gtsam/gtsam/discrete/DiscreteFactor.h

110 lines
3.2 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 DiscreteFactor.h
* @date Feb 14, 2011
* @author Duy-Nguyen Ta
* @author Frank Dellaert
*/
#pragma once
#include <gtsam/discrete/Assignment.h>
#include <gtsam/inference/Factor.h>
#include <gtsam/base/Testable.h>
namespace gtsam {
class DecisionTreeFactor;
class DiscreteConditional;
/**
* Base class for discrete probabilistic factors
* The most general one is the derived DecisionTreeFactor
*/
class GTSAM_EXPORT DiscreteFactor: public Factor {
public:
// typedefs needed to play nice with gtsam
typedef DiscreteFactor This; ///< This class
typedef boost::shared_ptr<DiscreteFactor> shared_ptr; ///< shared_ptr to this class
typedef Factor Base; ///< Our base class
/** A map from keys to values
* TODO: Do we need this? Should we just use gtsam::Values?
* We just need another special DiscreteValue to represent labels,
* However, all other Lie's operators are undefined in this class.
* The good thing is we can have a Hybrid graph of discrete/continuous variables
* together..
* Another good thing is we don't need to have the special DiscreteKey which stores
* cardinality of a Discrete variable. It should be handled naturally in
* the new class DiscreteValue, as the varible's type (domain)
*/
typedef Assignment<Key> Values;
typedef boost::shared_ptr<Values> sharedValues;
public:
/// @name Standard Constructors
/// @{
/** Default constructor creates empty factor */
DiscreteFactor() {}
/** Construct from container of keys. This constructor is used internally from derived factor
* constructors, either from a container of keys or from a boost::assign::list_of. */
template<typename CONTAINER>
DiscreteFactor(const CONTAINER& keys) : Base(keys) {}
/// Virtual destructor
virtual ~DiscreteFactor() {
}
/// @}
/// @name Testable
/// @{
// equals
virtual bool equals(const DiscreteFactor& lf, double tol = 1e-9) const = 0;
// print
virtual void print(const std::string& s = "DiscreteFactor\n",
const KeyFormatter& formatter = DefaultKeyFormatter) const {
Factor::print(s, formatter);
}
/** Test whether the factor is empty */
virtual bool empty() const { return size() == 0; }
/// @}
/// @name Standard Interface
/// @{
/// Find value for given assignment of values to variables
virtual double operator()(const Values&) const = 0;
/// Multiply in a DecisionTreeFactor and return the result as DecisionTreeFactor
virtual DecisionTreeFactor operator*(const DecisionTreeFactor&) const = 0;
virtual DecisionTreeFactor toDecisionTreeFactor() const = 0;
/// @}
};
// DiscreteFactor
// traits
template<> struct traits<DiscreteFactor> : public Testable<DiscreteFactor> {};
template<> struct traits<DiscreteFactor::Values> : public Testable<DiscreteFactor::Values> {};
}// namespace gtsam