JFIT::JMatrixNZ Class Reference

Determination of the co-variance matrix of hits for a track along z-axis (JFIT::JLine1Z). More...

#include <JMatrixNZ.hh>

Inheritance diagram for JFIT::JMatrixNZ:

Classes
struct	variance
	Auxiliary data structure for co-variance calculation. More...

Public Member Functions
	JMatrixNZ ()
	Default contructor.
template<class T >
	JMatrixNZ (const JVector3D &pos, T __begin, T __end, const double alpha, const double sigma)
	Constructor.
template<class T >
void	set (const JVector3D &pos, T __begin, T __end, const double alpha, const double sigma)
	Set co-variance matrix.

Static Private Member Functions
static double	getDot (const variance &first, const variance &second)
	Get dot product.

Private Attributes
std::vector< variance >	buffer

Detailed Description

Determination of the co-variance matrix of hits for a track along z-axis (JFIT::JLine1Z).

In this, the given angular and time resolution are taken into account.

Definition at line 28 of file JMatrixNZ.hh.

Constructor & Destructor Documentation

JMatrixNZ() [1/2]

JFIT::JMatrixNZ::JMatrixNZ ( )

inline

Default contructor.

Definition at line 39 of file JMatrixNZ.hh.

                :
      JMatrixNS()
    {}

JMatrixNZ() [2/2]

template<class T >

JFIT::JMatrixNZ::JMatrixNZ ( const JVector3D & pos, T __begin, T __end, const double alpha, const double sigma )

inline

Constructor.

The template argument T refers to an iterator of a data structure which should have the following member methods:

• double getX(); // [m]
• double getY(); // [m]
• double getZ(); // [m]

Parameters

pos	reference position [m]
__begin	begin of data
__end	end of data
alpha	angular resolution [deg]
sigma	time resolution [ns]

Definition at line 59 of file JMatrixNZ.hh.

                                      :
      JMatrixNS()
    {
      set(pos, __begin, __end, alpha, sigma);
    }

Member Function Documentation

set()

template<class T >

void JFIT::JMatrixNZ::set ( const JVector3D & pos, T __begin, T __end, const double alpha, const double sigma )

inline

Set co-variance matrix.

The template argument T refers to an iterator of a data structure which should have the following member methods:

• double getX(); // [m]
• double getY(); // [m]
• double getZ(); // [m]

Parameters

pos	reference position [m]
__begin	begin of data
__end	end of data
alpha	angular resolution [deg]
sigma	time resolution [ns]

Definition at line 85 of file JMatrixNZ.hh.

    {
      using namespace std;
      using namespace JPP;
 
 
      const int N = distance(__begin, __end);
 
      this ->resize(N);
      buffer.resize(N);
 
      const double ta = alpha * PI / 180.0;
      const double ct = cos(ta);
      const double st = sin(ta);
 
 
      // angular resolution
 
      for (T i = __begin; i != __end; ++i) {
        
        const double dx = i->getX() - pos.getX(); 
        const double dy = i->getY() - pos.getY(); 
        const double dz = i->getZ() - pos.getZ(); 
 
        const double R  = sqrt(dx*dx + dy*dy);
        
        double x  = ta * getKappaC() * getInverseSpeedOfLight();
        double y  = ta * getKappaC() * getInverseSpeedOfLight();
        double v  = ta * getInverseSpeedOfLight();
        double w  = ta * getInverseSpeedOfLight();
 
        if (R != 0.0) {
          x *= dx / R;
          y *= dy / R;
        }
 
        x *=  (dz*ct - dx*st);
        y *=  (dz*ct - dy*st);
        v *= -(dx*ct + dz*st);
        w *= -(dy*ct + dz*st);
        
        buffer[distance(__begin,i)] = variance(x, y, v, w);
      }
 
      for (int i = 0; i != N; ++i) {
 
        for (int j = 0; j != i; ++j) {
          (*this)(i, j) = getDot(buffer[i], buffer[j]);
          (*this)(j, i) = (*this)(i, j);
        }
 
        (*this)(i, i) = getDot(buffer[i], buffer[i]) +  sigma * sigma;
      }
    }

getDot()

static double JFIT::JMatrixNZ::getDot ( const variance & first, const variance & second )

inlinestaticprivate

Get dot product.

Parameters

first	first variance
second	second variance

Returns

dot product

Definition at line 196 of file JMatrixNZ.hh.

    {
      return (first.x * second.x  +
              first.y * second.y  +
              first.v * second.v  +
              first.w * second.w);
              
    }

Member Data Documentation

buffer

std::vector<variance> JFIT::JMatrixNZ::buffer

private

Definition at line 186 of file JMatrixNZ.hh.

---

The documentation for this class was generated from the following file:

• JMatrixNZ.hh