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

 

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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

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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

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extents::operator==

Deduction guides

 

static constexpr rank_type rank() const noexcept;		(since C++23)

Returns the number of dimensions in extents.

Parameters

(none)

Return value

The number of dimensions.

Example

Run this code

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

Output:

2, 3

See also

rank_dynamic [static]	returns the dynamic rank of an extents (public static member function)
rank (C++11)	obtains the number of dimensions of an array type (class template)