#include <EliminationTree.h>

Classes
struct	Node

Public Types
typedef GRAPH	FactorGraphType
	The factor graph type.

typedef GRAPH::FactorType	FactorType
	The type of factors.

typedef std::shared_ptr< FactorType >	sharedFactor
	Shared pointer to a factor.

typedef BAYESNET	BayesNetType
	The BayesNet corresponding to FACTOR.

typedef BayesNetType::ConditionalType	ConditionalType
	The type of conditionals.

typedef std::shared_ptr< ConditionalType >	sharedConditional
	Shared pointer to a conditional.

typedef GRAPH::Eliminate	Eliminate

typedef std::shared_ptr< Node >	sharedNode
	Shared pointer to Node.

Public Member Functions
	~EliminationTree ()

Protected Types
typedef EliminationTree< BAYESNET, GRAPH >	This
	This class.

typedef std::shared_ptr< This >	shared_ptr
	Shared pointer to this class.

Protected Attributes
FastVector< sharedNode >	roots_

FastVector< sharedFactor >	remainingFactors_

Standard Constructors
	EliminationTree (const FactorGraphType &factorGraph, const VariableIndex &structure, const Ordering &order)

	EliminationTree (const FactorGraphType &factorGraph, const Ordering &order)

	EliminationTree (const This &other)

This &	operator= (const This &other)

Standard Interface
std::pair< std::shared_ptr< BayesNetType >, std::shared_ptr< FactorGraphType > >	eliminate (Eliminate function) const

Testable
bool	equals (const This &other, double tol=1e-9) const

void	print (const std::string &name="EliminationTree: ", const KeyFormatter &formatter=DefaultKeyFormatter) const

Advanced Interface
class	::EliminationTreeTester
	Allow access to constructor and add methods for testing purposes.

	EliminationTree ()
	Protected default constructor.

const FastVector< sharedNode > &	roots () const

const FastVector< sharedFactor > &	remainingFactors () const

void	swap (This &other)

Detailed Description

template<class BAYESNET, class GRAPH>
class gtsam::EliminationTree< BAYESNET, GRAPH >

An elimination tree is a data structure used intermediately during elimination. In future versions it will be used to save work between multiple eliminations.

When a variable is eliminated, a new factor is created by combining that variable's neighboring factors. The new combined factor involves the combined factors' involved variables. When the lowest-ordered one of those variables is eliminated, it consumes that combined factor. In the elimination tree, that lowest-ordered variable is the parent of the variable that was eliminated to produce the combined factor. This yields a tree in general, and not a chain because of the implicit sparse structure of the resulting Bayes net.

This structure is examined even more closely in a JunctionTree, which additionally identifies cliques in the chordal Bayes net.

Constructor & Destructor Documentation

◆ EliminationTree() [1/3]

template<class BAYESNET , class GRAPH >

gtsam::EliminationTree< BAYESNET, GRAPH >::EliminationTree	(	const FactorGraphType &	factorGraph,
		const VariableIndex &	structure,
		const Ordering &	order
	)

protected

Build the elimination tree of a factor graph using pre-computed column structure.

Parameters

factorGraph	The factor graph for which to build the elimination tree
structure	The set of factors involving each variable. If this is not precomputed, you can call the Create(const FactorGraph<DERIVEDFACTOR>&) named constructor instead.

Returns: The elimination tree

◆ EliminationTree() [2/3]

template<class BAYESNET , class GRAPH >

gtsam::EliminationTree< BAYESNET, GRAPH >::EliminationTree	(	const FactorGraphType &	factorGraph,
		const Ordering &	order
	)

protected

Build the elimination tree of a factor graph. Note that this has to compute the column structure as a VariableIndex, so if you already have this precomputed, use the other constructor instead.

Parameters

factorGraph The factor graph for which to build the elimination tree

◆ EliminationTree() [3/3]

template<class BAYESNET, class GRAPH>

gtsam::EliminationTree< BAYESNET, GRAPH >::EliminationTree ( const This & other )

inlineprotected

Copy constructor - makes a deep copy of the tree structure, but only pointers to factors are copied, factors are not cloned.

◆ ~EliminationTree()

template<class BAYESNET , class GRAPH >

gtsam::EliminationTree< BAYESNET, GRAPH >::~EliminationTree ( )

Destructor Using default destructor causes stack overflow for large trees due to recursive destruction of nodes; so we manually decrease the reference count of each node in the tree through a BFS, and the nodes with reference count 0 will be deleted. Please see PR-1441 for more details.

Member Function Documentation

◆ eliminate()

template<class BAYESNET , class GRAPH >

std::pair< std::shared_ptr< BAYESNET >, std::shared_ptr< GRAPH > > gtsam::EliminationTree< BAYESNET, GRAPH >::eliminate ( Eliminate function ) const

Eliminate the factors to a Bayes net and remaining factor graph

Parameters

function The function to use to eliminate, see the namespace functions in GaussianFactorGraph.h

Returns: The Bayes net and factor graph resulting from elimination

◆ equals()

template<class BAYESNET , class GRAPH >

bool gtsam::EliminationTree< BAYESNET, GRAPH >::equals	(	const This &	other,
		double	tol = `1e-9`
	)		const

protected

Test whether the tree is equal to another

◆ operator=()

template<class BAYESNET , class GRAPH >

EliminationTree< BAYESNET, GRAPH > & gtsam::EliminationTree< BAYESNET, GRAPH >::operator= ( const This & other )

protected

Assignment operator - makes a deep copy of the tree structure, but only pointers to factors are copied, factors are not cloned.

◆ print()

template<class BAYESNET , class GRAPH >

void gtsam::EliminationTree< BAYESNET, GRAPH >::print	(	const std::string &	name = `"EliminationTree< BAYESNET, GRAPH >: "`,
		const KeyFormatter &	formatter = `DefaultKeyFormatter`
	)		const

Print the tree to cout

◆ remainingFactors()

template<class BAYESNET, class GRAPH>

const FastVector<sharedFactor>& gtsam::EliminationTree< BAYESNET, GRAPH >::remainingFactors ( ) const

inline

Return the remaining factors that are not pulled into elimination

◆ roots()

template<class BAYESNET, class GRAPH>

const FastVector<sharedNode>& gtsam::EliminationTree< BAYESNET, GRAPH >::roots ( ) const

inline

Return the set of roots (one for a tree, multiple for a forest)

◆ swap()

template<class BAYESNET , class GRAPH >

void gtsam::EliminationTree< BAYESNET, GRAPH >::swap ( This & other )

Swap the data of this tree with another one, this operation is very fast.

Member Data Documentation

◆ roots_

template<class BAYESNET, class GRAPH>

FastVector<sharedNode> gtsam::EliminationTree< BAYESNET, GRAPH >::roots_

protected

concept check

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

/home/docs/checkouts/readthedocs.org/user_builds/gtsam-jlblanco-docs/checkouts/latest/gtsam/inference/EliminationTree.h
/home/docs/checkouts/readthedocs.org/user_builds/gtsam-jlblanco-docs/checkouts/latest/gtsam/inference/EliminationTree-inst.h

Classes

Public Types

Public Member Functions

Protected Types

Protected Attributes

Standard Constructors

Standard Interface

Testable

Advanced Interface

Detailed Description

template<class BAYESNET, class GRAPH> class gtsam::EliminationTree< BAYESNET, GRAPH >

Constructor & Destructor Documentation

◆ EliminationTree() [1/3]

◆ EliminationTree() [2/3]

◆ EliminationTree() [3/3]

◆ ~EliminationTree()

Member Function Documentation

◆ eliminate()

◆ equals()

◆ operator=()

◆ print()

◆ remainingFactors()

◆ roots()

◆ swap()

Member Data Documentation

◆ roots_

template<class BAYESNET, class GRAPH>
class gtsam::EliminationTree< BAYESNET, GRAPH >