Chris@16: /**
Chris@16:  * -*- c++ -*-
Chris@16:  *
Chris@16:  * \file begin.hpp
Chris@16:  *
Chris@16:  * \brief The \c begin operation.
Chris@16:  *
Chris@16:  * Copyright (c) 2009, Marco Guazzone
Chris@16:  *
Chris@16:  * Distributed under the Boost Software License, Version 1.0. (See
Chris@16:  * accompanying file LICENSE_1_0.txt or copy at
Chris@16:  * http://www.boost.org/LICENSE_1_0.txt)
Chris@16:  *
Chris@16:  * \author Marco Guazzone, marco.guazzone@gmail.com
Chris@16:  */
Chris@16: 
Chris@16: #ifndef BOOST_NUMERIC_UBLAS_OPERATION_BEGIN_HPP
Chris@16: #define BOOST_NUMERIC_UBLAS_OPERATION_BEGIN_HPP
Chris@16: 
Chris@16: 
Chris@16: #include <boost/numeric/ublas/expression_types.hpp>
Chris@16: #include <boost/numeric/ublas/fwd.hpp>
Chris@16: #include <boost/numeric/ublas/traits/const_iterator_type.hpp>
Chris@16: #include <boost/numeric/ublas/traits/iterator_type.hpp>
Chris@16: 
Chris@16: 
Chris@16: namespace boost { namespace numeric { namespace ublas {
Chris@16: 
Chris@16:     namespace detail {
Chris@16: 
Chris@16:         /**
Chris@16:          * \brief Auxiliary class for implementing the \c begin operation.
Chris@16:          * \tparam CategoryT The expression category type (e.g., vector_tag).
Chris@16:          * \tparam TagT The dimension type tag (e.g., tag::major).
Chris@16:          * \tparam OrientationT The orientation category type (e.g., row_major_tag).
Chris@16:          */
Chris@16:         template <typename CategoryT, typename TagT=void, typename OrientationT=void>
Chris@16:         struct begin_impl;
Chris@16: 
Chris@16: 
Chris@16:         /// \brief Specialization of \c begin_impl for iterating vector expressions.
Chris@16:         template <>
Chris@16:         struct begin_impl<vector_tag,void,void>
Chris@16:         {
Chris@16:             /**
Chris@16:              * \brief Return an iterator to the first element of the given vector
Chris@16:              *  expression.
Chris@16:              * \tparam ExprT A model of VectorExpression type.
Chris@16:              * \param e A vector expression.
Chris@16:              * \return An iterator over the given vector expression.
Chris@16:              */
Chris@16:             template <typename ExprT>
Chris@16:             static typename ExprT::iterator apply(ExprT& e)
Chris@16:             {
Chris@16:                 return e.begin();
Chris@16:             }
Chris@16: 
Chris@16: 
Chris@16:             /**
Chris@16:              * \brief Return a const iterator to the first element of the given vector
Chris@16:              *  expression.
Chris@16:              * \tparam ExprT A model of VectorExpression type.
Chris@16:              * \param e A vector expression.
Chris@16:              * \return A const iterator to the first element of the given vector
Chris@16:              *  expression.
Chris@16:              */
Chris@16:             template <typename ExprT>
Chris@16:             static typename ExprT::const_iterator apply(ExprT const& e)
Chris@16:             {
Chris@16:                 return e.begin();
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16: 
Chris@16:         /// \brief Specialization of \c begin_impl for iterating matrix expressions with
Chris@16:         ///  a row-major orientation over the major dimension.
Chris@16:         template <>
Chris@16:         struct begin_impl<matrix_tag,tag::major,row_major_tag>
Chris@16:         {
Chris@16:             /**
Chris@16:              * \brief Return an iterator to the first element of the given row-major
Chris@16:              *  matrix expression over the major dimension.
Chris@16:              * \tparam ExprT A model of MatrixExpression type.
Chris@16:              * \param e A matrix expression.
Chris@16:              * \return An iterator over the major dimension of the given matrix
Chris@16:              *  expression.
Chris@16:              */
Chris@16:             template <typename ExprT>
Chris@16:             static typename ExprT::iterator1 apply(ExprT& e)
Chris@16:             {
Chris@16:                 return e.begin1();
Chris@16:             }
Chris@16: 
Chris@16: 
Chris@16:             /**
Chris@16:              * \brief Return a const iterator to the first element of the given
Chris@16:              *  row-major matrix expression over the major dimension.
Chris@16:              * \tparam ExprT A model of MatrixExpression type.
Chris@16:              * \param e A matrix expression.
Chris@16:              * \return A const iterator over the major dimension of the given matrix
Chris@16:              *  expression.
Chris@16:              */
Chris@16:             template <typename ExprT>
Chris@16:             static typename ExprT::const_iterator1 apply(ExprT const& e)
Chris@16:             {
Chris@16:                 return e.begin1();
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16: 
Chris@16:         /// \brief Specialization of \c begin_impl for iterating matrix expressions with
Chris@16:         ///  a column-major orientation over the major dimension.
Chris@16:         template <>
Chris@16:         struct begin_impl<matrix_tag,tag::major,column_major_tag>
Chris@16:         {
Chris@16:             /**
Chris@16:              * \brief Return an iterator to the first element of the given column-major
Chris@16:              *  matrix expression over the major dimension.
Chris@16:              * \tparam ExprT A model of MatrixExpression type.
Chris@16:              * \param e A matrix expression.
Chris@16:              * \return An iterator over the major dimension of the given matrix
Chris@16:              *  expression.
Chris@16:              */
Chris@16:             template <typename ExprT>
Chris@16:             static typename ExprT::iterator2 apply(ExprT& e)
Chris@16:             {
Chris@16:                 return e.begin2();
Chris@16:             }
Chris@16: 
Chris@16: 
Chris@16:             /**
Chris@16:              * \brief Return a const iterator to the first element of the given
Chris@16:              *  column-major matrix expression over the major dimension.
Chris@16:              * \tparam ExprT A model of MatrixExpression type.
Chris@16:              * \param e A matrix expression.
Chris@16:              * \return A const iterator over the major dimension of the given matrix
Chris@16:              *  expression.
Chris@16:              */
Chris@16:             template <typename ExprT>
Chris@16:             static typename ExprT::const_iterator2 apply(ExprT const& e)
Chris@16:             {
Chris@16:                 return e.begin2();
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16: 
Chris@16:         /// \brief Specialization of \c begin_impl for iterating matrix expressions with
Chris@16:         ///  a row-major orientation over the minor dimension.
Chris@16:         template <>
Chris@16:         struct begin_impl<matrix_tag,tag::minor,row_major_tag>
Chris@16:         {
Chris@16:             /**
Chris@16:              * \brief Return an iterator to the first element of the given row-major
Chris@16:              *  matrix expression over the minor dimension.
Chris@16:              * \tparam ExprT A model of MatrixExpression type.
Chris@16:              * \param e A matrix expression.
Chris@16:              * \return An iterator over the minor dimension of the given matrix
Chris@16:              *  expression.
Chris@16:              */
Chris@16:             template <typename ExprT>
Chris@16:             static typename ExprT::iterator2 apply(ExprT& e)
Chris@16:             {
Chris@16:                 return e.begin2();
Chris@16:             }
Chris@16: 
Chris@16: 
Chris@16:             /**
Chris@16:              * \brief Return a const iterator to the first element of the given
Chris@16:              *  row-major matrix expression over the minor dimension.
Chris@16:              * \tparam ExprT A model of MatrixExpression type.
Chris@16:              * \param e A matrix expression.
Chris@16:              * \return A const iterator over the minor dimension of the given matrix
Chris@16:              *  expression.
Chris@16:              */
Chris@16:             template <typename ExprT>
Chris@16:             static typename ExprT::const_iterator2 apply(ExprT const& e)
Chris@16:             {
Chris@16:                 return e.begin2();
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16: 
Chris@16: 
Chris@16:         /// \brief Specialization of \c begin_impl for iterating matrix expressions with
Chris@16:         ///  a column-major orientation over the minor dimension.
Chris@16:         template <>
Chris@16:         struct begin_impl<matrix_tag,tag::minor,column_major_tag>
Chris@16:         {
Chris@16:             /**
Chris@16:              * \brief Return an iterator to the first element of the given column-major
Chris@16:              *  matrix expression over the minor dimension.
Chris@16:              * \tparam ExprT A model of MatrixExpression type.
Chris@16:              * \param e A matrix expression.
Chris@16:              * \return An iterator over the minor dimension of the given matrix
Chris@16:              *  expression.
Chris@16:              */
Chris@16:             template <typename ExprT>
Chris@16:             static typename ExprT::iterator1 apply(ExprT& e)
Chris@16:             {
Chris@16:                 return e.begin1();
Chris@16:             }
Chris@16: 
Chris@16: 
Chris@16:             /**
Chris@16:              * \brief Return a const iterator to the first element of the given
Chris@16:              *  column-major matrix expression over the minor dimension.
Chris@16:              * \tparam ExprT A model of MatrixExpression type.
Chris@16:              * \param e A matrix expression.
Chris@16:              * \return A const iterator over the minor dimension of the given matrix
Chris@16:              *  expression.
Chris@16:              */
Chris@16:             template <typename ExprT>
Chris@16:             static typename ExprT::const_iterator1 apply(ExprT const& e)
Chris@16:             {
Chris@16:                 return e.begin1();
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16:     } // Namespace detail
Chris@16: 
Chris@16: 
Chris@16:     /**
Chris@16:      * \brief An iterator to the first element of the given vector expression.
Chris@16:      * \tparam ExprT A model of VectorExpression type.
Chris@16:      * \param e A vector expression.
Chris@16:      * \return An iterator to the first element of the given vector expression.
Chris@16:      */
Chris@16:     template <typename ExprT>
Chris@16:     BOOST_UBLAS_INLINE
Chris@16:     typename ExprT::iterator begin(vector_expression<ExprT>& e)
Chris@16:     {
Chris@16:         return detail::begin_impl<typename ExprT::type_category>::apply(e());
Chris@16:     }
Chris@16: 
Chris@16: 
Chris@16:     /**
Chris@16:      * \brief A const iterator to the first element of the given vector expression.
Chris@16:      * \tparam ExprT A model of VectorExpression type.
Chris@16:      * \param e A vector expression.
Chris@16:      * \return A const iterator to the first element of the given vector expression.
Chris@16:      */
Chris@16:     template <typename ExprT>
Chris@16:     BOOST_UBLAS_INLINE
Chris@16:     typename ExprT::const_iterator begin(vector_expression<ExprT> const& e)
Chris@16:     {
Chris@16:         return detail::begin_impl<typename ExprT::type_category>::apply(e());
Chris@16:     }
Chris@16: 
Chris@16: 
Chris@16:     /**
Chris@16:      * \brief An iterator to the first element of the given matrix expression
Chris@16:      *  according to its orientation.
Chris@16:      * \tparam DimTagT A dimension tag type (e.g., tag::major).
Chris@16:      * \tparam ExprT A model of MatrixExpression type.
Chris@16:      * \param e A matrix expression.
Chris@16:      * \return An iterator to the first element of the given matrix expression
Chris@16:      *  according to its orientation.
Chris@16:      */
Chris@16:     template <typename TagT, typename ExprT>
Chris@16:     BOOST_UBLAS_INLINE
Chris@16:     typename iterator_type<ExprT,TagT>::type begin(matrix_expression<ExprT>& e)
Chris@16:     {
Chris@16:         return detail::begin_impl<typename ExprT::type_category, TagT, typename ExprT::orientation_category>::apply(e());
Chris@16:     }
Chris@16: 
Chris@16: 
Chris@16:     /**
Chris@16:      * \brief A const iterator to the first element of the given matrix expression
Chris@16:      *  according to its orientation.
Chris@16:      * \tparam TagT A dimension tag type (e.g., tag::major).
Chris@16:      * \tparam ExprT A model of MatrixExpression type.
Chris@16:      * \param e A matrix expression.
Chris@16:      * \return A const iterator to the first element of the given matrix expression
Chris@16:      *  according to its orientation.
Chris@16:      */
Chris@16:     template <typename TagT, typename ExprT>
Chris@16:     BOOST_UBLAS_INLINE
Chris@16:     typename const_iterator_type<ExprT,TagT>::type begin(matrix_expression<ExprT> const& e)
Chris@16:     {
Chris@16:         return detail::begin_impl<typename ExprT::type_category, TagT, typename ExprT::orientation_category>::apply(e());
Chris@16:     }
Chris@16: 
Chris@16: 
Chris@16:     /**
Chris@16:      * \brief An iterator to the first element over the dual dimension of the given
Chris@16:      *  iterator.
Chris@16:      * \tparam IteratorT A model of Iterator type.
Chris@16:      * \param it An iterator.
Chris@16:      * \return An iterator to the first element over the dual dimension of the given
Chris@16:      *  iterator.
Chris@16:      */
Chris@16:     template <typename IteratorT>
Chris@16:     BOOST_UBLAS_INLINE
Chris@16:     typename IteratorT::dual_iterator_type begin(IteratorT& it)
Chris@16:     {
Chris@16:         return it.begin();
Chris@16:     }
Chris@16: 
Chris@16: 
Chris@16:     /**
Chris@16:      * \brief A const iterator to the first element over the dual dimension of the
Chris@16:      *  given iterator.
Chris@16:      * \tparam IteratorT A model of Iterator type.
Chris@16:      * \param it An iterator.
Chris@16:      * \return A const iterator to the first element over the dual dimension of the
Chris@16:      *  given iterator.
Chris@16:      */
Chris@16:     template <typename IteratorT>
Chris@16:     BOOST_UBLAS_INLINE
Chris@16:     typename IteratorT::dual_iterator_type begin(IteratorT const& it)
Chris@16:     {
Chris@16:         return it.begin();
Chris@16:     }
Chris@16: 
Chris@16: }}} // Namespace boost::numeric::ublas
Chris@16: 
Chris@16: 
Chris@16: #endif // BOOST_NUMERIC_UBLAS_OPERATION_BEGIN_HPP