1 // Copyright 2002 The Trustees of Indiana University.
3 // Use, modification and distribution is subject to the Boost Software
4 // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
5 // http://www.boost.org/LICENSE_1_0.txt)
7 // Boost.MultiArray Library
8 // Authors: Ronald Garcia
11 // See http://www.boost.org/libs/multi_array for documentation.
13 #ifndef BOOST_MULTI_ARRAY_VIEW_RG071301_HPP
14 #define BOOST_MULTI_ARRAY_VIEW_RG071301_HPP
17 // view.hpp - code for creating "views" of array data.
20 #include "boost/multi_array/base.hpp"
21 #include "boost/multi_array/concept_checks.hpp"
22 #include "boost/multi_array/iterator.hpp"
23 #include "boost/multi_array/storage_order.hpp"
24 #include "boost/multi_array/subarray.hpp"
25 #include "boost/multi_array/algorithm.hpp"
26 #include "boost/array.hpp"
27 #include "boost/limits.hpp"
35 namespace multi_array {
37 // TPtr = const T* defaulted in base.hpp
38 template <typename T, std::size_t NumDims, typename TPtr>
39 class const_multi_array_view :
40 public boost::detail::multi_array::multi_array_impl_base<T,NumDims>
42 typedef boost::detail::multi_array::multi_array_impl_base<T,NumDims> super_type;
44 typedef typename super_type::value_type value_type;
45 typedef typename super_type::const_reference const_reference;
46 typedef typename super_type::const_iterator const_iterator;
47 typedef typename super_type::const_reverse_iterator const_reverse_iterator;
48 typedef typename super_type::element element;
49 typedef typename super_type::size_type size_type;
50 typedef typename super_type::difference_type difference_type;
51 typedef typename super_type::index index;
52 typedef typename super_type::extent_range extent_range;
55 template <std::size_t NDims>
56 struct const_array_view {
57 typedef boost::detail::multi_array::const_multi_array_view<T,NDims> type;
60 template <std::size_t NDims>
62 typedef boost::detail::multi_array::multi_array_view<T,NDims> type;
65 template <typename OPtr>
66 const_multi_array_view(const
67 const_multi_array_view<T,NumDims,OPtr>& other) :
68 base_(other.base_), origin_offset_(other.origin_offset_),
69 num_elements_(other.num_elements_), extent_list_(other.extent_list_),
70 stride_list_(other.stride_list_), index_base_list_(other.index_base_list_)
74 template <class BaseList>
75 void reindex(const BaseList& values) {
76 boost::copy_n(values.begin(),num_dimensions(),index_base_list_.begin());
78 this->calculate_indexing_offset(stride_list_,index_base_list_);
81 void reindex(index value) {
82 index_base_list_.assign(value);
84 this->calculate_indexing_offset(stride_list_,index_base_list_);
87 size_type num_dimensions() const { return NumDims; }
89 size_type size() const { return extent_list_.front(); }
90 size_type max_size() const { return num_elements(); }
91 bool empty() const { return size() == 0; }
93 const size_type* shape() const {
94 return extent_list_.data();
97 const index* strides() const {
98 return stride_list_.data();
101 const T* origin() const { return base_+origin_offset_; }
103 size_type num_elements() const { return num_elements_; }
105 const index* index_bases() const {
106 return index_base_list_.data();
109 template <typename IndexList>
110 const element& operator()(IndexList indices) const {
111 return super_type::access_element(boost::type<const element&>(),
116 // Only allow const element access
117 const_reference operator[](index idx) const {
118 return super_type::access(boost::type<const_reference>(),
124 // see generate_array_view in base.hpp
125 #if !defined(BOOST_MSVC) || BOOST_MSVC > 1300
128 template <int NumDims, int NDims> // else ICE
130 typename const_array_view<NDims>::type
131 operator[](const boost::detail::multi_array::
132 index_gen<NumDims,NDims>& indices)
134 typedef typename const_array_view<NDims>::type return_type;
136 super_type::generate_array_view(boost::type<return_type>(),
143 const_iterator begin() const {
144 return const_iterator(*index_bases(),origin(),
145 shape(),strides(),index_bases());
148 const_iterator end() const {
149 return const_iterator(*index_bases()+*shape(),origin(),
150 shape(),strides(),index_bases());
153 const_reverse_iterator rbegin() const {
154 return const_reverse_iterator(end());
157 const_reverse_iterator rend() const {
158 return const_reverse_iterator(begin());
162 template <typename OPtr>
163 bool operator==(const
164 const_multi_array_view<T,NumDims,OPtr>& rhs)
166 if(std::equal(extent_list_.begin(),
168 rhs.extent_list_.begin()))
169 return std::equal(begin(),end(),rhs.begin());
173 template <typename OPtr>
175 const_multi_array_view<T,NumDims,OPtr>& rhs)
177 return std::lexicographical_compare(begin(),end(),rhs.begin(),rhs.end());
180 template <typename OPtr>
181 bool operator!=(const
182 const_multi_array_view<T,NumDims,OPtr>& rhs)
184 return !(*this == rhs);
187 template <typename OPtr>
189 const_multi_array_view<T,NumDims,OPtr>& rhs)
194 template <typename OPtr>
195 bool operator<=(const
196 const_multi_array_view<T,NumDims,OPtr>& rhs)
198 return !(*this > rhs);
201 template <typename OPtr>
202 bool operator>=(const
203 const_multi_array_view<T,NumDims,OPtr>& rhs)
205 return !(*this < rhs);
209 #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
211 template <typename,std::size_t> friend class multi_array_impl_base;
212 template <typename,std::size_t,typename> friend class const_multi_array_view;
214 public: // should be protected
217 // This constructor is used by multi_array_impl_base::generate_array_view
219 template <typename ExtentList, typename Index>
220 explicit const_multi_array_view(TPtr base,
221 const ExtentList& extents,
222 const boost::array<Index,NumDims>& strides):
223 base_(base), origin_offset_(0) {
225 index_base_list_.assign(0);
227 // Get the extents and strides
228 boost::copy_n(extents.begin(),NumDims,extent_list_.begin());
229 boost::copy_n(strides.begin(),NumDims,stride_list_.begin());
231 // Calculate the array size
232 num_elements_ = std::accumulate(extent_list_.begin(),extent_list_.end(),
233 size_type(1),std::multiplies<size_type>());
235 assert(num_elements_ != 0);
239 typedef boost::array<size_type,NumDims> size_list;
240 typedef boost::array<index,NumDims> index_list;
243 index origin_offset_;
244 size_type num_elements_;
245 size_list extent_list_;
246 index_list stride_list_;
247 index_list index_base_list_;
250 // const_multi_array_view cannot be assigned to (no deep copies!)
251 const_multi_array_view& operator=(const const_multi_array_view& other);
255 template <typename T, std::size_t NumDims>
256 class multi_array_view :
257 public const_multi_array_view<T,NumDims,T*>
259 typedef const_multi_array_view<T,NumDims,T*> super_type;
261 typedef typename super_type::value_type value_type;
262 typedef typename super_type::reference reference;
263 typedef typename super_type::iterator iterator;
264 typedef typename super_type::reverse_iterator reverse_iterator;
265 typedef typename super_type::const_reference const_reference;
266 typedef typename super_type::const_iterator const_iterator;
267 typedef typename super_type::const_reverse_iterator const_reverse_iterator;
268 typedef typename super_type::element element;
269 typedef typename super_type::size_type size_type;
270 typedef typename super_type::difference_type difference_type;
271 typedef typename super_type::index index;
272 typedef typename super_type::extent_range extent_range;
275 template <std::size_t NDims>
276 struct const_array_view {
277 typedef boost::detail::multi_array::const_multi_array_view<T,NDims> type;
280 template <std::size_t NDims>
282 typedef boost::detail::multi_array::multi_array_view<T,NDims> type;
285 // Assignment from other ConstMultiArray types.
286 template <typename ConstMultiArray>
287 multi_array_view& operator=(const ConstMultiArray& other) {
289 boost::detail::multi_array::
290 ConstMultiArrayConcept<ConstMultiArray,NumDims> >();
292 // make sure the dimensions agree
293 assert(other.num_dimensions() == this->num_dimensions());
294 assert(std::equal(other.shape(),other.shape()+this->num_dimensions(),
296 // iterator-based copy
297 std::copy(other.begin(),other.end(),begin());
302 multi_array_view& operator=(const multi_array_view& other) {
303 if (&other != this) {
304 // make sure the dimensions agree
305 assert(other.num_dimensions() == this->num_dimensions());
306 assert(std::equal(other.shape(),other.shape()+this->num_dimensions(),
308 // iterator-based copy
309 std::copy(other.begin(),other.end(),begin());
314 element* origin() { return this->base_+this->origin_offset_; }
316 template <class IndexList>
317 element& operator()(const IndexList& indices) {
318 return super_type::access_element(boost::type<element&>(),
320 indices,this->strides());
324 reference operator[](index idx) {
325 return super_type::access(boost::type<reference>(),
327 this->shape(),this->strides(),
328 this->index_bases());
332 // see generate_array_view in base.hpp
333 #if !defined(BOOST_MSVC) || BOOST_MSVC > 1300
336 template <int NumDims, int NDims> // else ICE
338 typename array_view<NDims>::type
339 operator[](const boost::detail::multi_array::
340 index_gen<NumDims,NDims>& indices) {
341 typedef typename array_view<NDims>::type return_type;
343 super_type::generate_array_view(boost::type<return_type>(),
353 return iterator(*this->index_bases(),origin(),
354 this->shape(),this->strides(),
355 this->index_bases());
359 return iterator(*this->index_bases()+*this->shape(),origin(),
360 this->shape(),this->strides(),
361 this->index_bases());
364 reverse_iterator rbegin() {
365 return reverse_iterator(end());
368 reverse_iterator rend() {
369 return reverse_iterator(begin());
372 // Using declarations don't seem to work for g++
373 // These are the proxies to work around this.
375 const element* origin() const { return super_type::origin(); }
377 template <class IndexList>
378 const element& operator()(const IndexList& indices) const {
379 return super_type::operator()(indices);
382 const_reference operator[](index idx) const {
383 return super_type::operator[](idx);
386 // see generate_array_view in base.hpp
387 #if !defined(BOOST_MSVC) || BOOST_MSVC > 1300
390 template <int NumDims, int NDims> // else ICE
392 typename const_array_view<NDims>::type
393 operator[](const boost::detail::multi_array::
394 index_gen<NumDims,NDims>& indices)
396 return super_type::operator[](indices);
399 const_iterator begin() const {
400 return super_type::begin();
403 const_iterator end() const {
404 return super_type::end();
407 const_reverse_iterator rbegin() const {
408 return super_type::rbegin();
411 const_reverse_iterator rend() const {
412 return super_type::rend();
415 #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
417 template <typename,std::size_t> friend class multi_array_impl_base;
419 public: // should be private
422 // constructor used by multi_array_impl_base::generate_array_view to
423 // generate array views
424 template <typename ExtentList, typename Index>
425 explicit multi_array_view(T* base,
426 const ExtentList& extents,
427 const boost::array<Index,NumDims>& strides) :
428 super_type(base,extents,strides) { }
432 } // namespace multi_array
433 } // namespace detail
436 // traits classes to get array_view types
438 template <typename Array, int N>
439 class array_view_gen {
440 typedef typename Array::element element;
442 typedef boost::detail::multi_array::multi_array_view<element,N> type;
445 template <typename Array, int N>
446 class const_array_view_gen {
447 typedef typename Array::element element;
449 typedef boost::detail::multi_array::const_multi_array_view<element,N> type;
454 #endif // BOOST_MULTI_ARRAY_VIEW_RG071301_HPP