Chris@16: // Copyright 2002 The Trustees of Indiana University.
Chris@16: 
Chris@16: // Use, modification and distribution is subject to the Boost Software 
Chris@16: // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: //  Boost.MultiArray Library
Chris@16: //  Authors: Ronald Garcia
Chris@16: //           Jeremy Siek
Chris@16: //           Andrew Lumsdaine
Chris@16: //  See http://www.boost.org/libs/multi_array for documentation.
Chris@16: 
Chris@16: #ifndef SUBARRAY_RG071801_HPP
Chris@16: #define SUBARRAY_RG071801_HPP
Chris@16: 
Chris@16: //
Chris@16: // subarray.hpp - used to implement standard operator[] on
Chris@16: // multi_arrays
Chris@16: //
Chris@16: 
Chris@16: #include "boost/multi_array/base.hpp"
Chris@16: #include "boost/multi_array/concept_checks.hpp"
Chris@16: #include "boost/limits.hpp"
Chris@16: #include "boost/type.hpp"
Chris@16: #include <algorithm>
Chris@16: #include <cstddef>
Chris@16: #include <functional>
Chris@16: 
Chris@16: namespace boost {
Chris@16: namespace detail {
Chris@16: namespace multi_array {
Chris@16: 
Chris@16: //
Chris@16: // const_sub_array
Chris@16: //    multi_array's proxy class to allow multiple overloads of
Chris@16: //    operator[] in order to provide a clean multi-dimensional array 
Chris@16: //    interface.
Chris@16: template <typename T, std::size_t NumDims, typename TPtr>
Chris@16: class const_sub_array :
Chris@16:   public boost::detail::multi_array::multi_array_impl_base<T,NumDims>
Chris@16: {
Chris@16:   typedef boost::detail::multi_array::multi_array_impl_base<T,NumDims> super_type;
Chris@16: public: 
Chris@16:   typedef typename super_type::value_type value_type;
Chris@16:   typedef typename super_type::const_reference const_reference;
Chris@16:   typedef typename super_type::const_iterator const_iterator;
Chris@16:   typedef typename super_type::const_reverse_iterator const_reverse_iterator;
Chris@16:   typedef typename super_type::element element;
Chris@16:   typedef typename super_type::size_type size_type;
Chris@16:   typedef typename super_type::difference_type difference_type;
Chris@16:   typedef typename super_type::index index;
Chris@16:   typedef typename super_type::extent_range extent_range;
Chris@16: 
Chris@16:   // template typedefs
Chris@16:   template <std::size_t NDims>
Chris@16:   struct const_array_view {
Chris@16:     typedef boost::detail::multi_array::const_multi_array_view<T,NDims> type;
Chris@16:   };
Chris@16: 
Chris@16:   template <std::size_t NDims>
Chris@16:   struct array_view {
Chris@16:     typedef boost::detail::multi_array::multi_array_view<T,NDims> type;
Chris@16:   };
Chris@16: 
Chris@16:   // Allow default copy constructor as well.
Chris@16: 
Chris@16:   template <typename OPtr>
Chris@16:   const_sub_array (const const_sub_array<T,NumDims,OPtr>& rhs) :
Chris@16:     base_(rhs.base_), extents_(rhs.extents_), strides_(rhs.strides_),
Chris@16:     index_base_(rhs.index_base_) {
Chris@16:   }
Chris@16: 
Chris@16:   // const_sub_array always returns const types, regardless of its own
Chris@16:   // constness.
Chris@16:   const_reference operator[](index idx) const {
Chris@16:     return super_type::access(boost::type<const_reference>(),
Chris@16:                               idx,base_,shape(),strides(),index_bases());
Chris@16:   }
Chris@16:   
Chris@16:   template <typename IndexList>
Chris@16:   const element& operator()(const IndexList& indices) const {
Chris@16:     boost::function_requires<
Chris@16:       CollectionConcept<IndexList> >();
Chris@16:     return super_type::access_element(boost::type<const element&>(),
Chris@16:                                       indices,origin(),
Chris@16:                                       shape(),strides(),index_bases());
Chris@16:   }
Chris@16: 
Chris@16:   // see generate_array_view in base.hpp
Chris@16:   template <int NDims>
Chris@16:   typename const_array_view<NDims>::type 
Chris@16:   operator[](const boost::detail::multi_array::
Chris@16:              index_gen<NumDims,NDims>& indices)
Chris@16:     const {
Chris@16:     typedef typename const_array_view<NDims>::type return_type;
Chris@16:     return
Chris@16:       super_type::generate_array_view(boost::type<return_type>(),
Chris@16:                                       indices,
Chris@16:                                       shape(),
Chris@16:                                       strides(),
Chris@16:                                       index_bases(),
Chris@16:                                       base_);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename OPtr>
Chris@16:   bool operator<(const const_sub_array<T,NumDims,OPtr>& rhs) const {
Chris@16:     return std::lexicographical_compare(begin(),end(),rhs.begin(),rhs.end());
Chris@16:   }
Chris@16: 
Chris@16:   template <typename OPtr>
Chris@16:   bool operator==(const const_sub_array<T,NumDims,OPtr>& rhs) const {
Chris@16:     if(std::equal(shape(),shape()+num_dimensions(),rhs.shape()))
Chris@16:       return std::equal(begin(),end(),rhs.begin());
Chris@16:     else return false;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename OPtr>
Chris@16:   bool operator!=(const const_sub_array<T,NumDims,OPtr>& rhs) const {
Chris@16:     return !(*this == rhs);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename OPtr>
Chris@16:   bool operator>(const const_sub_array<T,NumDims,OPtr>& rhs) const {
Chris@16:     return rhs < *this;
Chris@16:   }
Chris@16: 
Chris@16:   template <typename OPtr>
Chris@16:   bool operator<=(const const_sub_array<T,NumDims,OPtr>& rhs) const {
Chris@16:     return !(*this > rhs);
Chris@16:   }
Chris@16: 
Chris@16:   template <typename OPtr>
Chris@16:   bool operator>=(const const_sub_array<T,NumDims,OPtr>& rhs) const {
Chris@16:     return !(*this < rhs);
Chris@16:   }
Chris@16: 
Chris@16:   const_iterator begin() const {
Chris@16:     return const_iterator(*index_bases(),origin(),
Chris@16:                           shape(),strides(),index_bases());
Chris@16:   }
Chris@16: 
Chris@16:   const_iterator end() const {
Chris@16:     return const_iterator(*index_bases()+(index)*shape(),origin(),
Chris@16:                           shape(),strides(),index_bases());
Chris@16:   }
Chris@16: 
Chris@16:   const_reverse_iterator rbegin() const {
Chris@16:     return const_reverse_iterator(end());
Chris@16:   }
Chris@16: 
Chris@16:   const_reverse_iterator rend() const {
Chris@16:     return const_reverse_iterator(begin());
Chris@16:   }
Chris@16: 
Chris@16:   TPtr origin() const { return base_; }
Chris@16:   size_type size() const { return extents_[0]; }
Chris@16:   size_type max_size() const { return num_elements(); }
Chris@16:   bool empty() const { return size() == 0; }
Chris@16:   size_type num_dimensions() const { return NumDims; }
Chris@16:   const size_type*  shape() const { return extents_; }
Chris@16:   const index* strides() const { return strides_; }
Chris@16:   const index* index_bases() const { return index_base_; }
Chris@16: 
Chris@16:   size_type num_elements() const { 
Chris@16:     return std::accumulate(shape(),shape() + num_dimensions(),
Chris@16:                            size_type(1), std::multiplies<size_type>());
Chris@16:   }
Chris@16: 
Chris@16: 
Chris@16: #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
Chris@16: protected:
Chris@16:   template <typename,std::size_t> friend class value_accessor_n;  
Chris@16:   template <typename,std::size_t,typename> friend class const_sub_array;
Chris@16: #else    
Chris@16: public:  // Should be protected
Chris@16: #endif
Chris@16: 
Chris@16:   const_sub_array (TPtr base,
Chris@16:                  const size_type* extents,
Chris@16:                  const index* strides,
Chris@16:                  const index* index_base) :
Chris@16:     base_(base), extents_(extents), strides_(strides),
Chris@16:     index_base_(index_base) {
Chris@16:   }
Chris@16: 
Chris@16:   TPtr base_;
Chris@16:   const size_type* extents_;
Chris@16:   const index* strides_;
Chris@16:   const index* index_base_;
Chris@16: private:
Chris@16:   // const_sub_array cannot be assigned to (no deep copies!)
Chris@16:   const_sub_array& operator=(const const_sub_array&);
Chris@16: };
Chris@16: 
Chris@16: 
Chris@16: //
Chris@16: // sub_array
Chris@16: //    multi_array's proxy class to allow multiple overloads of
Chris@16: //    operator[] in order to provide a clean multi-dimensional array 
Chris@16: //    interface.
Chris@16: template <typename T, std::size_t NumDims>
Chris@16: class sub_array : public const_sub_array<T,NumDims,T*>
Chris@16: {
Chris@16:   typedef const_sub_array<T,NumDims,T*> super_type;
Chris@16: public: 
Chris@16:   typedef typename super_type::element element;
Chris@16:   typedef typename super_type::reference reference;
Chris@16:   typedef typename super_type::index index;
Chris@16:   typedef typename super_type::size_type size_type;
Chris@16:   typedef typename super_type::iterator iterator;
Chris@16:   typedef typename super_type::reverse_iterator reverse_iterator;
Chris@16:   typedef typename super_type::const_reference const_reference;
Chris@16:   typedef typename super_type::const_iterator const_iterator;
Chris@16:   typedef typename super_type::const_reverse_iterator const_reverse_iterator;
Chris@16: 
Chris@16:   // template typedefs
Chris@16:   template <std::size_t NDims>
Chris@16:   struct const_array_view {
Chris@16:     typedef boost::detail::multi_array::const_multi_array_view<T,NDims> type;
Chris@16:   };
Chris@16: 
Chris@16:   template <std::size_t NDims>
Chris@16:   struct array_view {
Chris@16:     typedef boost::detail::multi_array::multi_array_view<T,NDims> type;
Chris@16:   };
Chris@16: 
Chris@16:   // Assignment from other ConstMultiArray types.
Chris@16:   template <typename ConstMultiArray>
Chris@16:   sub_array& operator=(const ConstMultiArray& other) {
Chris@16:     function_requires< boost::multi_array_concepts::ConstMultiArrayConcept< 
Chris@16:         ConstMultiArray, NumDims> >();
Chris@16: 
Chris@16:     // make sure the dimensions agree
Chris@16:     BOOST_ASSERT(other.num_dimensions() == this->num_dimensions());
Chris@16:     BOOST_ASSERT(std::equal(other.shape(),other.shape()+this->num_dimensions(),
Chris@16:                             this->shape()));
Chris@16:     // iterator-based copy
Chris@16:     std::copy(other.begin(),other.end(),begin());
Chris@16:     return *this;
Chris@16:   }
Chris@16: 
Chris@16: 
Chris@16:   sub_array& operator=(const sub_array& other) {
Chris@16:     if (&other != this) {
Chris@16:       // make sure the dimensions agree
Chris@16:       BOOST_ASSERT(other.num_dimensions() == this->num_dimensions());
Chris@16:       BOOST_ASSERT(std::equal(other.shape(),
Chris@16:                               other.shape()+this->num_dimensions(),
Chris@16:                               this->shape()));
Chris@16:       // iterator-based copy
Chris@16:       std::copy(other.begin(),other.end(),begin());
Chris@16:     }
Chris@16:     return *this;
Chris@16:   }
Chris@16: 
Chris@16:   T* origin() { return this->base_; }
Chris@16:   const T* origin() const { return this->base_; }
Chris@16: 
Chris@16:   reference operator[](index idx) {
Chris@16:     return super_type::access(boost::type<reference>(),
Chris@16:                               idx,this->base_,this->shape(),this->strides(),
Chris@16:                               this->index_bases());
Chris@16:   }
Chris@16: 
Chris@16:   // see generate_array_view in base.hpp
Chris@16:   template <int NDims>
Chris@16:   typename array_view<NDims>::type 
Chris@16:   operator[](const boost::detail::multi_array::
Chris@16:              index_gen<NumDims,NDims>& indices) {
Chris@16:     typedef typename array_view<NDims>::type return_type;
Chris@16:     return
Chris@16:       super_type::generate_array_view(boost::type<return_type>(),
Chris@16:                                       indices,
Chris@16:                                       this->shape(),
Chris@16:                                       this->strides(),
Chris@16:                                       this->index_bases(),
Chris@16:                                       origin());
Chris@16:   }
Chris@16: 
Chris@16:   template <class IndexList>
Chris@16:   element& operator()(const IndexList& indices) {
Chris@16:     boost::function_requires<
Chris@16:       CollectionConcept<IndexList> >();
Chris@16:     return super_type::access_element(boost::type<element&>(),
Chris@16:                                       indices,origin(),
Chris@16:                                       this->shape(),this->strides(),
Chris@16:                                       this->index_bases());
Chris@16:   }
Chris@16: 
Chris@16:   iterator begin() {
Chris@16:     return iterator(*this->index_bases(),origin(),
Chris@16:                     this->shape(),this->strides(),this->index_bases());
Chris@16:   }
Chris@16: 
Chris@16:   iterator end() {
Chris@16:     return iterator(*this->index_bases()+(index)*this->shape(),origin(),
Chris@16:                     this->shape(),this->strides(),this->index_bases());
Chris@16:   }
Chris@16: 
Chris@16:   // RG - rbegin() and rend() written naively to thwart MSVC ICE.
Chris@16:   reverse_iterator rbegin() {
Chris@16:     reverse_iterator ri(end());
Chris@16:     return ri;
Chris@16:   }
Chris@16: 
Chris@16:   reverse_iterator rend() {
Chris@16:     reverse_iterator ri(begin());
Chris@16:     return ri;
Chris@16:   }
Chris@16: 
Chris@16:   //
Chris@16:   // proxies
Chris@16:   //
Chris@16: 
Chris@16:   template <class IndexList>
Chris@16:   const element& operator()(const IndexList& indices) const {
Chris@16:     boost::function_requires<
Chris@16:       CollectionConcept<IndexList> >();
Chris@16:     return super_type::operator()(indices);
Chris@16:   }
Chris@16: 
Chris@16:   const_reference operator[](index idx) const {
Chris@16:     return super_type::operator[](idx);
Chris@16:   }
Chris@16: 
Chris@16:   // see generate_array_view in base.hpp
Chris@16:   template <int NDims>
Chris@16:   typename const_array_view<NDims>::type 
Chris@16:   operator[](const boost::detail::multi_array::
Chris@16:              index_gen<NumDims,NDims>& indices)
Chris@16:     const {
Chris@16:     return super_type::operator[](indices);
Chris@16:   }
Chris@16: 
Chris@16:   const_iterator begin() const {
Chris@16:     return super_type::begin();
Chris@16:   }
Chris@16:   
Chris@16:   const_iterator end() const {
Chris@16:     return super_type::end();
Chris@16:   }
Chris@16: 
Chris@16:   const_reverse_iterator rbegin() const {
Chris@16:     return super_type::rbegin();
Chris@16:   }
Chris@16: 
Chris@16:   const_reverse_iterator rend() const {
Chris@16:     return super_type::rend();
Chris@16:   }
Chris@16: 
Chris@16: #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
Chris@16: private:
Chris@16:   template <typename,std::size_t> friend class value_accessor_n;
Chris@16: #else
Chris@16: public: // should be private
Chris@16: #endif
Chris@16: 
Chris@16:   sub_array (T* base,
Chris@16:             const size_type* extents,
Chris@16:             const index* strides,
Chris@16:             const index* index_base) :
Chris@16:     super_type(base,extents,strides,index_base) {
Chris@16:   }
Chris@16: 
Chris@16: };
Chris@16: 
Chris@16: } // namespace multi_array
Chris@16: } // namespace detail
Chris@16: //
Chris@16: // traits classes to get sub_array types
Chris@16: //
Chris@16: template <typename Array, int N>
Chris@16: class subarray_gen {
Chris@16:   typedef typename Array::element element;
Chris@16: public:
Chris@16:   typedef boost::detail::multi_array::sub_array<element,N> type;
Chris@16: };
Chris@16: 
Chris@16: template <typename Array, int N>
Chris@16: class const_subarray_gen {
Chris@16:   typedef typename Array::element element;
Chris@16: public:
Chris@16:   typedef boost::detail::multi_array::const_sub_array<element,N> type;  
Chris@16: };
Chris@16: } // namespace boost
Chris@16:   
Chris@16: #endif // SUBARRAY_RG071801_HPP