mpi::lazy< mpi::tag::gather, A >

#include <nda/mpi/gather.hpp>

Detailed Description

template<nda::Array A>
struct mpi::lazy< mpi::tag::gather, A >

Specialization of the mpi::lazy class for nda::Array types and the mpi::tag::gather tag.

An object of this class is returned when gathering nda::Array objects across multiple MPI processes.

It models an nda::ArrayInitializer, that means it can be used to initialize and assign to nda::basic_array and nda::basic_array_view objects. The target array will be a concatenation of the input arrays along the first dimension (see nda::concatenate).

See nda::mpi_gather for an example.

Template Parameters

A	nda::Array type to be gathered.

Definition at line 50 of file gather.hpp.

Public Types
using	const_view_type = decltype(std::declval<const A>()())
	Const view type of the array/view stored in the lazy object.
using	value_type = typename std::decay_t<A>::value_type
	Value type of the array/view.

Public Member Functions
template<nda::Array T>
void	invoke (T &&target) const
	Execute the lazy MPI operation and write the result to a target array/view.
auto	shape () const
	Compute the shape of the target array.

Public Attributes
const bool	all {false}
	Should all processes receive the result.
mpi::communicator	comm
	MPI communicator.
const_view_type	rhs
	View of the array/view to be gathered.
const int	root {0}
	MPI root process.

Member Function Documentation

invoke()

template<nda::Array A>

template<nda::Array T>

void mpi::lazy< mpi::tag::gather, A >::invoke ( T && target ) const

inline

Execute the lazy MPI operation and write the result to a target array/view.

Template Parameters

T	nda::Array type of the target array/view.

Parameters

target

Target array/view.

Definition at line 98 of file gather.hpp.

shape()

template<nda::Array A>

auto mpi::lazy< mpi::tag::gather, A >::shape ( ) const

inlinenodiscard

Compute the shape of the target array.

It is assumed that the shape of the input array is the same for all MPI processes except for the first dimension. The target shape will then be the same as the input shape, except that the extent of its first dimension will be the sum of the extents of the input arrays along the first dimension.

Warning

This makes an MPI call.

Returns

Shape of the target array.

Definition at line 80 of file gather.hpp.

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

• nda/mpi/gather.hpp