array< T, Size > Struct Template Reference

Detailed Description

template<class T, size_t Size>
struct Vc::array< T, Size >

This is std::array with additional subscript operators supporting gather and scatter operations.

The std::array documentation applies.

Gathers from structured data (AoS: arrays of struct) are possible via a special subscript operator. Example:

Vc::array<float, 100> data;
std::iota(data.begin(), data.end(), 0.f);  // fill with values 0, 1, 2, ...
auto indexes = float_v::IndexType::IndexesFromZero();
float_v gathered = data[indexes];  // gathered == [0, 1, 2, ...]

This also works for gathers into arrays of structures:

struct Point { float x, y, z; };
Vc::array<Point, 100> points;
// fill points ...
auto indexes = float_v::IndexType::IndexesFromZero();
float_v xs = data[indexes][&Point::x];  // [points[0].x, points[1].x, points[2].x, ...]
float_v ys = data[indexes][&Point::y];  // [points[0].y, points[1].y, points[2].y, ...]
float_v zs = data[indexes][&Point::z];  // [points[0].z, points[1].z, points[2].z, ...]

Arrays may also be nested:

 :
Vc::array<Vc::array<float, 3>, 100> points;
// fill points ...
auto indexes = float_v::IndexType::IndexesFromZero();
float_v xs = data[indexes][0];  // [points[0][0], points[1][0], points[2][0], ...]
float_v ys = data[indexes][1];  // [points[0][1], points[1][1], points[2][1], ...]
float_v zs = data[indexes][2];  // [points[0][2], points[1][2], points[2][2], ...]

Definition at line 86 of file array.

Public Member Functions
Data-Parallel Subscripting for Gather & Scatter
template<typename I >
auto	operator[] (I &&arg_) -> decltype(subscript_operator(*this, std::forward< I >(arg_)))
template<typename I >
auto	operator[] (I &&arg_) const -> decltype(subscript_operator(*this, std::forward< I >(arg_)))

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The documentation for this struct was generated from the following file:

• /home/axel/build/Vc/Vc/Vc/array