gtsam/cpp/FactorGraph.h

117 lines
3.0 KiB
C++

/**
* @file FactorGraph.h
* @brief Factor Graph Base Class
* @author Carlos Nieto
* @author Christian Potthast
*/
// \callgraph
#pragma once
#include <boost/shared_ptr.hpp>
#include <boost/serialization/map.hpp>
#include <boost/serialization/vector.hpp>
#include <boost/serialization/shared_ptr.hpp>
#include "Testable.h"
namespace gtsam {
class Ordering;
/**
* A factor graph is a bipartite graph with factor nodes connected to variable nodes.
* In this class, however, only factor nodes are kept around.
*
* Templated on the type of factors and configuration.
*/
template<class Factor> class FactorGraph: public Testable<FactorGraph<Factor> > {
public:
typedef typename boost::shared_ptr<Factor> shared_factor;
typedef typename std::vector<shared_factor>::iterator iterator;
typedef typename std::vector<shared_factor>::const_iterator const_iterator;
protected:
/** Collection of factors */
std::vector<shared_factor> factors_;
/** For each variable a list of factor indices connected to it */
typedef std::map<std::string, std::list<int> > Indices;
Indices indices_;
public:
/** print out graph */
void print(const std::string& s = "FactorGraph") const;
/** Check equality */
bool equals(const FactorGraph& fg, double tol = 1e-9) const;
/** STL like, return the iterator pointing to the first factor */
inline const_iterator begin() const {
return factors_.begin();
}
/** STL like, return the iterator pointing to the last factor */
inline const_iterator end() const {
return factors_.end();
}
/** clear the factor graph */
inline void clear() {
factors_.clear();
}
/** Get a specific factor by index */
inline shared_factor operator[](size_t i) const {
return factors_[i];
}
/** return the number of factors and NULLS */
inline size_t size() const { return factors_.size();}
/** return the number valid factors */
size_t nrFactors() const;
/** Add a factor */
void push_back(shared_factor factor);
/**
* Compute colamd ordering
*/
Ordering getOrdering() const;
/**
* Return indices for all factors that involve the given node
* @param key the key for the given node
*/
std::list<int> factors(const std::string& key) const;
/**
* find all the factors that involve the given node and remove them
* from the factor graph
* @param key the key for the given node
*/
std::vector<shared_factor> findAndRemoveFactors(const std::string& key);
/**
* extract and combine all the factors that involve a given node
* @param key the key for the given node
* @return the combined linear factor
*/
shared_factor removeAndCombineFactors(const std::string& key);
private:
/** Serialization function */
friend class boost::serialization::access;
template<class Archive>
void serialize(Archive & ar, const unsigned int version) {
ar & BOOST_SERIALIZATION_NVP(factors_);
ar & BOOST_SERIALIZATION_NVP(indices_);
}
}; // FactorGraph
} // namespace gtsam