Double_t b[3] = {0.,0.,0.};
TGeoGlobalMagField::Instance()->Field(x,b);
fgSimpleBValue = b[0];
- fgFieldON = fgSimpleBValue ? kTRUE : kFALSE;
+ fgFieldON = (TMath::Abs(fgSimpleBValue) > 1.e-10) ? kTRUE : kFALSE;
}
// Extrapolation loop (until within tolerance or the track turn around)
Double_t residue = zEnd - trackParam->GetZ();
Bool_t uturn = kFALSE;
+ Bool_t trackingFailed = kFALSE;
Bool_t tooManyStep = kFALSE;
while (TMath::Abs(residue) > fgkRungeKuttaMaxResidue && stepNumber <= fgkMaxStepNumber) {
}
stepNumber ++;
step = TMath::Abs(step);
- AliMUONTrackExtrap::ExtrapOneStepRungekutta(chargeExtrap,step,v3,v3New);
+ if (!AliMUONTrackExtrap::ExtrapOneStepRungekutta(chargeExtrap,step,v3,v3New)) {
+ trackingFailed = kTRUE;
+ break;
+ }
residue = zEnd - v3New[2];
step *= dZ/(v3New[2]-trackParam->GetZ());
} while (residue*dZ < 0 && TMath::Abs(residue) > fgkRungeKuttaMaxResidue);
- if (v3New[5]*v3[5] < 0) { // the track turned around
+ if (trackingFailed) break;
+ else if (v3New[5]*v3[5] < 0) { // the track turned around
cout<<"W-AliMUONTrackExtrap::ExtrapToZRungekutta: The track turned around"<<endl;
uturn = kTRUE;
break;
}
// terminate the extropolation with a straight line up to the exact "zEnd" value
- if (uturn) {
+ if (trackingFailed || uturn) {
// track ends +-100 meters away in the bending direction
dZ = zEnd - v3[2];
}
//__________________________________________________________________________
-void AliMUONTrackExtrap::ExtrapOneStepRungekutta(Double_t charge, Double_t step, Double_t* vect, Double_t* vout)
+Bool_t AliMUONTrackExtrap::ExtrapOneStepRungekutta(Double_t charge, Double_t step, Double_t* vect, Double_t* vout)
{
/// <pre>
/// ******************************************************************
vout[5] = cba*c;
rest = step - tl;
if (step < 0.) rest = -rest;
- if (rest < 1.e-5*TMath::Abs(step)) return;
+ if (rest < 1.e-5*TMath::Abs(step)) return kTRUE;
} while(1);
// angle too big, use helix
+ cout<<"W-AliMUONTrackExtrap::ExtrapOneStepRungekutta: Ruge-Kutta failed: switch to helix"<<endl;
f1 = f[0];
f2 = f[1];
f3 = f[2];
f4 = TMath::Sqrt(f1*f1+f2*f2+f3*f3);
+ if (f4 < 1.e-10) {
+ cout<<"E-AliMUONTrackExtrap::ExtrapOneStepRungekutta: magnetic field at (";
+ cout<<xyzt[0]<<", "<<xyzt[1]<<", "<<xyzt[2]<<") = "<<f4<<": giving up"<<endl;
+ return kFALSE;
+ }
rho = -f4*pinv;
tet = rho * step;
vout[kipy] = vect[kipy] + g4*vect[kipy] + g5*hxp[1] + g6*f2;
vout[kipz] = vect[kipz] + g4*vect[kipz] + g5*hxp[2] + g6*f3;
- return;
+ return kTRUE;
}