1 /**************************************************************************
2 * Copyright(c) 1998-2010 ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
18 /* History of cvs commits:
22 //______________________________________________________
23 // Author : Aleksei Pavlinov; IHEP, Protvino, Russia
25 // Implementation of fit procedure from ALICE-INT-2008-026:
26 // "Time and amplitude reconstruction from sampling
27 // measurements of the PHOS signal profile"
28 // M.Yu.Bogolyubsky and ..
30 // Fit by function en*x*x*exp(-2.*x): x = (t-t0)/tau.
31 // The main goal is fast estimation of amplitude and t0.
34 // --- AliRoot header files ---
35 #include "AliCaloFastAltroFitv0.h"
40 #include <TGraphErrors.h>
45 ClassImp(AliCaloFastAltroFitv0)
47 //____________________________________________________________________________
48 AliCaloFastAltroFitv0::AliCaloFastAltroFitv0()
50 fSig(0),fTau(0),fN(0),fPed(0), fAmp(0),fAmpErr(0),fT0(0),fT0Err(0),fChi2(0.),fNDF(0)
51 ,fNoFit(0),fNfit(0),fTfit(0),fAmpfit(0), fStdFun(0)
55 //____________________________________________________________________________
56 AliCaloFastAltroFitv0::AliCaloFastAltroFitv0(const char* name, const char* title,
57 const Double_t sig, const Double_t tau, const Double_t n)
58 : TNamed(name, title),
59 fSig(sig),fTau(tau),fN(n),fPed(0), fAmp(0),fAmpErr(0),fT0(0),fT0Err(0),fChi2(0.),fNDF(0)
60 ,fNoFit(0),fNfit(0),fTfit(0),fAmpfit(0), fStdFun(0)
62 if(strlen(name)==0) SetName("CaloFastAltroFitv0");
65 //____________________________________________________________________________
66 AliCaloFastAltroFitv0::AliCaloFastAltroFitv0(const AliCaloFastAltroFitv0 &obj)
68 fSig(0),fTau(0),fN(2.),fPed(0), fAmp(0),fAmpErr(0),fT0(0),fT0Err(0),fChi2(0.),fNDF(0)
69 ,fNoFit(0),fNfit(0),fTfit(0),fAmpfit(0), fStdFun(0)
73 //____________________________________________________________________________
74 AliCaloFastAltroFitv0::~AliCaloFastAltroFitv0()
76 if(fTfit) delete [] fTfit;
77 if(fAmpfit) delete [] fAmpfit;
80 //____________________________________________________________________________
81 AliCaloFastAltroFitv0& AliCaloFastAltroFitv0::operator= (const AliCaloFastAltroFitv0 &/*obj*/)
83 // Not implemented yet
87 void AliCaloFastAltroFitv0::FastFit(Int_t* t, Int_t* y, Int_t nPoints, Double_t sig, Double_t tau,
88 Double_t n, Double_t ped, Double_t tMax)
90 // n 2 here and unused
99 CutRightPart(t,y,nPoints,tMax, ii);
103 fTfit = new Double_t[nPoints];
104 fAmpfit = new Double_t[nPoints];
107 DeductPedestal(t,y,nPoints, tau,ped, fTfit,fAmpfit,fNfit);
108 // printf(" n %i : fNfit %i : ped %f \n", n, fNfit, ped);
109 // for(int i=0; i<fNfit; i++)
110 // printf(" i %i : fAmpfit %7.2f : fTfit %7.2f \n", i, fAmpfit[i], fTfit[i]);
113 FastFit(fTfit,fAmpfit,fNfit,sig,tau, fAmp,fAmpErr, fT0,fT0Err,fChi2);
122 Reset(); // What to do here => fT0 = fTfit[0]; fAmp = fAmpFit[0] ??
128 //____________________________________________________________________________
129 void AliCaloFastAltroFitv0::FastFit(TH1F* h, Double_t sig, Double_t tau, Double_t n,
130 Double_t ped, Double_t tMax)
132 // Service method for convinience only
133 // h - hist with altro response
137 Int_t nPoints = h->GetNbinsX();
138 if(nPoints<2) return; // Sep 07, 09
140 Int_t* t = new Int_t[nPoints];
141 Int_t* y = new Int_t[nPoints];
143 for(Int_t i=0; i<nPoints; i++) {
145 y[i] = Int_t(h->GetBinContent(i+1));
149 FastFit(t,y,nPoints, sig,tau,n,ped, tMax);
151 if(fChi2<=0.0) fNoFit++;
157 void AliCaloFastAltroFitv0::Reset()
161 fAmp = fAmpErr = fT0 = fT0Err = 0.0;
165 if(fTfit) delete [] fTfit;
166 if(fAmpfit) delete [] fAmpfit;
171 void AliCaloFastAltroFitv0::GetFitResult(Double_t &,Double_t &eamp,Double_t &t0,Double_t &et0,
172 Double_t &chi2, Int_t &ndf) const
174 // Return results of fitting procedure
183 void AliCaloFastAltroFitv0::GetFittedPoints(Int_t &nfit, Double_t* ar[2]) const
192 void AliCaloFastAltroFitv0::CutRightPart(Int_t *t,Int_t *y,Int_t nPoints,Double_t tMax, Int_t &ii)
194 // Cut right part of altro sample : static function
196 for(Int_t i=0; i<nPoints; i++) {
198 if(tMax && tt <= Int_t(tMax)) {
204 if(0) printf(" ii %i -> ii %i : tMax %7.2f \n", nPoints, ii, tMax);
207 void AliCaloFastAltroFitv0::DeductPedestal(Int_t* t, Int_t* y, Int_t nPoints, Double_t tau, Double_t ped,
208 Double_t* tn, Double_t* yn, Int_t &nPointsOut)
210 // Pedestal deduction if ped is positive : static function
211 // Discard part od samle if it is not compact.
212 static Double_t yMinUnderPed=2.; // should be tune
213 Int_t ymax=0, nmax=0;
214 for(Int_t i=0; i<nPoints; i++){
220 Int_t i1 = nmax - Int_t(tau);
226 Double_t yd=0.0, tdiff=0.0;;
227 for(Int_t i=i1; i<i2; i++) {
229 yd = Double_t(y[i]) - ped;
233 if(yd < yMinUnderPed) continue;
235 if(i>i1 && nPointsOut>0){
236 tdiff = t[i] - tn[nPointsOut-1];
237 // printf(" i %i : nPointsOut %i : tdiff %6.2f : tn[nPointsOut] %6.2f \n", i,nPointsOut, tdiff, tn[nPointsOut-1]);
239 // discard previous points if its are before maximum point and with gap>1
241 nPointsOut = 0; // nPointsOut--;
242 // if point with gap after maximum - finish selection
243 } else if(i>=nmax ) {
247 // Far away from maximum
248 //if(i-nmax > Int_t(5*tau)) break;
250 tn[nPointsOut] = Double_t(t[i]);
252 //printf("i %i : nPointsOut %i : tn %6.2f : yn %6.2f \n", i, nPointsOut, tn[nPointsOut], yn[nPointsOut]);
255 //printf(" nmax %i : nPointsIn %i :nPointsOut %i i1 %i \n", nmax, nPointsIn, nPointsOut, i1);
258 void AliCaloFastAltroFitv0::FastFit(const Double_t* t, const Double_t* y, const Int_t nPoints,
259 const Double_t sig, const Double_t tau,
260 Double_t &, Double_t &eamp, Double_t &t0, Double_t &et0, Double_t &chi2)
263 // It is case of n=k=2 : fnn = x*x*exp(2 - 2*x)
265 //nPoints - number of points
266 // t[] - array of time bins
267 // y[] - array of amplitudes after pedestal subtractions;
268 // sig - error of amplitude measurement (one value for all channels)
269 // tau - filter time response (in timebin units)
271 // amp - amplitude at t0;
272 // eamp - error of amplitude;
273 // t0 - time of max amplitude;
274 // et0 - error of t0;
276 static Double_t xx; // t/tau
277 static Double_t a, b, c;
278 static Double_t f02, f12, f22; // functions
279 static Double_t f02d, f12d, f22d; // functions derivations
284 printf(" AliCaloFastAltroFitv0::FastFit : nPoints<=%i \n", nPoints);
289 for(Int_t i=0; i<nPoints; i++){
297 f22d = 2.*(f12 - f22);
303 Double_t t01=0.0, t02=0.0;
304 Double_t amp1=0.0, amp2=0.0, chi21=0.0, chi22=0.0;
305 if(QuadraticRoots(a,b,c, t01,t02)) {
308 Amplitude(t,y,nPoints, sig, tau, t01, amp1, chi21);
309 Amplitude(t,y,nPoints, sig, tau, t02, amp2, chi22);
311 printf(" t01 %f : t02 %f \n", t01, t02);
312 printf(" amp1 %f : amp2 %f \n", amp1, amp2);
313 printf(" chi21 %f : chi22 %f \n", chi21, chi22);
315 // t0 less on one tau with comparing with value from "canonical equation"
324 if(tau<3.) { // EMCAL case : small tau
325 t0 += -0.03; // Discard bias in t0
326 Amplitude(t,y,nPoints, sig, tau, t0, amp, chi2);
328 CalculateParsErrors(t, y, nPoints, sig, tau, amp, t0, eamp, et0);
332 // DrawFastFunction(amp, t0, fUtils->GetPedestalValue(), "1");
333 // DrawFastFunction(amp1, t01, fUtils->GetPedestalValue(), "1");
334 // DrawFastFunction(amp2, t02, fUtils->GetPedestalValue(), "2");
336 chi2 = t01; // no roots, bad fit - negative chi2
340 Bool_t AliCaloFastAltroFitv0::QuadraticRoots(const Double_t a, const Double_t b, const Double_t c,
341 Double_t &x1, Double_t &x2)
343 // Resolve quadratic equations a*x**2 + b*x + c
344 //printf(" a %12.5e b %12.5e c %12.5e \n", a, b, c);
345 static Double_t dtmp = 0.0, dtmpCut = -1.e-6;
346 static Int_t iWarning=0, iNoSolution=0;
349 if(dtmp>=dtmpCut && dtmp<0.0) {
350 if(iWarning<5 || iWarning%1000==0)
351 printf("<W> %i small neg. sq. : dtmp %12.5e \n", iWarning, dtmp);
357 x1 = (-b + dtmp) / (2.*a);
358 x2 = (-b - dtmp) / (2.*a);
360 // printf(" x1 %f : x2 %f \n", x1, x2);
364 if(iNoSolution<5 || iNoSolution%1000==0)
365 printf("<No solution> %i neg. sq. : dtmp %12.5e \n", iNoSolution, dtmp);
371 void AliCaloFastAltroFitv0::Amplitude(const Double_t* t,const Double_t* y,const Int_t nPoints,
372 const Double_t sig, const Double_t tau, const Double_t t0,
373 Double_t &, Double_t &chi2)
375 // Calculate parameters error too - Mar 24,09
376 // sig is independent from points
378 Double_t x=0.0, f=0.0, den=0.0, f02;
379 for(Int_t i=0; i<nPoints; i++){
386 if(den>0.0) amp /= den;
392 for(Int_t i=0; i<nPoints; i++){
398 // printf(" %i : y %f -> f %f : dy %f \n", i, y[i], f, dy);
403 void AliCaloFastAltroFitv0::CalculateParsErrors(const Double_t* t, const Double_t* /*y*/, const Int_t nPoints,
404 const Double_t sig, const Double_t tau,
405 Double_t &, Double_t &t0, Double_t &eamp, Double_t &et0)
407 // Remember that fmax = exp(-n);
408 // fmax_nk = (n/k)**n*exp(-n) => n=k=2 => exp(-n) = exp(-2.)
409 static Double_t cc = exp(-2.);
410 // static Double_t cc = exp(-fN); // mean(N)~1.5 ??
412 Double_t sumf2=0.0, sumfd2=0.0, x, f02, f12, f22, f22d;
414 for(Int_t i=0; i<nPoints; i++){
421 f22d = 2.*(f12 - f22);
422 sumfd2 += f22d * f22d;
424 et0 = (sig/amp)/sqrt(sumfd2);
425 eamp = sig/sqrt(sumf2);
434 TCanvas* AliCaloFastAltroFitv0::DrawFastFunction()
437 if(fNfit<=0) return 0; // no points
439 static TCanvas *c = 0;
441 c = new TCanvas("fastFun","fastFun",800,600);
446 Double_t* eamp = new Double_t[fNfit];
447 Double_t* et = new Double_t[fNfit];
449 for(Int_t i=0; i<fNfit; i++) {
454 TGraphErrors *gr = new TGraphErrors(fNfit, fTfit,fAmpfit, et,eamp);
456 gr->SetTitle(Form("Fast Fit : #chi^{2}/ndf = %8.2f / %i", GetChi2(), GetNDF()));
457 gr->GetHistogram()->SetXTitle(" time bin ");
458 gr->GetHistogram()->SetYTitle(" amplitude ");
461 fStdFun = new TF1("stdFun", StdResponseFunction, 0., fTfit[fNfit-1]+2., 5);
462 fStdFun->SetParNames("amp","t0","tau","N","ped");
464 fStdFun->SetParameter(0, GetEnergy());
465 fStdFun->SetParameter(1, GetTime() + GetTau());
466 fStdFun->SetParameter(2, GetTau()); //
467 fStdFun->SetParameter(3, GetN()); // 2
468 fStdFun->SetParameter(4, 0.); //
470 fStdFun->SetLineColor(kBlue);
471 fStdFun->SetLineWidth(1);
473 fStdFun->Draw("same");
483 Double_t AliCaloFastAltroFitv0::StdResponseFunction(const Double_t *x, const Double_t *par)
485 // Static Standard Response Function :
486 // look to Double_t AliEMCALRawUtils::RawResponseFunction(Double_t *x, Double_t *par)
487 // Using for drawing only.
489 // Shape of the electronics raw reponse:
490 // It is a semi-gaussian, 2nd order Gamma function (n=2) of the general form
492 // t' = (t - t0 + tau) / tau
493 // F = A * t**N * exp( N * ( 1 - t) ) for t >= 0
497 // A: par[0] // Amplitude = peak value
503 static Double_t signal , tau, n, ped, xx;
508 xx = ( x[0] - par[1] + tau ) / tau ;
513 signal = ped + par[0] * TMath::Power(xx , n) * TMath::Exp(n * (1 - xx )) ;