vgl_line_2d_regression< T > Class Template Reference

#include <vgl_line_2d_regression.h>

List of all members.

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Detailed Description

template<class T>
class vgl_line_2d_regression< T >

A class to hold the line 2d_regression data and actual fitting code.

In addition to fitting a line to a set of points (orthogonal regression), it is designed to help with incremental fitting. You can inexpensively add and remove points. This class does not store the points; it merely stores enough aggregate information to estimate the line parameters.

Definition at line 31 of file vgl_line_2d_regression.h.

Public Member Functions
	vgl_line_2d_regression ()
	Constructor.
	~vgl_line_2d_regression ()
unsigned int	get_n_pts () const
	The number of points added.
void	increment_partial_sums (const T x, const T y)
	Add a point to the 2d_regression.
void	decrement_partial_sums (const T x, const T y)
	Remove a point from the 2d_regression.
void	clear ()
	Clear 2d_regression sums.
double	get_rms_error (const T a, const T b, const T c)
	Get fitting error for a given line.
double	get_rms_error ()
	Get fitting error for current fitted line.
void	init_rms_error_est ()
	Initialize estimated fitting error.
double	get_rms_error_est (vgl_point_2d< T > const &p, bool increment=true)
	Get estimated fitting error if the point (x, y) were added to the fit.
vgl_line_2d< T >	get_line () const
	Get the fitted line.
bool	fit ()
	Fit a line to the current point set.
bool	fit_constrained (T x, T y)
	Fit a line to the current point set constrained to pass through (x,y).
Private Attributes
unsigned int	npts_
	number of points in the regression data
vgl_line_2d< T >	line_
	the fitted line
T	Sx_
T	Sy_
T	Sxx_
T	Sxy_
T	Syy_
	partial sums
double	squared_error_
	an estimate of the squared error

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Constructor & Destructor Documentation

template<class T> vgl_line_2d_regression< T >::vgl_line_2d_regression (   )

Constructor. Definition at line 17 of file vgl_line_2d_regression.txx.

template<class T> vgl_line_2d_regression< T >::~vgl_line_2d_regression (   )  [inline]

Definition at line 40 of file vgl_line_2d_regression.h.

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Member Function Documentation

template<class T> void vgl_line_2d_regression< T >::clear (   )

Clear 2d_regression sums. This will reset the object to the freshly constructed state of having zero points. Definition at line 49 of file vgl_line_2d_regression.txx.

template<class T> void vgl_line_2d_regression< T >::decrement_partial_sums (  const T  x, const T  y )

Remove a point from the 2d_regression. This should be a previously added point, although this cannot be verified. Definition at line 36 of file vgl_line_2d_regression.txx.

template<class T> bool vgl_line_2d_regression< T >::fit (   )

Fit a line to the current point set. Definition at line 62 of file vgl_line_2d_regression.txx.

template<class T> bool vgl_line_2d_regression< T >::fit_constrained (  T  x, T  y )

Fit a line to the current point set constrained to pass through (x,y). Definition at line 84 of file vgl_line_2d_regression.txx.

template<class T> vgl_line_2d<T> vgl_line_2d_regression< T >::get_line (   )  const [inline]

Get the fitted line. Definition at line 82 of file vgl_line_2d_regression.h.

template<class T> unsigned int vgl_line_2d_regression< T >::get_n_pts (   )  const [inline]

The number of points added. Definition at line 43 of file vgl_line_2d_regression.h.

template<class T> double vgl_line_2d_regression< T >::get_rms_error (   )

Get fitting error for current fitted line. Definition at line 115 of file vgl_line_2d_regression.txx.

template<class T> double vgl_line_2d_regression< T >::get_rms_error (  const T  a, const T  b, const T  c )

Get fitting error for a given line. Definition at line 104 of file vgl_line_2d_regression.txx.

template<class T> double vgl_line_2d_regression< T >::get_rms_error_est (  vgl_point_2d< T > const &  p, bool  increment = true )

Get estimated fitting error if the point (x, y) were added to the fit. You must call init_rms_error_est() to initialize the running totals before the first use of this function. If increment is true, the running totals are updated as if the point p was added to the point set. It does not update the point set, however, so the point will not affect subsequent line estimation. Definition at line 142 of file vgl_line_2d_regression.txx.

template<class T> void vgl_line_2d_regression< T >::increment_partial_sums (  const T  x, const T  y )

Add a point to the 2d_regression. Definition at line 24 of file vgl_line_2d_regression.txx.

template<class T> void vgl_line_2d_regression< T >::init_rms_error_est (   )

Initialize estimated fitting error. squared_error_ = squared_error_ + d^2 npts_+1 Initialize the recursive estimation of fitting error Definition at line 131 of file vgl_line_2d_regression.txx.

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Member Data Documentation

template<class T> vgl_line_2d<T> vgl_line_2d_regression< T >::line_ [private]

the fitted line Definition at line 35 of file vgl_line_2d_regression.h.

template<class T> unsigned int vgl_line_2d_regression< T >::npts_ [private]

number of points in the regression data Definition at line 34 of file vgl_line_2d_regression.h.

template<class T> double vgl_line_2d_regression< T >::squared_error_ [private]

an estimate of the squared error Definition at line 37 of file vgl_line_2d_regression.h.

template<class T> T vgl_line_2d_regression< T >::Sx_ [private]

Definition at line 36 of file vgl_line_2d_regression.h.

template<class T> T vgl_line_2d_regression< T >::Sxx_ [private]

Definition at line 36 of file vgl_line_2d_regression.h.

template<class T> T vgl_line_2d_regression< T >::Sxy_ [private]

Definition at line 36 of file vgl_line_2d_regression.h.

template<class T> T vgl_line_2d_regression< T >::Sy_ [private]

Definition at line 36 of file vgl_line_2d_regression.h.

template<class T> T vgl_line_2d_regression< T >::Syy_ [private]

partial sums Definition at line 36 of file vgl_line_2d_regression.h.

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

• core/vgl/algo/vgl_line_2d_regression.h
• core/vgl/algo/vgl_line_2d_regression.txx

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