code cleanup, recovering estimate while dealing with incremental adding of factors, planar with new SLAM

release/4.3a0
Michael Kaess 2010-01-18 04:32:45 +00:00
parent 9ac1622514
commit 42f4ff228b
3 changed files with 84 additions and 116 deletions

View File

@ -23,7 +23,7 @@ namespace gtsam {
using namespace std;
// from inference-inl.h - need to additionally return the newly created factor for caching
boost::shared_ptr<GaussianConditional> _eliminateOne(FactorGraph<GaussianFactor>& graph, cachedFactors& cached, const Symbol& key) {
boost::shared_ptr<GaussianConditional> _eliminateOne(FactorGraph<GaussianFactor>& graph, cachedFactors& cached, const string& key) {
// combine the factors of all nodes connected to the variable to be eliminated
// if no factors are connected to key, returns an empty factor
@ -47,7 +47,7 @@ namespace gtsam {
// from GaussianFactorGraph.cpp, see _eliminateOne above
GaussianBayesNet _eliminate(FactorGraph<GaussianFactor>& graph, cachedFactors& cached, const Ordering& ordering) {
GaussianBayesNet chordalBayesNet; // empty
BOOST_FOREACH(const Symbol& key, ordering) {
BOOST_FOREACH(string key, ordering) {
GaussianConditional::shared_ptr cg = _eliminateOne(graph, cached, key);
chordalBayesNet.push_back(cg);
}
@ -72,6 +72,43 @@ namespace gtsam {
_eliminate_const(nlfg.linearize(config), cached, ordering);
}
/* ************************************************************************* */
// retrieve all factors that ONLY contain the affected variables
// (note that the remaining stuff is summarized in the cached factors)
template<class Conditional, class Config>
FactorGraph<GaussianFactor> ISAM2<Conditional, Config>::relinearizeAffectedFactors(const list<string>& affectedKeys) {
NonlinearFactorGraph<Config> nonlinearAffectedFactors;
typename FactorGraph<NonlinearFactor<Config> >::iterator it;
for(it = nonlinearFactors_.begin(); it != nonlinearFactors_.end(); it++) {
bool inside = true;
BOOST_FOREACH(string key, (*it)->keys()) {
if (find(affectedKeys.begin(), affectedKeys.end(), key) == affectedKeys.end())
inside = false;
}
if (inside)
nonlinearAffectedFactors.push_back(*it);
}
return nonlinearAffectedFactors.linearize(config_);
}
/* ************************************************************************* */
template<class Conditional, class Config>
FactorGraph<GaussianFactor> ISAM2<Conditional, Config>::getCachedBoundaryFactors(Cliques& orphans) {
// add intermediate (linearized) factors from cache that are passed into the affected area
FactorGraph<GaussianFactor> cachedBoundary;
BOOST_FOREACH(sharedClique orphan, orphans) {
// find the last variable that is not part of the separator
string oneTooFar = orphan->separator_.front();
list<string> keys = orphan->keys();
list<string>::iterator it = find(keys.begin(), keys.end(), oneTooFar);
it--;
string key = *it;
// retrieve the cached factor and add to boundary
cachedBoundary.push_back(cached[key]);
}
return cachedBoundary;
}
/* ************************************************************************* */
template<class Conditional, class Config>
void ISAM2<Conditional, Config>::update_internal(const NonlinearFactorGraph<Config>& newFactors,
@ -90,125 +127,31 @@ namespace gtsam {
FactorGraph<GaussianFactor> affectedFactors;
boost::tie(affectedFactors, orphans) = this->removeTop(newFactorsLinearized);
#if 1
#if 0
// find the corresponding original nonlinear factors, and relinearize them
NonlinearFactorGraph<Config> nonlinearAffectedFactors;
set<int> idxs; // avoid duplicates by putting index into set
BOOST_FOREACH(FactorGraph<GaussianFactor>::sharedFactor fac, affectedFactors) {
// retrieve correspondent factor from nonlinearFactors_
Ordering keys = fac->keys();
BOOST_FOREACH(const Symbol& key, keys) {
list<int> indices = nonlinearFactors_.factors(key);
BOOST_FOREACH(int idx, indices) {
// todo - only insert index if factor is subset of keys... not needed once we do relinearization - but then how to deal with overlap with orphans?
bool subset = true;
BOOST_FOREACH(const Symbol& k, nonlinearFactors_[idx]->keys()) {
if (find(keys.begin(), keys.end(), k)==keys.end()) subset = false;
}
if (subset) {
idxs.insert(idx);
}
}
}
}
BOOST_FOREACH(int idx, idxs) {
nonlinearAffectedFactors.push_back(nonlinearFactors_[idx]);
}
// relinearize the affected factors ...
list<string> affectedKeys = affectedFactors.keys();
FactorGraph<GaussianFactor> factors = relinearizeAffectedFactors(affectedKeys);
FactorGraph<GaussianFactor> factors = nonlinearAffectedFactors.linearize(config_);
#else
NonlinearFactorGraph<Config> nonlinearAffectedFactors;
// retrieve all factors that ONLY contain the affected variables
// (note that the remaining stuff is summarized in the cached factors)
list<Symbol> affectedKeys = affectedFactors.keys();
typename FactorGraph<NonlinearFactor<Config> >::iterator it;
for(it = nonlinearFactors_.begin(); it != nonlinearFactors_.end(); it++) {
bool inside = true;
BOOST_FOREACH(string key, (*it)->keys()) {
if (find(affectedKeys.begin(), affectedKeys.end(), key) == affectedKeys.end())
inside = false;
}
if (inside)
nonlinearAffectedFactors.push_back(*it);
}
FactorGraph<GaussianFactor> factors = nonlinearAffectedFactors.linearize(config_);
// recover intermediate factors from cache that are passed into the affected area
FactorGraph<GaussianFactor> cachedBoundary;
BOOST_FOREACH(sharedClique orphan, orphans) {
// find the last variable that is not part of the separator
string oneTooFar = orphan->separator_.front();
list<Symbol> keys = orphan->keys();
list<Symbol>::iterator it = find(keys.begin(), keys.end(), oneTooFar);
it--;
const Symbol& key = *it;
// retrieve the cached factor and add to boundary
cachedBoundary.push_back(cached[key]);
}
// ... add the cached intermediate results from the boundary of the orphans ...
FactorGraph<GaussianFactor> cachedBoundary = getCachedBoundaryFactors(orphans);
factors.push_back(cachedBoundary);
#endif
#if 0
printf("**************\n");
nonlinearFactors_.linearize(config).print("all factors");
printf("--------------\n");
newFactorsLinearized.print("newFactorsLinearized");
printf("--------------\n");
factors.print("factors");
printf("--------------\n");
affectedFactors.print("affectedFactors");
printf("--------------\n");
#endif
// add the new factors themselves
// ... and finally add the new linearized factors themselves
factors.push_back(newFactorsLinearized);
#endif
// create an ordering for the new and contaminated factors
Ordering ordering;
if (true) {
ordering = factors.getOrdering();
} else {
list<Symbol> keys = factors.keys();
list<string> keys = factors.keys();
keys.sort(); // todo: correct sorting order?
ordering = keys;
}
#if 0
ordering.print();
factors.print("factors BEFORE");
printf("--------------\n");
#endif
// eliminate into a Bayes net
BayesNet<Conditional> bayesNet = _eliminate(factors, cached, ordering);
#if 1
// check if relinearized agrees with correct solution
affectedFactors.push_back(newFactorsLinearized);
#if 0
affectedFactors.print("affectedFactors BEFORE");
printf("--------------\n");
#endif
BayesNet<Conditional> bayesNetTest = eliminate<GaussianFactor, GaussianConditional>(affectedFactors, ordering);
if (!bayesNet.equals(bayesNetTest)) {
printf("differ\n");
bayesNet.print();
bayesNetTest.print();
exit(42);
}
#endif
// remember the new factors for later relinearization
nonlinearFactors_.push_back(newFactors);
// insert conditionals back in, straight into the topless bayesTree
@ -216,29 +159,25 @@ namespace gtsam {
for ( rit=bayesNet.rbegin(); rit != bayesNet.rend(); ++rit )
this->insert(*rit);
int count = 0;
// add orphans to the bottom of the new tree
BOOST_FOREACH(sharedClique orphan, orphans) {
Symbol key = orphan->separator_.front();
string key = orphan->separator_.front();
sharedClique parent = (*this)[key];
parent->children_ += orphan;
orphan->parent_ = parent; // set new parent!
}
// update solution
VectorConfig solution = optimize2(*this);
solution.print();
}
template<class Conditional, class Config>
void ISAM2<Conditional, Config>::update(const NonlinearFactorGraph<Config>& newFactors, const Config& config) {
#if 0
printf("8888888888888888\n");
try {
this->print("BayesTree");
} catch (char * c) {};
printf("8888888888888888\n");
#endif
Cliques orphans;
this->update_internal(newFactors, config, orphans);
}

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@ -31,8 +31,13 @@ namespace gtsam {
protected:
// for keeping all original nonlinear data
Config config_;
// current linearization point
Config linPoint_;
// most recent estimate
Config estimate_;
// for keeping all original nonlinear factors
NonlinearFactorGraph<Config> nonlinearFactors_;
// cached intermediate results for restarting computation in the middle
@ -60,6 +65,12 @@ namespace gtsam {
void update_internal(const NonlinearFactorGraph<Config>& newFactors, const Config& config, Cliques& orphans);
void update(const NonlinearFactorGraph<Config>& newFactors, const Config& config);
const Config estimate() {return estimate_;}
private:
FactorGraph<GaussianFactor> relinearizeAffectedFactors(const std::list<Symbol>& affectedKeys);
FactorGraph<GaussianFactor> getCachedBoundaryFactors(Cliques& orphans);
}; // ISAM2
} /// namespace gtsam

View File

@ -21,6 +21,24 @@ using namespace boost::assign;
using namespace std;
using namespace gtsam;
/* ************************************************************************* */
TEST( ISAM2, solving )
{
ExampleNonlinearFactorGraph nlfg = createNonlinearFactorGraph();
VectorConfig noisy = createNoisyConfig();
Ordering ordering;
ordering += symbol('x', 1);
ordering += symbol('x', 2);
ordering += symbol('l', 1);
GaussianISAM2 btree(nlfg, ordering, noisy);
VectorConfig actualDelta = optimize2(btree);
VectorConfig delta = createCorrectDelta();
CHECK(assert_equal(delta, actualDelta));
VectorConfig actualSolution = noisy+actualDelta;
VectorConfig solution = createConfig();
CHECK(assert_equal(solution, actualSolution));
}
/* ************************************************************************* */
TEST( ISAM2, ISAM2_smoother )
{