libDAI
|
Approximate inference algorithm: implementation of single-loop ("Generalized Belief Propagation") and double-loop algorithms by Heskes, Albers and Kappen [HAK03]. More...
#include <dai/hak.h>
Classes | |
struct | Properties |
Parameters for HAK. More... | |
Public Member Functions | |
Constructors/destructors | |
HAK () | |
Default constructor. More... | |
HAK (const FactorGraph &fg, const PropertySet &opts) | |
Construct from FactorGraph fg and PropertySet opts. More... | |
HAK (const RegionGraph &rg, const PropertySet &opts) | |
Construct from RegionGraph rg and PropertySet opts. More... | |
General InfAlg interface | |
virtual HAK * | clone () const |
Returns a pointer to a new, cloned copy of *this (i.e., virtual copy constructor) More... | |
virtual HAK * | construct (const FactorGraph &fg, const PropertySet &opts) const |
Returns a pointer to a newly constructed inference algorithm. More... | |
virtual std::string | name () const |
Returns the name of the algorithm. More... | |
virtual Factor | belief (const VarSet &vs) const |
Returns the (approximate) marginal probability distribution of a set of variables. More... | |
virtual std::vector< Factor > | beliefs () const |
Returns all beliefs (approximate marginal probability distributions) calculated by the algorithm. More... | |
virtual Real | logZ () const |
Returns the logarithm of the (approximated) partition sum (normalizing constant of the factor graph). More... | |
virtual void | init () |
Initializes all data structures of the approximate inference algorithm. More... | |
virtual void | init (const VarSet &vs) |
Initializes all data structures corresponding to some set of variables. More... | |
virtual Real | run () |
Runs the approximate inference algorithm. More... | |
virtual Real | maxDiff () const |
Returns maximum difference between single variable beliefs in the last iteration. More... | |
virtual size_t | Iterations () const |
Returns number of iterations done (one iteration passes over the complete factorgraph). More... | |
virtual void | setMaxIter (size_t maxiter) |
Sets maximum number of iterations (one iteration passes over the complete factorgraph). More... | |
virtual void | setProperties (const PropertySet &opts) |
Set parameters of this inference algorithm. More... | |
virtual PropertySet | getProperties () const |
Returns parameters of this inference algorithm converted into a PropertySet. More... | |
virtual std::string | printProperties () const |
Returns parameters of this inference algorithm formatted as a string in the format "[key1=val1,key2=val2,...,keyn=valn]". More... | |
Additional interface specific for HAK | |
Factor & | muab (size_t alpha, size_t _beta) |
Returns reference to message from outer region alpha to its _beta 'th neighboring inner region. More... | |
Factor & | muba (size_t alpha, size_t _beta) |
Returns reference to message the _beta 'th neighboring inner region of outer region alpha to that outer region. More... | |
const Factor & | Qa (size_t alpha) const |
Returns belief of outer region alpha. More... | |
const Factor & | Qb (size_t beta) const |
Returns belief of inner region beta. More... | |
Real | doGBP () |
Runs single-loop algorithm (algorithm 1 in [HAK03]) More... | |
Real | doDoubleLoop () |
Runs double-loop algorithm (as described in section 4.2 of [HAK03]), which always convergences. More... | |
Public Member Functions inherited from dai::DAIAlg< GRM > | |
DAIAlg () | |
Default constructor. More... | |
DAIAlg (const GRM &grm) | |
Construct from GRM. More... | |
FactorGraph & | fg () |
Returns reference to underlying FactorGraph. More... | |
const FactorGraph & | fg () const |
Returns constant reference to underlying FactorGraph. More... | |
void | clamp (size_t i, size_t x, bool backup=false) |
Clamp variable with index i to value x (i.e. multiply with a Kronecker delta ) More... | |
void | makeCavity (size_t i, bool backup=false) |
Sets all factors interacting with variable with index i to one. More... | |
void | makeRegionCavity (std::vector< size_t > facInds, bool backup) |
Sets all factors indicated by facInds to one. More... | |
void | backupFactor (size_t I) |
Make a backup copy of factor I. More... | |
void | backupFactors (const VarSet &vs) |
Make backup copies of all factors involving the variables in vs. More... | |
void | restoreFactor (size_t I) |
Restore factor I from its backup copy. More... | |
void | restoreFactors (const VarSet &vs) |
Restore the factors involving the variables in vs from their backup copies. More... | |
void | restoreFactors () |
Restore all factors from their backup copies. More... | |
Public Member Functions inherited from dai::InfAlg | |
virtual | ~InfAlg () |
Virtual destructor (needed because this class contains virtual functions) More... | |
virtual std::string | identify () const |
Identifies itself for logging purposes. More... | |
virtual Factor | belief (const Var &v) const |
Returns the (approximate) marginal probability distribution of a variable. More... | |
virtual Factor | beliefV (size_t i) const |
Returns the (approximate) marginal probability distribution of the variable with index i. More... | |
virtual Factor | beliefF (size_t I) const |
Returns the (approximate) marginal probability distribution of the variables on which factor I depends. More... | |
virtual std::vector< size_t > | findMaximum () const |
Calculates the joint state of all variables that has maximum probability. More... | |
Public Attributes | |
struct dai::HAK::Properties | props |
Private Member Functions | |
void | construct () |
Helper function for constructors. More... | |
void | findLoopClusters (const FactorGraph &fg, std::set< VarSet > &allcl, VarSet newcl, const Var &root, size_t length, VarSet vars) |
Recursive procedure for finding clusters of variables containing loops of length at most length. More... | |
Private Attributes | |
std::vector< Factor > | _Qa |
Outer region beliefs. More... | |
std::vector< Factor > | _Qb |
Inner region beliefs. More... | |
std::vector< std::vector< Factor > > | _muab |
Messages from outer to inner regions. More... | |
std::vector< std::vector< Factor > > | _muba |
Messages from inner to outer regions. More... | |
Real | _maxdiff |
Maximum difference encountered so far. More... | |
size_t | _iters |
Number of iterations needed. More... | |
Approximate inference algorithm: implementation of single-loop ("Generalized Belief Propagation") and double-loop algorithms by Heskes, Albers and Kappen [HAK03].
|
inline |
Default constructor.
dai::HAK::HAK | ( | const FactorGraph & | fg, |
const PropertySet & | opts | ||
) |
Construct from FactorGraph fg and PropertySet opts.
fg | Factor graph. |
opts | Parameters |
dai::HAK::HAK | ( | const RegionGraph & | rg, |
const PropertySet & | opts | ||
) |
Construct from RegionGraph rg and PropertySet opts.
|
inlinevirtual |
Returns a pointer to a new, cloned copy of *this
(i.e., virtual copy constructor)
Implements dai::InfAlg.
|
inlinevirtual |
Returns a pointer to a newly constructed inference algorithm.
fg | Factor graph on which to perform the inference algorithm; |
opts | Parameters passed to constructor of inference algorithm; |
Implements dai::InfAlg.
|
inlinevirtual |
Returns the name of the algorithm.
Implements dai::InfAlg.
Returns the (approximate) marginal probability distribution of a set of variables.
NOT_IMPLEMENTED | if not implemented/supported. |
BELIEF_NOT_AVAILABLE | if the requested belief cannot be calculated with this algorithm. |
Implements dai::InfAlg.
|
virtual |
Returns all beliefs (approximate marginal probability distributions) calculated by the algorithm.
Implements dai::InfAlg.
|
virtual |
Returns the logarithm of the (approximated) partition sum (normalizing constant of the factor graph).
NOT_IMPLEMENTED | if not implemented/supported |
Implements dai::InfAlg.
|
virtual |
Initializes all data structures of the approximate inference algorithm.
Implements dai::InfAlg.
|
virtual |
Initializes all data structures corresponding to some set of variables.
This method can be used to do a partial initialization after a part of the factor graph has changed. Instead of initializing all data structures, it only initializes those involving the variables in vs.
NOT_IMPLEMENTED | if not implemented/supported |
Implements dai::InfAlg.
|
virtual |
Runs the approximate inference algorithm.
Implements dai::InfAlg.
|
inlinevirtual |
Returns maximum difference between single variable beliefs in the last iteration.
NOT_IMPLEMENTED | if not implemented/supported |
Reimplemented from dai::InfAlg.
|
inlinevirtual |
Returns number of iterations done (one iteration passes over the complete factorgraph).
NOT_IMPLEMENTED | if not implemented/supported |
Reimplemented from dai::InfAlg.
|
inlinevirtual |
Sets maximum number of iterations (one iteration passes over the complete factorgraph).
NOT_IMPLEMENTED | if not implemented/supported |
Reimplemented from dai::InfAlg.
|
virtual |
Set parameters of this inference algorithm.
The parameters are set according to the PropertySet opts. The values can be stored either as std::string or as the type of the corresponding MF::props member.
Implements dai::InfAlg.
|
virtual |
Returns parameters of this inference algorithm converted into a PropertySet.
Implements dai::InfAlg.
|
virtual |
Returns parameters of this inference algorithm formatted as a string in the format "[key1=val1,key2=val2,...,keyn=valn]".
Implements dai::InfAlg.
|
inline |
Returns reference to message from outer region alpha to its _beta 'th neighboring inner region.
|
inline |
Returns reference to message the _beta 'th neighboring inner region of outer region alpha to that outer region.
|
inline |
Returns belief of outer region alpha.
|
inline |
Returns belief of inner region beta.
Real dai::HAK::doDoubleLoop | ( | ) |
Runs double-loop algorithm (as described in section 4.2 of [HAK03]), which always convergences.
|
private |
Helper function for constructors.
|
private |
Recursive procedure for finding clusters of variables containing loops of length at most length.
fg | the factor graph |
allcl | the clusters found so far |
newcl | partial candidate cluster |
root | start (and end) point of the loop |
length | number of variables that may be added to newcl |
vars | neighboring variables of newcl |
|
private |
Outer region beliefs.
|
private |
Inner region beliefs.
|
private |
Messages from outer to inner regions.
|
private |
Messages from inner to outer regions.
|
private |
Maximum difference encountered so far.
|
private |
Number of iterations needed.