   // ---------------------------------  

   // Create a RooArgSet that owns its components
   // A set either owns all of its components or none,
   // so once addOwned() is used, add() can no longer be
   // used and will result in an error message

   RooRealVar* ac = (RooRealVar*) a.clone("a") ;
   RooRealVar* bc = (RooRealVar*) b.clone("b") ;
   RooRealVar* cc = (RooRealVar*) c.clone("c") ;

   RooArgSet s3 ;
   s3.addOwned(RooArgSet(*ac,*bc,*cc)) ;

   // Another possibility is to add an owned clone
   // of an object instead of the original
   s3.addClone(RooArgSet(d,e,g)) ;

   // A clone of a owning set is non-owning and its
   // contents is owned by the originating owning set
   RooArgSet* sclone = (RooArgSet*) s3.Clone("sclone") ;

   // To make a clone of a set and its contents use
   // the snapshot method
   RooArgSet* sclone2 = (RooArgSet*) s3.snapshot() ;

   // If a set contains function objects, only the head node
   // is cloned in a snapshot. To make a snapshot of all
   // servers of a function object do as follows. The result
   // of a RooArgSet snapshot with deepCloning option is a set
   // of cloned objects, and all their clone (recursive) server
   // dependencies, that together form a self-consistent
   // set that is free of external dependencies

   RooArgSet* sclone3 = (RooArgSet*) s3.snapshot(kTRUE) ;



   // S e t   p r i n t i n g 
   // ------------------------

   // Inline printing only show list of names of contained objects
   cout << "sclone = " << (*sclone) << endl ;

   // Plain print shows the same, prefixed by name of the set
   sclone->Print() ;

   // Standard printing shows one line for each item with the items name, class name and value
   sclone->Print("s") ;

   // Verbose printing adds each items arguments, address and 'extras' as defined by the object
   sclone->Print("v") ;



   // U s i n g   R o o A r g L i s t s 
   // ---------------------------------

   // List constructors exists with up to 9 initial arguments
   RooArgList l(a,b,c,d) ;

   // Lists have an explicit order and allow multiple arguments with the same name
   l.add(RooArgList(a,b,c,d)) ;

   // Access by index is provided
   RooAbsArg* arg4 = l.at(4) ;


}