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RooBinIntegrator.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 RooBinIntegrator.cxx
19\class RooBinIntegrator
20\ingroup Roofitcore
21
22RooBinIntegrator implements an adaptive one-dimensional
23numerical integration algorithm.
24**/
25
26
27#include "RooFit.h"
28#include "Riostream.h"
29
30#include "TClass.h"
31#include "RooBinIntegrator.h"
32#include "RooArgSet.h"
33#include "RooRealVar.h"
34#include "RooNumber.h"
36#include "RooNumIntConfig.h"
37#include "RooNumIntFactory.h"
38#include "RooMsgService.h"
39
40#include <assert.h>
41
42
43
44using namespace std;
45
47;
48
49// Register this class with RooNumIntConfig
50
51////////////////////////////////////////////////////////////////////////////////
52/// Register RooBinIntegrator, is parameters and capabilities with RooNumIntFactory
53
55{
56 RooRealVar numBins("numBins","Number of bins in range",100) ;
58 fact.storeProtoIntegrator(proto,RooArgSet(numBins)) ;
60}
61
62
63
64////////////////////////////////////////////////////////////////////////////////
65/// Default constructor
66
67RooBinIntegrator::RooBinIntegrator() : _numBins(0), _useIntegrandLimits(kFALSE), _x(0)
68{
69}
70
71
72////////////////////////////////////////////////////////////////////////////////
73/// Construct integrator on given function binding binding
74
77{
79 assert(0 != integrand() && integrand()->isValid());
80
81 // Allocate coordinate buffer size after number of function dimensions
83 _numBins = 100 ;
84
85 _xmin.resize(_function->getDimension()) ;
86 _xmax.resize(_function->getDimension()) ;
87
88 for (UInt_t i=0 ; i<_function->getDimension() ; i++) {
89 _xmin[i]= integrand()->getMinLimit(i);
90 _xmax[i]= integrand()->getMaxLimit(i);
91
92 // Retrieve bin configuration from integrand
93 list<Double_t>* tmp = integrand()->binBoundaries(i) ;
94 if (!tmp) {
95 oocoutW((TObject*)0,Integration) << "RooBinIntegrator::RooBinIntegrator WARNING: integrand provide no binning definition observable #"
96 << i << " substituting default binning of " << _numBins << " bins" << endl ;
97 tmp = new list<Double_t> ;
98 for (Int_t j=0 ; j<=_numBins ; j++) {
99 tmp->push_back(_xmin[i]+j*(_xmax[i]-_xmin[i])/_numBins) ;
100 }
101 }
102 _binb.push_back(tmp) ;
103 }
104 checkLimits();
105
106}
107
108
109////////////////////////////////////////////////////////////////////////////////
110/// Construct integrator on given function binding binding
111
113 RooAbsIntegrator(function), _binb(0)
114{
115 const RooArgSet& configSet = config.getConfigSection(IsA()->GetName()) ;
117 _numBins = (Int_t) configSet.getRealValue("numBins") ;
118 assert(0 != integrand() && integrand()->isValid());
119
120 // Allocate coordinate buffer size after number of function dimensions
122
123 for (UInt_t i=0 ; i<_function->getDimension() ; i++) {
124 _xmin.push_back(integrand()->getMinLimit(i));
125 _xmax.push_back(integrand()->getMaxLimit(i));
126
127 // Retrieve bin configuration from integrand
128 list<Double_t>* tmp = integrand()->binBoundaries(i) ;
129 if (!tmp) {
130 oocoutW((TObject*)0,Integration) << "RooBinIntegrator::RooBinIntegrator WARNING: integrand provide no binning definition observable #"
131 << i << " substituting default binning of " << _numBins << " bins" << endl ;
132 tmp = new list<Double_t> ;
133 for (Int_t j=0 ; j<=_numBins ; j++) {
134 tmp->push_back(_xmin[i]+j*(_xmax[i]-_xmin[i])/_numBins) ;
135 }
136 }
137 _binb.push_back(tmp) ;
138 }
139
140 checkLimits();
141}
142
143
144////////////////////////////////////////////////////////////////////////////////
145/// Clone integrator with new function binding and configuration. Needed by RooNumIntFactory
146
148{
149 return new RooBinIntegrator(function,config) ;
150}
151
152
153
154
155
156////////////////////////////////////////////////////////////////////////////////
157/// Destructor
158
160{
161 if(_x) delete[] _x;
162 for (vector<list<Double_t>*>::iterator iter = _binb.begin() ; iter!=_binb.end() ; ++iter) {
163 delete (*iter) ;
164 }
165
166}
167
168
169////////////////////////////////////////////////////////////////////////////////
170/// Change our integration limits. Return kTRUE if the new limits are
171/// ok, or otherwise kFALSE. Always returns kFALSE and does nothing
172/// if this object was constructed to always use our integrand's limits.
173
175{
177 oocoutE((TObject*)0,Integration) << "RooBinIntegrator::setLimits: cannot override integrand's limits" << endl;
178 return kFALSE;
179 }
180 _xmin[0]= *xmin;
181 _xmax[0]= *xmax;
182 return checkLimits();
183}
184
185
186////////////////////////////////////////////////////////////////////////////////
187/// Check that our integration range is finite and otherwise return kFALSE.
188/// Update the limits from the integrand if requested.
189
191{
193 assert(0 != integrand() && integrand()->isValid());
194 _xmin.resize(_function->getDimension()) ;
195 _xmax.resize(_function->getDimension()) ;
196 for (UInt_t i=0 ; i<_function->getDimension() ; i++) {
197 _xmin[i]= integrand()->getMinLimit(i);
198 _xmax[i]= integrand()->getMaxLimit(i);
199 }
200 }
201 for (UInt_t i=0 ; i<_function->getDimension() ; i++) {
202 if (_xmax[i]<=_xmin[i]) {
203 oocoutE((TObject*)0,Integration) << "RooBinIntegrator::checkLimits: bad range with min >= max (_xmin = " << _xmin[i] << " _xmax = " << _xmax[i] << ")" << endl;
204 return kFALSE;
205 }
207 return kFALSE ;
208 }
209 }
210
211 return kTRUE;
212}
213
214
215////////////////////////////////////////////////////////////////////////////////
216/// Calculate numeric integral at given set of function binding parameters
217
219{
220 assert(isValid());
221
222 double sum = 0. ;
223
224 if (_function->getDimension()==1) {
225 list<Double_t>::iterator iter = _binb[0]->begin() ;
226 Double_t xlo = *iter ; ++iter ;
227 for (; iter!=_binb[0]->end() ; ++iter) {
228 Double_t xhi = *iter ;
229 Double_t xcenter = (xhi+xlo)/2 ;
230 Double_t binInt = integrand(xvec(xcenter))*(xhi-xlo) ;
231 sum += binInt ;
232 //cout << "RBI::integral over " << _function->getName() << " 1D binInt[" << xcenter << "] = " << binInt << " running sum = " << sum << endl ;
233 xlo=xhi ;
234 }
235 }
236
237 if (_function->getDimension()==2) {
238
239 list<Double_t>::iterator iter1 = _binb[0]->begin() ;
240
241 Double_t x1lo = *iter1 ; ++iter1 ;
242 for (; iter1!=_binb[0]->end() ; ++iter1) {
243
244 Double_t x1hi = *iter1 ;
245 Double_t x1center = (x1hi+x1lo)/2 ;
246
247 list<Double_t>::iterator iter2 = _binb[1]->begin() ;
248 Double_t x2lo = *iter2 ; ++iter2 ;
249 for (; iter2!=_binb[1]->end() ; ++iter2) {
250
251 Double_t x2hi = *iter2 ;
252 Double_t x2center = (x2hi+x2lo)/2 ;
253
254 Double_t binInt = integrand(xvec(x1center,x2center))*(x1hi-x1lo)*(x2hi-x2lo) ;
255 //cout << "RBI::integral 2D binInt[" << x1center << "," << x2center << "] = " << binInt << " binv = " << (x1hi-x1lo) << "*" << (x2hi-x2lo) << endl ;
256 sum += binInt ;
257 x2lo=x2hi ;
258 }
259 x1lo=x1hi ;
260 }
261 }
262
263 if (_function->getDimension()==3) {
264
265 list<Double_t>::iterator iter1 = _binb[0]->begin() ;
266
267 Double_t x1lo = *iter1 ; ++iter1 ;
268 for (; iter1!=_binb[0]->end() ; ++iter1) {
269
270 Double_t x1hi = *iter1 ;
271 Double_t x1center = (x1hi+x1lo)/2 ;
272
273 list<Double_t>::iterator iter2 = _binb[1]->begin() ;
274 Double_t x2lo = *iter2 ; ++iter2 ;
275 for (; iter2!=_binb[1]->end() ; ++iter2) {
276
277 Double_t x2hi = *iter2 ;
278 Double_t x2center = (x2hi+x2lo)/2 ;
279
280 list<Double_t>::iterator iter3 = _binb[2]->begin() ;
281 Double_t x3lo = *iter3 ; ++iter3 ;
282 for (; iter3!=_binb[2]->end() ; ++iter3) {
283
284 Double_t x3hi = *iter3 ;
285 Double_t x3center = (x3hi+x3lo)/2 ;
286
287 Double_t binInt = integrand(xvec(x1center,x2center,x3center))*(x1hi-x1lo)*(x2hi-x2lo)*(x3hi-x3lo) ;
288 //cout << "RBI::integral 3D binInt[" << x1center << "," << x2center << "," << x3center << "] = " << binInt << endl ;
289 sum += binInt ;
290
291 x3lo=x3hi ;
292 }
293 x2lo=x2hi ;
294 }
295 x1lo=x1hi ;
296 }
297 }
298
299 return sum;
300}
301
302
#define oocoutW(o, a)
Definition: RooMsgService.h:47
#define oocoutE(o, a)
Definition: RooMsgService.h:48
int Int_t
Definition: RtypesCore.h:43
const Bool_t kFALSE
Definition: RtypesCore.h:90
const Bool_t kTRUE
Definition: RtypesCore.h:89
#define ClassImp(name)
Definition: Rtypes.h:361
float xmin
Definition: THbookFile.cxx:93
float xmax
Definition: THbookFile.cxx:93
const char * proto
Definition: civetweb.c:16604
Double_t getRealValue(const char *name, Double_t defVal=0, Bool_t verbose=kFALSE) const
Get value of a RooAbsReal stored in set with given name.
Abstract interface for evaluating a real-valued function of one real variable and performing numerica...
Definition: RooAbsFunc.h:23
virtual Double_t getMinLimit(UInt_t dimension) const =0
virtual std::list< Double_t > * binBoundaries(Int_t) const
Definition: RooAbsFunc.h:64
virtual Double_t getMaxLimit(UInt_t dimension) const =0
UInt_t getDimension() const
Definition: RooAbsFunc.h:29
RooAbsIntegrator is the abstract interface for integrators of real-valued functions that implement th...
const RooAbsFunc * _function
const RooAbsFunc * integrand() const
Bool_t isValid() const
RooArgSet is a container object that can hold multiple RooAbsArg objects.
Definition: RooArgSet.h:28
RooBinIntegrator implements an adaptive one-dimensional numerical integration algorithm.
std::vector< std::list< Double_t > * > _binb
Upper integration bound.
std::vector< Double_t > _xmin
static void registerIntegrator(RooNumIntFactory &fact)
Register RooBinIntegrator, is parameters and capabilities with RooNumIntFactory.
Double_t * xvec(Double_t &xx)
Int_t _numBins
list of bin boundaries
std::vector< Double_t > _xmax
Lower integration bound.
virtual ~RooBinIntegrator()
Destructor.
Bool_t _useIntegrandLimits
Size of integration range.
virtual RooAbsIntegrator * clone(const RooAbsFunc &function, const RooNumIntConfig &config) const
Clone integrator with new function binding and configuration. Needed by RooNumIntFactory.
virtual Bool_t checkLimits() const
Check that our integration range is finite and otherwise return kFALSE.
virtual Double_t integral(const Double_t *yvec=0)
Calculate numeric integral at given set of function binding parameters.
Bool_t setLimits(Double_t *xmin, Double_t *xmax)
Change our integration limits.
RooBinIntegrator()
Default constructor.
virtual Bool_t setLabel(const char *label, bool printError=true) override
Set value by specifying the name of the desired state.
RooNumIntConfig holds the configuration parameters of the various numeric integrators used by RooReal...
const RooArgSet & getConfigSection(const char *name) const
Retrieve configuration information specific to integrator with given name.
RooCategory & method1D()
static RooNumIntConfig & defaultConfig()
Return reference to instance of default numeric integrator configuration object.
RooNumIntFactory is a factory to instantiate numeric integrators from a given function binding and a ...
Bool_t storeProtoIntegrator(RooAbsIntegrator *proto, const RooArgSet &defConfig, const char *depName="")
Method accepting registration of a prototype numeric integrator along with a RooArgSet of its default...
static Int_t isInfinite(Double_t x)
Return true if x is infinite by RooNumBer internal specification.
Definition: RooNumber.cxx:58
RooRealVar represents a variable that can be changed from the outside.
Definition: RooRealVar.h:35
Mother of all ROOT objects.
Definition: TObject.h:37
virtual const char * GetName() const
Returns name of object.
Definition: TObject.cxx:357
void function(const Char_t *name_, T fun, const Char_t *docstring=0)
Definition: RExports.h:151
@ Integration
Definition: RooGlobalFunc.h:67
static long int sum(long int i)
Definition: Factory.cxx:2275