gtsam/gtsam/nonlinear/NonlinearFactorGraph.cpp

343 lines
12 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 NonlinearFactorGraph.cpp
* @brief Factor Graph Consisting of non-linear factors
* @author Frank Dellaert
* @author Carlos Nieto
* @author Christian Potthast
*/
#include <cmath>
#include <limits>
#include <boost/foreach.hpp>
#include <gtsam/inference/FactorGraph.h>
#include <gtsam/inference/inference.h>
#include <gtsam/geometry/Pose2.h>
#include <gtsam/geometry/Pose3.h>
#include <gtsam/nonlinear/NonlinearFactorGraph.h>
using namespace std;
namespace gtsam {
/* ************************************************************************* */
double NonlinearFactorGraph::probPrime(const Values& c) const {
return exp(-0.5 * error(c));
}
/* ************************************************************************* */
void NonlinearFactorGraph::print(const std::string& str, const KeyFormatter& keyFormatter) const {
cout << str << "size: " << size() << endl;
for (size_t i = 0; i < factors_.size(); i++) {
stringstream ss;
ss << "factor " << i << ": ";
if (factors_[i] != NULL) factors_[i]->print(ss.str(), keyFormatter);
}
}
/* ************************************************************************* */
void NonlinearFactorGraph::saveGraph(std::ostream &stm, const Values& values,
const GraphvizFormatting& graphvizFormatting,
const KeyFormatter& keyFormatter) const
{
stm << "graph {\n";
stm << " size=\"" << graphvizFormatting.figureWidthInches << "," <<
graphvizFormatting.figureHeightInches << "\";\n\n";
FastSet<Key> keys = this->keys();
// Local utility function to extract x and y coordinates
struct { boost::optional<Point2> operator()(
const Value& value, const GraphvizFormatting& graphvizFormatting)
{
if(const Pose2* p = dynamic_cast<const Pose2*>(&value)) {
double x, y;
switch (graphvizFormatting.paperHorizontalAxis) {
case GraphvizFormatting::X: x = p->x(); break;
case GraphvizFormatting::Y: x = p->y(); break;
case GraphvizFormatting::Z: x = 0.0; break;
case GraphvizFormatting::NEGX: x = -p->x(); break;
case GraphvizFormatting::NEGY: x = -p->y(); break;
case GraphvizFormatting::NEGZ: x = 0.0; break;
default: throw std::runtime_error("Invalid enum value");
}
switch (graphvizFormatting.paperVerticalAxis) {
case GraphvizFormatting::X: y = p->x(); break;
case GraphvizFormatting::Y: y = p->y(); break;
case GraphvizFormatting::Z: y = 0.0; break;
case GraphvizFormatting::NEGX: y = -p->x(); break;
case GraphvizFormatting::NEGY: y = -p->y(); break;
case GraphvizFormatting::NEGZ: y = 0.0; break;
default: throw std::runtime_error("Invalid enum value");
}
return Point2(x,y);
} else if(const Pose3* p = dynamic_cast<const Pose3*>(&value)) {
double x, y;
switch (graphvizFormatting.paperHorizontalAxis) {
case GraphvizFormatting::X: x = p->x(); break;
case GraphvizFormatting::Y: x = p->y(); break;
case GraphvizFormatting::Z: x = p->z(); break;
case GraphvizFormatting::NEGX: x = -p->x(); break;
case GraphvizFormatting::NEGY: x = -p->y(); break;
case GraphvizFormatting::NEGZ: x = -p->z(); break;
default: throw std::runtime_error("Invalid enum value");
}
switch (graphvizFormatting.paperVerticalAxis) {
case GraphvizFormatting::X: y = p->x(); break;
case GraphvizFormatting::Y: y = p->y(); break;
case GraphvizFormatting::Z: y = p->z(); break;
case GraphvizFormatting::NEGX: y = -p->x(); break;
case GraphvizFormatting::NEGY: y = -p->y(); break;
case GraphvizFormatting::NEGZ: y = -p->z(); break;
default: throw std::runtime_error("Invalid enum value");
}
return Point2(x,y);
} else {
return boost::none;
}
}} getXY;
// Find bounds
double minX = numeric_limits<double>::infinity(), maxX = -numeric_limits<double>::infinity();
double minY = numeric_limits<double>::infinity(), maxY = -numeric_limits<double>::infinity();
BOOST_FOREACH(Key key, keys) {
if(values.exists(key)) {
boost::optional<Point2> xy = getXY(values.at(key), graphvizFormatting);
if(xy) {
if(xy->x() < minX)
minX = xy->x();
if(xy->x() > maxX)
maxX = xy->x();
if(xy->y() < minY)
minY = xy->y();
if(xy->y() > maxY)
maxY = xy->y();
}
}
}
// Create nodes for each variable in the graph
BOOST_FOREACH(Key key, keys) {
// Label the node with the label from the KeyFormatter
stm << " var" << key << "[label=\"" << keyFormatter(key) << "\"";
if(values.exists(key)) {
boost::optional<Point2> xy = getXY(values.at(key), graphvizFormatting);
if(xy)
stm << ", pos=\"" << graphvizFormatting.scale*(xy->x() - minX) << "," << graphvizFormatting.scale*(xy->y() - minY) << "!\"";
}
stm << "];\n";
}
stm << "\n";
if(graphvizFormatting.mergeSimilarFactors) {
// Remove duplicate factors
FastSet<vector<Key> > structure;
BOOST_FOREACH(const sharedFactor& factor, *this) {
if(factor) {
vector<Key> factorKeys = factor->keys();
std::sort(factorKeys.begin(), factorKeys.end());
structure.insert(factorKeys);
}
}
// Create factors and variable connections
size_t i = 0;
BOOST_FOREACH(const vector<Key>& factorKeys, structure) {
// Make each factor a dot
stm << " factor" << i << "[label=\"\", shape=point";
{
map<size_t, Point2>::const_iterator pos = graphvizFormatting.factorPositions.find(i);
if(pos != graphvizFormatting.factorPositions.end())
stm << ", pos=\"" << graphvizFormatting.scale*(pos->second.x() - minX) << "," << graphvizFormatting.scale*(pos->second.y() - minY) << "!\"";
}
stm << "];\n";
// Make factor-variable connections
BOOST_FOREACH(Key key, factorKeys) {
stm << " var" << key << "--" << "factor" << i << ";\n"; }
++ i;
}
} else {
// Create factors and variable connections
for(size_t i = 0; i < this->size(); ++i) {
// Make each factor a dot
stm << " factor" << i << "[label=\"\", shape=point];\n";
// Make factor-variable connections
if(this->at(i)) {
BOOST_FOREACH(Key key, *this->at(i)) {
stm << " var" << key << "--" << "factor" << i << ";\n"; } }
}
}
stm << "}\n";
}
/* ************************************************************************* */
double NonlinearFactorGraph::error(const Values& c) const {
gttic(NonlinearFactorGraph_error);
double total_error = 0.;
// iterate over all the factors_ to accumulate the log probabilities
BOOST_FOREACH(const sharedFactor& factor, this->factors_) {
if(factor)
total_error += factor->error(c);
}
return total_error;
}
/* ************************************************************************* */
FastSet<Key> NonlinearFactorGraph::keys() const {
FastSet<Key> keys;
BOOST_FOREACH(const sharedFactor& factor, this->factors_) {
if(factor)
keys.insert(factor->begin(), factor->end());
}
return keys;
}
/* ************************************************************************* */
Ordering::shared_ptr NonlinearFactorGraph::orderingCOLAMD(
const Values& config) const
{
gttic(NonlinearFactorGraph_orderingCOLAMD);
// Create symbolic graph and initial (iterator) ordering
SymbolicFactorGraph::shared_ptr symbolic;
Ordering::shared_ptr ordering;
boost::tie(symbolic, ordering) = this->symbolic(config);
// Compute the VariableIndex (column-wise index)
VariableIndex variableIndex(*symbolic, ordering->size());
if (config.size() != variableIndex.size()) throw std::runtime_error(
"orderingCOLAMD: some variables in the graph are not constrained!");
// Compute a fill-reducing ordering with COLAMD
Permutation::shared_ptr colamdPerm(inference::PermutationCOLAMD(
variableIndex));
// Permute the Ordering with the COLAMD ordering
ordering->permuteInPlace(*colamdPerm);
return ordering;
}
/* ************************************************************************* */
Ordering::shared_ptr NonlinearFactorGraph::orderingCOLAMDConstrained(const Values& config,
const std::map<Key, int>& constraints) const
{
gttic(NonlinearFactorGraph_orderingCOLAMDConstrained);
// Create symbolic graph and initial (iterator) ordering
SymbolicFactorGraph::shared_ptr symbolic;
Ordering::shared_ptr ordering;
boost::tie(symbolic, ordering) = this->symbolic(config);
// Compute the VariableIndex (column-wise index)
VariableIndex variableIndex(*symbolic, ordering->size());
if (config.size() != variableIndex.size()) throw std::runtime_error(
"orderingCOLAMD: some variables in the graph are not constrained!");
// Create a constraint list with correct indices
typedef std::map<Key, int>::value_type constraint_type;
std::map<Index, int> index_constraints;
BOOST_FOREACH(const constraint_type& p, constraints)
index_constraints[ordering->at(p.first)] = p.second;
// Compute a constrained fill-reducing ordering with COLAMD
Permutation::shared_ptr colamdPerm(inference::PermutationCOLAMDGrouped(
variableIndex, index_constraints));
// Permute the Ordering with the COLAMD ordering
ordering->permuteInPlace(*colamdPerm);
return ordering;
}
/* ************************************************************************* */
SymbolicFactorGraph::shared_ptr NonlinearFactorGraph::symbolic(const Ordering& ordering) const {
gttic(NonlinearFactorGraph_symbolic_from_Ordering);
// Generate the symbolic factor graph
SymbolicFactorGraph::shared_ptr symbolicfg(new SymbolicFactorGraph);
symbolicfg->reserve(this->size());
BOOST_FOREACH(const sharedFactor& factor, this->factors_) {
if(factor)
symbolicfg->push_back(factor->symbolic(ordering));
else
symbolicfg->push_back(SymbolicFactorGraph::sharedFactor());
}
return symbolicfg;
}
/* ************************************************************************* */
pair<SymbolicFactorGraph::shared_ptr, Ordering::shared_ptr> NonlinearFactorGraph::symbolic(
const Values& config) const
{
gttic(NonlinearFactorGraph_symbolic_from_Values);
// Generate an initial key ordering in iterator order
Ordering::shared_ptr ordering(config.orderingArbitrary());
return make_pair(symbolic(*ordering), ordering);
}
/* ************************************************************************* */
GaussianFactorGraph::shared_ptr NonlinearFactorGraph::linearize(
const Values& config, const Ordering& ordering) const
{
gttic(NonlinearFactorGraph_linearize);
// create an empty linear FG
GaussianFactorGraph::shared_ptr linearFG(new GaussianFactorGraph);
linearFG->reserve(this->size());
// linearize all factors
BOOST_FOREACH(const sharedFactor& factor, this->factors_) {
if(factor) {
GaussianFactor::shared_ptr lf = factor->linearize(config, ordering);
if (lf) linearFG->push_back(lf);
} else
linearFG->push_back(GaussianFactor::shared_ptr());
}
return linearFG;
}
/* ************************************************************************* */
NonlinearFactorGraph NonlinearFactorGraph::clone() const {
NonlinearFactorGraph result;
BOOST_FOREACH(const sharedFactor& f, *this) {
if (f)
result.push_back(f->clone());
else
result.push_back(sharedFactor()); // Passes on null factors so indices remain valid
}
return result;
}
/* ************************************************************************* */
NonlinearFactorGraph NonlinearFactorGraph::rekey(const std::map<Key,Key>& rekey_mapping) const {
NonlinearFactorGraph result;
BOOST_FOREACH(const sharedFactor& f, *this) {
if (f)
result.push_back(f->rekey(rekey_mapping));
else
result.push_back(sharedFactor());
}
return result;
}
/* ************************************************************************* */
} // namespace gtsam