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::detail::multi_array::
77 copy_n(values.begin(),num_dimensions(),index_base_list_.begin());
79 this->calculate_indexing_offset(stride_list_,index_base_list_);
82 void reindex(index value) {
83 index_base_list_.assign(value);
85 this->calculate_indexing_offset(stride_list_,index_base_list_);
88 size_type num_dimensions() const { return NumDims; }
90 size_type size() const { return extent_list_.front(); }
91 size_type max_size() const { return num_elements(); }
92 bool empty() const { return size() == 0; }
94 const size_type* shape() const {
95 return extent_list_.data();
98 const index* strides() const {
99 return stride_list_.data();
102 const T* origin() const { return base_+origin_offset_; }
104 size_type num_elements() const { return num_elements_; }
106 const index* index_bases() const {
107 return index_base_list_.data();
110 template <typename IndexList>
111 const element& operator()(IndexList indices) const {
112 return super_type::access_element(boost::type<const element&>(),
117 // Only allow const element access
118 const_reference operator[](index idx) const {
119 return super_type::access(boost::type<const_reference>(),
125 // see generate_array_view in base.hpp
126 #if !defined(BOOST_MSVC) || BOOST_MSVC > 1300
129 template <int NumDims, int NDims> // else ICE
131 typename const_array_view<NDims>::type
132 operator[](const boost::detail::multi_array::
133 index_gen<NumDims,NDims>& indices)
135 typedef typename const_array_view<NDims>::type return_type;
137 super_type::generate_array_view(boost::type<return_type>(),
144 const_iterator begin() const {
145 return const_iterator(*index_bases(),origin(),
146 shape(),strides(),index_bases());
149 const_iterator end() const {
150 return const_iterator(*index_bases()+(index)*shape(),origin(),
151 shape(),strides(),index_bases());
154 const_reverse_iterator rbegin() const {
155 return const_reverse_iterator(end());
158 const_reverse_iterator rend() const {
159 return const_reverse_iterator(begin());
163 template <typename OPtr>
164 bool operator==(const
165 const_multi_array_view<T,NumDims,OPtr>& rhs)
167 if(std::equal(extent_list_.begin(),
169 rhs.extent_list_.begin()))
170 return std::equal(begin(),end(),rhs.begin());
174 template <typename OPtr>
176 const_multi_array_view<T,NumDims,OPtr>& rhs)
178 return std::lexicographical_compare(begin(),end(),rhs.begin(),rhs.end());
181 template <typename OPtr>
182 bool operator!=(const
183 const_multi_array_view<T,NumDims,OPtr>& rhs)
185 return !(*this == rhs);
188 template <typename OPtr>
190 const_multi_array_view<T,NumDims,OPtr>& rhs)
195 template <typename OPtr>
196 bool operator<=(const
197 const_multi_array_view<T,NumDims,OPtr>& rhs)
199 return !(*this > rhs);
202 template <typename OPtr>
203 bool operator>=(const
204 const_multi_array_view<T,NumDims,OPtr>& rhs)
206 return !(*this < rhs);
210 #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
212 template <typename,std::size_t> friend class multi_array_impl_base;
213 template <typename,std::size_t,typename> friend class const_multi_array_view;
215 public: // should be protected
218 // This constructor is used by multi_array_impl_base::generate_array_view
220 template <typename ExtentList, typename Index>
221 explicit const_multi_array_view(TPtr base,
222 const ExtentList& extents,
223 const boost::array<Index,NumDims>& strides):
224 base_(base), origin_offset_(0) {
226 index_base_list_.assign(0);
228 // Get the extents and strides
229 boost::detail::multi_array::
230 copy_n(extents.begin(),NumDims,extent_list_.begin());
231 boost::detail::multi_array::
232 copy_n(strides.begin(),NumDims,stride_list_.begin());
234 // Calculate the array size
235 num_elements_ = std::accumulate(extent_list_.begin(),extent_list_.end(),
236 size_type(1),std::multiplies<size_type>());
238 assert(num_elements_ != 0);
242 typedef boost::array<size_type,NumDims> size_list;
243 typedef boost::array<index,NumDims> index_list;
246 index origin_offset_;
247 size_type num_elements_;
248 size_list extent_list_;
249 index_list stride_list_;
250 index_list index_base_list_;
253 // const_multi_array_view cannot be assigned to (no deep copies!)
254 const_multi_array_view& operator=(const const_multi_array_view& other);
258 template <typename T, std::size_t NumDims>
259 class multi_array_view :
260 public const_multi_array_view<T,NumDims,T*>
262 typedef const_multi_array_view<T,NumDims,T*> super_type;
264 typedef typename super_type::value_type value_type;
265 typedef typename super_type::reference reference;
266 typedef typename super_type::iterator iterator;
267 typedef typename super_type::reverse_iterator reverse_iterator;
268 typedef typename super_type::const_reference const_reference;
269 typedef typename super_type::const_iterator const_iterator;
270 typedef typename super_type::const_reverse_iterator const_reverse_iterator;
271 typedef typename super_type::element element;
272 typedef typename super_type::size_type size_type;
273 typedef typename super_type::difference_type difference_type;
274 typedef typename super_type::index index;
275 typedef typename super_type::extent_range extent_range;
278 template <std::size_t NDims>
279 struct const_array_view {
280 typedef boost::detail::multi_array::const_multi_array_view<T,NDims> type;
283 template <std::size_t NDims>
285 typedef boost::detail::multi_array::multi_array_view<T,NDims> type;
288 // Assignment from other ConstMultiArray types.
289 template <typename ConstMultiArray>
290 multi_array_view& operator=(const ConstMultiArray& other) {
292 boost::detail::multi_array::
293 ConstMultiArrayConcept<ConstMultiArray,NumDims> >();
295 // make sure the dimensions agree
296 assert(other.num_dimensions() == this->num_dimensions());
297 assert(std::equal(other.shape(),other.shape()+this->num_dimensions(),
299 // iterator-based copy
300 std::copy(other.begin(),other.end(),begin());
305 multi_array_view& operator=(const multi_array_view& other) {
306 if (&other != this) {
307 // make sure the dimensions agree
308 assert(other.num_dimensions() == this->num_dimensions());
309 assert(std::equal(other.shape(),other.shape()+this->num_dimensions(),
311 // iterator-based copy
312 std::copy(other.begin(),other.end(),begin());
317 element* origin() { return this->base_+this->origin_offset_; }
319 template <class IndexList>
320 element& operator()(const IndexList& indices) {
321 return super_type::access_element(boost::type<element&>(),
323 indices,this->strides());
327 reference operator[](index idx) {
328 return super_type::access(boost::type<reference>(),
330 this->shape(),this->strides(),
331 this->index_bases());
335 // see generate_array_view in base.hpp
336 #if !defined(BOOST_MSVC) || BOOST_MSVC > 1300
339 template <int NumDims, int NDims> // else ICE
341 typename array_view<NDims>::type
342 operator[](const boost::detail::multi_array::
343 index_gen<NumDims,NDims>& indices) {
344 typedef typename array_view<NDims>::type return_type;
346 super_type::generate_array_view(boost::type<return_type>(),
356 return iterator(*this->index_bases(),origin(),
357 this->shape(),this->strides(),
358 this->index_bases());
362 return iterator(*this->index_bases()+(index)*this->shape(),origin(),
363 this->shape(),this->strides(),
364 this->index_bases());
367 reverse_iterator rbegin() {
368 return reverse_iterator(end());
371 reverse_iterator rend() {
372 return reverse_iterator(begin());
375 // Using declarations don't seem to work for g++
376 // These are the proxies to work around this.
378 const element* origin() const { return super_type::origin(); }
380 template <class IndexList>
381 const element& operator()(const IndexList& indices) const {
382 return super_type::operator()(indices);
385 const_reference operator[](index idx) const {
386 return super_type::operator[](idx);
389 // see generate_array_view in base.hpp
390 #if !defined(BOOST_MSVC) || BOOST_MSVC > 1300
393 template <int NumDims, int NDims> // else ICE
395 typename const_array_view<NDims>::type
396 operator[](const boost::detail::multi_array::
397 index_gen<NumDims,NDims>& indices)
399 return super_type::operator[](indices);
402 const_iterator begin() const {
403 return super_type::begin();
406 const_iterator end() const {
407 return super_type::end();
410 const_reverse_iterator rbegin() const {
411 return super_type::rbegin();
414 const_reverse_iterator rend() const {
415 return super_type::rend();
418 #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
420 template <typename,std::size_t> friend class multi_array_impl_base;
422 public: // should be private
425 // constructor used by multi_array_impl_base::generate_array_view to
426 // generate array views
427 template <typename ExtentList, typename Index>
428 explicit multi_array_view(T* base,
429 const ExtentList& extents,
430 const boost::array<Index,NumDims>& strides) :
431 super_type(base,extents,strides) { }
435 } // namespace multi_array
436 } // namespace detail
439 // traits classes to get array_view types
441 template <typename Array, int N>
442 class array_view_gen {
443 typedef typename Array::element element;
445 typedef boost::detail::multi_array::multi_array_view<element,N> type;
448 template <typename Array, int N>
449 class const_array_view_gen {
450 typedef typename Array::element element;
452 typedef boost::detail::multi_array::const_multi_array_view<element,N> type;
457 #endif // BOOST_MULTI_ARRAY_VIEW_RG071301_HPP