stapl::balanced_partition< Dom, Integral > Struct Template Reference

Partition a one-dimensional domain into balanced subdomains. More...

Public Member Functions
	balanced_partition (value_type const &dom, size_t p=get_num_locations())
	balanced_partition ()
	Create a partition with no domain. Leaves the partition in an inconsistent state and must be used in conjunction with set_domain.
	balanced_partition (value_type const &domain, balanced_partition const &other)
	Copy constructor using instead the given domain.
domain_type	domain () const
	Get the partition's domain [0, .., p-1].
void	set_domain (value_type const &dom)
	Set the global domain to partition. More...
value_type	operator[] (index_type idx) const
	Return the subdomain at a given index. This is the inverse of find. More...
boost::optional< value_type >	try_get_domain (index_type pid) const
	Returns the domain of gids that map to the specified partition if the mapping from GID to partition id is recognized. More...
size_t	size () const
	Return the number of partitions generated.
value_type const &	global_domain () const
	Return the original domain that was used to create subdomains.
index_type	find (gid_type const &g) const
	Returns the index of the partition that contains the gid g. More...
template<typename ODom , typename MFG >
std::vector< std::pair< domain_type, bool > >	contained_in (ODom const &dom, MFG const &mfg)
	Determine which partition has the elements referenced for the given domain. More...

Public Types
using	domain_type = indexed_domain< size_t >
	The domain of the partitioner itself (i.e., the domain [0, ..., p-1])
using	index_type = typename domain_type::index_type
	Type used to describe the i'th subdomain.
using	value_type = Dom
	Type of the subdomains produced by the partition.
using	gid_type = typename value_type::index_type
	Type of the GIDs in the subdomains.
using	size_type = typename value_type::size_type
	Type of the size of the subdomains.

Protected Attributes
value_type	m_domain
	The global original domain.
size_t	m_npart
	The number of partitions.

Detailed Description

template<typename Dom, bool Integral = std::is_integral<typename Dom::index_type>::value>
struct stapl::balanced_partition< Dom, Integral >

Partition a one-dimensional domain into balanced subdomains.

If the given domain contains the GIDs [0, 1, ..., n-1] and the number of partitions to generate is p, then each subdomain will have size n/p and will contain contiguous chunks of GID in domain order. In the case that the number of elements does not evenly divide the requested number of partitions, the remaining elements are evenly distributed across the subdomains, guaranteeing that no two subdomains differ in size by more than one.

Template Parameters

Dom	Type of the domain to be partitioned

Constructor & Destructor Documentation

balanced_partition()

template<typename Dom, bool Integral = std::is_integral<typename Dom::index_type>::value>

stapl::balanced_partition< Dom, Integral >::balanced_partition	(	value_type const &	dom,
		size_t	p = get_num_locations()
	)

Create a partition with a domain and a partitioning factor.

Parameters

dom	The domain to partition
p	The number of partitions to generate

Member Function Documentation

set_domain()

template<typename Dom, bool Integral = std::is_integral<typename Dom::index_type>::value>

void stapl::balanced_partition< Dom, Integral >::set_domain

(

value_type const &

dom

)

Set the global domain to partition.

Parameters

dom	The domain to partition

operator[]()

template<typename Dom, bool Integral = std::is_integral<typename Dom::index_type>::value>

value_type stapl::balanced_partition< Dom, Integral >::operator[]

(

index_type

idx

)

const

Return the subdomain at a given index. This is the inverse of find.

Parameters

idx	The index of the subdomain, which should be from 0 to size() - 1.

try_get_domain()

template<typename Dom, bool Integral = std::is_integral<typename Dom::index_type>::value>

boost::optional<value_type> stapl::balanced_partition< Dom, Integral >::try_get_domain

(

index_type

pid

)

const

Returns the domain of gids that map to the specified partition if the mapping from GID to partition id is recognized.

This is functionally equivalent to the index operator for this partition.

Parameters

pid	id of the partition whose domain is required

find()

template<typename Dom, bool Integral = std::is_integral<typename Dom::index_type>::value>

index_type stapl::balanced_partition< Dom, Integral >::find

(

gid_type const &

g

)

const

Returns the index of the partition that contains the gid g.

Parameters

g	gid to find

Returns

The index of the subdomain that contains g

contained_in()

template<typename Dom, bool Integral = std::is_integral<typename Dom::index_type>::value>

template<typename ODom , typename MFG >

std::vector<std::pair<domain_type,bool> > stapl::balanced_partition< Dom, Integral >::contained_in	(	ODom const &	dom,
		MFG const &	mfg
	)

Determine which partition has the elements referenced for the given domain.

The returned information is a collection (possibly empty) of pairs. Each pair contains information about which partitions are included in the given domain and how they are included (True: if is fully contained, False: if is partially included). The returned collection only has elements if there is at least one partition that contains elements on the given domain.

Example:

Partition: [0..3],[4..6],[7..9],[10..13]
Given domain: [2..9]
Returns: {([0..0],False),([1..2],True)}

Parameters

dom	Domain to compare
mfg	Mapping function generator used to get the associated mapping function to each partition. The generated mapping function is used to project generated partitioned domains into the given domain.

Returns

a vector of pairs.

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

• containers/partitions/balanced.hpp