500 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			C++
		
	
	
			
		
		
	
	
			500 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			C++
		
	
	
| /* ----------------------------------------------------------------------------
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| 
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|  * GTSAM Copyright 2010, Georgia Tech Research Corporation, 
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|  * Atlanta, Georgia 30332-0415
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|  * All Rights Reserved
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|  * Authors: Frank Dellaert, et al. (see THANKS for the full author list)
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| 
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|  * See LICENSE for the license information
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| 
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|  * -------------------------------------------------------------------------- */
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| 
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| /**
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|  * @file    smallExample.cpp
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|  * @brief   Create small example with two poses and one landmark
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|  * @brief   smallExample
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|  * @author  Carlos Nieto
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|  * @author  Frank dellaert
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|  */
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| 
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| #include <gtsam/nonlinear/Symbol.h>
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| #include <gtsam/nonlinear/Ordering.h>
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| #include <gtsam/nonlinear/NonlinearFactorGraph.h>
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| #include <gtsam/nonlinear/NonlinearFactor.h>
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| #include <gtsam/inference/FactorGraph.h>
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| #include <gtsam/base/Matrix.h>
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| 
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| #include <tests/smallExample.h>
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| 
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| #include <boost/optional.hpp>
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| #include <boost/shared_ptr.hpp>
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| 
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| #include <iostream>
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| #include <string>
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| 
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| using namespace std;
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| 
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| namespace gtsam {
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| namespace example {
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| 
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| 	typedef boost::shared_ptr<NonlinearFactor> shared;
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| 
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| 	static SharedDiagonal sigma1_0 = noiseModel::Isotropic::Sigma(2,1.0);
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| 	static SharedDiagonal sigma0_1 = noiseModel::Isotropic::Sigma(2,0.1);
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| 	static SharedDiagonal sigma0_2 = noiseModel::Isotropic::Sigma(2,0.2);
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| 	static SharedDiagonal constraintModel = noiseModel::Constrained::All(2);
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| 
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| 	static const Index _l1_=0, _x1_=1, _x2_=2;
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| 	static const Index _x_=0, _y_=1, _z_=2;
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| 
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| 	// Convenience for named keys
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| 	using symbol_shorthand::X;
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| 	using symbol_shorthand::L;
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| 
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| 	/* ************************************************************************* */
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| 	boost::shared_ptr<const Graph> sharedNonlinearFactorGraph() {
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| 		// Create
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| 		boost::shared_ptr<Graph> nlfg(
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| 				new Graph);
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| 
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| 		// prior on x1
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| 		Point2 mu;
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| 		shared f1(new simulated2D::Prior(mu, sigma0_1, X(1)));
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| 		nlfg->push_back(f1);
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| 
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| 		// odometry between x1 and x2
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| 		Point2 z2(1.5, 0);
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| 		shared f2(new simulated2D::Odometry(z2, sigma0_1, X(1), X(2)));
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| 		nlfg->push_back(f2);
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| 
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| 		// measurement between x1 and l1
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| 		Point2 z3(0, -1);
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| 		shared f3(new simulated2D::Measurement(z3, sigma0_2, X(1), L(1)));
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| 		nlfg->push_back(f3);
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| 
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| 		// measurement between x2 and l1
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| 		Point2 z4(-1.5, -1.);
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| 		shared f4(new simulated2D::Measurement(z4, sigma0_2, X(2), L(1)));
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| 		nlfg->push_back(f4);
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| 
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| 		return nlfg;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	Graph createNonlinearFactorGraph() {
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| 		return *sharedNonlinearFactorGraph();
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	Values createValues() {
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| 		Values c;
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| 		c.insert(X(1), Point2(0.0, 0.0));
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| 		c.insert(X(2), Point2(1.5, 0.0));
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| 		c.insert(L(1), Point2(0.0, -1.0));
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| 		return c;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	VectorValues createVectorValues() {
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| 		VectorValues c(vector<size_t>(3, 2));
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| 		c[_l1_] = Vector_(2, 0.0, -1.0);
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| 		c[_x1_] = Vector_(2, 0.0, 0.0);
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| 		c[_x2_] = Vector_(2, 1.5, 0.0);
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| 		return c;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	boost::shared_ptr<const Values> sharedNoisyValues() {
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| 		boost::shared_ptr<Values> c(new Values);
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| 		c->insert(X(1), Point2(0.1, 0.1));
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| 		c->insert(X(2), Point2(1.4, 0.2));
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| 		c->insert(L(1), Point2(0.1, -1.1));
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| 		return c;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	Values createNoisyValues() {
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| 		return *sharedNoisyValues();
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	VectorValues createCorrectDelta(const Ordering& ordering) {
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| 		VectorValues c(vector<size_t>(3,2));
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| 		c[ordering[L(1)]] = Vector_(2, -0.1, 0.1);
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| 		c[ordering[X(1)]] = Vector_(2, -0.1, -0.1);
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| 		c[ordering[X(2)]] = Vector_(2, 0.1, -0.2);
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| 		return c;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	VectorValues createZeroDelta(const Ordering& ordering) {
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| 		VectorValues c(vector<size_t>(3,2));
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| 		c[ordering[L(1)]] = zero(2);
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| 		c[ordering[X(1)]] = zero(2);
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| 		c[ordering[X(2)]] = zero(2);
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| 		return c;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	JacobianFactorGraph createGaussianFactorGraph(const Ordering& ordering) {
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| 		// Create empty graph
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| 		JacobianFactorGraph fg;
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| 
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| 		SharedDiagonal unit2 = noiseModel::Unit::Create(2);
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| 
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| 		// linearized prior on x1: c[_x1_]+x1=0 i.e. x1=-c[_x1_]
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| 		fg.push_back(boost::make_shared<JacobianFactor>(ordering[X(1)], 10*eye(2), -1.0*ones(2), unit2));
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| 
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| 		// odometry between x1 and x2: x2-x1=[0.2;-0.1]
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| 		fg.push_back(boost::make_shared<JacobianFactor>(ordering[X(1)], -10*eye(2),ordering[X(2)], 10*eye(2), Vector_(2, 2.0, -1.0), unit2));
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| 
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|     // measurement between x1 and l1: l1-x1=[0.0;0.2]
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| 		fg.push_back(boost::make_shared<JacobianFactor>(ordering[X(1)], -5*eye(2), ordering[L(1)], 5*eye(2), Vector_(2, 0.0, 1.0), unit2));
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| 
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| 		// measurement between x2 and l1: l1-x2=[-0.2;0.3]
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| 		fg.push_back(boost::make_shared<JacobianFactor>(ordering[X(2)], -5*eye(2), ordering[L(1)], 5*eye(2), Vector_(2, -1.0, 1.5), unit2));
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| 
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| 		return fg;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	/** create small Chordal Bayes Net x <- y
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| 	 * x y d
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| 	 * 1 1 9
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| 	 *   1 5
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| 	 */
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| 	GaussianBayesNet createSmallGaussianBayesNet() {
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| 		Matrix R11 = Matrix_(1, 1, 1.0), S12 = Matrix_(1, 1, 1.0);
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| 		Matrix R22 = Matrix_(1, 1, 1.0);
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| 		Vector d1(1), d2(1);
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| 		d1(0) = 9;
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| 		d2(0) = 5;
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| 		Vector tau(1);
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| 		tau(0) = 1.0;
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| 
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| 		// define nodes and specify in reverse topological sort (i.e. parents last)
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| 		GaussianConditional::shared_ptr Px_y(new GaussianConditional(_x_, d1, R11, _y_, S12, tau));
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| 		GaussianConditional::shared_ptr Py(new GaussianConditional(_y_, d2, R22, tau));
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| 		GaussianBayesNet cbn;
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| 		cbn.push_back(Px_y);
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| 		cbn.push_back(Py);
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| 
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| 		return cbn;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	// Some nonlinear functions to optimize
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| 	/* ************************************************************************* */
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| 	namespace smallOptimize {
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| 
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| 		Point2 h(const Point2& v) {
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| 			return Point2(cos(v.x()), sin(v.y()));
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| 		}
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| 
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| 		Matrix H(const Point2& v) {
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| 			return Matrix_(2, 2,
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| 					-sin(v.x()), 0.0,
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| 					 0.0, cos(v.y()));
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| 		}
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| 
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| 		struct UnaryFactor: public gtsam::NoiseModelFactor1<Point2> {
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| 
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| 			Point2 z_;
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| 
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| 			UnaryFactor(const Point2& z, const SharedNoiseModel& model, Key key) :
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| 				gtsam::NoiseModelFactor1<Point2>(model, key), z_(z) {
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| 			}
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| 
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| 			Vector evaluateError(const Point2& x, boost::optional<Matrix&> A = boost::none) const {
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| 				if (A) *A = H(x);
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| 				return (h(x) - z_).vector();
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| 			}
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| 
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| 		};
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| 
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	boost::shared_ptr<const Graph> sharedReallyNonlinearFactorGraph() {
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| 		boost::shared_ptr<Graph> fg(new Graph);
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| 		Vector z = Vector_(2, 1.0, 0.0);
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| 		double sigma = 0.1;
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| 		boost::shared_ptr<smallOptimize::UnaryFactor> factor(
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| 				new smallOptimize::UnaryFactor(z, noiseModel::Isotropic::Sigma(2,sigma), X(1)));
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| 		fg->push_back(factor);
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| 		return fg;
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| 	}
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| 
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| 	Graph createReallyNonlinearFactorGraph() {
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| 		return *sharedReallyNonlinearFactorGraph();
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	pair<Graph, Values> createNonlinearSmoother(int T) {
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| 
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| 		// Create
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| 		Graph nlfg;
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| 		Values poses;
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| 
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| 		// prior on x1
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| 		Point2 x1(1.0, 0.0);
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| 		shared prior(new simulated2D::Prior(x1, sigma1_0, X(1)));
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| 		nlfg.push_back(prior);
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| 		poses.insert(X(1), x1);
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| 
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| 		for (int t = 2; t <= T; t++) {
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| 			// odometry between x_t and x_{t-1}
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| 			Point2 odo(1.0, 0.0);
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| 			shared odometry(new simulated2D::Odometry(odo, sigma1_0, X(t - 1), X(t)));
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| 			nlfg.push_back(odometry);
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| 
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| 			// measurement on x_t is like perfect GPS
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| 			Point2 xt(t, 0);
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| 			shared measurement(new simulated2D::Prior(xt, sigma1_0, X(t)));
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| 			nlfg.push_back(measurement);
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| 
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| 			// initial estimate
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| 			poses.insert(X(t), xt);
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| 		}
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| 
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| 		return make_pair(nlfg, poses);
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	pair<FactorGraph<GaussianFactor>, Ordering> createSmoother(int T, boost::optional<Ordering> ordering) {
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| 		Graph nlfg;
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| 		Values poses;
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| 		boost::tie(nlfg, poses) = createNonlinearSmoother(T);
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| 
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| 		if(!ordering) ordering = *poses.orderingArbitrary();
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| 		return make_pair(*nlfg.linearize(poses, *ordering), *ordering);
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	JacobianFactorGraph createSimpleConstraintGraph() {
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| 		// create unary factor
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| 		// prior on _x_, mean = [1,-1], sigma=0.1
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| 		Matrix Ax = eye(2);
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| 		Vector b1(2);
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| 		b1(0) = 1.0;
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| 		b1(1) = -1.0;
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| 		JacobianFactor::shared_ptr f1(new JacobianFactor(_x_, Ax, b1, sigma0_1));
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| 
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| 		// create binary constraint factor
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| 		// between _x_ and _y_, that is going to be the only factor on _y_
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| 		// |1 0||x_1| + |-1  0||y_1| = |0|
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| 		// |0 1||x_2|   | 0 -1||y_2|   |0|
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| 		Matrix Ax1 = eye(2);
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| 		Matrix Ay1 = eye(2) * -1;
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| 		Vector b2 = Vector_(2, 0.0, 0.0);
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| 		JacobianFactor::shared_ptr f2(new JacobianFactor(_x_, Ax1, _y_, Ay1, b2,
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| 				constraintModel));
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| 
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| 		// construct the graph
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| 		JacobianFactorGraph fg;
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| 		fg.push_back(f1);
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| 		fg.push_back(f2);
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| 
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| 		return fg;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	VectorValues createSimpleConstraintValues() {
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| 		VectorValues config(vector<size_t>(2,2));
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| 		Vector v = Vector_(2, 1.0, -1.0);
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| 		config[_x_] = v;
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| 		config[_y_] = v;
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| 		return config;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	JacobianFactorGraph createSingleConstraintGraph() {
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| 		// create unary factor
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| 		// prior on _x_, mean = [1,-1], sigma=0.1
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| 		Matrix Ax = eye(2);
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| 		Vector b1(2);
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| 		b1(0) = 1.0;
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| 		b1(1) = -1.0;
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| 		//GaussianFactor::shared_ptr f1(new JacobianFactor(_x_, sigma0_1->Whiten(Ax), sigma0_1->whiten(b1), sigma0_1));
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| 		JacobianFactor::shared_ptr f1(new JacobianFactor(_x_, Ax, b1, sigma0_1));
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| 
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| 		// create binary constraint factor
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| 		// between _x_ and _y_, that is going to be the only factor on _y_
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| 		// |1 2||x_1| + |10 0||y_1| = |1|
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| 		// |2 1||x_2|   |0 10||y_2|   |2|
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| 		Matrix Ax1(2, 2);
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| 		Ax1(0, 0) = 1.0;
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| 		Ax1(0, 1) = 2.0;
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| 		Ax1(1, 0) = 2.0;
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| 		Ax1(1, 1) = 1.0;
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| 		Matrix Ay1 = eye(2) * 10;
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| 		Vector b2 = Vector_(2, 1.0, 2.0);
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| 		JacobianFactor::shared_ptr f2(new JacobianFactor(_x_, Ax1, _y_, Ay1, b2,
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| 				constraintModel));
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| 
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| 		// construct the graph
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| 		JacobianFactorGraph fg;
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| 		fg.push_back(f1);
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| 		fg.push_back(f2);
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| 
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| 		return fg;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	VectorValues createSingleConstraintValues() {
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| 		VectorValues config(vector<size_t>(2,2));
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| 		config[_x_] = Vector_(2, 1.0, -1.0);
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| 		config[_y_] = Vector_(2, 0.2, 0.1);
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| 		return config;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	JacobianFactorGraph createMultiConstraintGraph() {
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| 		// unary factor 1
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| 		Matrix A = eye(2);
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| 		Vector b = Vector_(2, -2.0, 2.0);
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| 		JacobianFactor::shared_ptr lf1(new JacobianFactor(_x_, A, b, sigma0_1));
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| 
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| 		// constraint 1
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| 		Matrix A11(2, 2);
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| 		A11(0, 0) = 1.0;
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| 		A11(0, 1) = 2.0;
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| 		A11(1, 0) = 2.0;
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| 		A11(1, 1) = 1.0;
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| 
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| 		Matrix A12(2, 2);
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| 		A12(0, 0) = 10.0;
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| 		A12(0, 1) = 0.0;
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| 		A12(1, 0) = 0.0;
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| 		A12(1, 1) = 10.0;
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| 
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| 		Vector b1(2);
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| 		b1(0) = 1.0;
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| 		b1(1) = 2.0;
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| 		JacobianFactor::shared_ptr lc1(new JacobianFactor(_x_, A11, _y_, A12, b1,
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| 				constraintModel));
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| 
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| 		// constraint 2
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| 		Matrix A21(2, 2);
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| 		A21(0, 0) = 3.0;
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| 		A21(0, 1) = 4.0;
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| 		A21(1, 0) = -1.0;
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| 		A21(1, 1) = -2.0;
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| 
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| 		Matrix A22(2, 2);
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| 		A22(0, 0) = 1.0;
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| 		A22(0, 1) = 1.0;
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| 		A22(1, 0) = 1.0;
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| 		A22(1, 1) = 2.0;
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| 
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| 		Vector b2(2);
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| 		b2(0) = 3.0;
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| 		b2(1) = 4.0;
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| 		JacobianFactor::shared_ptr lc2(new JacobianFactor(_x_, A21, _z_, A22, b2,
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| 				constraintModel));
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| 
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| 		// construct the graph
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| 		JacobianFactorGraph fg;
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| 		fg.push_back(lf1);
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| 		fg.push_back(lc1);
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| 		fg.push_back(lc2);
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| 
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| 		return fg;
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	VectorValues createMultiConstraintValues() {
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| 		VectorValues config(vector<size_t>(3,2));
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| 		config[_x_] = Vector_(2, -2.0, 2.0);
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| 		config[_y_] = Vector_(2, -0.1, 0.4);
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| 		config[_z_] = Vector_(2, -4.0, 5.0);
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| 		return config;
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| 	}
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| 
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| 
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| 	/* ************************************************************************* */
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| 	// Create key for simulated planar graph
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| 	Symbol key(int x, int y) {
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| 		return X(1000*x+y);
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| 	}
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| 
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| 	/* ************************************************************************* */
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| 	boost::tuple<GaussianFactorGraph, VectorValues> planarGraph(size_t N) {
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| 
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| 		// create empty graph
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| 		NonlinearFactorGraph nlfg;
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| 
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| 		// Create almost hard constraint on x11, sigma=0 will work for PCG not for normal
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| 		shared constraint(new simulated2D::Prior(Point2(1.0, 1.0), sharedSigma(2,1e-3), key(1,1)));
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| 		nlfg.push_back(constraint);
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| 
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| 		// Create horizontal constraints, 1...N*(N-1)
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| 		Point2 z1(1.0, 0.0); // move right
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| 		for (size_t x = 1; x < N; x++)
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| 			for (size_t y = 1; y <= N; y++) {
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| 				shared f(new simulated2D::Odometry(z1, sharedSigma(2,0.01), key(x, y), key(x + 1, y)));
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| 				nlfg.push_back(f);
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| 			}
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| 
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| 		// Create vertical constraints, N*(N-1)+1..2*N*(N-1)
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| 		Point2 z2(0.0, 1.0); // move up
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| 		for (size_t x = 1; x <= N; x++)
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| 			for (size_t y = 1; y < N; y++) {
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| 				shared f(new simulated2D::Odometry(z2, sharedSigma(2,0.01), key(x, y), key(x, y + 1)));
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| 				nlfg.push_back(f);
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| 			}
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| 
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| 		// Create linearization and ground xtrue config
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| 		Values zeros;
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|     for (size_t x = 1; x <= N; x++)
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|       for (size_t y = 1; y <= N; y++)
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|         zeros.insert(key(x, y), Point2());
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| 		Ordering ordering(planarOrdering(N));
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| 		VectorValues xtrue(zeros.dims(ordering));
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| 		for (size_t x = 1; x <= N; x++)
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| 			for (size_t y = 1; y <= N; y++)
 | |
| 				xtrue[ordering[key(x, y)]] = Point2(x,y).vector();
 | |
| 
 | |
| 		// linearize around zero
 | |
| 		return boost::make_tuple(*nlfg.linearize(zeros, ordering), xtrue);
 | |
| 	}
 | |
| 
 | |
| 	/* ************************************************************************* */
 | |
| 	Ordering planarOrdering(size_t N) {
 | |
| 		Ordering ordering;
 | |
| 		for (size_t y = N; y >= 1; y--)
 | |
| 			for (size_t x = N; x >= 1; x--)
 | |
| 				ordering.push_back(key(x, y));
 | |
| 		return ordering;
 | |
| 	}
 | |
| 
 | |
| 	/* ************************************************************************* */
 | |
| 	pair<JacobianFactorGraph, JacobianFactorGraph > splitOffPlanarTree(size_t N,
 | |
| 			const JacobianFactorGraph& original) {
 | |
| 		JacobianFactorGraph T, C;
 | |
| 
 | |
| 		// Add the x11 constraint to the tree
 | |
| 		T.push_back(original[0]);
 | |
| 
 | |
| 		// Add all horizontal constraints to the tree
 | |
| 		size_t i = 1;
 | |
| 		for (size_t x = 1; x < N; x++)
 | |
| 			for (size_t y = 1; y <= N; y++, i++)
 | |
| 				T.push_back(original[i]);
 | |
| 
 | |
| 		// Add first vertical column of constraints to T, others to C
 | |
| 		for (size_t x = 1; x <= N; x++)
 | |
| 			for (size_t y = 1; y < N; y++, i++)
 | |
| 				if (x == 1)
 | |
| 					T.push_back(original[i]);
 | |
| 				else
 | |
| 					C.push_back(original[i]);
 | |
| 
 | |
| 		return make_pair(T, C);
 | |
| 	}
 | |
| 
 | |
| /* ************************************************************************* */
 | |
| 
 | |
| } // example
 | |
| } // namespace gtsam
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