gtsam::BayesTreeCliqueBase< DERIVED, FACTORGRAPH > Class Template Reference

Detailed Description

template<class DERIVED, class FACTORGRAPH>
class gtsam::BayesTreeCliqueBase< DERIVED, FACTORGRAPH >

This is the base class for BayesTree cliques.

The default and standard derived type is BayesTreeClique, but some algorithms, like iSAM2, use a different clique type in order to store extra data along with the clique.

This class is templated on the derived class (i.e. the curiously recursive template pattern). The advantage of this over using virtual classes is that it avoids the need for casting to get the derived type. This is possible because all cliques in a BayesTree are the same type - if they were not then we'd need a virtual class.

Template Parameters

DERIVED	The derived clique type.
CONDITIONAL	The conditional type.

Standard Constructors
	BayesTreeCliqueBase ()
	Default constructor.
	BayesTreeCliqueBase (const sharedConditional &conditional)
	Construct from a conditional, leaving parent and child pointers uninitialized.

Testable
bool	equals (const DERIVED &other, double tol=1e-9) const
	check equality
void	print (const std::string &s="", const KeyFormatter &keyFormatter=DefaultKeyFormatter) const
	print this node

Standard Interface
const sharedConditional &	conditional () const
	Access the conditional.
bool	isRoot () const
	is this the root of a Bayes tree ?
size_t	treeSize () const
	The size of subtree rooted at this clique, i.e., nr of Cliques.
size_t	numCachedSeparatorMarginals () const
	Collect number of cliques with cached separator marginals.
derived_ptr	parent () const
	return a shared_ptr to the parent clique
int	problemSize () const
	Problem size (used for parallel traversal)

Advanced Interface
class	BayesTree< DerivedType >
class	boost::serialization::access
	Serialization function.
KeyVector	separator_setminus_B (const derived_ptr &B) const
	Calculate set \( S \setminus B \) for shortcut calculations.
KeyVector	shortcut_indices (const derived_ptr &B, const FactorGraphType &p_Cp_B) const
	Determine variable indices to keep in recursive separator shortcut calculation The factor graph p_Cp_B has keys from the parent clique Cp and from B. More...
void	deleteCachedShortcutsNonRecursive ()
	Non-recursive delete cached shortcuts and marginals - internal only. More...
BayesNetType	shortcut (const derived_ptr &root, Eliminate function=EliminationTraitsType::DefaultEliminate) const
	return the conditional P(S|Root) on the separator given the root
FactorGraphType	separatorMarginal (Eliminate function=EliminationTraitsType::DefaultEliminate) const
	return the marginal P(S) on the separator
FactorGraphType	marginal2 (Eliminate function=EliminationTraitsType::DefaultEliminate) const
	return the marginal P(C) of the clique, using marginal caching
void	deleteCachedShortcuts ()
	This deletes the cached shortcuts of all cliques (subtree) below this clique. More...
const boost::optional< FactorGraphType > &	cachedSeparatorMarginal () const

Public Member Functions
void	setEliminationResult (const typename FactorGraphType::EliminationResult &eliminationResult)
	Fill the elimination result produced during elimination. More...

Public Attributes
sharedConditional	conditional_
derived_weak_ptr	parent_
FastVector< derived_ptr >	children
int	problemSize_

Public Types
typedef FACTORGRAPH	FactorGraphType
typedef EliminationTraitsType::BayesNetType	BayesNetType
typedef BayesNetType::ConditionalType	ConditionalType
typedef boost::shared_ptr< ConditionalType >	sharedConditional
typedef FactorGraphType::FactorType	FactorType
typedef FactorGraphType::Eliminate	Eliminate

Protected Attributes
boost::optional< FactorGraphType >	cachedSeparatorMarginal_
	This stores the Cached separator margnal P(S)

Member Function Documentation

deleteCachedShortcuts()

template<class DERIVED , class FACTORGRAPH >

void gtsam::BayesTreeCliqueBase< DERIVED, FACTORGRAPH >::deleteCachedShortcuts

(

)

This deletes the cached shortcuts of all cliques (subtree) below this clique.

This is performed when the bayes tree is modified.

deleteCachedShortcutsNonRecursive()

template<class DERIVED, class FACTORGRAPH>

void gtsam::BayesTreeCliqueBase< DERIVED, FACTORGRAPH >::deleteCachedShortcutsNonRecursive ( )

inlineprotected

Non-recursive delete cached shortcuts and marginals - internal only.

setEliminationResult()

template<class DERIVED , class FACTORGRAPH >

void gtsam::BayesTreeCliqueBase< DERIVED, FACTORGRAPH >::setEliminationResult

(

const typename FactorGraphType::EliminationResult &

eliminationResult

)

Fill the elimination result produced during elimination.

Here this just stores the conditional and ignores the remaining factor, but this is overridden in ISAM2Clique to also cache the remaining factor.

shortcut_indices()

template<class DERIVED , class FACTORGRAPH >

KeyVector gtsam::BayesTreeCliqueBase< DERIVED, FACTORGRAPH >::shortcut_indices ( const derived_ptr &  B, const FactorGraphType &  p_Cp_B  ) const

protected

Determine variable indices to keep in recursive separator shortcut calculation The factor graph p_Cp_B has keys from the parent clique Cp and from B.

But we only keep the variables not in S union B.

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

• /Users/dellaert/git/gtsam/gtsam/inference/BayesTreeCliqueBase.h
• /Users/dellaert/git/gtsam/gtsam/inference/BayesTreeCliqueBase-inst.h