gtsam/gtsam/linear/GaussianConditionalUnordere...

95 lines
4.0 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 GaussianConditional-inl.h
* @brief Conditional Gaussian Base class
* @author Christian Potthast
*/
// \callgraph
#pragma once
#include <boost/range/join.hpp>
#include <boost/assign/list_of.hpp>
namespace gtsam {
/* ************************************************************************* */
template<typename PARENTS>
GaussianConditionalUnordered::GaussianConditionalUnordered(Index key, const Vector& d,
const Matrix& R, const PARENTS& parents, const SharedDiagonal& sigmas) :
BaseFactor(boost::join(boost::assign::cref_list_of<1>(std::make_pair(key, R)), parents), d, sigmas),
BaseConditional(1) {}
/* ************************************************************************* */
template<typename TERMS>
GaussianConditionalUnordered::GaussianConditionalUnordered(const TERMS& terms,
size_t nrFrontals, const Vector& d, const SharedDiagonal& sigmas) :
BaseFactor(terms, d, sigmas), BaseConditional(nrFrontals) {}
/* ************************************************************************* */
template<typename KEYS>
GaussianConditionalUnordered::GaussianConditionalUnordered(
const KEYS& keys, size_t nrFrontals, const VerticalBlockMatrix& augmentedMatrix, const SharedDiagonal& sigmas) :
BaseFactor(keys, augmentedMatrix, sigmas), BaseConditional(nrFrontals) {}
/* ************************************************************************* */
template<typename ITERATOR>
GaussianConditionalUnordered::shared_ptr GaussianConditionalUnordered::Combine(ITERATOR firstConditional, ITERATOR lastConditional)
{
// TODO: check for being a clique
// Get dimensions from first conditional
std::vector<size_t> dims; dims.reserve((*firstConditional)->size() + 1);
for(const_iterator j = (*firstConditional)->begin(); j != (*firstConditional)->end(); ++j)
dims.push_back((*firstConditional)->dim(j));
dims.push_back(1);
// We assume the conditionals form clique, so the first n variables will be
// frontal variables in the new conditional.
size_t nFrontals = 0;
size_t nRows = 0;
for(ITERATOR c = firstConditional; c != lastConditional; ++c) {
nRows += dims[nFrontals];
++ nFrontals;
}
// Allocate combined conditional, has same keys as firstConditional
Matrix tempCombined;
VerticalBlockView<Matrix> tempBlockView(tempCombined, dims.begin(), dims.end(), 0);
GaussianConditional::shared_ptr combinedConditional =
boost::make_shared<GaussianConditional>(
(*firstConditional)->begin(), (*firstConditional)->end(), nFrontals, tempBlockView, Vector::Zero(nRows));
// Resize to correct number of rows
combinedConditional->matrix_.resize(nRows, combinedConditional->matrix_.cols());
combinedConditional->rsd_.rowEnd() = combinedConditional->matrix_.rows();
// Copy matrix and sigmas
const size_t totalDims = combinedConditional->matrix_.cols();
size_t currentSlot = 0;
for(ITERATOR c = firstConditional; c != lastConditional; ++c) {
const size_t startRow = combinedConditional->rsd_.offset(currentSlot); // Start row is same as start column
combinedConditional->rsd_.range(0, currentSlot).block(startRow, 0, dims[currentSlot], combinedConditional->rsd_.offset(currentSlot)).operator=(
Matrix::Zero(dims[currentSlot], combinedConditional->rsd_.offset(currentSlot)));
combinedConditional->rsd_.range(currentSlot, dims.size()).block(startRow, 0, dims[currentSlot], totalDims - startRow).operator=(
(*c)->matrix_);
combinedConditional->sigmas_.segment(startRow, dims[currentSlot]) = (*c)->sigmas_;
++ currentSlot;
}
return combinedConditional;
}
} // gtsam