Матричные посредники (matrix proxies)

Строка матрицы

Описание

Шаблонный класс matrix_row<M> позволяет работать со строкой матрицы.

Пример

#include <boost/numeric/ublas/matrix.hpp>
#include <boost/numeric/ublas/matrix_proxy.hpp>
#include <boost/numeric/ublas/io.hpp>

int main () {
    using namespace boost::numeric::ublas;
    matrix<double> m (3, 3);
    for (unsigned i = 0; i < m.size1 (); ++ i) {
        matrix_row<matrix<double> > mr (m, i);
        for (unsigned j = 0; j < mr.size (); ++ j)
            mr (j) = 3 * i + j;
        std::cout << mr << std::endl;
    }
}

Будет выведено на экран:

[3](0,1,2)
[3](3,4,5)
[3](6,7,8)

Определение

Определен в заголовочном файле matrix_proxy.hpp.

Параметры шаблона

Параметр	Описание	Значение по-умолчанию
`M`	Тип связанной матрицы.

Является моделью

Vector Expression .

Требования к типам данных

Для которых базовый класс Vector Expression .

Базовый класс

vector_expression<matrix_row<M> >

Функции-члены

Приведенные ниже функции-члены в основном аналогичны функциям, перевод которым дан в разделе вектор. Характерные только для matrix_row функции-члены переведены в таблице ниже.

Функция-член	Описание
`matrix_row (matrix_type &data, size_type i)`	Создает под-вектор из строки с номером `size_type` матрицы `data`.
`size_type size () const`	Returns the size of the sub vector.
`const_reference operator () (size_type i) const`	Returns the value of the `i`-th element.
`reference operator () (size_type i)`	Returns a reference of the `i`-th element.
`matrix_row &operator = (const matrix_row &mr)`	The assignment operator.
`matrix_row &assign_temporary (matrix_row &mr)`	Assigns a temporary. May change the matrix row `mr` .
`template<class AE> matrix_row &operator = (const vector_expression<AE> &ae)`	The extended assignment operator.
`template<class AE> matrix_row &assign (const vector_expression<AE> &ae)`	Assigns a vector expression to the sub vector. Left and right hand side of the assignment should be independent.
`template<class AE> matrix_row &operator += (const vector_expression<AE> &ae)`	A computed assignment operator. Adds the vector expression to the sub vector.
`template<class AE> matrix_row &plus_assign (const vector_expression<AE> &ae)`	Adds a vector expression to the sub vector. Left and right hand side of the assignment should be independent.
`template<class AE> matrix_row &operator -= (const vector_expression<AE> &ae)`	A computed assignment operator. Subtracts the vector expression from the sub vector.
`template<class AE> matrix_row &minus_assign (const vector_expression<AE> &ae)`	Subtracts a vector expression from the sub vector. Left and right hand side of the assignment should be independent.
`template<class AT> matrix_row &operator *= (const AT &at)`	A computed assignment operator. Multiplies the sub vector with a scalar.
`template<class AT> matrix_row &operator /= (const AT &at)`	A computed assignment operator. Divides the sub vector through a scalar.
`void swap (matrix_row &mr)`	Swaps the contents of the sub vectors.
`const_iterator begin () const`	Returns a `const_iterator` pointing to the beginning of the `matrix_row`.
`const_iterator end () const`	Returns a `const_iterator` pointing to the end of the `matrix_row`.
`iterator begin ()`	Returns a `iterator` pointing to the beginning of the `matrix_row`.
`iterator end ()`	Returns a `iterator` pointing to the end of the `matrix_row`.
`const_reverse_iterator rbegin () const`	Returns a `const_reverse_iterator` pointing to the beginning of the reversed `matrix_row`.
`const_reverse_iterator rend () const`	Returns a `const_reverse_iterator` pointing to the end of the reversed `matrix_row`.
`reverse_iterator rbegin ()`	Returns a `reverse_iterator` pointing to the beginning of the reversed `matrix_row`.
`reverse_iterator rend ()`	Returns a `reverse_iterator` pointing to the end of the reversed `matrix_row`.

Проекции

Независимые функции row поддерживают создание строк матриц.


    template<class M> matrix_row<M> row (M &data, std::size_t i);
    template<class M> const matrix_row<const M> row (const M &data, std::size_t i);

Определение

Определено в заголовочном файле matrix_proxy.hpp.

Требования к типам данных

M является моделью Matrix Expression .

Примеры

#include <boost/numeric/ublas/matrix.hpp>
#include <boost/numeric/ublas/matrix_proxy.hpp>
#include <boost/numeric/ublas/io.hpp>

int main () {
    using namespace boost::numeric::ublas;
    matrix<double> m (3, 3);
    for (unsigned i = 0; i < m.size1 (); ++ i) {
        for (unsigned j = 0; j < m.size2 (); ++ j)
            row (m, i) (j) = 3 * i + j;
        std::cout << row (m, i) << std::endl;
    }
}

Будет выведено на экран:

[3](0,1,2)
[3](3,4,5)
[3](6,7,8)

Столбец матрицы

Описание

Шаблонный класс matrix_column<M> позволяет работать со столбцом матрицы.

Пример

#include <boost/numeric/ublas/matrix.hpp>
#include <boost/numeric/ublas/matrix_proxy.hpp>
#include <boost/numeric/ublas/io.hpp>

int main () {
    using namespace boost::numeric::ublas;
    matrix<double> m (3, 3);
    for (unsigned j = 0; j < m.size2 (); ++ j) {
        matrix_column<matrix<double> > mc (m, j);
        for (unsigned i = 0; i < mc.size (); ++ i)
            mc (i) = 3 * i + j;
        std::cout << mc << std::endl;
    }
}

Будет выведено на экран:

[3](0,3,6)
[3](1,4,7)
[3](2,5,8)

Определение

Определен в заголовочном файле matrix_proxy.hpp.

Параметры шаблона

Параметр	Описание	Значение по-умолчанию
`M`	Тип связанной матрицы.

Является моделью

Vector Expression .

Требования к типам данных

Для которых базовый класс Vector Expression .

Базовый класс

vector_expression<matrix_column<M> >

Функции-члены

Приведенные ниже функции-члены в основном аналогичны функциям, перевод которым дан в разделе вектор. Характерные только для matrix_column функции-члены переведены в таблице ниже.

Функция-член	Описание
`matrix_column (matrix_type &data, size_type j)`	Создает под-вектор из столбца с номером `size_type` матрицы `data`.
`size_type size () const`	Returns the size of the sub vector.
`const_reference operator () (size_type i) const`	Returns the value of the `i`-th element.
`reference operator () (size_type i)`	Returns a reference of the `i`-th element.
`matrix_column &operator = (const matrix_column &mc)`	The assignment operator.
`matrix_column &assign_temporary (matrix_column &mc)`	Assigns a temporary. May change the matrix column `mc` .
`template<class AE> matrix_column &operator = (const vector_expression<AE> &ae)`	The extended assignment operator.
`template<class AE> matrix_column &assign (const vector_expression<AE> &ae)`	Assigns a vector expression to the sub vector. Left and right hand side of the assignment should be independent.
`template<class AE> matrix_column &operator += (const vector_expression<AE> &ae)`	A computed assignment operator. Adds the vector expression to the sub vector.
`template<class AE> matrix_column &plus_assign (const vector_expression<AE> &ae)`	Adds a vector expression to the sub vector. Left and right hand side of the assignment should be independent.
`template<class AE> matrix_column &operator -= (const vector_expression<AE> &ae)`	A computed assignment operator. Subtracts the vector expression from the sub vector.
`template<class AE> matrix_column &minus_assign (const vector_expression<AE> &ae)`	Subtracts a vector expression from the sub vector. Left and right hand side of the assignment should be independent.
`template<class AT> matrix_column &operator *= (const AT &at)`	A computed assignment operator. Multiplies the sub vector with a scalar.
`template<class AT> matrix_column &operator /= (const AT &at)`	A computed assignment operator. Divides the sub vector through a scalar.
`void swap (matrix_column &mc)`	Swaps the contents of the sub vectors.
`const_iterator begin () const`	Returns a `const_iterator` pointing to the beginning of the `matrix_column`.
`const_iterator end () const`	Returns a `const_iterator` pointing to the end of the `matrix_column`.
`iterator begin ()`	Returns a `iterator` pointing to the beginning of the `matrix_column`.
`iterator end ()`	Returns a `iterator` pointing to the end of the `matrix_column`.
`const_reverse_iterator rbegin () const`	Returns a `const_reverse_iterator` pointing to the beginning of the reversed `matrix_column`.
`const_reverse_iterator rend () const`	Returns a `const_reverse_iterator` pointing to the end of the reversed `matrix_column`.
`reverse_iterator rbegin ()`	Returns a `reverse_iterator` pointing to the beginning of the reversed `matrix_column`.
`reverse_iterator rend ()`	Returns a `reverse_iterator` pointing to the end of the reversed `matrix_column`.

Проекции

Описание

Независимые функции column поддерживают создание столбцов матриц.


    template<class M> matrix_column<M> column (M &data, std::size_t j);  
    template<class M> const matrix_column<const M> column (const M &data, std::size_t j);

Определение

Определен в заголовочном файле matrix_proxy.hpp.

Требования к типам данных

M является моделью Matrix Expression .

Пример

#include <boost/numeric/ublas/matrix.hpp>
#include<boost/numeric/ublas/matrix_proxy.hpp>
#include<boost/numeric/ublas/io.hpp>

int main () {
    using namespace boost::numeric::ublas;
    matrix<double> m (3, 3);
    for (unsigned j = 0; j < m.size2 (); ++ j) {
        for (unsigned i = 0; i < m.size1 (); ++ i)
            column (m, j) (i) = 3 * i + j;
        std::cout << column (m, j) << std::endl;
    }
}

Будет выведено на экран:

[3](0,3,6)
[3](1,4,7)
[3](2,5,8)

Диапазон вектора

Описание

Шаблонный класс matrix_vector_range<M> позволяет работать с подвектором матрицы.

Пример

#include <boost/numeric/ublas/matrix.hpp>
#include <boost/numeric/ublas/matrix_proxy.hpp>
#include <boost/numeric/ublas/io.hpp>

int main () {
    using namespace boost::numeric::ublas;
    matrix<double> m (3, 3);
    for (unsigned i = 0; i < m.size1 (); ++ i)
        for (unsigned j = 0; j < m.size2 (); ++ j)
            m (i, j) = 3 * i + j;

    matrix_vector_range<matrix<double> > mvr (m, range (0, 3), range (0, 3));
    std::cout << mvr << std::endl;
}

Будет выведено на экран:

[3](0,4,8)

Определение

Определен в заголовочном файле matrix_proxy.hpp.

Параметры шаблона

Параметр	Описание	Значение по-умолчанию
`M`	Тип связанной матрицы.

Является моделью

Vector Expression .

Требования к типам данных

Для которых базовый класс Vector Expression .

Базовый класс

vector_expression<matrix_vector_range<M> >

Функции-члены

Приведенные ниже функции-члены в основном аналогичны функциям, перевод которым дан в разделе вектор. Характерные только для matrix_vector_range функции-члены переведены в таблице ниже.

Функция-член	Описание
`matrix_vector_range (matrix_type &data, const range &r1, const range &r2)`	Создает под-вектор из матрицы `data`, определяемый двумя диапазонами `r1` и `r2`.
`size_type size () const`	Returns the size of the sub vector.
`const_reference operator () (size_type i) const`	Returns the value of the `i`-th element.
`reference operator () (size_type i)`	Returns a reference of the `i`-th element.
`matrix_vector_range &operator = (const matrix_vector_range &mvr)`	The assignment operator.
`matrix_vector_range &assign_temporary (matrix_vector_range &mvr)`	Assigns a temporary. May change the matrix vector range `mvr`.
`template<class AE> matrix_vector_range &operator = (const vector_expression<AE> &ae)`	The extended assignment operator.
`template<class AE> matrix_vector_range &assign (const vector_expression<AE> &ae)`	Assigns a vector expression to the sub vector. Left and right hand side of the assignment should be independent.
`template<class AE> matrix_vector_range &operator += (const vector_expression<AE> &ae)`	A computed assignment operator. Adds the vector expression to the sub vector.
`template<class AE> matrix_vector_range &plus_assign (const vector_expression<AE> &ae)`	Adds a vector expression to the sub vector. Left and right hand side of the assignment should be independent.
`template<class AE> matrix_vector_range &operator -= (const vector_expression<AE> &ae)`	A computed assignment operator. Subtracts the vector expression from the sub vector.
`template<class AE> matrix_vector_range &minus_assign (const vector_expression<AE> &ae)`	Subtracts a vector expression from the sub vector. Left and right hand side of the assignment should be independent.
`template<class AT> matrix_vector_range &operator *= (const AT &at)`	A computed assignment operator. Multiplies the sub vector with a scalar.
`template<class AT> matrix_vector_range &operator /= (const AT &at)`	A computed assignment operator. Divides the sub vector through a scalar.
`void swap (matrix_vector_range &mvr)`	Swaps the contents of the sub vectors.
`const_iterator begin () const`	Returns a `const_iterator` pointing to the beginning of the `matrix_vector_range`.
`const_iterator end () const`	Returns a `const_iterator` pointing to the end of the `matrix_vector_range`.
`iterator begin ()`	Returns a `iterator` pointing to the beginning of the `matrix_vector_range`.
`iterator end ()`	Returns a `iterator` pointing to the end of the `matrix_vector_range`.
`const_reverse_iterator rbegin () const`	Returns a `const_reverse_iterator` pointing to the beginning of the `matrix_vector_range`.
`const_reverse_iterator rend () const`	Returns a `const_reverse_iterator` pointing to the end of the reversed `matrix_vector_range`.
`reverse_iterator rbegin ()`	Returns a `reverse_iterator` pointing to the beginning of the reversed `matrix_vector_range`.
`reverse_iterator rend ()`	Returns a `reverse_iterator` pointing to the end of the reversed `matrix_vector_range`.

Выборка вектора

Описание

Шаблонный класс matrix_vector_slice<M> позволяет работать с выборкой подвектора матрицы.

Пример

#include<boost/numeric/ublas/matrix.hpp>
#include<boost/numeric/ublas/matrix_proxy.hpp>
#include<boost/numeric/ublas/io.hpp>

int main () {
    using namespace boost::numeric::ublas;
    matrix<double> m (3, 3);
    for (unsigned i = 0; i < m.size1 (); ++ i)
        for (unsigned j = 0; j < m.size2 (); ++ j)
            m (i, j) = 3 * i + j;

    matrix_vector_slice<matrix<double> > mvs (m, slice (0, 1, 3), slice (0, 1, 3));
    std::cout << mvs << std::endl;
}

Будет выведено на экран:

[3](0,4,8)

Определение

Определен в заголовочном файле matrix_proxy.hpp.

Параметры шаблона

Параметр	Описание	Значение по-умолчанию
`M`	Тип связанной матрицы.

Является моделью

Vector Expression .

Требования к типам данных

Для которых базовый класс Vector Expression .

Базовый класс

vector_expression<matrix_vector_slice<M> >

Функции-члены

Приведенные ниже функции-члены в основном аналогичны функциям, перевод которым дан в разделе вектор. Характерные только для matrix_vector_slice функции-члены переведены в таблице ниже.

Функция-член	Описание
`matrix_vector_slice (matrix_type &data, const slice &s1, const slice &s2)`	Создает под-вектор из матрицы `data`, определяемый двумя выборками `s1` и `s2`.
`size_type size () const`	Returns the size of the sub vector.
`const_reference operator () (size_type i) const`	Returns the value of the `i`-th element.
`reference operator () (size_type i)`	Returns a reference of the `i`-th element.
`matrix_vector_slice &operator = (const matrix_vector_slice &mvs)`	The assignment operator.
`matrix_vector_slice &assign_temporary (matrix_vector_slice &mvs)`	Assigns a temporary. May change the matrix vector slice `vs`.
`template<class AE> matrix_vector_slice &operator = (const vector_expression<AE> &ae)`	The extended assignment operator.
`template<class AE> matrix_vector_slice &assign (const vector_expression<AE> &ae)`	Assigns a vector expression to the sub vector. Left and right hand side of the assignment should be independent.
`template<class AE> matrix_vector_slice &operator += (const vector_expression<AE> &ae)`	A computed assignment operator. Adds the vector expression to the sub vector.
`template<class AE> matrix_vector_slice &plus_assign (const vector_expression<AE> &ae)`	Adds a vector expression to the sub vector. Left and right hand side of the assignment should be independent.
`template<class AE> matrix_vector_slice &operator -= (const vector_expression<AE> &ae)`	A computed assignment operator. Subtracts the vector expression from the sub vector.
`template<class AE> matrix_vector_slice &minus_assign (const vector_expression<AE> &ae)`	Subtracts a vector expression from the sub vector. Left and right hand side of the assignment should be independent.
`template<class AT> matrix_vector_slice &operator *= (const AT &at)`	A computed assignment operator. Multiplies the sub vector with a scalar.
`template<class AT> matrix_vector_slice &operator /= (const AT &at)`	A computed assignment operator. Divides the sub vector through a scalar.
`void swap (matrix_vector_slice &mvs)`	Swaps the contents of the sub vectors.
`const_iterator begin () const`	Returns a `const_iterator` pointing to the beginning of the `matrix_vector_slice`.
`const_iterator end () const`	Returns a `const_iterator` pointing to the end of the `matrix_vector_slice`.
`iterator begin ()`	Returns a `iterator` pointing to the beginning of the `matrix_vector_slice`.
`iterator end ()`	Returns a `iterator` pointing to the end of the `matrix_vector_slice`.
`const_reverse_iterator rbegin () const`	Returns a `const_reverse_iterator` pointing to the beginning of the reversed `matrix_vector_slice`.
`const_reverse_iterator rend () const`	Returns a `const_reverse_iterator` pointing to the end of the reversed `matrix_vector_slice`.
`reverse_iterator rbegin ()`	Returns a `reverse_iterator` pointing to the beginning of the reversed `matrix_vector_slice`.
`reverse_iterator rend ()`	Returns a `reverse_iterator` pointing to the end of the reversed `matrix_vector_slice`.

Диапазон матрицы

Описание

Шаблонный класс matrix_range<M> позволяет работать с подматрицей матрицы.

Пример

#include <boost/numeric/ublas/matrix.hpp>
#include <boost/numeric/ublas/matrix_proxy.hpp>
#include <boost/numeric/ublas/io.hpp>

int main () {
    using namespace boost::numeric::ublas;
    matrix<double> m (3, 3);
    matrix_range<matrix<double> > mr (m, range (0, 3), range (0, 3));
    for (unsigned i = 0; i < mr.size1 (); ++ i)
        for (unsigned j = 0; j < mr.size2 (); ++ j)
            mr (i, j) = 3 * i + j;
    std::cout << mr << std::endl;
}

Будет выведено на экран:

[3,3]((0,1,2),(3,4,5),(6,7,8))

Определение

Определен в заголовочном файле matrix_proxy.hpp.

Параметры шаблона

Параметр	Описание	Значение по-умолчанию
`M`	Тип связанной матрицы.

Является моделью

Matrix Expression .

Требования к типам данных

Для которых базовый класс Matrix Expression .

Базовый класс

matrix_expression<matrix_range<M> >

Функции-члены

Приведенные ниже функции-члены в основном аналогичны функциям, перевод которым дан в разделе матрица. Характерные только для matrix_range функции-члены переведены в таблице ниже.

Функция-член	Описание
`matrix_range (matrix_type &data, const range &r1, const range &r2)`	Создает подматрицу из матрицы `data`, определяемую двумя диапазонами `r1` и `r2`.
`size_type start1 () const`	Возвращает индекс первой строки.
`size_type size1 () const`	Возвращает число строк.
`size_type start2 () const`	Возвращает индекс первого столбца.
`size_type size2 () const`	Возвращает число столбцов.
`const_reference operator () (size_type i, size_type j) const`	Returns the value of the `j`-th element in the `i`-th row.
`reference operator () (size_type i, size_type j)`	Returns a reference of the `j`-th element in the `i`-th row.
`matrix_range &operator = (const matrix_range &mr)`	The assignment operator.
`matrix_range &assign_temporary (matrix_range &mr)`	Assigns a temporary. May change the matrix range `mr` .
`template<class AE> matrix_range &operator = (const matrix_expression<AE> &ae)`	The extended assignment operator.
`template<class AE> matrix_range &assign (const matrix_expression<AE> &ae)`	Assigns a matrix expression to the sub matrix. Left and right hand side of the assignment should be independent.
`template<class AE> matrix_range &operator += (const matrix_expression<AE> &ae)`	A computed assignment operator. Adds the matrix expression to the sub matrix.
`template<class AE> matrix_range &plus_assign (const matrix_expression<AE> &ae)`	Adds a matrix expression to the sub matrix. Left and right hand side of the assignment should be independent.
`template<class AE> matrix_range &operator -= (const matrix_expression<AE> &ae)`	A computed assignment operator. Subtracts the matrix expression from the sub matrix.
`template<class AE> matrix_range &minus_assign (const matrix_expression<AE> &ae)`	Subtracts a matrix expression from the sub matrix. Left and right hand side of the assignment should be independent.
`template<class AT> matrix_range &operator *= (const AT &at)`	A computed assignment operator. Multiplies the sub matrix with a scalar.
`template<class AT> matrix_range &operator /= (const AT &at)`	A computed assignment operator. Divides the sub matrix through a scalar.
`void swap (matrix_range &mr)`	Swaps the contents of the sub matrices.
`const_iterator1 begin1 () const`	Returns a `const_iterator1` pointing to the beginning of the `matrix_range`.
`const_iterator1 end1 () const`	Returns a `const_iterator1` pointing to the end of the `matrix_range`.
`iterator1 begin1 ()`	Returns a `iterator1` pointing to the beginning of the `matrix_range`.
`iterator1 end1 ()`	Returns a `iterator1` pointing to the end of the `matrix_range`.
`const_iterator2 begin2 () const`	Returns a `const_iterator2` pointing to the beginning of the `matrix_range`.
`const_iterator2 end2 () const`	Returns a `const_iterator2` pointing to the end of the `matrix_range`.
`iterator2 begin2 ()`	Returns a `iterator2` pointing to the beginning of the `matrix_range`.
`iterator2 end2 ()`	Returns a `iterator2` pointing to the end of the `matrix_range`.
`const_reverse_iterator1 rbegin1 () const`	Returns a `const_reverse_iterator1` pointing to the beginning of the reversed `matrix_range`.
`const_reverse_iterator1 rend1 () const`	Returns a `const_reverse_iterator1` pointing to the end of the reversed `matrix_range`.
`reverse_iterator1 rbegin1 ()`	Returns a `reverse_iterator1` pointing to the beginning of the reversed `matrix_range`.
`reverse_iterator1 rend1 ()`	Returns a `reverse_iterator1` pointing to the end of the reversed `matrix_range`.
`const_reverse_iterator2 rbegin2 () const`	Returns a `const_reverse_iterator2` pointing to the beginning of the reversed `matrix_range`.
`const_reverse_iterator2 rend2 () const`	Returns a `const_reverse_iterator2` pointing to the end of the reversed `matrix_range`.
`reverse_iterator2 rbegin2 ()`	Returns a `reverse_iterator2` pointing to the beginning of the reversed `matrix_range`.
`reverse_iterator2 rend2 ()`	Returns a `reverse_iterator2` pointing to the end of reversed the `matrix_range`.

Simple Projections

Описание

The free subrange functions support the construction of matrix ranges.

Prototypes


    template<class M>
    matrix_range<M> subrange (M &data,
       M::size_type start1, M::size_type stop1, M::size_type start2, M::size_type, stop2);
    template<class M>
    const matrix_range<const M> subrange (const M &data,
       M::size_type start1, M::size_type stop1, M::size_type start2, M::size_type, stop2);

Generic Projections

Описание

The free project functions support the construction of matrix ranges. Existing matrix_range's can be composed with further ranges. The resulting ranges are computed using this existing ranges' compose function.

Prototypes


    template<class M>
    matrix_range<M> project (M &data, const range &r1, const range &r2);
    template<class M>
    const matrix_range<const M> project (const M &data, const range &r1, const range &r2);
    template<class M>
    matrix_range<M> project (matrix_range<M> &data, const range &r1, const range &r2);
    template<class M>
    const matrix_range<M> project (const matrix_range<M> &data, const range &r1, const range &r2);

Определение

Определен в заголовочном файле matrix_proxy.hpp.

Требования к типам данных

M is a Является моделью Matrix Expression .

Complexity

Quadratic depending from the size of the ranges.

Пример

#include<boost/numeric/ublas/matrix.hpp>
#include<boost/numeric/ublas/matrix_proxy.hpp>
#include<boost/numeric/ublas/io.hpp>

int main () {
    using namespace boost::numeric::ublas;
    matrix<double> m (3, 3);
    for (unsigned i = 0; i < m.size1 (); ++ i)
        for (unsigned j = 0; j < m.size2 (); ++ j)
            project (m, range (0, 3), range (0, 3)) (i, j) = 3 * i + j;
    std::cout << project (m, range (0, 3), range (0, 3)) << std::endl;
}

Matrix Slice

Описание

Шаблонный класс matrix_slice<M> allows addressing a sliced sub matrix of a matrix.

Пример

#include<boost/numeric/ublas/matrix.hpp>
#include<boost/numeric/ublas/matrix_proxy.hpp>
#include<boost/numeric/ublas/io.hpp>

int main () {
    using namespace boost::numeric::ublas;
    matrix<double> m (3, 3);
    matrix_slice<matrix<double> > ms (m, slice (0, 1, 3), slice (0, 1, 3));
    for (unsigned i = 0; i < ms.size1 (); ++ i)
        for (unsigned j = 0; j < ms.size2 (); ++ j)
            ms (i, j) = 3 * i + j;
    std::cout << ms << std::endl;
}

Определение

Определен в заголовочном файле matrix_proxy.hpp.

Параметры шаблона

Параметр	Описание	Значение по-умолчанию
`M`	The type of matrix referenced.

Является моделью

Matrix Expression .

If the specified slices fall outside that of the index range of the matrix, then the matrix_slice is not a well formed Matrix Expression. That is, access to an element which is outside of the matrix is undefined.

Требования к типам данных

None, except for those imposed by the requirements of Matrix Expression .

Базовый класс

matrix_expression<matrix_slice<M> >

Members

Member	Описание
`matrix_slice (matrix_type &data, const slice &s1, const slice &s2)`	Constructs a sub matrix.
`size_type size1 () const`	Returns the number of rows.
`size_type size2 () const`	Returns the number of columns.
`const_reference operator () (size_type i, size_type j) const`	Returns the value of the `j`-th element in the `i`-th row.
`reference operator () (size_type i, size_type j)`	Returns a reference of the `j`-th element in the `i`-th row.
`matrix_slice &operator = (const matrix_slice &ms)`	The assignment operator.
`matrix_slice &assign_temporary (matrix_slice &ms)`	Assigns a temporary. May change the matrix slice `ms` .
`template<class AE> matrix_slice &operator = (const matrix_expression<AE> &ae)`	The extended assignment operator.
`template<class AE> matrix_slice &assign (const matrix_expression<AE> &ae)`	Assigns a matrix expression to the sub matrix. Left and right hand side of the assignment should be independent.
`template<class AE> matrix_slice &operator += (const matrix_expression<AE> &ae)`	A computed assignment operator. Adds the matrix expression to the sub matrix.
`template<class AE> matrix_slice &plus_assign (const matrix_expression<AE> &ae)`	Adds a matrix expression to the sub matrix. Left and right hand side of the assignment should be independent.
`template<class AE> matrix_slice &operator -= (const matrix_expression<AE> &ae)`	A computed assignment operator. Subtracts the matrix expression from the sub matrix.
`template<class AE> matrix_slice &minus_assign (const matrix_expression<AE> &ae)`	Subtracts a matrix expression from the sub matrix. Left and right hand side of the assignment should be independent.
`template<class AT> matrix_slice &operator *= (const AT &at)`	A computed assignment operator. Multiplies the sub matrix with a scalar.
`template<class AT> matrix_slice &operator /= (const AT &at)`	A computed assignment operator. Multiplies the sub matrix through a scalar.
`void swap (matrix_slice &ms)`	Swaps the contents of the sub matrices.
`const_iterator1 begin1 () const`	Returns a `const_iterator1` pointing to the beginning of the `matrix_slice`.
`const_iterator1 end1 () const`	Returns a `const_iterator1` pointing to the end of the `matrix_slice`.
`iterator1 begin1 ()`	Returns a `iterator1` pointing to the beginning of the `matrix_slice`.
`iterator1 end1 ()`	Returns a `iterator1` pointing to the end of the `matrix_slice`.
`const_iterator2 begin2 () const`	Returns a `const_iterator2` pointing to the beginning of the `matrix_slice`.
`const_iterator2 end2 () const`	Returns a `const_iterator2` pointing to the end of the `matrix_slice`.
`iterator2 begin2 ()`	Returns a `iterator2` pointing to the beginning of the `matrix_slice`.
`iterator2 end2 ()`	Returns a `iterator2` pointing to the end of the `matrix_slice`.
`const_reverse_iterator1 rbegin1 () const`	Returns a `const_reverse_iterator1` pointing to the beginning of the reversed `matrix_slice`.
`const_reverse_iterator1 rend1 () const`	Returns a `const_reverse_iterator1` pointing to the end of the reversed `matrix_slice`.
`reverse_iterator1 rbegin1 ()`	Returns a `reverse_iterator1` pointing to the beginning of the reversed `matrix_slice`.
`reverse_iterator1 rend1 ()`	Returns a `reverse_iterator1` pointing to the end of the reversed `matrix_slice`.
`const_reverse_iterator2 rbegin2 () const`	Returns a `const_reverse_iterator2` pointing to the beginning of the reversed `matrix_slice`.
`const_reverse_iterator2 rend2 () const`	Returns a `const_reverse_iterator2` pointing to the end of the reversed `matrix_slice`.
`reverse_iterator2 rbegin2 ()`	Returns a `reverse_iterator2` pointing to the beginning of the reversed `matrix_slice`.
`reverse_iterator2 rend2 ()`	Returns a `reverse_iterator2` pointing to the end of the reversed `matrix_slice`.

Simple Projections

Описание

The free subslice functions support the construction of matrix slices.

Prototypes


    template<class M>
    matrix_slice<M> subslice (M &data,
       M::size_type start1, M::difference_type stride1, M::size_type size1,
       M::size_type start2, M::difference_type stride2, M::size_type size2);
    template<class M>
    const matrix_slice<const M> subslice (const M &data,
       M::size_type start1, M::difference_type stride1, M::size_type size1,
       M::size_type start2, M::difference_type stride2, M::size_type size2);

Generic Projections

Описание

The free project functions support the construction of matrix slices. Existing matrix_slice's can be composed with further ranges or slices. The resulting slices are computed using this existing slices' compose function.

Prototypes


    template<class M>
    matrix_slice<M> project (M &data, const slice &s1, const slice &s2);
    template<class M>
    const matrix_slice<const M> project (const M &data, const slice &s1, const slice &s2);
    template<class M>
    matrix_slice<M> project (matrix_slice<M> &data, const range &r1, const range &r2);
    template<class M>
    const matrix_slice<M> project (const matrix_slice<M> &data, const range &r1, const range &r2);
    template<class M>
    matrix_slice<M> project (matrix_slice<M> &data, const slice &s1, const slice &s2);
    template<class M>
    const matrix_slice<M> project (const matrix_slice<M> &data, const slice &s1, const slice &s2);

Определение

Определен в заголовочном файле matrix_proxy.hpp.

Требования к типам данных

M является моделью Matrix Expression .

Complexity

Quadratic depending from the size of the slices.

Пример

#include<boost/numeric/ublas/matrix.hpp>
#include<boost/numeric/ublas/matrix_proxy.hpp>
#include<boost/numeric/ublas/io.hpp>

int main () {
    using namespace boost::numeric::ublas;
    matrix<double> m (3, 3);
    for (unsigned i = 0; i < m.size1 (); ++ i)
        for (unsigned j = 0; j < m.size2 (); ++ j)
            project (m, slice (0, 1, 3), slice (0, 1, 3)) (i, j) = 3 * i + j;
    std::cout << project (m, slice (0, 1, 3), slice (0, 1, 3)) << std::endl;
}

Copyright (©) 2000-2002 Joerg Walter, Mathias Koch
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