std::extents,std::dextents,std::dims

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std::mdspan

Member functions
mdspan::mdspan
mdspan::operator=
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mdspan::operator[]
Observers
mdspan::rank
mdspan::rank_dynamic
mdspan::static_extent
mdspan::extent
mdspan::size
mdspan::empty
mdspan::stride
mdspan::extents
mdspan::data_handle
mdspan::mapping
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mdspan::is_uniquemdspan::is_exhaustivemdspan::is_stridedmdspan::is_always_uniquemdspan::is_always_exhaustivemdspan::is_always_strided

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swap(std::mdspan)
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submdspan (C++26)
submdspan_extents (C++26)
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extentsdextents
dims (C++26)
default_accessor
aligned_accessor (C++26)
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layout_left
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layout_left_padded (C++26)
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full_extent (C++26)
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submdspan_mapping_result (C++26)
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std::extents

Member functions
extents::extents
Observers
extents::rank
extents::rank_dynamic
extents::static_extent
extents::extent
Helpers
extents::fwd-prod-of-extents
extents::rev-prod-of-extents
extents::index-cast
extents::dynamic-index
extents::dynamic-index-inv
Non-member functions
extents::operator==
Deduction guides

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Defined in header`<mdspan>`
template<class IndexType,std::size_t...Extents> class extents;	(1)	(since C++23)
template<class IndexType,std::size_t Rank> using dextents=/* see below */	(2)	(since C++23)
template<std::size_t Rank,class IndexType=std::size_t> using dims= std::dextents<IndexType, Rank>;	(3)	(since C++26)

1) Represents a multidimensional index space of rank equal tosizeof...(Extents).

2) A convenient alias template for an all-dynamicextents. Letd denotestd::dynamic_extent, each specialization of itdextents<IndexType, Rank> is equivalent toextents<IndexType/*, d, d, ..., d*/> (i.e.d is repeated a total ofRank times).

3) A convenient alias template for an all-dynamicextents withstd::size_t as the default index type.

Each specialization ofextents modelsregular and isTriviallyCopyable.

[edit]Template parameters

IndexType	-	the type of each non-dynamic`Extents`. Shall be a signed or unsigned integer type. Otherwise, the program is ill-formed
Extents	-	represents extent (size of an integer interval) for each rank index. Each element of it is either equal tostd::dynamic_extent (in this case, it represents adynamic extent and the extent size will be determined dynamically), or is representable as a value of type`IndexType` (then it represents astatic extent and the extent size is just the value of it), or else the program is ill-formed
Rank	-	denotes the rank of an all-dynamic`extents`

[edit]Member types

Member type	Definition
`index_type`	`IndexType`
`size_type`	std::make_unsigned_t<index_type>
`rank_type`	std::size_t

[edit]Data members

Member name	Definition
std::array<index_type, rank_dynamic()>`dynamic-extents`(private)	An array which stores the size of each dynamic extents. (exposition-only member object*)

[edit]Member functions

(constructor)	constructs an`extents` (public member function)[edit]
Observers
rank [static]	returns the static rank of an`extents` (public static member function)[edit]
rank_dynamic [static]	returns the dynamic rank of an`extents` (public static member function)[edit]
static_extent [static]	returns static extent size of an`extents` at a certain rank index (public static member function)[edit]
extent	returns dynamic extent size of an`extents` at a certain rank index (public member function)[edit]
Helpers
fwd-prod-of-extents	returns the product of extent size in range`[`0`,` i`)` (exposition-only member function*)[edit]
rev-prod-of-extents	returns the product of extents size in range`[`i+1`,` rank()`)` (exposition-only member function*)[edit]
index-cast	casts the input into an integer type (exposition-only member function*)[edit]
dynamic-index (private)	returns the number of dynamic extents below a certain rank index (exposition-only member function*)[edit]
dynamic-index-inv (private)	returns the number`r` such that in range`[`0`,` r+1`)` there is exactly`i + 1` dynamic extents for a certain argument`i` (exposition-only member function*)[edit]

[edit]Non-member functions

operator==

(C++23)

compare underlying extents in each dimension of twoextents
(function)[edit]

[edit]Deduction guides(C++23)

[edit]Example

This section is incomplete
Reason: no example

[edit]See also

rank (C++11)	obtains the number of dimensions of an array type (class template)[edit]
extent (C++11)	obtains the size of an array type along a specified dimension (class template)[edit]