gtsam/inference/ISAM-inl.h

78 lines
2.2 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 ISAM-inl.h
* @brief Incremental update functionality (iSAM) for BayesTree.
* @author Michael Kaess
*/
#pragma once
#include <boost/foreach.hpp>
#include <boost/assign/std/list.hpp> // for operator +=
using namespace boost::assign;
#include <gtsam/inference/Conditional.h>
#include <gtsam/inference/ISAM.h>
#include <gtsam/inference/BayesTree-inl.h>
namespace gtsam {
using namespace std;
/** Create an empty Bayes Tree */
template<class CONDITIONAL>
ISAM<CONDITIONAL>::ISAM() : BayesTree<CONDITIONAL>() {}
/** Create a Bayes Tree from a Bayes Net */
template<class CONDITIONAL>
ISAM<CONDITIONAL>::ISAM(const BayesNet<CONDITIONAL>& bayesNet) :
BayesTree<CONDITIONAL>(bayesNet) {}
/* ************************************************************************* */
template<class CONDITIONAL>
template<class FACTORGRAPH>
void ISAM<CONDITIONAL>::update_internal(const FACTORGRAPH& newFactors, Cliques& orphans) {
// Remove the contaminated part of the Bayes tree
BayesNet<CONDITIONAL> bn;
removeTop(newFactors.keys(), bn, orphans);
FACTORGRAPH factors(bn);
// add the factors themselves
factors.push_back(newFactors);
// eliminate into a Bayes net
typename BayesNet<CONDITIONAL>::shared_ptr bayesNet = Inference::Eliminate(factors);
// insert conditionals back in, straight into the topless bayesTree
typename BayesNet<CONDITIONAL>::const_reverse_iterator rit;
for ( rit=bayesNet->rbegin(); rit != bayesNet->rend(); ++rit )
this->insert(*rit);
// add orphans to the bottom of the new tree
BOOST_FOREACH(sharedClique orphan, orphans) {
this->insert(orphan);
}
}
template<class CONDITIONAL>
template<class FACTORGRAPH>
void ISAM<CONDITIONAL>::update(const FACTORGRAPH& newFactors) {
Cliques orphans;
this->update_internal(newFactors, orphans);
}
}
/// namespace gtsam