G4LineCurrentMagField.cc

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// $Id$
// -------------------------------------------------------------------
 
#include "G4LineCurrentMagField.hh"
#include "globals.hh"
 
G4LineCurrentMagField::G4LineCurrentMagField(G4double pFieldConstant)
{
   fFieldConstant = pFieldConstant ;
}
////////////////////////////////////////////////////////////////////////
 
G4LineCurrentMagField::~G4LineCurrentMagField()
{
}
 
///////////////////////////////////////////////////////////////////////////
 
 
void G4LineCurrentMagField::GetFieldValue( const G4double yTrack[7],
                                                 G4double B[3]      ) const  
{
   //   G4double fFieldConstant = 100 ;
   G4double a = 1.00 ;   // mm
   G4double x = a*yTrack[0], y = a*yTrack[1] ;
   G4double x2 = x*x, y2 = y*y, r2 = x2 + y2 ;
   G4double r = std::sqrt(r2+a*a) ;
   G4double Br = fFieldConstant/r;
   B[0] = -Br*y/r ;
   B[1] = Br*x/r ;
   B[2] = 0 ;
}
 
// -----------------------------------------------------------------