JGEOMETRY2D::JEigenValues2D Class Reference

Eigen values in 2D. More...

#include <JEigenValues2D.hh>

Inheritance diagram for JGEOMETRY2D::JEigenValues2D:

Public Member Functions
template<class T >
	JEigenValues2D (T __begin, T __end)
	Constructor. More...
int	getN () const
	Get number of eigen values. More...
int	getN (double precision) const
	Get number of eigen values with minimal value. More...
double	getX () const
	Get x position. More...
double	getY () const
	Get y position. More...
JVector2D &	negate ()
	Negate vector. More...
JVector2D &	add (const JVector2D &vector)
	Add vector. More...
JVector2D &	sub (const JVector2D &vector)
	Subtract vector. More...
JVector2D &	mul (const double factor)
	Scale vector. More...
JVector2D &	mul (const JNullType &object)
	Multiply with object. More...
JVector2D &	div (const double factor)
	Scale vector. More...
JVector2D &	transform (const JMatrix2D &T)
	Transform. More...
bool	equals (const JVector2D &vector) const
	Check equality. More...
double	getLengthSquared () const
	Get length squared. More...
double	getLength () const
	Get length. More...
double	getDistanceSquared (const JVector2D &point) const
	Get squared of distance to point. More...
double	getDistance (const JVector2D &point) const
	Get distance to point. More...
double	getDot (const JVector2D &point) const
	Get dot product. More...
double	getPerpDot (const JVector2D &point) const
	Get perpendicular dot product. More...

Protected Attributes
int	N
double	__x
double	__y

Detailed Description

Eigen values in 2D.

Definition at line 24 of file JEigenValues2D.hh.

Constructor & Destructor Documentation

template<class T >

JGEOMETRY2D::JEigenValues2D::JEigenValues2D ( T  __begin, T  __end  )

inline

Constructor.

Parameters

__begin	begin of data
__end	end of data

Definition at line 35 of file JEigenValues2D.hh.

                            :
      JVector2D(),
      N(0)
    {
      const JCenter2D center(__begin, __end);
        
      // RMS matrix
        
      TMatrixDSym A(2);
        
      for (int i = 0; i != 2; ++i) {
        for (int j = 0; j != 2; ++j) {
          A(i,j) = 0.0;
        }
      }
        
      for (T i = __begin; i != __end; ++i) {
        
        const double dx = center.getX() - i->getX();
        const double dy = center.getY() - i->getY();
          
        A(0,0) += (dx * dx);
        A(0,1) += (dx * dy);
        
        A(1,1) += (dy * dy);
      }
      
      A(1,0) = A(0,1);

      const TVectorD V = TMatrixDSymEigen(A).GetEigenValues();   // copy!

      N = V.GetNoElements();

      switch (N) {

      case 2:
        __y = V[1];

      case 1:
        __x = V[0];
        break;

      default:
        break;
      }
    }

Member Function Documentation

int JGEOMETRY2D::JEigenValues2D::getN ( ) const

inline

Get number of eigen values.

Returns

number of eigen values

Definition at line 89 of file JEigenValues2D.hh.

    {
      return N;
    }

int JGEOMETRY2D::JEigenValues2D::getN ( double  precision ) const

inline

Get number of eigen values with minimal value.

Parameters

precision

minimal value

Returns

number of eigen values

Definition at line 101 of file JEigenValues2D.hh.

    {
      int n = 0;

      if (fabs(getX()) >= precision) ++n;
      if (fabs(getY()) >= precision) ++n;

      if (n > N)
        return N;
      else
        return n;
    }

double JGEOMETRY2D::JVector2D::getX ( ) const

inlineinherited

Get x position.

Returns

x position

Definition at line 61 of file JVector2D.hh.

    { 
      return __x;
    }

double JGEOMETRY2D::JVector2D::getY ( ) const

inlineinherited

Get y position.

Returns

y position

Definition at line 72 of file JVector2D.hh.

    { 
      return __y;
    }

JVector2D& JGEOMETRY2D::JVector2D::negate ( )

inlineinherited

Negate vector.

Returns

this vector

Definition at line 83 of file JVector2D.hh.

    {
      __x = -__x;
      __y = -__y;

      return *this;
    }

JVector2D& JGEOMETRY2D::JVector2D::add ( const JVector2D &  vector )

inlineinherited

Add vector.

Parameters

vector

vector

Returns

this vector

Definition at line 98 of file JVector2D.hh.

    {
      __x += vector.getX();
      __y += vector.getY();

      return *this;
    }

JVector2D& JGEOMETRY2D::JVector2D::sub ( const JVector2D &  vector )

inlineinherited

Subtract vector.

Parameters

vector

vector

Returns

this vector

Definition at line 113 of file JVector2D.hh.

    {
      __x -= vector.getX();
      __y -= vector.getY();

      return *this;
    }

JVector2D& JGEOMETRY2D::JVector2D::mul ( const double  factor )

inlineinherited

Scale vector.

Parameters

factor

multiplication factor

Returns

this vector

Definition at line 128 of file JVector2D.hh.

    {
      __x *= factor;
      __y *= factor;

      return *this;
    }

JVector2D & JMATH::JMath< JVector2D , JNullType >::mul ( const JNullType &  object )

inlineinherited

Multiply with object.

Parameters

object

object

Returns

result object

Definition at line 273 of file JMath.hh.

    {
      return static_cast<JFirst_t&>(*this) = JCalculator<JFirst_t>::calculator.mul(static_cast<const JFirst_t&>(*this), object);
    }

JVector2D& JGEOMETRY2D::JVector2D::div ( const double  factor )

inlineinherited

Scale vector.

Parameters

factor

division factor

Returns

this vector

Definition at line 143 of file JVector2D.hh.

    {
      __x /= factor;
      __y /= factor;

      return *this;
    }

JVector2D& JGEOMETRY2D::JVector2D::transform ( const JMatrix2D &  T )

inlineinherited

Transform.

Parameters

T

matrix

Returns

this vector

Definition at line 158 of file JVector2D.hh.

    {
      T.transform(__x, __y);

      return *this;
    }

bool JGEOMETRY2D::JVector2D::equals ( const JVector2D &  vector ) const

inlineinherited

Check equality.

Parameters

vector

vector

Returns

true if vectors are equal; else false

Definition at line 172 of file JVector2D.hh.

    {
      return (getX() == vector.getX() && 
              getY() == vector.getY());
    }

double JGEOMETRY2D::JVector2D::getLengthSquared ( ) const

inlineinherited

Get length squared.

Returns

square of length

Definition at line 184 of file JVector2D.hh.

    { 
      return getX()*getX() + getY()*getY();
    }

double JGEOMETRY2D::JVector2D::getLength ( ) const

inlineinherited

Get length.

Returns

length

Definition at line 195 of file JVector2D.hh.

    { 
      return sqrt(getLengthSquared());
    }

double JGEOMETRY2D::JVector2D::getDistanceSquared ( const JVector2D &  point ) const

inlineinherited

Get squared of distance to point.

Parameters

point

point

Returns

square of distance

Definition at line 207 of file JVector2D.hh.

    {
      return JVector2D(point).sub(*this).getLengthSquared();
    }

double JGEOMETRY2D::JVector2D::getDistance ( const JVector2D &  point ) const

inlineinherited

Get distance to point.

Parameters

point

point

Returns

distance

Definition at line 219 of file JVector2D.hh.

    {
      return sqrt(getDistanceSquared(point));
    }

double JGEOMETRY2D::JVector2D::getDot ( const JVector2D &  point ) const

inlineinherited

Get dot product.

Parameters

point

vector

Returns

dot product

Definition at line 231 of file JVector2D.hh.

    {
      return
        getX() * point.getX() + 
        getY() * point.getY();
    }

double JGEOMETRY2D::JVector2D::getPerpDot ( const JVector2D &  point ) const

inlineinherited

Get perpendicular dot product.

Parameters

point

vector

Returns

perpendicular dot product

Definition at line 245 of file JVector2D.hh.

    {
      return
        getX() * point.getY() - 
        getY() * point.getX();
    }

Member Data Documentation

int JGEOMETRY2D::JEigenValues2D::N

protected

Definition at line 116 of file JEigenValues2D.hh.

double JGEOMETRY2D::JVector2D::__x

protectedinherited

Definition at line 253 of file JVector2D.hh.

double JGEOMETRY2D::JVector2D::__y

protectedinherited

Definition at line 254 of file JVector2D.hh.

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

• JEigenValues2D.hh