This stores the non-zero projection matrix elements for every 'densel' that contributes to a given bin. More...

#include "stir/recon_buildblock/ProjMatrixElemsForOneBin.h"

Public Types
typedef ProjMatrixElemsForOneBinValue	value_type
	Recommended way to call the type of the elements, instead of referring to the actual classname.
typedef Element_vector::iterator	iterator
	typedefs for iterator support
typedef Element_vector::const_iterator	const_iterator
typedef Element_vector::reverse_iterator	reverse_iterator
typedef Element_vector::const_reverse_iterator	const_reverse_iterator
typedef Element_vector::size_type	size_type
typedef Element_vector::difference_type	difference_type
typedef std::random_access_iterator_tag	iterator_category
typedef value_type &	reference
typedef const value_type &	const_reference

Public Member Functions
	ProjMatrixElemsForOneBin (const Bin &bin=Bin(), const int default_capacity=0)
	constructor
Succeeded	check_state () const
	check if each voxel occurs only once
const Bin &	get_bin () const
	get the bin coordinates corresponding to this row
void	set_bin (const Bin &)
	and set the bin coordinates
iterator	begin ()
	functions for allowing iterator access
const_iterator	begin () const
iterator	end ()
const_iterator	end () const
reverse_iterator	rbegin ()
const_reverse_iterator	rbegin () const
reverse_iterator	rend ()
const_reverse_iterator	rend () const
void	erase ()
	reset lor to 0 length
iterator	erase (iterator it)
	remove a single value_type
void	push_back (const value_type &)
	add a new value_type object at the end
void	reserve (size_type max_number)
	reserve enough space for max_number elements (but don't fill them in)
size_type	size () const
	number of non-zero elements
size_type	capacity () const
	number of allocated elements
ProjMatrixElemsForOneBin &	operator*= (const float d)
	Multiplies all values with a constant.
ProjMatrixElemsForOneBin &	operator/= (const float d)
	Divides all values with a constant.
void	sort ()
	Sort the elements on coordinates of the voxels.
void	merge (ProjMatrixElemsForOneBin &lor)
	merge 2nd lor into current object
bool	operator== (const ProjMatrixElemsForOneBin &) const
	Compare 2 lors to see if they are equal.
bool	operator!= (const ProjMatrixElemsForOneBin &) const
	Compare 2 lors.
float	square_sum () const
	Return sum of squares of all values.
void	back_project (DiscretisedDensity< 3, float > &, const Bin &) const
	back project a single bin (accumulates)
void	forward_project (Bin &, const DiscretisedDensity< 3, float > &) const
	forward project into a single bin (accumulates)
void	back_project (DiscretisedDensity< 3, float > &, const RelatedBins &) const
	back project related bins (accumulates)
void	forward_project (RelatedBins &, const DiscretisedDensity< 3, float > &) const
	forward project related bins (accumulates)

Detailed Description

This stores the non-zero projection matrix elements for every 'densel' that contributes to a given bin.

In the usual terminology, this class implements a Line (or Tube) of Response (LOR, or TOR).

Todo: Most of the members of this class would work just as well for a (not yet existing) class ProjMatrixElemsForOneDensel. This means that we should derived both from a common base class, templated in the type of element.

Todo: It might be useful to template this class in terms of the element-type as well. That way, we could have 'compact' elements, efficient elements, etc. However, doing this will probably only be useful if all ProjMatrixByBin classes are then templated as well, which would be a pain.

Member Typedef Documentation

◆ value_type

typedef ProjMatrixElemsForOneBinValue stir::ProjMatrixElemsForOneBin::value_type

Recommended way to call the type of the elements, instead of referring to the actual classname.

Think about this name as 'the type of the value of a ProjMatrixElemsForOneBin::iterator *'.

This typedef is also required for 'standard' iterators.

Constructor & Destructor Documentation

◆ ProjMatrixElemsForOneBin()

stir::ProjMatrixElemsForOneBin::ProjMatrixElemsForOneBin	(	const Bin &	bin = Bin(),
		const int	default_capacity = 0 )

explicit

constructor

Parameters

bin	effectively calls set_bin(bin)
default_capacity	effectively calls reserve(default_capacity)

References ProjMatrixElemsForOneBin().

Referenced by back_project(), check_state(), forward_project(), merge(), operator!=(), operator==(), and ProjMatrixElemsForOneBin().

Member Function Documentation

◆ check_state()

Succeeded stir::ProjMatrixElemsForOneBin::check_state ( ) const

check if each voxel occurs only once

References begin(), stir::ProjMatrixElemsForOneBinValue::coordinates_equal(), ProjMatrixElemsForOneBin(), size(), sort(), and stir::warning().

Referenced by stir::ProjMatrixByBin::get_proj_matrix_elems_for_one_bin(), and merge().

◆ get_bin()

const Bin & stir::ProjMatrixElemsForOneBin::get_bin ( ) const

inline

get the bin coordinates corresponding to this row

References get_bin().

Referenced by stir::ProjMatrixByBin::cache_proj_matrix_elems_for_one_bin(), get_bin(), and stir::ProjMatrixByBin::get_cached_proj_matrix_elems_for_one_bin().

◆ set_bin()

void stir::ProjMatrixElemsForOneBin::set_bin ( const Bin & new_bin )

inline

and set the bin coordinates

References set_bin().

Referenced by stir::ProjMatrixByBin::get_proj_matrix_elems_for_one_bin(), and set_bin().

◆ begin()

ProjMatrixElemsForOneBin::iterator stir::ProjMatrixElemsForOneBin::begin ( )

inline

functions for allowing iterator access

References begin().

Referenced by stir::BackProjectorByBinUsingSquareProjMatrixByBin::actual_back_project(), back_project(), begin(), check_state(), forward_project(), merge(), operator*=(), operator/=(), operator==(), sort(), and square_sum().

◆ erase() [1/2]

void stir::ProjMatrixElemsForOneBin::erase ( )

reset lor to 0 length

Referenced by erase(), stir::ProjMatrixByBin::get_proj_matrix_elems_for_one_bin(), and merge().

◆ erase() [2/2]

ProjMatrixElemsForOneBin::iterator stir::ProjMatrixElemsForOneBin::erase ( iterator it )

inline

remove a single value_type

References erase().

◆ push_back()

void stir::ProjMatrixElemsForOneBin::push_back ( const value_type & el )

inline

add a new value_type object at the end

Warning: For future compatibility, it is required (but not checked) that the elements are added such that calling sort() after the push_back() would not change the order of the elements. Otherwise, schemes for 'incremental' storing of coordinates would require too much overhead.

References push_back().

Referenced by merge(), push_back(), and stir::RayTraceVoxelsOnCartesianGrid().

◆ reserve()

void stir::ProjMatrixElemsForOneBin::reserve ( size_type max_number )

reserve enough space for max_number elements (but don't fill them in)

Referenced by stir::RayTraceVoxelsOnCartesianGrid().

◆ size()

ProjMatrixElemsForOneBin::size_type stir::ProjMatrixElemsForOneBin::size ( ) const

inline

number of non-zero elements

References size().

Referenced by check_state(), merge(), stir::RayTraceVoxelsOnCartesianGrid(), and size().

◆ operator*=()

ProjMatrixElemsForOneBin & stir::ProjMatrixElemsForOneBin::operator*= ( const float d )

Multiplies all values with a constant.

References begin().

◆ operator/=()

ProjMatrixElemsForOneBin & stir::ProjMatrixElemsForOneBin::operator/= ( const float d )

Divides all values with a constant.

References begin().

◆ sort()

void stir::ProjMatrixElemsForOneBin::sort ( )

Sort the elements on coordinates of the voxels.

Uses value_type::coordinates_less as ordering function.

References begin(), and stir::ProjMatrixElemsForOneBinValue::coordinates_less().

Referenced by check_state(), merge(), and stir::RayTraceVoxelsOnCartesianGrid().

◆ merge()

void stir::ProjMatrixElemsForOneBin::merge ( ProjMatrixElemsForOneBin & lor )

merge 2nd lor into current object

This makes sure that in the result, no duplicate coordinates occur.

Warning: This currently modifies the argument lor.

References begin(), check_state(), stir::ProjMatrixElemsForOneBinValue::coordinates_equal(), stir::ProjMatrixElemsForOneBinValue::coordinates_less(), erase(), ProjMatrixElemsForOneBin(), push_back(), size(), and sort().

◆ operator==()

bool stir::ProjMatrixElemsForOneBin::operator== ( const ProjMatrixElemsForOneBin & lor ) const

Compare 2 lors to see if they are equal.

Warning: Compares element by element. Does not sort first or so.; Compares float values, so uses a tolerance. This tolerance is currently set to a fraction of the maximum value in the first lor.; this is a fairly CPU intensive operation.

References begin(), and ProjMatrixElemsForOneBin().

◆ operator!=()

bool stir::ProjMatrixElemsForOneBin::operator!= ( const ProjMatrixElemsForOneBin & lor ) const

Compare 2 lors.

References ProjMatrixElemsForOneBin().

◆ square_sum()

float stir::ProjMatrixElemsForOneBin::square_sum ( ) const

Return sum of squares of all values.

Warning: This sums over all elements in the LOR, irrespective if they are inside the FOV or not

References begin(), and stir::square().

◆ back_project() [1/2]

void stir::ProjMatrixElemsForOneBin::back_project	(	DiscretisedDensity< 3, float > &	density,
		const Bin &	single ) const

back project a single bin (accumulates)

References begin(), stir::Bin::get_bin_value(), stir::VectorWithOffset< T >::get_max_index(), and stir::VectorWithOffset< T >::get_min_index().

Referenced by stir::BackProjectorByBinUsingProjMatrixByBin::actual_back_project(), stir::BackProjectorByBinUsingSquareProjMatrixByBin::actual_back_project(), and back_project().

◆ forward_project() [1/2]

void stir::ProjMatrixElemsForOneBin::forward_project	(	Bin &	single,
		const DiscretisedDensity< 3, float > &	density ) const

forward project into a single bin (accumulates)

References begin(), stir::VectorWithOffset< T >::get_max_index(), and stir::VectorWithOffset< T >::get_min_index().

Referenced by forward_project().

◆ back_project() [2/2]

void stir::ProjMatrixElemsForOneBin::back_project	(	DiscretisedDensity< 3, float > &	density,
		const RelatedBins &	r_bins ) const

back project related bins (accumulates)

References back_project(), stir::RelatedBins::begin(), stir::RelatedBins::end(), stir::DataSymmetriesForBins::find_symmetry_operation_from_basic_bin(), stir::Bin::get_bin_value(), stir::RelatedBins::get_symmetries_ptr(), and ProjMatrixElemsForOneBin().

◆ forward_project() [2/2]

void stir::ProjMatrixElemsForOneBin::forward_project	(	RelatedBins &	r_bins,
		const DiscretisedDensity< 3, float > &	density ) const

forward project related bins (accumulates)

References stir::RelatedBins::begin(), stir::RelatedBins::end(), stir::DataSymmetriesForBins::find_symmetry_operation_from_basic_bin(), forward_project(), stir::RelatedBins::get_symmetries_ptr(), and ProjMatrixElemsForOneBin().

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

/home/kris/devel/STIRdistrib/STIR/src/include/stir/recon_buildblock/ProjMatrixElemsForOneBin.h
/home/kris/devel/STIRdistrib/STIR/src/include/stir/recon_buildblock/ProjMatrixElemsForOneBin.inl
/home/kris/devel/STIRdistrib/STIR/src/recon_buildblock/ProjMatrixElemsForOneBin.cxx

Public Types

Public Member Functions

Detailed Description

Member Typedef Documentation

◆ value_type

Constructor & Destructor Documentation

◆ ProjMatrixElemsForOneBin()

Member Function Documentation

◆ check_state()

◆ get_bin()

◆ set_bin()

◆ begin()

◆ erase() [1/2]

◆ erase() [2/2]

◆ push_back()

◆ reserve()

◆ size()

◆ operator*=()

◆ operator/=()

◆ sort()

◆ merge()

◆ operator==()

◆ operator!=()

◆ square_sum()

◆ back_project() [1/2]

◆ forward_project() [1/2]

◆ back_project() [2/2]

◆ forward_project() [2/2]