std::extents<IndexType,Extents...>::extent

 

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std::mdspan

Member functions mdspan::mdspan mdspan::operator= Element access 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 mdspan::accessor mdspan::is_uniquemdspan::is_exhaustivemdspan::is_stridedmdspan::is_always_uniquemdspan::is_always_exhaustivemdspan::is_always_strided

Non-member functions swap(std::mdspan) Subviews submdspan (C++26) submdspan_extents (C++26) Helper types and templates extentsdextentsdims (C++26) default_accessor Layout mapping policies layout_left layout_right layout_stride layout_left_padded (C++26) layout_right_padded (C++26) Subviews helpers full_extent (C++26) strided_slice (C++26) submdspan_mapping_result (C++26) Deduction guides

 

std::extents

Member functions

extents::extents

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extents::rank

extents::rank_dynamic

extents::static_extent

extents::extent

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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

 

constexpr index_type extent( rank_type i ) const noexcept;		(since C++23)

Returns dynamic extent size of an extents at a certain rank index.

Parameters

i

-

The rank index to get the extent size of

Return value

The dynamic extent size of an extents at a certain rank index.

Example

Run this code

#include <iostream>
#include <mdspan>
 
int main()
{
    std::extents<int, 1, 2> e1;
    std::extents<int, 3, std::dynamic_extent, std::dynamic_extent> e2(4, 5);
    std::cout << e1.extent(0) << ", " << e1.extent(1) << '\n';
    std::cout << e2.extent(0) << ", " << e2.extent(1) << ", " << e2.extent(2) << '\n';
}

Output:

1, 2
3, 4, 5

See also

static_extent [static]	returns static extent size of an extents at a certain rank index (public static member function)
extent (C++11)	obtains the size of an array type along a specified dimension (class template)