gtsam/gtsam/inference/ISAM-inst.h

70 lines
2.3 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 <gtsam/inference/ISAM.h>
#include <gtsam/inference/VariableIndex.h>
namespace gtsam {
/* ************************************************************************* */
template<class BAYESTREE>
void ISAM<BAYESTREE>::update_internal(const FactorGraphType& newFactors,
Cliques& orphans, const Eliminate& function) {
// Remove the contaminated part of the Bayes tree
BayesNetType bn;
const KeySet newFactorKeys = newFactors.keys();
if (!this->empty()) {
std::vector<Key> keyVector(newFactorKeys.begin(), newFactorKeys.end());
this->removeTop(keyVector, bn, orphans);
}
// Add the removed top and the new factors
FactorGraphType factors;
factors += bn;
factors += newFactors;
// Add the orphaned subtrees
for (const sharedClique& orphan : orphans)
factors += boost::make_shared<BayesTreeOrphanWrapper<Clique> >(orphan);
// Get an ordering where the new keys are eliminated last
const VariableIndex index(factors);
const Ordering ordering = Ordering::ColamdConstrainedLast(index,
std::vector<Key>(newFactorKeys.begin(), newFactorKeys.end()));
// eliminate all factors (top, added, orphans) into a new Bayes tree
auto bayesTree = factors.eliminateMultifrontal(ordering, function, index);
// Re-add into Bayes tree data structures
this->roots_.insert(this->roots_.end(), bayesTree->roots().begin(),
bayesTree->roots().end());
this->nodes_.insert(bayesTree->nodes().begin(), bayesTree->nodes().end());
}
/* ************************************************************************* */
template<class BAYESTREE>
void ISAM<BAYESTREE>::update(const FactorGraphType& newFactors,
const Eliminate& function) {
Cliques orphans;
this->update_internal(newFactors, orphans, function);
}
}
/// namespace gtsam