gtsam/gtsam/slam/KarcherMeanFactor-inl.h

80 lines
2.3 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 KarcherMeanFactor.cpp
* @author Frank Dellaert
* @date March 2019
*/
#pragma once
#include <gtsam/nonlinear/GaussNewtonOptimizer.h>
#include <gtsam/nonlinear/NonlinearFactorGraph.h>
#include <gtsam/slam/KarcherMeanFactor.h>
#include <optional>
using namespace std;
namespace gtsam {
template <class T, class ALLOC>
T FindKarcherMeanImpl(const vector<T, ALLOC>& rotations) {
// Cost function C(R) = \sum PriorFactor(R_i)::error(R)
// No closed form solution.
NonlinearFactorGraph graph;
static const Key kKey(0);
for (const auto& R : rotations) {
graph.addPrior<T>(kKey, R);
}
Values initial;
initial.insert<T>(kKey, T());
auto result = GaussNewtonOptimizer(graph, initial).optimize();
return result.at<T>(kKey);
}
template <class T>
T FindKarcherMean(const std::vector<T>& rotations) {
return FindKarcherMeanImpl(rotations);
}
template <class T>
T FindKarcherMean(const std::vector<T, Eigen::aligned_allocator<T>>& rotations) {
return FindKarcherMeanImpl(rotations);
}
template <class T>
T FindKarcherMean(std::initializer_list<T>&& rotations) {
return FindKarcherMeanImpl(std::vector<T, Eigen::aligned_allocator<T> >(rotations));
}
template <class T>
template <typename CONTAINER>
KarcherMeanFactor<T>::KarcherMeanFactor(const CONTAINER &keys, int d,
std::optional<double> beta)
: NonlinearFactor(keys), d_(static_cast<size_t>(d)) {
if (d <= 0) {
throw std::invalid_argument(
"KarcherMeanFactor needs dimension for dynamic types.");
}
// Create the constant Jacobian made of d*d identity matrices,
// where d is the dimensionality of the manifold.
Matrix A = Matrix::Identity(d, d);
if (beta) A *= std::sqrt(*beta);
std::map<Key, Matrix> terms;
for (Key j : keys) {
terms[j] = A;
}
whitenedJacobian_ =
std::make_shared<JacobianFactor>(terms, Vector::Zero(d));
}
} // namespace gtsam