mpi::group

#include <mpi/group.hpp>

Detailed Description

C++ wrapper around MPI_Group providing various convenience functions.

It stores an MPI_Group object as its only member which by default is set to MPI_GROUP_NULL. The underlying MPI_Group object is automatically freed when a group object goes out of scope.

This class follows move-only semantics and takes ownership of the wrapped MPI_Group object.

All functions that make direct calls to the MPI C library throw an exception in case the call fails.

Definition at line 46 of file group.hpp.

Public Member Functions
	group ()=default
	Construct a group with MPI_GROUP_NULL.
	group (communicator c)
	Create a group from a communicator by calling MPI_Comm_group.
	group (group &&other) noexcept
	Move constructor leaves moved-from object with MPI_GROUP_NULL.
	group (group const &)=delete
	Deleted copy constructor.
	group (MPI_Group grp)
	Take ownership of an existing MPI_Group object.
	~group ()
	Destructor calls free() to release the group.
void	free () noexcept
	Free the group by calling MPI_Group_free (if it is not is_null()).
MPI_Group	get () const noexcept
	Get the wrapped MPI_Group object.
group	include (std::vector< int > const &ranks) const
	Create a new group by calling MPI_Group_incl.
bool	is_null () const noexcept
	Check if the contained MPI_Group is MPI_GROUP_NULL.
group &	operator= (group &&rhs) noexcept
	Move assignment operator leaves moved-from object with MPI_GROUP_NULL.
group &	operator= (group const &)=delete
	Deleted copy assignment operator.
int	rank () const
	Get the rank of the calling process in the group.
int	size () const
	Get the size of the group.

Constructor & Destructor Documentation

group() [1/2]

mpi::group::group ( MPI_Group grp )

inlineexplicit

Take ownership of an existing MPI_Group object.

Parameters

grp	MPI_Group to be handled.

Definition at line 76 of file group.hpp.

group() [2/2]

mpi::group::group ( communicator c )

inlineexplicit

Create a group from a communicator by calling MPI_Comm_group.

Parameters

c	mpi::communicator from which to create a group.

Definition at line 82 of file group.hpp.

Member Function Documentation

include()

group mpi::group::include ( std::vector< int > const & ranks ) const

inlinenodiscard

Create a new group by calling MPI_Group_incl.

It produces a new group by reordering the existing group and taking only listed members.

Parameters

ranks

List of ranks to include in the new group.

Returns

New group containing only the listed members.

Definition at line 120 of file group.hpp.

rank()

int mpi::group::rank ( ) const

inlinenodiscard

Get the rank of the calling process in the group.

Returns

The result of MPI_Group_rank if mpi::has_env is true, otherwise 0.

Definition at line 96 of file group.hpp.

size()

int mpi::group::size ( ) const

inlinenodiscard

Get the size of the group.

Returns

The result of MPI_Group_size if mpi::has_env is true, otherwise 1.

Definition at line 106 of file group.hpp.

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

• mpi/group.hpp