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std::layout_right::mapping(3) C++ Standard Libary std::layout_right::mapping(3)

NAME

std::layout_right::mapping - std::layout_right::mapping

Synopsis


Defined in header <mdspan>
template< class Extents > (since C++23)
class layout_right::mapping;


The class template layout_right::mapping controls how multidimensional indices are
mapped in a row-major manner to a one-dimensional value representing the offset. The
mapping has stride 1 at rightmost extent and strides increase right-to-left as the
products of extents.


Every specialization of mapping is a LayoutMapping and a TriviallyCopyable type
which satisfies regular.


The program is ill-formed if the size of the multidimensional index space Extents()
is not representable as a value of type Extents::index_type when
Extents::rank_dynamic() is 0.

Template parameters


Extents - specifies number of dimensions, their sizes, and which are known at
compile time. Must be a specialization of std::extents.

Member types


Member type Definition
extents_type Extents
index_type extents_type::index_type
size_type extents_type::size_type
rank_type extents_type::rank_type
layout_type std::layout_right

Member objects


Member name Definition
extents_ (private) The extents of type extents_type.
(exposition-only member object*)

Member functions


constructor constructs a new mapping
(public member function)
operator= assigns a mapping
(public member function)

Observers


extents obtains the extents object
(public member function)
required_span_size returns the required size of the mapping
(public member function)
operator() maps multidimensional indices into an offset value
(public member function)
is_unique determines if this mapping is unique (every combination of
[static] indexes maps to a different underlying element)
(public static member function)
is_exhaustive determines if this mapping is exhaustive (every underlying
[static] element can be accessed with some combination of indexes)
(public static member function)
is_strided determines if this mapping is unique (every combination of
[static] indexes maps to a different underlying element)
(public static member function)
is_always_unique determines if this layout mapping is always unique
[static] (public static member function)
is_always_exhaustive determines if this layout mapping is always exhaustive
[static] (public static member function)
is_always_strided determines if this layout mapping is always strided
[static] (public static member function)
stride obtains the stride along the specified dimension
(public member function)

Non-member functions


compares this layout mapping with
operator== other mapping
(function template)
submdspan_mapping(std::layout_right::mapping) calculates the mapping and data handle
(C++26) offset used for subdmspan
(public member function)

See also


mapping a layout mapping of layout_left
(public member class template of std::layout_left)
mapping a layout mapping of layout_stride
(public member class template of std::layout_stride)

2024.06.10 http://cppreference.com