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RooGenericPdf.cxx
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1/*****************************************************************************
2 * Project: RooFit *
3 * Package: RooFitCore *
4 * @(#)root/roofitcore:$Id$
5 * Authors: *
6 * WV, Wouter Verkerke, UC Santa Barbara, verkerke@slac.stanford.edu *
7 * DK, David Kirkby, UC Irvine, dkirkby@uci.edu *
8 * *
9 * Copyright (c) 2000-2005, Regents of the University of California *
10 * and Stanford University. All rights reserved. *
11 * *
12 * Redistribution and use in source and binary forms, *
13 * with or without modification, are permitted according to the terms *
14 * listed in LICENSE (http://roofit.sourceforge.net/license.txt) *
15 *****************************************************************************/
16
17/**
18\file RooGenericPdf.cxx
19\class RooGenericPdf
20\ingroup Roofitcore
21
22RooGenericPdf is a concrete implementation of a probability density function,
23which takes a RooArgList of servers and a C++ expression string defining how
24its value should be calculated from the given list of servers.
25A fully numerical integration is automatically performed to normalize the given
26expression. RooGenericPdf uses a RooFormula object to perform the expression evaluation.
27
28The string expression can be any valid TFormula expression referring to the
29listed servers either by name or by their ordinal list position. These three are
30equivalent:
31```
32 RooFormulaVar("gen", "x*y", RooArgList(x,y)) // reference by name
33 RooFormulaVar("gen", "@0*@1", RooArgList(x,y)) // reference by ordinal with @
34 RooFormulaVar("gen", "x[0]*x[1]", RooArgList(x,y)) // TFormula-builtin reference by ordinal
35```
36Note that `x[i]` is an expression reserved for TFormula. All variable references
37are automatically converted to the TFormula-native format. If a variable with
38the name `x` is given, the RooFormula interprets `x[i]` as a list position,
39but `x` without brackets as the name of a RooFit object.
40
41The last two versions, while slightly less readable, are more versatile because
42the names of the arguments are not hard coded.
43**/
44
45#include "RooFit.h"
46#include "Riostream.h"
47
48#include "RooGenericPdf.h"
49#include "RooStreamParser.h"
50#include "RooMsgService.h"
51#include "RooArgList.h"
52
53
54
55using namespace std;
56
58
59
60
61////////////////////////////////////////////////////////////////////////////////
62/// Constructor with formula expression and list of input variables
63
64RooGenericPdf::RooGenericPdf(const char *name, const char *title, const RooArgList& dependents) :
65 RooAbsPdf(name,title),
66 _actualVars("actualVars","Variables used by PDF expression",this),
67 _formExpr(title)
68{
69 _actualVars.add(dependents) ;
70 formula();
71
72 if (_actualVars.getSize()==0) _value = traceEval(0) ;
73}
74
75
76
77////////////////////////////////////////////////////////////////////////////////
78/// Constructor with a name, title, formula expression and a list of variables
79
80RooGenericPdf::RooGenericPdf(const char *name, const char *title,
81 const char* inFormula, const RooArgList& dependents) :
82 RooAbsPdf(name,title),
83 _actualVars("actualVars","Variables used by PDF expression",this),
84 _formExpr(inFormula)
85{
86 _actualVars.add(dependents) ;
87 formula();
88
89 if (_actualVars.getSize()==0) _value = traceEval(0) ;
90}
91
92
93
94////////////////////////////////////////////////////////////////////////////////
95/// Copy constructor
96
97RooGenericPdf::RooGenericPdf(const RooGenericPdf& other, const char* name) :
98 RooAbsPdf(other, name),
99 _actualVars("actualVars",this,other._actualVars),
100 _formExpr(other._formExpr)
101{
102 formula();
103}
104
105
106////////////////////////////////////////////////////////////////////////////////
107
109{
110 if (!_formula) {
111 const_cast<std::unique_ptr<RooFormula>&>(_formula).reset(
113 const_cast<TString&>(_formExpr) = _formula->formulaString().c_str();
114 }
115 return *_formula ;
116}
117
118
119
120////////////////////////////////////////////////////////////////////////////////
121/// Calculate current value of this object
122
124{
125 return formula().eval(_normSet) ;
126}
127
128
129
130////////////////////////////////////////////////////////////////////////////////
131/// Change formula expression to given expression
132
133Bool_t RooGenericPdf::setFormula(const char* inFormula)
134{
135 if (formula().reCompile(inFormula)) return kTRUE ;
136
137 _formExpr = inFormula ;
138 setValueDirty() ;
139 return kFALSE ;
140}
141
142
143
144////////////////////////////////////////////////////////////////////////////////
145/// Check if given value is valid
146
147Bool_t RooGenericPdf::isValidReal(Double_t /*value*/, Bool_t /*printError*/) const
148{
149 return kTRUE ;
150}
151
152
153
154////////////////////////////////////////////////////////////////////////////////
155/// Propagate server changes to embedded formula object
156
157Bool_t RooGenericPdf::redirectServersHook(const RooAbsCollection& newServerList, Bool_t mustReplaceAll, Bool_t nameChange, Bool_t /*isRecursive*/)
158{
159 if (_formula) {
160 return _formula->changeDependents(newServerList,mustReplaceAll,nameChange);
161 } else {
162 return kTRUE ;
163 }
164}
165
166
167
168////////////////////////////////////////////////////////////////////////////////
169/// Print info about this object to the specified stream.
170
172{
174 if (verbose) {
175 os << " --- RooGenericPdf --- " << endl ;
176 indent.Append(" ");
177 os << indent ;
178 formula().printMultiline(os,content,verbose,indent);
179 }
180}
181
182
183
184////////////////////////////////////////////////////////////////////////////////
185/// Add formula expression as meta argument in printing interface
186
187void RooGenericPdf::printMetaArgs(ostream& os) const
188{
189 os << "formula=\"" << _formExpr << "\" " ;
190}
191
192
193
194////////////////////////////////////////////////////////////////////////////////
195/// Read object contents from given stream
196
197Bool_t RooGenericPdf::readFromStream(istream& is, Bool_t compact, Bool_t /*verbose*/)
198{
199 if (compact) {
200 coutE(InputArguments) << "RooGenericPdf::readFromStream(" << GetName() << "): can't read in compact mode" << endl ;
201 return kTRUE ;
202 } else {
203 RooStreamParser parser(is) ;
204 return setFormula(parser.readLine()) ;
205 }
206}
207
208
209////////////////////////////////////////////////////////////////////////////////
210/// Write object contents to given stream
211
212void RooGenericPdf::writeToStream(ostream& os, Bool_t compact) const
213{
214 if (compact) {
215 os << getVal() << endl ;
216 } else {
217 os << GetTitle() ;
218 }
219}
220
221
222
#define coutE(a)
Definition: RooMsgService.h:33
int Int_t
Definition: RtypesCore.h:43
const Bool_t kFALSE
Definition: RtypesCore.h:90
bool Bool_t
Definition: RtypesCore.h:61
double Double_t
Definition: RtypesCore.h:57
const Bool_t kTRUE
Definition: RtypesCore.h:89
#define ClassImp(name)
Definition: Rtypes.h:361
static void indent(ostringstream &buf, int indent_level)
char name[80]
Definition: TGX11.cxx:109
void setValueDirty()
Mark the element dirty. This forces a re-evaluation when a value is requested.
Definition: RooAbsArg.h:487
RooAbsCollection is an abstract container object that can hold multiple RooAbsArg objects.
Int_t getSize() const
virtual void printMultiline(std::ostream &os, Int_t contents, Bool_t verbose=kFALSE, TString indent="") const
Print multi line detailed information of this RooAbsPdf.
Definition: RooAbsPdf.cxx:1971
RooArgSet * _normSet
Normalization integral (owned by _normMgr)
Definition: RooAbsPdf.h:321
Double_t traceEval(const RooArgSet *set) const
Calculate current value of object, with error tracing wrapper.
Definition: RooAbsReal.cxx:339
Double_t _value
Definition: RooAbsReal.h:449
Double_t getVal(const RooArgSet *normalisationSet=nullptr) const
Evaluate object.
Definition: RooAbsReal.h:90
RooArgList is a container object that can hold multiple RooAbsArg objects.
Definition: RooArgList.h:21
RooFormula internally uses ROOT's TFormula to compute user-defined expressions of RooAbsArgs.
Definition: RooFormula.h:28
Double_t eval(const RooArgSet *nset=0) const
Evalute all parameters/observables, and then evaluate formula.
Definition: RooFormula.cxx:340
void printMultiline(std::ostream &os, Int_t contents, Bool_t verbose=kFALSE, TString indent="") const
Printing interface.
Definition: RooFormula.cxx:369
RooGenericPdf is a concrete implementation of a probability density function, which takes a RooArgLis...
Definition: RooGenericPdf.h:25
void printMultiline(std::ostream &os, Int_t content, Bool_t verbose=kFALSE, TString indent="") const
Print info about this object to the specified stream.
Bool_t setFormula(const char *formula)
Change formula expression to given expression.
virtual Double_t evaluate() const
Calculate current value of this object.
virtual void writeToStream(std::ostream &os, Bool_t compact) const
Write object contents to given stream.
void printMetaArgs(std::ostream &os) const
Add formula expression as meta argument in printing interface.
RooListProxy _actualVars
Definition: RooGenericPdf.h:50
std::unique_ptr< RooFormula > _formula
Definition: RooGenericPdf.h:60
virtual Bool_t redirectServersHook(const RooAbsCollection &newServerList, Bool_t mustReplaceAll, Bool_t nameChange, Bool_t isRecursive)
Propagate server changes to embedded formula object.
virtual Bool_t isValidReal(Double_t value, Bool_t printError) const
Check if given value is valid.
RooFormula & formula() const
TString _formExpr
Formula engine.
Definition: RooGenericPdf.h:61
virtual Bool_t readFromStream(std::istream &is, Bool_t compact, Bool_t verbose=kFALSE)
Read object contents from given stream.
virtual Bool_t add(const RooAbsArg &var, Bool_t silent=kFALSE)
Reimplementation of standard RooArgList::add()
TString readLine()
Read an entire line from the stream and return as TString This method recognizes the use of '\' in th...
virtual const char * GetTitle() const
Returns title of object.
Definition: TNamed.h:48
virtual const char * GetName() const
Returns name of object.
Definition: TNamed.h:47
Basic string class.
Definition: TString.h:131
const char * Data() const
Definition: TString.h:364
@ InputArguments
Definition: RooGlobalFunc.h:68