add BlockJacobiPreconditioner class and unit test

release/4.3a0
Yong-Dian Jian 2014-06-08 16:15:00 -04:00
parent e8d3809917
commit 67398f0f13
3 changed files with 233 additions and 52 deletions

View File

@ -9,6 +9,7 @@
//#include <gtsam/linear/CombinatorialPreconditioner.h>
#include <gtsam/inference/FactorGraph-inst.h>
//#include <gtsam/linear/FactorGraphUtil-inl.h>
#include <gtsam/linear/GaussianFactorGraph.h>
#include <gtsam/linear/PCGSolver.h>
#include <gtsam/linear/Preconditioner.h>
//#include <gtsam/linear/JacobianFactorGraph.h>
@ -83,26 +84,137 @@ std::string PreconditionerParameters::verbosityTranslator(PreconditionerParamete
else return "UNKNOWN";
}
///***************************************************************************************/
//void Preconditioner::replaceFactors(const JacobianFactorGraph &jfg, const double lambda)
//{
// const Parameters &p = *parameters_;
//
// if ( keyInfo_.size() == 0 ) {
// keyInfo_ = KeyInfo(jfg, *orderingNatural(jfg));
// }
//
// if ( p.verbosity() >= Parameters::COMPLEXITY )
// cout << "Preconditioner::replaceFactors with a jfg of " << jfg.size() << " factors."<< endl;
//}
//
/***************************************************************************************/
BlockJacobiPreconditioner::BlockJacobiPreconditioner()
: Base(), buffer_(0), bufferSize_(0), nnz_(0) {}
/***************************************************************************************/
BlockJacobiPreconditioner::~BlockJacobiPreconditioner() { clean(); }
/***************************************************************************************/
void BlockJacobiPreconditioner::solve(const Vector& y, Vector &x) const {
const size_t n = dims_.size();
double *ptr = buffer_, *dst = x.data();
std::copy(y.data(), y.data() + y.rows(), x.data());
for ( size_t i = 0 ; i < n ; ++i ) {
const size_t d = dims_[i];
const size_t sz = d*d;
const Eigen::Map<const Eigen::MatrixXd> R(ptr, d, d);
Eigen::Map<Eigen::VectorXd> b(dst, d, 1);
R.triangularView<Eigen::Upper>().solveInPlace(b);
dst += d;
ptr += sz;
}
}
/***************************************************************************************/
void BlockJacobiPreconditioner::transposeSolve(const Vector& y, Vector& x) const {
const size_t n = dims_.size();
double *ptr = buffer_, *dst = x.data();
std::copy(y.data(), y.data() + y.rows(), x.data());
for ( size_t i = 0 ; i < n ; ++i ) {
const size_t d = dims_[i];
const size_t sz = d*d;
const Eigen::Map<const Eigen::MatrixXd> R(ptr, d, d);
Eigen::Map<Eigen::VectorXd> b(dst, d, 1);
R.transpose().triangularView<Eigen::Upper>().solveInPlace(b);
dst += d;
ptr += sz;
}
}
/***************************************************************************************/
void BlockJacobiPreconditioner::build(
const GaussianFactorGraph &gfg, const KeyInfo &keyInfo, const std::map<Key,Vector> &lambda)
{
const size_t n = keyInfo.size();
dims_ = keyInfo.colSpec();
/* prepare the buffer of block diagonals */
std::vector<Matrix> blocks; blocks.reserve(n);
/* allocate memory for the factorization of block diagonals */
size_t nnz = 0;
for ( size_t i = 0 ; i < n ; ++i ) {
const size_t dim = dims_[i];
blocks.push_back(Matrix::Zero(dim, dim));
// nnz += (((dim)*(dim+1)) >> 1); // d*(d+1) / 2 ;
nnz += dim*dim;
}
/* compute the block diagonal by scanning over the factors */
BOOST_FOREACH ( const GaussianFactor::shared_ptr &gf, gfg ) {
if ( JacobianFactor::shared_ptr jf = boost::dynamic_pointer_cast<JacobianFactor>(gf) ) {
for ( JacobianFactor::const_iterator it = jf->begin() ; it != jf->end() ; ++it ) {
const KeyInfoEntry &entry = keyInfo.find(*it)->second;
const Matrix &Ai = jf->getA(it);
blocks[entry.index()] += (Ai.transpose() * Ai);
}
}
else if ( HessianFactor::shared_ptr hf = boost::dynamic_pointer_cast<HessianFactor>(gf) ) {
for ( HessianFactor::const_iterator it = hf->begin() ; it != hf->end() ; ++it ) {
const KeyInfoEntry &entry = keyInfo.find(*it)->second;
const Matrix &Hii = hf->info(it, it).selfadjointView();
blocks[entry.index()] += Hii;
}
}
else {
throw invalid_argument("BlockJacobiPreconditioner::build gfg contains a factor that is neither a JacobianFactor nor a HessianFactor.");
}
}
/* if necessary, allocating the memory for cacheing the factorization results */
if ( nnz > bufferSize_ ) {
clean();
buffer_ = new double [nnz];
bufferSize_ = nnz;
}
nnz_ = nnz;
/* factorizing the blocks respectively */
double *ptr = buffer_;
for ( size_t i = 0 ; i < n ; ++i ) {
/* use eigen to decompose Di */
const Matrix R = blocks[i].llt().matrixL().transpose();
/* store the data in the buffer */
size_t sz = dims_[i]*dims_[i] ;
std::copy(R.data(), R.data() + sz, ptr);
/* advance the pointer */
ptr += sz;
}
}
/*****************************************************************************/
void BlockJacobiPreconditioner::clean() {
if ( buffer_ ) {
delete [] buffer_;
buffer_ = 0;
bufferSize_ = 0;
nnz_ = 0;
}
}
/***************************************************************************************/
boost::shared_ptr<Preconditioner> createPreconditioner(const boost::shared_ptr<PreconditionerParameters> parameters) {
DummyPreconditionerParameters::shared_ptr dummy = boost::dynamic_pointer_cast<DummyPreconditionerParameters>(parameters);
if ( dummy ) {
if ( DummyPreconditionerParameters::shared_ptr dummy = boost::dynamic_pointer_cast<DummyPreconditionerParameters>(parameters) ) {
return boost::make_shared<DummyPreconditioner>();
}
else if ( BlockJacobiPreconditionerParameters::shared_ptr blockJacobi = boost::dynamic_pointer_cast<BlockJacobiPreconditionerParameters>(parameters) ) {
return boost::make_shared<BlockJacobiPreconditioner>();
}
// BlockJacobiPreconditioner::Parameters::shared_ptr jacobi = boost::dynamic_pointer_cast<BlockJacobiPreconditioner::Parameters>(parameters);
// if ( jacobi ) {

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@ -18,7 +18,6 @@ namespace gtsam {
class GaussianFactorGraph;
class KeyInfo;
class VectorValues;
//class Subgraph;
/* parameters for the preconditioner */
struct PreconditionerParameters {
@ -75,15 +74,15 @@ public:
/* implement x = S^{-1} y */
virtual void solve(const Vector& y, Vector &x) const = 0;
virtual void solve(const VectorValues& y, VectorValues &x) const = 0;
// virtual void solve(const VectorValues& y, VectorValues &x) const = 0;
/* implement x = S^{-T} y */
virtual void transposeSolve(const Vector& y, Vector& x) const = 0;
virtual void transposeSolve(const VectorValues& y, VectorValues &x) const = 0;
// virtual void transposeSolve(const VectorValues& y, VectorValues &x) const = 0;
/* implement x = S^{-1} S^{-T} y */
virtual void fullSolve(const Vector& y, Vector &x) const = 0;
virtual void fullSolve(const VectorValues& y, VectorValues &x) const = 0;
// /* implement x = S^{-1} S^{-T} y */
// virtual void fullSolve(const Vector& y, Vector &x) const = 0;
// virtual void fullSolve(const VectorValues& y, VectorValues &x) const = 0;
/* build/factorize the preconditioner */
virtual void build(
@ -91,23 +90,6 @@ public:
const KeyInfo &info,
const std::map<Key,Vector> &lambda
) = 0;
// /* complexity index */
// virtual size_t complexity() const = 0;
//
// /* is the preconditioner dependent to data */
// virtual bool isStatic() const = 0;
//
// /* is the preconditioner kind of spanning subgraph preconditioner */
// virtual bool isSubgraph() const = 0;
//
// /* return A\b */
// virtual void xstar(Vector &result) const = 0 ;
//
//protected:
// Parameters::shared_ptr parameters_;
// KeyInfo keyInfo_;
};
/*******************************************************************************************/
@ -131,30 +113,57 @@ public:
/* Computation Interfaces for raw vector */
virtual void solve(const Vector& y, Vector &x) const { x = y; }
virtual void solve(const VectorValues& y, VectorValues& x) const { x = y; }
// virtual void solve(const VectorValues& y, VectorValues& x) const { x = y; }
virtual void transposeSolve(const Vector& y, Vector& x) const { x = y; }
virtual void transposeSolve(const VectorValues& y, VectorValues& x) const { x = y; }
// virtual void transposeSolve(const VectorValues& y, VectorValues& x) const { x = y; }
virtual void fullSolve(const Vector& y, Vector &x) const { x = y; }
virtual void fullSolve(const VectorValues& y, VectorValues& x) const { x = y; }
// virtual void fullSolve(const Vector& y, Vector &x) const { x = y; }
// virtual void fullSolve(const VectorValues& y, VectorValues& x) const { x = y; }
virtual void build(
const GaussianFactorGraph &gfg,
const KeyInfo &info,
const std::map<Key,Vector> &lambda
) {}
// virtual void replaceFactors(const JacobianFactorGraph &jfg, const double lambda = 0.0) {
// Base::replaceFactors(jfg,lambda);
// }
// virtual void buildPreconditioner() {}
// virtual size_t complexity() const { return 0; }
// virtual bool isStatic() const { return true; }
// virtual bool isSubgraph() const { return false; }
// virtual void xstar(Vector &result) const {}
};
/*******************************************************************************************/
struct BlockJacobiPreconditionerParameters : public PreconditionerParameters {
typedef PreconditionerParameters Base;
BlockJacobiPreconditionerParameters() : Base() {}
virtual ~BlockJacobiPreconditionerParameters() {}
};
/*******************************************************************************************/
class BlockJacobiPreconditioner : public Preconditioner {
public:
typedef Preconditioner Base;
BlockJacobiPreconditioner() ;
virtual ~BlockJacobiPreconditioner() ;
/* Computation Interfaces for raw vector */
virtual void solve(const Vector& y, Vector &x) const;
virtual void transposeSolve(const Vector& y, Vector& x) const ;
// virtual void fullSolve(const Vector& y, Vector &x) const ;
virtual void build(
const GaussianFactorGraph &gfg,
const KeyInfo &info,
const std::map<Key,Vector> &lambda
) ;
protected:
void clean() ;
std::vector<size_t> dims_;
double *buffer_;
size_t bufferSize_;
size_t nnz_;
};
/*********************************************************************************************/
/* factory method to create preconditioners */
boost::shared_ptr<Preconditioner> createPreconditioner(const boost::shared_ptr<PreconditionerParameters> parameters);

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@ -50,7 +50,47 @@ using symbol_shorthand::X;
using symbol_shorthand::L;
/* ************************************************************************* */
TEST( NonlinearOptimizer, optimization_method )
TEST( PCGSolver, llt ) {
Matrix R = (Matrix(3,3) <<
1., -1., -1.,
0., 2., -1.,
0., 0., 1.);
Matrix AtA = R.transpose() * R;
Vector Rvector = (Vector(9) << 1., -1., -1.,
0., 2., -1.,
0., 0., 1.);
// Vector Rvector = (Vector(6) << 1., -1., -1.,
// 2., -1.,
// 1.);
Vector b = (Vector(3) << 1., 2., 3.);
Vector x = (Vector(3) << 6.5, 2.5, 3.) ;
/* test cholesky */
Matrix Rhat = AtA.llt().matrixL().transpose();
EXPECT(assert_equal(R, Rhat, 1e-5));
/* test backward substitution */
Vector xhat = Rhat.triangularView<Eigen::Upper>().solve(b);
EXPECT(assert_equal(x, xhat, 1e-5));
/* test in-place back substitution */
xhat = b;
Rhat.triangularView<Eigen::Upper>().solveInPlace(xhat);
EXPECT(assert_equal(x, xhat, 1e-5));
/* test triangular matrix map */
Eigen::Map<Eigen::MatrixXd> Radapter(Rvector.data(), 3, 3);
xhat = Radapter.transpose().triangularView<Eigen::Upper>().solve(b);
EXPECT(assert_equal(x, xhat, 1e-5));
}
/* ************************************************************************* */
TEST( PCGSolver, dummy )
{
LevenbergMarquardtParams paramsPCG;
paramsPCG.linearSolverType = LevenbergMarquardtParams::Iterative;
@ -69,6 +109,26 @@ TEST( NonlinearOptimizer, optimization_method )
DOUBLES_EQUAL(0,fg.error(actualPCG),tol);
}
/* ************************************************************************* */
TEST( PCGSolver, blockjacobi )
{
LevenbergMarquardtParams paramsPCG;
paramsPCG.linearSolverType = LevenbergMarquardtParams::Iterative;
PCGSolverParameters::shared_ptr pcg = boost::make_shared<PCGSolverParameters>();
pcg->preconditioner_ = boost::make_shared<BlockJacobiPreconditionerParameters>();
paramsPCG.iterativeParams = pcg;
NonlinearFactorGraph fg = example::createReallyNonlinearFactorGraph();
Point2 x0(10,10);
Values c0;
c0.insert(X(1), x0);
Values actualPCG = LevenbergMarquardtOptimizer(fg, c0, paramsPCG).optimize();
DOUBLES_EQUAL(0,fg.error(actualPCG),tol);
}
/* ************************************************************************* */
int main() {
TestResult tr;