gtsam/gtsam/inference/FactorGraph.h

354 lines
12 KiB
C++

/* ----------------------------------------------------------------------------
* GTSAM Copyright 2010, Georgia Tech Research Corporation,
* Atlanta, Georgia 30332-0415
* All Rights Reserved
* Authors: Frank Dellaert, et al. (see THANKS for the full author list)
* See LICENSE for the license information
* -------------------------------------------------------------------------- */
/**
* @file FactorGraph.h
* @brief Factor Graph Base Class
* @author Carlos Nieto
* @author Christian Potthast
* @author Michael Kaess
* @author Richard Roberts
*/
// \callgraph
#pragma once
#include <boost/serialization/nvp.hpp>
#include <boost/assign/list_inserter.hpp>
#include <boost/bind.hpp>
#include <boost/make_shared.hpp>
#include <boost/utility/enable_if.hpp>
#include <boost/type_traits.hpp>
#include <gtsam/base/Testable.h>
#include <gtsam/base/FastVector.h>
#include <gtsam/inference/Key.h>
namespace gtsam {
// Forward declarations
template<class CLIQUE> class BayesTree;
/** Helper */
template<class C>
class CRefCallPushBack
{
C& obj;
public:
CRefCallPushBack(C& obj) : obj(obj) {}
template<typename A>
void operator()(const A& a) { obj.push_back(a); }
};
/** Helper */
template<class C>
class RefCallPushBack
{
C& obj;
public:
RefCallPushBack(C& obj) : obj(obj) {}
template<typename A>
void operator()(A& a) { obj.push_back(a); }
};
/** Helper */
template<class C>
class CRefCallAddCopy
{
C& obj;
public:
CRefCallAddCopy(C& obj) : obj(obj) {}
template<typename A>
void operator()(const A& a) { obj.addCopy(a); }
};
/**
* A factor graph is a bipartite graph with factor nodes connected to variable nodes.
* In this class, however, only factor nodes are kept around.
* \nosubgrouping
*/
template<class FACTOR>
class FactorGraph {
public:
typedef FACTOR FactorType; ///< factor type
typedef boost::shared_ptr<FACTOR> sharedFactor; ///< Shared pointer to a factor
typedef sharedFactor value_type;
typedef typename FastVector<sharedFactor>::iterator iterator;
typedef typename FastVector<sharedFactor>::const_iterator const_iterator;
private:
typedef FactorGraph<FACTOR> This; ///< Typedef for this class
typedef boost::shared_ptr<This> shared_ptr; ///< Shared pointer for this class
protected:
/** concept check, makes sure FACTOR defines print and equals */
GTSAM_CONCEPT_TESTABLE_TYPE(FACTOR)
/** Collection of factors */
FastVector<sharedFactor> factors_;
/// @name Standard Constructors
/// @{
/** Default constructor */
FactorGraph() {}
/** Constructor from iterator over factors (shared_ptr or plain objects) */
template<typename ITERATOR>
FactorGraph(ITERATOR firstFactor, ITERATOR lastFactor) { push_back(firstFactor, lastFactor); }
/** Construct from container of factors (shared_ptr or plain objects) */
template<class CONTAINER>
explicit FactorGraph(const CONTAINER& factors) { push_back(factors); }
/// @}
/// @name Advanced Constructors
/// @{
// TODO: are these needed?
///**
// * @brief Constructor from a Bayes net
// * @param bayesNet the Bayes net to convert, type CONDITIONAL must yield compatible factor
// * @return a factor graph with all the conditionals, as factors
// */
//template<class CONDITIONAL>
//FactorGraph(const BayesNet<CONDITIONAL>& bayesNet);
///** convert from Bayes tree */
//template<class CONDITIONAL, class CLIQUE>
//FactorGraph(const BayesTree<CONDITIONAL, CLIQUE>& bayesTree);
///** convert from a derived type */
//template<class DERIVEDFACTOR>
//FactorGraph(const FactorGraph<DERIVEDFACTOR>& factors) {
// factors_.assign(factors.begin(), factors.end());
//}
/// @}
public:
/// @name Adding Factors
/// @{
/**
* Reserve space for the specified number of factors if you know in
* advance how many there will be (works like FastVector::reserve).
*/
void reserve(size_t size) { factors_.reserve(size); }
// TODO: are these needed?
/** Add a factor directly using a shared_ptr */
template<class DERIVEDFACTOR>
typename boost::enable_if<boost::is_base_of<FactorType, DERIVEDFACTOR> >::type
push_back(boost::shared_ptr<DERIVEDFACTOR> factor) {
factors_.push_back(boost::shared_ptr<FACTOR>(factor)); }
/** Add a factor directly using a shared_ptr */
void push_back(const sharedFactor& factor) {
factors_.push_back(factor); }
/** push back many factors with an iterator over shared_ptr (factors are not copied) */
template<typename ITERATOR>
typename boost::enable_if<boost::is_base_of<FactorType, typename ITERATOR::value_type::element_type> >::type
push_back(ITERATOR firstFactor, ITERATOR lastFactor) {
factors_.insert(end(), firstFactor, lastFactor); }
/** push back many factors as shared_ptr's in a container (factors are not copied) */
template<typename CONTAINER>
typename boost::enable_if<boost::is_base_of<FactorType, typename CONTAINER::value_type::element_type> >::type
push_back(const CONTAINER& container) {
push_back(container.begin(), container.end());
}
/** push back a BayesTree as a collection of factors. NOTE: This should be hidden in derived
* classes in favor of a type-specialized version that calls this templated function. */
template<class CLIQUE>
typename boost::enable_if<boost::is_base_of<This, typename CLIQUE::FactorGraphType> >::type
push_back(const BayesTree<CLIQUE>& bayesTree) {
bayesTree.addFactorsToGraph(*this);
}
/** Add a factor by value, will be copy-constructed (use push_back with a shared_ptr to avoid
* the copy). */
template<class DERIVEDFACTOR>
typename boost::enable_if<boost::is_base_of<FactorType, DERIVEDFACTOR> >::type
push_back(const DERIVEDFACTOR& factor) {
factors_.push_back(boost::make_shared<DERIVEDFACTOR>(factor));
}
/** push back many factors with an iterator over plain factors (factors are copied) */
template<typename ITERATOR>
typename boost::enable_if<boost::is_base_of<FactorType, typename ITERATOR::value_type> >::type
push_back(ITERATOR firstFactor, ITERATOR lastFactor) {
for (ITERATOR f = firstFactor; f != lastFactor; ++f)
push_back(*f);
}
/** push back many factors as non-pointer objects in a container (factors are copied) */
template<typename CONTAINER>
typename boost::enable_if<boost::is_base_of<FactorType, typename CONTAINER::value_type> >::type
push_back(const CONTAINER& container) {
push_back(container.begin(), container.end());
}
/** Add a factor directly using a shared_ptr */
template<class DERIVEDFACTOR>
typename boost::enable_if<boost::is_base_of<FactorType, DERIVEDFACTOR>,
boost::assign::list_inserter<RefCallPushBack<This> > >::type
operator+=(boost::shared_ptr<DERIVEDFACTOR> factor) {
return boost::assign::make_list_inserter(RefCallPushBack<This>(*this))(factor);
}
/** Add a factor directly using a shared_ptr */
boost::assign::list_inserter<CRefCallPushBack<This> >
operator+=(const sharedFactor& factor) {
return boost::assign::make_list_inserter(CRefCallPushBack<This>(*this))(factor);
}
/** Add a factor or container of factors, including STL collections, BayesTrees, etc. */
template<class FACTOR_OR_CONTAINER>
boost::assign::list_inserter<CRefCallPushBack<This> >
operator+=(const FACTOR_OR_CONTAINER& factorOrContainer) {
return boost::assign::make_list_inserter(CRefCallPushBack<This>(*this))(factorOrContainer);
}
/** Add a factor directly using a shared_ptr */
template<class DERIVEDFACTOR>
typename boost::enable_if<boost::is_base_of<FactorType, DERIVEDFACTOR> >::type
add(boost::shared_ptr<DERIVEDFACTOR> factor) {
push_back(factor);
}
/** Add a factor directly using a shared_ptr */
void add(const sharedFactor& factor) {
push_back(factor);
}
/** Add a factor or container of factors, including STL collections, BayesTrees, etc. */
template<class FACTOR_OR_CONTAINER>
void add(const FACTOR_OR_CONTAINER& factorOrContainer) {
push_back(factorOrContainer);
}
/// @}
/// @name Testable
/// @{
/** print out graph */
void print(const std::string& s = "FactorGraph",
const KeyFormatter& formatter = DefaultKeyFormatter) const;
/** Check equality */
bool equals(const This& fg, double tol = 1e-9) const;
/// @}
public:
/// @name Standard Interface
/// @{
/** return the number of factors (including any null factors set by remove() ). */
size_t size() const { return factors_.size(); }
/** Check if the graph is empty (null factors set by remove() will cause this to return false). */
bool empty() const { return factors_.empty(); }
/** Get a specific factor by index (this checks array bounds and may throw an exception, as
* opposed to operator[] which does not).
*/
const sharedFactor at(size_t i) const { return factors_.at(i); }
/** Get a specific factor by index (this checks array bounds and may throw an exception, as
* opposed to operator[] which does not).
*/
sharedFactor& at(size_t i) { return factors_.at(i); }
/** Get a specific factor by index (this does not check array bounds, as opposed to at() which
* does).
*/
const sharedFactor operator[](size_t i) const { return at(i); }
/** Get a specific factor by index (this does not check array bounds, as opposed to at() which
* does).
*/
sharedFactor& operator[](size_t i) { return at(i); }
/** Iterator to beginning of factors. */
const_iterator begin() const { return factors_.begin();}
/** Iterator to end of factors. */
const_iterator end() const { return factors_.end(); }
/** Get the first factor */
sharedFactor front() const { return factors_.front(); }
/** Get the last factor */
sharedFactor back() const { return factors_.back(); }
/// @}
/// @name Modifying Factor Graphs (imperative, discouraged)
/// @{
/** non-const STL-style begin() */
iterator begin() { return factors_.begin();}
/** non-const STL-style end() */
iterator end() { return factors_.end(); }
/** Directly resize the number of factors in the graph. If the new size is less than the
* original, factors at the end will be removed. If the new size is larger than the original,
* null factors will be appended.
*/
void resize(size_t size) { factors_.resize(size); }
/** delete factor without re-arranging indexes by inserting a NULL pointer */
void remove(size_t i) { factors_[i].reset();}
/** replace a factor by index */
void replace(size_t index, sharedFactor factor) { at(index) = factor; }
/** Erase factor and rearrange other factors to take up the empty space */
void erase(iterator item) { factors_.erase(item); }
/** Erase factors and rearrange other factors to take up the empty space */
void erase(iterator first, iterator last) { factors_.erase(first, last); }
/// @}
/// @name Advanced Interface
/// @{
/** return the number of non-null factors */
size_t nrFactors() const;
/** Potentially very slow function to return all keys involved */
FastSet<Key> keys() const;
/** MATLAB interface utility: Checks whether a factor index idx exists in the graph and is a live pointer */
inline bool exists(size_t idx) const { return idx < size() && at(idx); }
private:
/** Serialization function */
friend class boost::serialization::access;
template<class ARCHIVE>
void serialize(ARCHIVE & ar, const unsigned int /*version*/) {
ar & BOOST_SERIALIZATION_NVP(factors_);
}
/// @}
}; // FactorGraph
} // namespace gtsam