<< "\n";
}
- Float_t tquality=0., zcorr=0.;
+ Float_t tquality;
Double_t kroady = fReconstructor->GetRecoParam() ->GetRoad1y();
Double_t kroadz = fPadLength * .5 + 1.;
+
+ // initialize configuration parameters
+ Float_t zcorr = kZcorr ? fTilt * (fZProb - fZref[0]) : 0.;
+ Int_t niter = kZcorr ? 1 : 2;
+
Double_t yexp, zexp;
Int_t ncl = 0;
-
- // looking for clusters
- for (Int_t iter = 0; iter < 2; iter++) {
+ // start seed update
+ for (Int_t iter = 0; iter < niter; iter++) {
ncl = 0;
- // recalculate correction for tilt pad
- zcorr = (kZcorr&&fN) ? fTilt * (fZProb - fZref[0]) : 0.;
-
for (Int_t iTime = 0; iTime < AliTRDtrackerV1::GetNTimeBins(); iTime++) {
if(!(layer = chamber->GetTB(iTime))) continue;
if(!Int_t(*layer)) continue;
if (zexp < c->GetZ()) zexp = c->GetZ() - fPadLength*0.5;
}
} else zexp = fZref[0] + (kZcorr ? fZref[1] * dxlayer : 0.);
- yexp = fYref[0] + fYref[1]* dxlayer + (kZcorr ? fZref[1] * dxlayer : 0.) + zcorr;
+ yexp = fYref[0] + fYref[1] * dxlayer - zcorr;
// Get and register cluster
Int_t index = layer->SearchNearestCluster(yexp, zexp, kroady, kroadz);
if (index < 0) continue;
AliTRDcluster *cl = (*layer)[index];
-
+
fIndexes[iTime] = layer->GetGlobalIndex(index);
fClusters[iTime] = cl;
fY[iTime] = cl->GetY();
}
AliTRDseed::Update();
- //Fit(kZcorr);
}
if(fReconstructor->GetStreamLevel(AliTRDReconstructor::kTracker)>=7) AliInfo(Form("iter = %d nclFit [%d] = %d", iter, fDet, fN2));
const Float_t clSigma0 = 2.E-2; //[cm]
const Float_t clSlopeQ = -1.19E-2; //[1/cm]
+ // get track direction
+ Double_t y0 = fYref[0];
+ Double_t dydx = fYref[1];
+ Double_t z0 = fZref[0];
+ Double_t dzdx = fZref[1];
+ Double_t yt, zt;
const Int_t kNtb = AliTRDtrackerV1::GetNTimeBins();
AliTRDtrackerV1::AliTRDLeastSquare fitterY, fitterZ;
Double_t convert = 1./TMath::Sqrt(12.);
// book cluster information
- Double_t xc[knTimebins+1], yc[knTimebins], zc[knTimebins+1], sy[knTimebins], sz[knTimebins+1];
+ Double_t xc[knTimebins], yc[knTimebins], zc[knTimebins], sy[knTimebins], sz[knTimebins];
Int_t zRow[knTimebins];
- AliTRDcluster *c = 0x0;
- Int_t nc = 0;
- for (Int_t ic=0; ic<kNtb; ic++) {
+
+
+ fN = 0;
+ AliTRDcluster *c=0x0, **jc = &fClusters[0];
+ for (Int_t ic=0; ic<kNtb; ic++, ++jc) {
zRow[ic] = -1;
xc[ic] = -1.;
yc[ic] = 999.;
zc[ic] = 999.;
sy[ic] = 0.;
sz[ic] = 0.;
- if(!(c = fClusters[ic])) continue;
+ if(!(c = (*jc))) continue;
if(!c->IsInChamber()) continue;
Float_t w = 1.;
if(c->GetNPads()>4) w = .5;
if(c->GetNPads()>5) w = .2;
- zRow[nc] = c->GetPadRow();
- xc[nc] = c->GetX() - fX0;
- yc[nc] = c->GetY();
- zc[nc] = c->GetZ();
+ zRow[fN] = c->GetPadRow();
+ xc[fN] = fX0 - c->GetX();
+ yc[fN] = c->GetY();
+ zc[fN] = c->GetZ();
+
+ // extrapolated y value for the track
+ yt = y0 - xc[fN]*dydx;
+ // extrapolated z value for the track
+ zt = z0 - xc[fN]*dzdx;
+ // tilt correction
+ if(tilt) yc[fN] -= fTilt*(zc[fN] - zt);
+
+ // elaborate cluster error
Float_t qr = c->GetQ() - q0;
- sy[nc] = qr < 0. ? clSigma0*TMath::Exp(clSlopeQ*qr) : clSigma0;
- sz[nc] = fPadLength*convert;
- fitterZ.AddPoint(&xc[nc], zc[nc], sz[nc]);
- nc++;
+ sy[fN] = qr < 0. ? clSigma0*TMath::Exp(clSlopeQ*qr) : clSigma0;
+
+ fitterY.AddPoint(&xc[fN], yc[fN]-yt, sy[fN]);
+
+ sz[fN] = fPadLength*convert;
+ fitterZ.AddPoint(&xc[fN], zc[fN], sz[fN]);
+ fN++;
}
// to few clusters
- if (nc < kClmin) return kFALSE;
-
+ if (fN < kClmin) return kFALSE;
- Int_t zN[2*35];
- Int_t nz = AliTRDtrackerV1::Freq(nc, zRow, zN, kFALSE);
+ // fit XY plane
+ fitterY.Eval();
+ fYfit[0] = y0+fitterY.GetFunctionParameter(0);
+ fYfit[1] = dydx-fitterY.GetFunctionParameter(1);
+
+ // check par row crossing
+ Int_t zN[2*AliTRDseed::knTimebins];
+ Int_t nz = AliTRDtrackerV1::Freq(fN, zRow, zN, kFALSE);
// more than one pad row crossing
if(nz>2) return kFALSE;
-
- // estimate reference parameter at average x
- Double_t y0 = fYref[0];
- Double_t dydx = fYref[1];
- Double_t dzdx = fZref[1];
- zc[nc] = fZref[0];
+
// determine z offset of the fit
+ Float_t zslope = 0.;
Int_t nchanges = 0, nCross = 0;
if(nz==2){ // tracklet is crossing pad row
// Find the break time allowing one chage on pad-rows
// with maximal number of accepted clusters
Int_t padRef = zRow[0];
- for (Int_t ic=1; ic<nc; ic++) {
+ for (Int_t ic=1; ic<fN; ic++) {
if(zRow[ic] == padRef) continue;
// debug
// evaluate parameters of the crossing point
Float_t sx = (xc[ic-1] - xc[ic])*convert;
- xc[nc] = .5 * (xc[ic-1] + xc[ic]);
- zc[nc] = .5 * (zc[ic-1] + zc[ic]);
- sz[nc] = TMath::Max(dzdx * sx, .01);
- dzdx = zc[ic-1] > zc[ic] ? 1. : -1.;
- padRef = zRow[ic];
- nCross = ic;
+ fCross[0] = .5 * (xc[ic-1] + xc[ic]);
+ fCross[2] = .5 * (zc[ic-1] + zc[ic]);
+ fCross[3] = TMath::Max(dzdx * sx, .01);
+ zslope = zc[ic-1] > zc[ic] ? 1. : -1.;
+ padRef = zRow[ic];
+ nCross = ic;
nchanges++;
}
}
// condition on nCross and reset nchanges TODO
if(nchanges==1){
- if(dzdx * fZref[1] < 0.){
+ if(dzdx * zslope < 0.){
AliInfo("tracklet direction does not correspond to the track direction. TODO.");
}
SetBit(kRowCross, kTRUE); // mark pad row crossing
- fCross[0] = xc[nc]; fCross[2] = zc[nc]; fCross[3] = sz[nc];
- fitterZ.AddPoint(&xc[nc], zc[nc], sz[nc]);
+ fitterZ.AddPoint(&fCross[0], fCross[2], fCross[3]);
fitterZ.Eval();
- dzdx = fZref[1]; // we don't trust Parameter[1] ??;
- zc[nc] = fitterZ.GetFunctionParameter(0);
+ //zc[nc] = fitterZ.GetFunctionParameter(0);
+ fCross[1] = fYfit[0] - fCross[0] * fYfit[1];
+ fCross[0] = fX0 - fCross[0];
} else if(nchanges > 1){ // debug
- AliInfo("ERROR in n changes!!!");
+ AliError("N pad row crossing > 1.");
return kFALSE;
}
-
- // estimate deviation from reference direction
- dzdx *= fTilt;
- for (Int_t ic=0; ic<nc; ic++) {
- yc[ic] -= (y0 + xc[ic]*dydx);
- if(tilt) yc[ic] -= fTilt*(xc[ic]*dzdx + (zc[ic] - zc[nc]));
- fitterY.AddPoint(&xc[ic], yc[ic], sy[ic]);
- }
- fitterY.Eval();
- fYfit[0] = y0+fitterY.GetFunctionParameter(0);
- fYfit[1] = dydx+fitterY.GetFunctionParameter(1);
-
- if(nchanges) fCross[1] = fYfit[0] + fCross[0] * fYfit[1];
-
-// printf("\nnz = %d\n", nz);
-// for(int ic=0; ic<35; ic++) printf("%d row[%d]\n", ic, zRow[ic]);
-//
-// for(int ic=0; ic<nz; ic++) printf("%d n[%d]\n", ic, zN[ic]);
+ UpdateUsed();
return kTRUE;
}
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff