Detailed Description

template<class T>
class mrpt::math::CMatrixTemplate< T >

This template class provides the basic functionality for a general 2D any-size, resizable container of numerical or non-numerical elements.

NOTES:

This class is not serializable since it is a template. For using serialization, see mrpt::math::CMatrixNumeric
First row or column index is "0".
This class includes range checks with ASSERT_() if compiling with "_DEBUG" or "MRPT_ALWAYS_CHECKS_DEBUG_MATRICES=1".
Please DO NOT use as template class type any other class. It can be safely used the following types:
- Elemental types (int,char,float,doble,...)
- Data struct (Not classes!)
- Any kind of pointers (user is responsible for allocating and freeing the memory addressed by pointers).

Note: Memory blocks for each row are 16-bytes aligned (since MRPT 0.7.0).; For a complete introduction to Matrices and vectors in MRPT, see: http://www.mrpt.org/Matrices_vectors_arrays_and_Linear_Algebra_MRPT_and_Eigen_classes

See also: CMatrixTemplateNumeric

Definition at line 72 of file CMatrixTemplate.h.

#include <mrpt/math/CMatrixTemplate.h>

Inheritance diagram for mrpt::math::CMatrixTemplate< T >:

Public Types
using	value_type = T
	The type of the matrix elements. More...

using	reference = T &

using	const_reference = const T &

using	size_type = std::size_t

using	difference_type = std::ptrdiff_t

Public Member Functions
template<size_t N>
void	ASSERT_ENOUGHROOM (size_t r, size_t c) const
	Checks whether the rows [r-N,r+N] and the columns [c-N,c+N] are present in the matrix. More...

void	fillAll (const T &val)

void	swap (CMatrixTemplate< T > &o)
	Swap with another matrix very efficiently (just swaps a pointer and two integer values). More...

	CMatrixTemplate (const CMatrixTemplate &m)
	Constructors. More...

	CMatrixTemplate (size_t row=1, size_t col=1)

	CMatrixTemplate (const CMatrixTemplate &m, const size_t cropRowCount, const size_t cropColCount)
	Copy constructor & crop from another matrix. More...

template<typename V , size_t N>
	CMatrixTemplate (size_t row, size_t col, V(&theArray)[N])
	Constructor from a given size and a C array. More...

template<typename V >
	CMatrixTemplate (size_t row, size_t col, const V &theVector)
	Constructor from a given size and a STL container (std::vector, std::list,...) with the initial values. More...

virtual	~CMatrixTemplate ()
	Destructor. More...

CMatrixTemplate &	operator= (const CMatrixTemplate &m)
	Assignment operator from another matrix. More...

template<typename V , size_t N>
CMatrixTemplate &	operator= (V(&theArray)[N])
	Assignment operator for initializing from a C array (The matrix must be set to the correct size before invoking this asignament) More...

size_t	rows () const
	Number of rows in the matrix. More...

size_t	cols () const
	Number of columns in the matrix. More...

CMatrixTemplateSize	size () const
	Get a 2-vector with [NROWS NCOLS] (as in MATLAB command size(x)) More...

void	setSize (size_t row, size_t col, bool zeroNewElements=false)
	Changes the size of matrix, maintaining the previous contents. More...

void	resize (const CMatrixTemplateSize &siz, bool zeroNewElements=false)
	This method just checks has no effects in this class, but raises an exception if the expected size does not match. More...

T &	operator() (size_t row, size_t col)
	Subscript operator to get/set individual elements. More...

const T &	operator() (size_t row, size_t col) const
	Subscript operator to get individual elements. More...

T &	operator() (size_t ith)
	Subscript operator to get/set an individual element from a row or column matrix. More...

T	operator() (size_t ith) const
	Subscript operator to get/set an individual element from a row or column matrix. More...

void	set_unsafe (size_t row, size_t col, const T &v)
	Fast but unsafe method to write a value in the matrix. More...

const T &	get_unsafe (size_t row, size_t col) const
	Fast but unsafe method to read a value from the matrix. More...

T &	get_unsafe (size_t row, size_t col)
	Fast but unsafe method to get a reference from the matrix. More...

T *	get_unsafe_row (size_t row)
	Fast but unsafe method to obtain a pointer to a given row of the matrix (Use only in time critical applications) More...

const T *	get_unsafe_row (size_t row) const
	Fast but unsafe method to obtain a pointer to a given row of the matrix (Use only in critical applications) More...

CMatrixTemplate< T >	operator() (const size_t row1, const size_t row2, const size_t col1, const size_t col2) const
	Subscript operator to get a submatrix. More...

void	extractSubmatrix (const size_t row1, const size_t row2, const size_t col1, const size_t col2, CMatrixTemplate< T > &out) const
	Get a submatrix, given its bounds. More...

template<class EIGEN_MATRIX >
void	extractSubmatrix (const size_t row1, const size_t row2, const size_t col1, const size_t col2, EIGEN_MATRIX &out) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. More...

void	extractRows (size_t firstRow, size_t lastRow, CMatrixTemplate< T > &out) const
	Gets a series of contiguous rows. More...

void	extractColumns (size_t firstCol, size_t lastCol, CMatrixTemplate< T > &out) const
	Gets a series of contiguous columns. More...

void	extractCol (size_t nCol, std::vector< T > &out, int startingRow=0) const
	Returns a given column to a vector (without modifying the matrix) More...

void	extractCol (size_t nCol, CMatrixTemplate< T > &out, int startingRow=0) const
	Gets a given column to a vector (without modifying the matrix) More...

void	appendRow (const std::vector< T > &in)
	Appends a new row to the MxN matrix from a 1xN vector. More...

void	appendCol (const std::vector< T > &in)
	Appends a new column to the matrix from a vector. More...

void	insertCol (size_t nCol, const std::vector< T > &in)
	Inserts a column from a vector, replacing the current contents of that column. More...

void	getAsVector (std::vector< T > &out) const
	Returns a vector containing the matrix's values. More...

Protected Member Functions
void	realloc (size_t row, size_t col, bool newElementsToZero=false)
	Internal use only: It reallocs the memory for the 2D matrix, maintaining the previous contents if posible. More...

Protected Attributes
T **	m_Val

size_t	m_Rows

size_t	m_Cols

Member Typedef Documentation

◆ const_reference

template<class T >

using mrpt::math::CMatrixTemplate< T >::const_reference = const T&

Definition at line 79 of file CMatrixTemplate.h.

◆ difference_type

template<class T >

using mrpt::math::CMatrixTemplate< T >::difference_type = std::ptrdiff_t

Definition at line 81 of file CMatrixTemplate.h.

◆ reference

template<class T >

using mrpt::math::CMatrixTemplate< T >::reference = T&

Definition at line 78 of file CMatrixTemplate.h.

◆ size_type

template<class T >

using mrpt::math::CMatrixTemplate< T >::size_type = std::size_t

Definition at line 80 of file CMatrixTemplate.h.

◆ value_type

template<class T >

using mrpt::math::CMatrixTemplate< T >::value_type = T

The type of the matrix elements.

Definition at line 77 of file CMatrixTemplate.h.

Constructor & Destructor Documentation

◆ CMatrixTemplate() [1/5]

template<class T >

mrpt::math::CMatrixTemplate< T >::CMatrixTemplate ( const CMatrixTemplate< T > & m )

inline

Constructors.

Definition at line 174 of file CMatrixTemplate.h.

◆ CMatrixTemplate() [2/5]

template<class T >

mrpt::math::CMatrixTemplate< T >::CMatrixTemplate	(	size_t	row = `1`,
		size_t	col = `1`
	)

inline

Definition at line 180 of file CMatrixTemplate.h.

◆ CMatrixTemplate() [3/5]

template<class T >

mrpt::math::CMatrixTemplate< T >::CMatrixTemplate	(	const CMatrixTemplate< T > &	m,
		const size_t	cropRowCount,
		const size_t	cropColCount
	)

inline

Copy constructor & crop from another matrix.

Definition at line 188 of file CMatrixTemplate.h.

◆ CMatrixTemplate() [4/5]

template<class T >

template<typename V , size_t N>

mrpt::math::CMatrixTemplate< T >::CMatrixTemplate	(	size_t	row,
		size_t	col,
		V(&)	theArray[N]
	)

inline

Constructor from a given size and a C array.

The array length must match cols x row.

const double numbers[] = {
  1,2,3,
  4,5,6 };
       CMatrixDouble   M(3,2, numbers);

Definition at line 210 of file CMatrixTemplate.h.

◆ CMatrixTemplate() [5/5]

template<class T >

template<typename V >

mrpt::math::CMatrixTemplate< T >::CMatrixTemplate	(	size_t	row,
		size_t	col,
		const V &	theVector
	)

inline

Constructor from a given size and a STL container (std::vector, std::list,...) with the initial values.

The vector length must match cols x row.

Definition at line 234 of file CMatrixTemplate.h.

◆ ~CMatrixTemplate()

template<class T >

virtual mrpt::math::CMatrixTemplate< T >::~CMatrixTemplate ( )

inlinevirtual

Destructor.

Definition at line 254 of file CMatrixTemplate.h.

Member Function Documentation

◆ appendCol()

template<class T >

void mrpt::math::CMatrixTemplate< T >::appendCol ( const std::vector< T > & in )

inline

Appends a new column to the matrix from a vector.

The length of the vector must match the number of rows of the matrix, unless it is (0,0).

Exceptions

std::exception On size mismatch.

See also: extractCol; appendRow

Definition at line 649 of file CMatrixTemplate.h.

Referenced by mrpt::opengl::CGeneralizedCylinder::getClosedSection().

◆ appendRow()

template<class T >

void mrpt::math::CMatrixTemplate< T >::appendRow ( const std::vector< T > & in )

inline

Appends a new row to the MxN matrix from a 1xN vector.

The lenght of the vector must match the width of the matrix, unless it's empty: in that case the matrix is resized to 1xN.

CMatrixDouble  M(0,0);
CVectorDouble  v(7),w(7);
// ...
M.appendRow(v);
M.appendRow(w);

Exceptions

std::exception On incorrect vector length.

See also: extractRow; appendCol

Definition at line 620 of file CMatrixTemplate.h.

◆ ASSERT_ENOUGHROOM()

template<class T >

template<size_t N>

void mrpt::math::CMatrixTemplate< T >::ASSERT_ENOUGHROOM	(	size_t	r,
		size_t	c
	)		const

inline

Checks whether the rows [r-N,r+N] and the columns [c-N,c+N] are present in the matrix.

Definition at line 150 of file CMatrixTemplate.h.

◆ cols()

template<class T >

size_t mrpt::math::CMatrixTemplate< T >::cols ( ) const

inline

Number of columns in the matrix.

See also: rows(), getColCount, nr, nc

Definition at line 302 of file CMatrixTemplate.h.

Referenced by mrpt::math::CMatrixTemplate< mrpt::math::TPoint3D >::ASSERT_ENOUGHROOM(), mrpt::detectors::CFaceDetection::checkIfFaceRegions(), mrpt::vision::generateMask(), mrpt::opengl::CGeneralizedCylinder::getClosedSection(), and mrpt::math::CMatrixTemplateObjects< T >::operator=().

◆ extractCol() [1/2]

template<class T >

void mrpt::math::CMatrixTemplate< T >::extractCol	(	size_t	nCol,
		CMatrixTemplate< T > &	out,
		int	startingRow = `0`
	)		const

inline

Gets a given column to a vector (without modifying the matrix)

Exceptions

std::exception On index out of bounds

Definition at line 591 of file CMatrixTemplate.h.

◆ extractCol() [2/2]

template<class T >

void mrpt::math::CMatrixTemplate< T >::extractCol	(	size_t	nCol,
		std::vector< T > &	out,
		int	startingRow = `0`
	)		const

inline

Returns a given column to a vector (without modifying the matrix)

Exceptions

std::exception On index out of bounds

Definition at line 574 of file CMatrixTemplate.h.

Referenced by mrpt::opengl::CGeneralizedCylinder::getClosedSection().

◆ extractColumns()

template<class T >

void mrpt::math::CMatrixTemplate< T >::extractColumns	(	size_t	firstCol,
		size_t	lastCol,
		CMatrixTemplate< T > &	out
	)		const

inline

Gets a series of contiguous columns.

Exceptions

std::logic_error On index out of bounds

See also: extractColumn; extractRows

Definition at line 564 of file CMatrixTemplate.h.

◆ extractRows()

template<class T >

void mrpt::math::CMatrixTemplate< T >::extractRows	(	size_t	firstRow,
		size_t	lastRow,
		CMatrixTemplate< T > &	out
	)		const

inline

Gets a series of contiguous rows.

Exceptions

std::logic_error On index out of bounds

See also: extractRow; extractColumns

Definition at line 552 of file CMatrixTemplate.h.

◆ extractSubmatrix() [1/2]

template<class T >

void mrpt::math::CMatrixTemplate< T >::extractSubmatrix	(	const size_t	row1,
		const size_t	row2,
		const size_t	col1,
		const size_t	col2,
		CMatrixTemplate< T > &	out
	)		const

inline

Get a submatrix, given its bounds.

See also: extractSubmatrixSymmetricalBlocks

Definition at line 508 of file CMatrixTemplate.h.

Referenced by mrpt::math::CMatrixTemplate< mrpt::math::TPoint3D >::operator()().

◆ extractSubmatrix() [2/2]

template<class T >

template<class EIGEN_MATRIX >

void mrpt::math::CMatrixTemplate< T >::extractSubmatrix	(	const size_t	row1,
		const size_t	row2,
		const size_t	col1,
		const size_t	col2,
		EIGEN_MATRIX &	out
	)		const

inline

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Definition at line 528 of file CMatrixTemplate.h.

◆ fillAll()

template<class T >

void mrpt::math::CMatrixTemplate< T >::fillAll ( const T & val )

inline

Fill all the elements with a given value (Note: named "fillAll" since "fill" will be used by child classes)

Definition at line 158 of file CMatrixTemplate.h.

Referenced by mrpt::vision::CFeatureExtraction::extractFeaturesFAST(), mrpt::vision::CFeatureExtraction::extractFeaturesFASTER_N(), mrpt::vision::CFeatureExtraction::extractFeaturesORB(), and mrpt::vision::detail::trackFeatures_addNewFeats_simple_list().

◆ get_unsafe() [1/2]

template<class T >

T& mrpt::math::CMatrixTemplate< T >::get_unsafe	(	size_t	row,
		size_t	col
	)

inline

Fast but unsafe method to get a reference from the matrix.

Definition at line 458 of file CMatrixTemplate.h.

◆ get_unsafe() [2/2]

template<class T >

const T& mrpt::math::CMatrixTemplate< T >::get_unsafe	(	size_t	row,
		size_t	col
	)		const

inline

Fast but unsafe method to read a value from the matrix.

Definition at line 441 of file CMatrixTemplate.h.

Referenced by mrpt::detectors::CFaceDetection::checkIfDiagonalSurface(), mrpt::detectors::CFaceDetection::checkIfDiagonalSurface2(), mrpt::detectors::CFaceDetection::checkIfFacePlaneCov(), mrpt::detectors::CFaceDetection::checkIfFaceRegions(), mrpt::detectors::CFaceDetection::experimental_calcHist(), mrpt::detectors::CFaceDetection::experimental_segmentFace(), and mrpt::vision::detail::trackFeatures_addNewFeats_simple_list().

◆ get_unsafe_row() [1/2]

template<class T >

T* mrpt::math::CMatrixTemplate< T >::get_unsafe_row ( size_t row )

inline

Fast but unsafe method to obtain a pointer to a given row of the matrix (Use only in time critical applications)

Definition at line 476 of file CMatrixTemplate.h.

◆ get_unsafe_row() [2/2]

template<class T >

const T* mrpt::math::CMatrixTemplate< T >::get_unsafe_row ( size_t row ) const

inline

Fast but unsafe method to obtain a pointer to a given row of the matrix (Use only in critical applications)

Definition at line 493 of file CMatrixTemplate.h.

◆ getAsVector()

template<class T >

void mrpt::math::CMatrixTemplate< T >::getAsVector ( std::vector< T > & out ) const

inline

Returns a vector containing the matrix's values.

Definition at line 682 of file CMatrixTemplate.h.

Referenced by mrpt::opengl::CGeneralizedCylinder::getClosedSection().

◆ insertCol()

template<class T >

void mrpt::math::CMatrixTemplate< T >::insertCol	(	size_t	nCol,
		const std::vector< T > &	in
	)

inline

Inserts a column from a vector, replacing the current contents of that column.

Exceptions

std::exception On index out of bounds

See also: extractCol

Definition at line 669 of file CMatrixTemplate.h.

◆ operator()() [1/5]

template<class T >

CMatrixTemplate<T> mrpt::math::CMatrixTemplate< T >::operator()	(	const size_t	row1,
		const size_t	row2,
		const size_t	col1,
		const size_t	col2
	)		const

inline

Subscript operator to get a submatrix.

Definition at line 496 of file CMatrixTemplate.h.

◆ operator()() [2/5]

template<class T >

T& mrpt::math::CMatrixTemplate< T >::operator() ( size_t ith )

inline

Subscript operator to get/set an individual element from a row or column matrix.

Exceptions

std::exception If the object is not a column or row matrix.

Definition at line 364 of file CMatrixTemplate.h.

◆ operator()() [3/5]

template<class T >

T mrpt::math::CMatrixTemplate< T >::operator() ( size_t ith ) const

inline

Subscript operator to get/set an individual element from a row or column matrix.

Exceptions

std::exception If the object is not a column or row matrix.

Definition at line 395 of file CMatrixTemplate.h.

◆ operator()() [4/5]

template<class T >

T& mrpt::math::CMatrixTemplate< T >::operator()	(	size_t	row,
		size_t	col
	)

inline

Subscript operator to get/set individual elements.

Definition at line 328 of file CMatrixTemplate.h.

◆ operator()() [5/5]

template<class T >

const T& mrpt::math::CMatrixTemplate< T >::operator()	(	size_t	row,
		size_t	col
	)		const

inline

Subscript operator to get individual elements.

Definition at line 345 of file CMatrixTemplate.h.

◆ operator=() [1/2]

template<class T >

CMatrixTemplate& mrpt::math::CMatrixTemplate< T >::operator= ( const CMatrixTemplate< T > & m )

inline

Assignment operator from another matrix.

Definition at line 256 of file CMatrixTemplate.h.

Referenced by mrpt::math::CMatrixBool::operator=().

◆ operator=() [2/2]

template<class T >

template<typename V , size_t N>

CMatrixTemplate& mrpt::math::CMatrixTemplate< T >::operator= ( V(&) theArray[N] )

inline

Assignment operator for initializing from a C array (The matrix must be set to the correct size before invoking this asignament)

       CMatrixDouble   M(3,2);
const double numbers[] = {
  1,2,3,
  4,5,6 };
M = numbers;

Refer also to the constructor with initialization data CMatrixTemplate::CMatrixTemplate

Definition at line 277 of file CMatrixTemplate.h.

◆ realloc()

template<class T >

void mrpt::math::CMatrixTemplate< T >::realloc	(	size_t	row,
		size_t	col,
		bool	newElementsToZero = `false`
	)

inlineprotected

Internal use only: It reallocs the memory for the 2D matrix, maintaining the previous contents if posible.

Definition at line 90 of file CMatrixTemplate.h.

◆ resize()

template<class T >

void mrpt::math::CMatrixTemplate< T >::resize	(	const CMatrixTemplateSize &	siz,
		bool	zeroNewElements = `false`
	)

inline

This method just checks has no effects in this class, but raises an exception if the expected size does not match.

Definition at line 320 of file CMatrixTemplate.h.

◆ rows()

template<class T >

size_t mrpt::math::CMatrixTemplate< T >::rows ( ) const

inline

Number of rows in the matrix.

See also: rows(), getColCount, nr, nc

Definition at line 298 of file CMatrixTemplate.h.

Referenced by mrpt::math::CMatrixTemplate< mrpt::math::TPoint3D >::ASSERT_ENOUGHROOM(), mrpt::detectors::CFaceDetection::checkIfFaceRegions(), mrpt::vision::generateMask(), mrpt::opengl::CGeneralizedCylinder::getClosedSection(), and mrpt::math::CMatrixTemplateObjects< T >::operator=().

◆ set_unsafe()

template<class T >

void mrpt::math::CMatrixTemplate< T >::set_unsafe	(	size_t	row,
		size_t	col,
		const T &	v
	)

inline

Fast but unsafe method to write a value in the matrix.

Definition at line 424 of file CMatrixTemplate.h.

Referenced by mrpt::detectors::CFaceDetection::checkIfDiagonalSurface(), mrpt::detectors::CFaceDetection::experimental_calcHist(), mrpt::detectors::CFaceDetection::experimental_segmentFace(), mrpt::vision::CFeatureExtraction::extractFeaturesFAST(), mrpt::vision::CFeatureExtraction::extractFeaturesFASTER_N(), mrpt::vision::CFeatureExtraction::extractFeaturesORB(), and mrpt::vision::generateMask().

◆ setSize()

template<class T >

void mrpt::math::CMatrixTemplate< T >::setSize	(	size_t	row,
		size_t	col,
		bool	zeroNewElements = `false`
	)

inline

Changes the size of matrix, maintaining the previous contents.

Definition at line 313 of file CMatrixTemplate.h.

Referenced by mrpt::detectors::CFaceDetection::checkIfDiagonalSurface(), mrpt::detectors::CFaceDetection::checkIfFaceRegions(), mrpt::slam::TDataAssociationResults::clear(), mrpt::detectors::CFaceDetection::experimental_segmentFace(), mrpt::math::CMatrixTemplate< mrpt::math::TPoint3D >::extractCol(), mrpt::math::CMatrixTemplate< mrpt::math::TPoint3D >::extractColumns(), mrpt::math::CMatrixTemplate< mrpt::math::TPoint3D >::extractRows(), mrpt::hwdrivers::CRoboticHeadInterface::Get3SoundBuffer(), mrpt::math::CMatrixTemplate< mrpt::math::TPoint3D >::resize(), and mrpt::vision::detail::trackFeatures_addNewFeats_simple_list().

◆ size()

template<class T >

CMatrixTemplateSize mrpt::math::CMatrixTemplate< T >::size ( ) const

inline

Get a 2-vector with [NROWS NCOLS] (as in MATLAB command size(x))

Definition at line 304 of file CMatrixTemplate.h.

◆ swap()

template<class T >

void mrpt::math::CMatrixTemplate< T >::swap ( CMatrixTemplate< T > & o )

inline

Swap with another matrix very efficiently (just swaps a pointer and two integer values).

Definition at line 166 of file CMatrixTemplate.h.

Member Data Documentation

◆ m_Cols

template<class T >

size_t mrpt::math::CMatrixTemplate< T >::m_Cols

protected

Definition at line 85 of file CMatrixTemplate.h.

◆ m_Rows

template<class T >

size_t mrpt::math::CMatrixTemplate< T >::m_Rows

protected

Definition at line 85 of file CMatrixTemplate.h.

◆ m_Val

template<class T >

T** mrpt::math::CMatrixTemplate< T >::m_Val

protected

Definition at line 84 of file CMatrixTemplate.h.

Detailed Description

template<class T> class mrpt::math::CMatrixTemplate< T >

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Member Typedef Documentation

◆ const_reference

◆ difference_type

◆ reference

◆ size_type

◆ value_type

Constructor & Destructor Documentation

◆ CMatrixTemplate() [1/5]

◆ CMatrixTemplate() [2/5]

◆ CMatrixTemplate() [3/5]

◆ CMatrixTemplate() [4/5]

◆ CMatrixTemplate() [5/5]

◆ ~CMatrixTemplate()

Member Function Documentation

◆ appendCol()

◆ appendRow()

◆ ASSERT_ENOUGHROOM()

◆ cols()

◆ extractCol() [1/2]

◆ extractCol() [2/2]

◆ extractColumns()

◆ extractRows()

◆ extractSubmatrix() [1/2]

◆ extractSubmatrix() [2/2]

◆ fillAll()

◆ get_unsafe() [1/2]

◆ get_unsafe() [2/2]

◆ get_unsafe_row() [1/2]

◆ get_unsafe_row() [2/2]

◆ getAsVector()

◆ insertCol()

◆ operator()() [1/5]

◆ operator()() [2/5]

◆ operator()() [3/5]

◆ operator()() [4/5]

◆ operator()() [5/5]

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ realloc()

◆ resize()

◆ rows()

◆ set_unsafe()

◆ setSize()

◆ size()

◆ swap()

Member Data Documentation

◆ m_Cols

◆ m_Rows

◆ m_Val

template<class T>
class mrpt::math::CMatrixTemplate< T >