williamr@2: // Copyright 2002 The Trustees of Indiana University.
williamr@2: 
williamr@2: // Use, modification and distribution is subject to the Boost Software 
williamr@2: // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
williamr@2: // http://www.boost.org/LICENSE_1_0.txt)
williamr@2: 
williamr@2: //  Boost.MultiArray Library
williamr@2: //  Authors: Ronald Garcia
williamr@2: //           Jeremy Siek
williamr@2: //           Andrew Lumsdaine
williamr@2: //  See http://www.boost.org/libs/multi_array for documentation.
williamr@2: 
williamr@2: #ifndef BOOST_MULTI_ARRAY_VIEW_RG071301_HPP
williamr@2: #define BOOST_MULTI_ARRAY_VIEW_RG071301_HPP
williamr@2: 
williamr@2: //
williamr@2: // view.hpp - code for creating "views" of array data.
williamr@2: //
williamr@2: 
williamr@2: #include "boost/multi_array/base.hpp"
williamr@2: #include "boost/multi_array/concept_checks.hpp"
williamr@2: #include "boost/multi_array/iterator.hpp"
williamr@2: #include "boost/multi_array/storage_order.hpp"
williamr@2: #include "boost/multi_array/subarray.hpp"
williamr@2: #include "boost/multi_array/algorithm.hpp"
williamr@2: #include "boost/type_traits/is_integral.hpp"
williamr@2: #include "boost/array.hpp"
williamr@2: #include "boost/limits.hpp"
williamr@2: #include <algorithm>
williamr@2: #include <cstddef>
williamr@2: #include <functional>
williamr@2: #include <numeric>
williamr@2: 
williamr@2: namespace boost {
williamr@2: namespace detail {
williamr@2: namespace multi_array {
williamr@2: 
williamr@2: // TPtr = const T* defaulted in base.hpp
williamr@2: template <typename T, std::size_t NumDims, typename TPtr>
williamr@2: class const_multi_array_view :
williamr@2:     public boost::detail::multi_array::multi_array_impl_base<T,NumDims>
williamr@2: {
williamr@2:   typedef boost::detail::multi_array::multi_array_impl_base<T,NumDims> super_type;
williamr@2: public: 
williamr@2:   typedef typename super_type::value_type value_type;
williamr@2:   typedef typename super_type::const_reference const_reference;
williamr@2:   typedef typename super_type::const_iterator const_iterator;
williamr@2:   typedef typename super_type::const_reverse_iterator const_reverse_iterator;
williamr@2:   typedef typename super_type::element element;
williamr@2:   typedef typename super_type::size_type size_type;
williamr@2:   typedef typename super_type::difference_type difference_type;
williamr@2:   typedef typename super_type::index index;
williamr@2:   typedef typename super_type::extent_range extent_range;
williamr@2: 
williamr@2:   // template typedefs
williamr@2:   template <std::size_t NDims>
williamr@2:   struct const_array_view {
williamr@2:     typedef boost::detail::multi_array::const_multi_array_view<T,NDims> type;
williamr@2:   };
williamr@2: 
williamr@2:   template <std::size_t NDims>
williamr@2:   struct array_view {
williamr@2:     typedef boost::detail::multi_array::multi_array_view<T,NDims> type;
williamr@2:   };
williamr@2: 
williamr@2:   template <typename OPtr>
williamr@2:   const_multi_array_view(const 
williamr@2:                          const_multi_array_view<T,NumDims,OPtr>& other) :
williamr@2:     base_(other.base_), origin_offset_(other.origin_offset_),
williamr@2:     num_elements_(other.num_elements_), extent_list_(other.extent_list_),
williamr@2:     stride_list_(other.stride_list_), index_base_list_(other.index_base_list_)
williamr@2:   { }
williamr@2: 
williamr@2: 
williamr@2:   template <class BaseList>
williamr@2: #ifdef BOOST_NO_SFINAE
williamr@2:   void
williamr@2: #else
williamr@2:   typename
williamr@2:   disable_if<typename boost::is_integral<BaseList>::type,void >::type
williamr@2: #endif
williamr@2:   reindex(const BaseList& values) {
williamr@2:     boost::function_requires<
williamr@2:       detail::multi_array::CollectionConcept<BaseList> >();
williamr@2:     boost::detail::multi_array::
williamr@2:       copy_n(values.begin(),num_dimensions(),index_base_list_.begin());
williamr@2:     origin_offset_ =
williamr@2:       this->calculate_indexing_offset(stride_list_,index_base_list_);
williamr@2:   }
williamr@2: 
williamr@2:   void reindex(index value) {
williamr@2:     index_base_list_.assign(value);
williamr@2:     origin_offset_ =
williamr@2:       this->calculate_indexing_offset(stride_list_,index_base_list_);
williamr@2:   }
williamr@2: 
williamr@2:   size_type num_dimensions() const { return NumDims; }
williamr@2: 
williamr@2:   size_type size() const { return extent_list_.front(); }
williamr@2:   size_type max_size() const { return num_elements(); }
williamr@2:   bool empty() const { return size() == 0; }
williamr@2: 
williamr@2:   const size_type* shape() const {
williamr@2:     return extent_list_.data();
williamr@2:   }
williamr@2: 
williamr@2:   const index* strides() const {
williamr@2:     return stride_list_.data();
williamr@2:   }
williamr@2: 
williamr@2:   const T* origin() const { return base_+origin_offset_; }
williamr@2: 
williamr@2:   size_type num_elements() const { return num_elements_; }
williamr@2: 
williamr@2:   const index* index_bases() const {
williamr@2:     return index_base_list_.data();
williamr@2:   }
williamr@2: 
williamr@2:   template <typename IndexList>
williamr@2:   const element& operator()(IndexList indices) const {
williamr@2:     boost::function_requires<
williamr@2:       detail::multi_array::CollectionConcept<IndexList> >();
williamr@2:     return super_type::access_element(boost::type<const element&>(),
williamr@2:                                       indices,origin(),
williamr@2:                                       shape(),strides(),index_bases());
williamr@2:   }
williamr@2: 
williamr@2:   // Only allow const element access
williamr@2:   const_reference operator[](index idx) const {
williamr@2:     return super_type::access(boost::type<const_reference>(),
williamr@2:                               idx,origin(),
williamr@2:                               shape(),strides(),
williamr@2:                               index_bases());
williamr@2:   }
williamr@2: 
williamr@2:   // see generate_array_view in base.hpp
williamr@2: #if !defined(BOOST_MSVC) || BOOST_MSVC > 1300
williamr@2:   template <int NDims>
williamr@2: #else
williamr@2:   template <int NumDims, int NDims> // else ICE
williamr@2: #endif // BOOST_MSVC
williamr@2:   typename const_array_view<NDims>::type 
williamr@2:   operator[](const boost::detail::multi_array::
williamr@2:              index_gen<NumDims,NDims>& indices)
williamr@2:     const {
williamr@2:     typedef typename const_array_view<NDims>::type return_type;
williamr@2:     return
williamr@2:       super_type::generate_array_view(boost::type<return_type>(),
williamr@2:                                       indices,
williamr@2:                                       shape(),
williamr@2:                                       strides(),
williamr@2:                                       index_bases(),
williamr@2:                                       origin());
williamr@2:   }
williamr@2:   const_iterator begin() const {
williamr@2:     return const_iterator(*index_bases(),origin(),
williamr@2:                           shape(),strides(),index_bases());
williamr@2:   }
williamr@2: 
williamr@2:   const_iterator end() const {
williamr@2:     return const_iterator(*index_bases()+(index)*shape(),origin(),
williamr@2:                           shape(),strides(),index_bases());
williamr@2:   }
williamr@2:   
williamr@2:   const_reverse_iterator rbegin() const {
williamr@2:     return const_reverse_iterator(end());
williamr@2:   }
williamr@2: 
williamr@2:   const_reverse_iterator rend() const {
williamr@2:     return const_reverse_iterator(begin());
williamr@2:   }
williamr@2: 
williamr@2: 
williamr@2:   template <typename OPtr>
williamr@2:   bool operator==(const
williamr@2:                   const_multi_array_view<T,NumDims,OPtr>& rhs)
williamr@2:     const {
williamr@2:     if(std::equal(extent_list_.begin(),
williamr@2:                   extent_list_.end(),
williamr@2:                   rhs.extent_list_.begin()))
williamr@2:       return std::equal(begin(),end(),rhs.begin());
williamr@2:     else return false;
williamr@2:   }
williamr@2: 
williamr@2:   template <typename OPtr>
williamr@2:   bool operator<(const
williamr@2:                  const_multi_array_view<T,NumDims,OPtr>& rhs)
williamr@2:     const {
williamr@2:     return std::lexicographical_compare(begin(),end(),rhs.begin(),rhs.end());
williamr@2:   }
williamr@2: 
williamr@2:   template <typename OPtr>
williamr@2:   bool operator!=(const
williamr@2:                   const_multi_array_view<T,NumDims,OPtr>& rhs)
williamr@2:     const {
williamr@2:     return !(*this == rhs);
williamr@2:   }
williamr@2: 
williamr@2:   template <typename OPtr>
williamr@2:   bool operator>(const
williamr@2:                  const_multi_array_view<T,NumDims,OPtr>& rhs)
williamr@2:     const {
williamr@2:     return rhs < *this;
williamr@2:   }
williamr@2: 
williamr@2:   template <typename OPtr>
williamr@2:   bool operator<=(const
williamr@2:                  const_multi_array_view<T,NumDims,OPtr>& rhs)
williamr@2:     const {
williamr@2:     return !(*this > rhs);
williamr@2:   }
williamr@2: 
williamr@2:   template <typename OPtr>
williamr@2:   bool operator>=(const
williamr@2:                  const_multi_array_view<T,NumDims,OPtr>& rhs)
williamr@2:     const {
williamr@2:     return !(*this < rhs);
williamr@2:   }
williamr@2: 
williamr@2: 
williamr@2: #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
williamr@2: protected:
williamr@2:   template <typename,std::size_t> friend class multi_array_impl_base;
williamr@2:   template <typename,std::size_t,typename> friend class const_multi_array_view;
williamr@2: #else
williamr@2: public: // should be protected
williamr@2: #endif
williamr@2: 
williamr@2:   // This constructor is used by multi_array_impl_base::generate_array_view
williamr@2:   // to create strides  
williamr@2:   template <typename ExtentList, typename Index>
williamr@2:   explicit const_multi_array_view(TPtr base,
williamr@2:                            const ExtentList& extents,
williamr@2:                            const boost::array<Index,NumDims>& strides): 
williamr@2:     base_(base), origin_offset_(0) {
williamr@2: 
williamr@2:     index_base_list_.assign(0);
williamr@2: 
williamr@2:     // Get the extents and strides
williamr@2:     boost::detail::multi_array::
williamr@2:       copy_n(extents.begin(),NumDims,extent_list_.begin());
williamr@2:     boost::detail::multi_array::
williamr@2:       copy_n(strides.begin(),NumDims,stride_list_.begin());
williamr@2: 
williamr@2:     // Calculate the array size
williamr@2:     num_elements_ = std::accumulate(extent_list_.begin(),extent_list_.end(),
williamr@2:                             size_type(1),std::multiplies<size_type>());
williamr@2: #if 0
williamr@2:     assert(num_elements_ != 0);
williamr@2: #endif
williamr@2:   }
williamr@2: 
williamr@2:   typedef boost::array<size_type,NumDims> size_list;
williamr@2:   typedef boost::array<index,NumDims> index_list;
williamr@2: 
williamr@2:   TPtr base_;
williamr@2:   index origin_offset_;
williamr@2:   size_type num_elements_;
williamr@2:   size_list extent_list_;
williamr@2:   index_list stride_list_;
williamr@2:   index_list index_base_list_;
williamr@2: 
williamr@2: private:
williamr@2:   // const_multi_array_view cannot be assigned to (no deep copies!)
williamr@2:   const_multi_array_view& operator=(const const_multi_array_view& other);
williamr@2: };
williamr@2: 
williamr@2: 
williamr@2: template <typename T, std::size_t NumDims>
williamr@2: class multi_array_view :
williamr@2:   public const_multi_array_view<T,NumDims,T*>
williamr@2: {
williamr@2:   typedef const_multi_array_view<T,NumDims,T*> super_type;
williamr@2: public: 
williamr@2:   typedef typename super_type::value_type value_type;
williamr@2:   typedef typename super_type::reference reference;
williamr@2:   typedef typename super_type::iterator iterator;
williamr@2:   typedef typename super_type::reverse_iterator reverse_iterator;
williamr@2:   typedef typename super_type::const_reference const_reference;
williamr@2:   typedef typename super_type::const_iterator const_iterator;
williamr@2:   typedef typename super_type::const_reverse_iterator const_reverse_iterator;
williamr@2:   typedef typename super_type::element element;
williamr@2:   typedef typename super_type::size_type size_type;
williamr@2:   typedef typename super_type::difference_type difference_type;
williamr@2:   typedef typename super_type::index index;
williamr@2:   typedef typename super_type::extent_range extent_range;
williamr@2: 
williamr@2:   // template typedefs
williamr@2:   template <std::size_t NDims>
williamr@2:   struct const_array_view {
williamr@2:     typedef boost::detail::multi_array::const_multi_array_view<T,NDims> type;
williamr@2:   };
williamr@2: 
williamr@2:   template <std::size_t NDims>
williamr@2:   struct array_view {
williamr@2:     typedef boost::detail::multi_array::multi_array_view<T,NDims> type;
williamr@2:   };
williamr@2: 
williamr@2:   // Assignment from other ConstMultiArray types.
williamr@2:   template <typename ConstMultiArray>
williamr@2:   multi_array_view& operator=(const ConstMultiArray& other) {
williamr@2:     function_requires< 
williamr@2:       boost::detail::multi_array::
williamr@2:       ConstMultiArrayConcept<ConstMultiArray,NumDims> >();
williamr@2: 
williamr@2:     // make sure the dimensions agree
williamr@2:     assert(other.num_dimensions() == this->num_dimensions());
williamr@2:     assert(std::equal(other.shape(),other.shape()+this->num_dimensions(),
williamr@2:                       this->shape()));
williamr@2:     // iterator-based copy
williamr@2:     std::copy(other.begin(),other.end(),begin());
williamr@2:     return *this;
williamr@2:   }
williamr@2: 
williamr@2: 
williamr@2:   multi_array_view& operator=(const multi_array_view& other) {
williamr@2:     if (&other != this) {
williamr@2:       // make sure the dimensions agree
williamr@2:       assert(other.num_dimensions() == this->num_dimensions());
williamr@2:       assert(std::equal(other.shape(),other.shape()+this->num_dimensions(),
williamr@2:                         this->shape()));
williamr@2:       // iterator-based copy
williamr@2:       std::copy(other.begin(),other.end(),begin());
williamr@2:     }
williamr@2:     return *this;
williamr@2:   }
williamr@2: 
williamr@2:   element* origin() { return this->base_+this->origin_offset_; }
williamr@2: 
williamr@2:   template <class IndexList>
williamr@2:   element& operator()(const IndexList& indices) {
williamr@2:     boost::function_requires<
williamr@2:       detail::multi_array::CollectionConcept<IndexList> >();
williamr@2:     return super_type::access_element(boost::type<element&>(),
williamr@2:                                       indices,origin(),
williamr@2:                                       this->shape(),this->strides(),
williamr@2:                                       this->index_bases());
williamr@2:   }
williamr@2: 
williamr@2: 
williamr@2:   reference operator[](index idx) {
williamr@2:     return super_type::access(boost::type<reference>(),
williamr@2:                               idx,origin(),
williamr@2:                               this->shape(),this->strides(),
williamr@2:                               this->index_bases());
williamr@2:   }
williamr@2: 
williamr@2: 
williamr@2:   // see generate_array_view in base.hpp
williamr@2: #if !defined(BOOST_MSVC) || BOOST_MSVC > 1300
williamr@2:   template <int NDims>
williamr@2: #else
williamr@2:   template <int NumDims, int NDims> // else ICE
williamr@2: #endif // BOOST_MSVC
williamr@2:   typename array_view<NDims>::type 
williamr@2:   operator[](const boost::detail::multi_array::
williamr@2:              index_gen<NumDims,NDims>& indices) {
williamr@2:     typedef typename array_view<NDims>::type return_type;
williamr@2:     return
williamr@2:       super_type::generate_array_view(boost::type<return_type>(),
williamr@2:                                       indices,
williamr@2:                                       this->shape(),
williamr@2:                                       this->strides(),
williamr@2:                                       this->index_bases(),
williamr@2:                                       origin());
williamr@2:   }
williamr@2:   
williamr@2:   
williamr@2:   iterator begin() {
williamr@2:     return iterator(*this->index_bases(),origin(),
williamr@2:                     this->shape(),this->strides(),
williamr@2:                     this->index_bases());
williamr@2:   }
williamr@2: 
williamr@2:   iterator end() {
williamr@2:     return iterator(*this->index_bases()+(index)*this->shape(),origin(),
williamr@2:                     this->shape(),this->strides(),
williamr@2:                     this->index_bases());
williamr@2:   }
williamr@2: 
williamr@2:   reverse_iterator rbegin() {
williamr@2:     return reverse_iterator(end());
williamr@2:   }
williamr@2: 
williamr@2:   reverse_iterator rend() {
williamr@2:     return reverse_iterator(begin());
williamr@2:   }
williamr@2: 
williamr@2:   // Using declarations don't seem to work for g++
williamr@2:   // These are the proxies to work around this.
williamr@2: 
williamr@2:   const element* origin() const { return super_type::origin(); }
williamr@2: 
williamr@2:   template <class IndexList>
williamr@2:   const element& operator()(const IndexList& indices) const {
williamr@2:     boost::function_requires<
williamr@2:       detail::multi_array::CollectionConcept<IndexList> >();
williamr@2:     return super_type::operator()(indices);
williamr@2:   }
williamr@2: 
williamr@2:   const_reference operator[](index idx) const {
williamr@2:     return super_type::operator[](idx);
williamr@2:   }
williamr@2: 
williamr@2:   // see generate_array_view in base.hpp
williamr@2: #if !defined(BOOST_MSVC) || BOOST_MSVC > 1300
williamr@2:   template <int NDims>
williamr@2: #else
williamr@2:   template <int NumDims, int NDims> // else ICE
williamr@2: #endif // BOOST_MSVC
williamr@2:   typename const_array_view<NDims>::type 
williamr@2:   operator[](const boost::detail::multi_array::
williamr@2:              index_gen<NumDims,NDims>& indices)
williamr@2:     const {
williamr@2:     return super_type::operator[](indices);
williamr@2:   }
williamr@2:   
williamr@2:   const_iterator begin() const {
williamr@2:     return super_type::begin();
williamr@2:   }
williamr@2: 
williamr@2:   const_iterator end() const {
williamr@2:     return super_type::end();
williamr@2:   }
williamr@2: 
williamr@2:   const_reverse_iterator rbegin() const {
williamr@2:     return super_type::rbegin();
williamr@2:   }
williamr@2: 
williamr@2:   const_reverse_iterator rend() const {
williamr@2:     return super_type::rend();
williamr@2:   }
williamr@2: 
williamr@2: #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
williamr@2: private:
williamr@2:   template <typename,std::size_t> friend class multi_array_impl_base;
williamr@2: #else
williamr@2: public: // should be private
williamr@2: #endif
williamr@2: 
williamr@2:   // constructor used by multi_array_impl_base::generate_array_view to
williamr@2:   // generate array views
williamr@2:   template <typename ExtentList, typename Index>
williamr@2:   explicit multi_array_view(T* base,
williamr@2:                             const ExtentList& extents,
williamr@2:                             const boost::array<Index,NumDims>& strides) :
williamr@2:     super_type(base,extents,strides) { }
williamr@2: 
williamr@2: };
williamr@2: 
williamr@2: } // namespace multi_array
williamr@2: } // namespace detail
williamr@2: 
williamr@2: //
williamr@2: // traits classes to get array_view types
williamr@2: //
williamr@2: template <typename Array, int N>
williamr@2: class array_view_gen {
williamr@2:   typedef typename Array::element element;
williamr@2: public:
williamr@2:   typedef boost::detail::multi_array::multi_array_view<element,N> type;
williamr@2: };
williamr@2: 
williamr@2: template <typename Array, int N>
williamr@2: class const_array_view_gen {
williamr@2:   typedef typename Array::element element;
williamr@2: public:
williamr@2:   typedef boost::detail::multi_array::const_multi_array_view<element,N> type;  
williamr@2: };
williamr@2: 
williamr@2: } // namespace boost
williamr@2: 
williamr@2: #endif // BOOST_MULTI_ARRAY_VIEW_RG071301_HPP
williamr@2: