gtsam/slam/smallExample.h

/**
 * @file    smallExample.h
 * @brief   Create small example with two poses and one landmark
 * @brief   smallExample
 * @author  Carlos Nieto
 */

// \callgraph


#pragma once

#include <boost/shared_ptr.hpp>
#include "NonlinearFactorGraph.h"
#include "simulated2D.h"

namespace gtsam {
	namespace example {

		typedef simulated2D::Config Config;
		typedef NonlinearFactorGraph<Config> Graph;

		/**
		 * Create small example for non-linear factor graph
		 */
		boost::shared_ptr<const Graph> sharedNonlinearFactorGraph();
		Graph createNonlinearFactorGraph();

		/**
		 * Create configuration to go with it
		 * The ground truth configuration for the example above
		 */
		Config createConfig();

		/** Vector Config equivalent */
		VectorConfig createVectorConfig();

		/**
		 * create a noisy configuration for a nonlinear factor graph
		 */
		boost::shared_ptr<const Config> sharedNoisyConfig();
		Config createNoisyConfig();

		/**
		 * Zero delta config
		 */
		VectorConfig createZeroDelta();

		/**
		 * Delta config that, when added to noisyConfig, returns the ground truth
		 */
		VectorConfig createCorrectDelta();

		/**
		 * create a linear factor graph
		 * The non-linear graph above evaluated at NoisyConfig
		 */
		GaussianFactorGraph createGaussianFactorGraph();

		/**
		 * create small Chordal Bayes Net x <- y
		 */
		GaussianBayesNet createSmallGaussianBayesNet();

		/**
		 * Create really non-linear factor graph (cos/sin)
		 */
		boost::shared_ptr<const Graph>
		sharedReallyNonlinearFactorGraph();
		Graph createReallyNonlinearFactorGraph();

		/**
		 * Create a full nonlinear smoother
		 * @param T number of time-steps
		 */
		std::pair<Graph, Config> createNonlinearSmoother(int T);

		/**
		 * Create a Kalman smoother by linearizing a non-linear factor graph
		 * @param T number of time-steps
		 */
		GaussianFactorGraph createSmoother(int T);

		/* ******************************************************* */
		// Constrained Examples
		/* ******************************************************* */

		/**
		 * Creates a simple constrained graph with one linear factor and
		 * one binary equality constraint that sets x = y
		 */
		GaussianFactorGraph createSimpleConstraintGraph();
		VectorConfig createSimpleConstraintConfig();

		/**
		 * Creates a simple constrained graph with one linear factor and
		 * one binary constraint.
		 */
		GaussianFactorGraph createSingleConstraintGraph();
		VectorConfig createSingleConstraintConfig();

		/**
		 * Creates a constrained graph with a linear factor and two
		 * binary constraints that share a node
		 */
		GaussianFactorGraph createMultiConstraintGraph();
		VectorConfig createMultiConstraintConfig();

		/**
		 * These are the old examples from the EqualityFactor/DeltaFunction
		 * They should be updated for use at some point, but are disabled for now
		 */
		/**
		 * Create configuration for constrained example
		 * This is the ground truth version
		 */
		//VectorConfig createConstrainedConfig();

		/**
		 * Create a noisy configuration for linearization
		 */
		//VectorConfig createConstrainedLinConfig();

		/**
		 * Create the correct delta configuration
		 */
		//VectorConfig createConstrainedCorrectDelta();

		/**
		 * Create small example constrained factor graph
		 */
		//GaussianFactorGraph createConstrainedGaussianFactorGraph();

		/**
		 * Create small example constrained nonlinear factor graph
		 */
		//	ConstrainedNonlinearFactorGraph<NonlinearFactor<VectorConfig>,VectorConfig>
		//		createConstrainedNonlinearFactorGraph();

		/* ******************************************************* */
		// Planar graph with easy subtree for SubgraphPreconditioner
		/* ******************************************************* */

		/*
		 * Create factor graph with N^2 nodes, for example for N=3
		 *  x13-x23-x33
		 *   |   |   |
		 *  x12-x22-x32
		 *   |   |   |
		 * -x11-x21-x31
		 * with x11 clamped at (1,1), and others related by 2D odometry.
		 */
		std::pair<GaussianFactorGraph, VectorConfig> planarGraph(size_t N);

		/*
		 * Create canonical ordering for planar graph that also works for tree
		 * With x11 the root, e.g. for N=3
		 * x33 x23 x13 x32 x22 x12 x31 x21 x11
		 */
		Ordering planarOrdering(size_t N);

		/*
		 * Split graph into tree and loop closing constraints, e.g., with N=3
		 *  x13-x23-x33
		 *   |
		 *  x12-x22-x32
		 *   |
		 * -x11-x21-x31
		 */
		std::pair<GaussianFactorGraph, GaussianFactorGraph> splitOffPlanarTree(
				size_t N, const GaussianFactorGraph& original);

	} // example
} // gtsam