3 #include "FairRunAna.h" 
   12   double x[3] = {pos.X(), pos.Y(), pos.Z()};
 
   13   double B[3] = {0,0,0};
 
   14   FairRunAna::Instance()->GetField()->Field(x,B);
 
   15   return TVector3(B[0], B[1], B[2]);
 
   18 void PndGenfitField2::get(
const double& posX, 
const double& posY, 
const double& posZ, 
double& Bx, 
double& By, 
double& Bz)
 const {
 
   19   double x[3] = {posX, posY, posZ};
 
   20   double B[3] = {0,0,0};
 
   21   FairRunAna::Instance()->GetField()->Field(x,B);
 
TVector3 get(const TVector3 &pos) const 
return value at position 
PndGenfitField2()
define the field in this ctor (?)