alpha=t.GetAlpha();
//
//circle parameters
+ //PH Sometimes fP4 and fHelix[4] are very big and the calculation
+ //PH of the Sqrt cannot be done. To be investigated...
fHelix[4]=fHelix[4]/t.GetConvConst(); // C
cs=TMath::Cos(alpha); sn=TMath::Sin(alpha);
Double_t xc, yc, rc;
rc = 1/fHelix[4];
xc = x-fHelix[2]*rc;
- yc = fHelix[0]+TMath::Sqrt(1-(x-xc)*(x-xc)*fHelix[4]*fHelix[4])/fHelix[4];
+ Double_t dummy = 1-(x-xc)*(x-xc)*fHelix[4]*fHelix[4];
+ if (dummy<0) {
+ AliError(Form("The argument of the Sqrt is %f => set to 0\n",dummy));
+ dummy = 0;
+ }
+ yc = fHelix[0]+TMath::Sqrt(dummy)/fHelix[4];
fHelix[6] = xc*cs - yc*sn;
fHelix[7] = xc*sn + yc*cs;
alpha=t.GetAlpha();
//
//circle parameters
+ //PH Sometimes fP4 and fHelix[4] are very big and the calculation
+ //PH of the Sqrt cannot be done. To be investigated...
fHelix[4]=fHelix[4]/AliKalmanTrack::GetConvConst(); // C
cs=TMath::Cos(alpha); sn=TMath::Sin(alpha);
Double_t xc, yc, rc;
rc = 1/fHelix[4];
xc = x-fHelix[2]*rc;
- yc = fHelix[0]+TMath::Sqrt(1-(x-xc)*(x-xc)*fHelix[4]*fHelix[4])/fHelix[4];
+ Double_t dummy = 1-(x-xc)*(x-xc)*fHelix[4]*fHelix[4];
+ if (dummy<0) {
+ AliError(Form("The argument of the Sqrt is %f => set to 0\n",dummy));
+ dummy = 0;
+ }
+ yc = fHelix[0]+TMath::Sqrt(dummy)/fHelix[4];
fHelix[6] = xc*cs - yc*sn;
fHelix[7] = xc*sn + yc*cs;