boost-react-native-bundle

<sect2 id="multi_array_ref"> <title><literal>multi_array_ref</literal></title> <para> <literal>multi_array_ref</literal> is a multi-dimensional container adaptor. It provides the MultiArray interface over any contiguous block of elements. <literal>multi_array_ref</literal> exports the same interface as <literal>multi_array</literal>, with the exception of the constructors. </para> <formalpara> <title>Model Of.</title> <para> <literal>multi_array_ref</literal> models <link linkend="MultiArray">MultiArray</link>, <ulink url="../../../libs/utility/CopyConstructible.html">CopyConstructible</ulink>. and depending on the element type, it may also model <ulink url="http://www.sgi.com/tech/stl/EqualityComparable.html">EqualityComparable</ulink> and <ulink url="http://www.sgi.com/tech/stl/LessThanComparable.html">LessThanComparable</ulink>. Detailed descriptions are provided here only for operations that are not described in the <literal>multi_array</literal> reference. </para> </formalpara> <formalpara> <title>Synopsis</title> <programlisting> <![CDATA[ namespace boost { template <typename ValueType, std::size_t NumDims> class multi_array_ref { public: // types: typedef ValueType element; typedef *unspecified* value_type; typedef *unspecified* reference; typedef *unspecified* const_reference; typedef *unspecified* difference_type; typedef *unspecified* iterator; typedef *unspecified* const_iterator; typedef *unspecified* reverse_iterator; typedef *unspecified* const_reverse_iterator; typedef multi_array_types::size_type size_type; typedef multi_array_types::index index; typedef multi_array_types::index_gen index_gen; typedef multi_array_types::index_range index_range; typedef multi_array_types::extent_gen extent_gen; typedef multi_array_types::extent_range extent_range; typedef *unspecified* storage_order_type; // template typedefs template <std::size_t Dims> struct subarray; template <std::size_t Dims> struct const_subarray; template <std::size_t Dims> struct array_view; template <std::size_t Dims> struct const_array_view; static const std::size_t dimensionality = NumDims; // constructors and destructors template <typename ExtentList> explicit multi_array_ref(element* data, const ExtentList& sizes, const storage_order_type& store = c_storage_order()); explicit multi_array_ref(element* data, const extents_tuple& ranges, const storage_order_type& store = c_storage_order()); multi_array_ref(const multi_array_ref& x); ~multi_array_ref(); // modifiers multi_array_ref& operator=(const multi_array_ref& x); template <class Array> multi_array_ref& operator=(const Array& x); // iterators: iterator begin(); iterator end(); const_iterator begin() const; const_iterator end() const; reverse_iterator rbegin(); reverse_iterator rend(); const_reverse_iterator rbegin() const; const_reverse_iterator rend() const; // capacity: size_type size() const; size_type num_elements() const; size_type num_dimensions() const; // element access: template <typename IndexList> element& operator()(const IndexList& indices); template <typename IndexList> const element& operator()(const IndexList& indices) const; reference operator[](index i); const_reference operator[](index i) const; array_view<Dims>::type operator[](const indices_tuple& r); const_array_view<Dims>::type operator[](const indices_tuple& r) const; // queries element* data(); const element* data() const; element* origin(); const element* origin() const; const size_type* shape() const; const index* strides() const; const index* index_bases() const; const storage_order_type& storage_order() const; // comparators bool operator==(const multi_array_ref& rhs); bool operator!=(const multi_array_ref& rhs); bool operator<(const multi_array_ref& rhs); bool operator>(const multi_array_ref& rhs); bool operator>=(const multi_array_ref& rhs); bool operator<=(const multi_array_ref& rhs); // modifiers: template <typename InputIterator> void assign(InputIterator begin, InputIterator end); template <typename SizeList> void reshape(const SizeList& sizes) template <typename BaseList> void reindex(const BaseList& values); void reindex(index value); }; ]]> </programlisting> </formalpara> <formalpara> <title>Constructors</title> <variablelist> <varlistentry> <term><programlisting>template <typename ExtentList> explicit multi_array_ref(element* data, const ExtentList& sizes, const storage_order& store = c_storage_order(), const Allocator& alloc = Allocator()); </programlisting></term> <listitem> <para> This constructs a <literal>multi_array_ref</literal> using the specified parameters. <literal>sizes</literal> specifies the shape of the constructed <literal>multi_array_ref</literal>. <literal>store</literal> specifies the storage order or layout in memory of the array dimensions. <literal>alloc</literal> is used to allocate the contained elements. </para> <formalpara><title><literal>ExtentList</literal> Requirements</title> <para> <literal>ExtentList</literal> must model <ulink url="../../utility/Collection.html">Collection</ulink>. </para> </formalpara> <formalpara><title>Preconditions</title> <para><literal>sizes.size() == NumDims;</literal></para> </formalpara> </listitem> </varlistentry> <varlistentry> <term> <programlisting><![CDATA[explicit multi_array_ref(element* data, extent_gen::gen_type<NumDims>::type ranges, const storage_order& store = c_storage_order());]]> </programlisting></term> <listitem> <para> This constructs a <literal>multi_array_ref</literal> using the specified parameters. <literal>ranges</literal> specifies the shape and index bases of the constructed multi_array_ref. It is the result of <literal>NumDims</literal> chained calls to <literal>extent_gen::operator[]</literal>. <literal>store</literal> specifies the storage order or layout in memory of the array dimensions. </para> </listitem> </varlistentry> <varlistentry> <term><programlisting> <![CDATA[multi_array_ref(const multi_array_ref& x);]]> </programlisting></term> <listitem> <para>This constructs a shallow copy of <literal>x</literal>. </para> <formalpara> <title>Complexity</title> <para> Constant time (for contrast, compare this to the <literal>multi_array</literal> class copy constructor. </para></formalpara> </listitem> </varlistentry> </variablelist> </formalpara> <formalpara> <title>Modifiers</title> <variablelist> <varlistentry> <term><programlisting> <![CDATA[multi_array_ref& operator=(const multi_array_ref& x); template <class Array> multi_array_ref& operator=(const Array& x);]]> </programlisting> </term> <listitem> <para>This performs an element-wise copy of <literal>x</literal> into the current <literal>multi_array_ref</literal>.</para> <formalpara> <title><literal>Array</literal> Requirements</title> <para><literal>Array</literal> must model MultiArray. </para></formalpara> <formalpara> <title>Preconditions</title> <para> <programlisting>std::equal(this->shape(),this->shape()+this->num_dimensions(), x.shape());</programlisting></para> </formalpara> <formalpara> <title>Postconditions</title> <para> <programlisting>(*.this) == x;</programlisting> </para> </formalpara> <formalpara> <title>Complexity</title> <para>The assignment operators perform O(<literal>x.num_elements()</literal>) calls to <literal>element</literal>'s copy constructor.</para></formalpara> </listitem> </varlistentry> </variablelist> </formalpara> </sect2>